text:
Design for the Environment/Residential Wall Insulation

Insulative materials work to reduce the transfer of heat. In residential applications their purpose is to allow a residential home to maintain a different temperature environment than the external surroundings without excessive energy inputs. Three insulation materials were chosen for a comparison to determine the most suitable material to be used in residential wall insulation. The three alternatives were rock wool, cellulose paper and flax paper. With increased public awareness with regards to environmental issues, future home owners would benefit from knowing which of the three materials provides the least environmental impact, best functional performance and is the most economical choice; and these factors were the basis for the comparison.

Mineral wool is manufactured from an abundant natural resource in volcanic diabase rock. This natural resource produces 38,000 times more rock then is being used to manufacture the mineral wool. This material is then put into a furnace and heated to 1500°C. This liquid stone is then spun into fibres and blown by gas to make them finer until the ideal material properties are achieved. Mineral wool has been installed in houses as an insulation material from as early as the 1880’s.

Flax paper is manufactured from the unused portions of the flax plant. Combinations of coarse and fine flax fibres can be blended and processed to produce the insulative material. The flax plant has been used since the Neolithic times but only recently has emerged as an insulating material because of its biodegradable nature and low health risk (as opposed to the once widely used asbestos insulation).

Cellulose paper is an environmentally friendly choice because it is made of 80% recycled newspaper. Both cellulose and fibres are chemically treated with a non-toxic substance to resist fire, insects and mould. Cellulose paper has been used in residential insulation since the 1980’s.

Project Information
Section 2 (Group 18)

Ahmad Osman (osmanah1) Justin Baney (Justin B) Suthakar Sabapathy (sabapath) Kobtham Chotruangprasert (kobthamc)

Highlights and Recommendations
Functionally, each of the three alternatives provide low heat transfer values and high sound absorption coefficients. In addition to this, rock wool is naturally resistant to fire, has low water absorption and is not very hospitable to living organisms. Whereas flax and cellulose require additives for fire safety, are more susceptible to absorbing water (which would in turn increase their heat transfer values) and can develop mould under moist and humid conditions.

In both the streamlined lifecycle assessment (SLCA) and the economic input-output life cycle assessment (EIOLCA) rock wool had the best performance. In the SLCA rock wool received the highest overall score of 63 (out of 100). Rock wool received consistently high totals (except in the area of gaseous emissions in which all alternatives faired poorly). It distinguished itself apart from the other alternatives in the material selection portion of the analysis with a very high score of 17 (out of 20). The major issue with cellulose was that there were many solid residue emissions at several points during the lifecycle including the requirement that material be land filled at the end of life. The issue with flax had to do with the energy expenditures required and residues produced during the manufacturing stage in which it ended up receiving a score of 5 (out of 20).

The chart below summarizes the findings for 1000 houses from the EIOLCA:

These results show that rock wool has the least environmental impact out of all three alternatives followed by cellulose and then flax. Rock wool has lower amounts of toxic releases, green house gas emissions, and energy requirements. Cellulose emits fewer conventional air pollutants than rock wool but has higher emissions in the other categories. Flax generates more economic activity than the other alternatives which is beneficial but this is at the expense of very high emissions in all the other categories. The savings during use phase are substantial for all alternatives, although the differences between each one are not significant.

Residential wall insulations save energy during the use stage of the material and when considering overall costs there are actually savings. The savings are considerably high for an insulation lifetime of 50 years for all three materials.

The chart below outlines direct and indirect costs for 1000 houses:

The savings are highest for rock wool with cellulose having comparable savings. Cellulose had lower indirect costs due to lower conventional emissions but rock wool makes up for these in lower material and manufacturing costs. Flax has higher costs than both but despite that it is still able to provide an overall cost savings.

Throughout this study rock wool insulation has shown itself to be the best choice in terms of functional properties, reduced environmental impact, and economics. It is the recommended choice to be used future residential wall insulation applications.

Functional Analysis
The primary function of wall insulation is to slow the heat transfer across the wall in order to reduce the cost of heating and cooling the house. Although this is the primary function of wall insulation there are other functional considerations. These considerations include the material’s ability to resist fire; its water absorption properties; its acoustic insulation properties; and its resistance to insects, mould and other pests.

Functionally these insulation choices are very similar as they all provide low values of heat transfer and high sound absorption coefficients that are all within range of each other. Rock wool has a thermal conductivity value of 0.038 W/m°K, flax paper has a value of 0.037 W/m°K and cellulose paper has a value of 0.035 W/m°K. Each of the materials have sound absorption coefficients ranging from 0.9 to 0.95.

There are a few differences in functional considerations such as how well each material resists fire. It was discovered that rock wool is naturally resistant while flax and cellulose paper require additives for fire prevention. Other differences were found where rock wool is resistant to living organisms while flax and cellulose paper can develop mould under certain conditions.

Despite the fact that flax was the best economic choice when considering heat loss, it was only marginally better than rock wool. Also, flax and cellulose are more susceptible to water absorption than rock wool ; this in turn would increase their values of thermal conductivity, indicating that in practice rock wool may actually be the best choice in this category as well. Collectively, these properties indicate that rock wool appears to have the best overall properties when it comes to functionality.

Streamlined Life Cycle Assessment
A streamlined life cycle assessment (SLCA) has been preformed for each of the three alternatives. Performing a SLCA encompasses all stages of the product life cycles and allows for consideration of environmental stressors that may have otherwise been missed. The SLCA is also a simple assessment that allows for comparison between alternatives. Rankings for each category range from 0 to 4 with 0 being the worst and 4 being the best.

Pre-manufacturing
The main raw materials in the pre-manufacturing of rock wool is 71% natural stones such as diabase, Gotland stone, lime stone, and bauxite, which are used in the production of briquettes. Industrial waste also contributes to 21% of raw materials, specifically from cement and steel production, and also from disposed stone wool waste. Materials such as phenol, formaldehyde, and urea are produced on site and contribute to 8% of the total material input; these are used as binders in the manufacturing process. The raw materials used are in abundance, and the pre-manufacturing stage incorporates the waste of other industries (specifically the steel industry) as material inputs.

However, toxic materials such as phenol and formaldehyde are also used as binders and are material inputs. The total energy used to generate briquettes and binders are 0.62MJ and 2.66MJ respectively, which is not very high when compared to other alternatives. This product also minimizes the use of virgin materials. The score for solid residues is high because they are reusable, whereas the liquid and gaseous residues produced are not.

Manufacturing
A large portion of the material that is used to create rock wool comes from the byproducts of the steel making industry. Also, the rock wool itself is recyclable and reusable, therefore, the score for material use is high. The manufacturing process for the creation of stone wool is very energy intensive. The energy consumption to create one kg of stone wool is 15.1 MJ, which is considerably high. A large amount of the residues are either recyclable or can be used in other industries. For example, the waste material in briquette production is used in Grodan production and other production sites.

Packaging and Product Delivery
The stone wool is packaged into polyethylene foil, and then transported via trucks, to the desired destination. Care must also be taken in handling the material, because it has been known to cause irritation. The energy used to transport the material is considered a fraction of the energy used to manufacture the material. For transportation, no liquid and solid residues are used, however air emissions are significant. However, solid residues from the packaging exist.

Product Use
No additives are necessary for enhancing the properties of the rock wool material. Using an Australian standard, the AIS Granulated rock wool was given the best possible results, which was a zero rating for ignitability, spread of flame, heat evolved, and smoke developed categories. In general, rock wool is the only material to give a noncombustible rating when tested to international standards such as ASTM E-136-82, and ISO R1182 . Therefore, no fire retardant chemicals are necessary. This material also has no nutrients and therefore, no mould build-up will occur. There are low amounts of solid, liquid, and gaseous residues. However, there are still small amounts of rock wool emissions for all three residues during this stage. A very small portion of solid waste is hazardous, while nitrogenous matter and phosphates are emitted into waste water. Also, small amounts of ammonia, hydrocarbons (except CH4), and VOCs (Volatile Organic Compounds) are released into the air.

Recycling/Disposal
Rock wool is highly recyclable and can be put back into the pre-manufacturing and manufacturing processes . For the energy consumption, trucks must be used to transport the material and energy must be used to filter the material . Since this material is recyclable, it receives a high score for solid waste, and liquid waste. However, a lower score is given to gaseous residues because of the emissions into the air caused through truck transportation.

Pre-manufacturing
The primary materials used in the production of the insulation are the flax fibres, polyester and diammonium hydrogen phosphate, accounting for 75%, 15% and 9%, respectively. Flax requires mostly virgin material for the initial production of insulation, but it is also a widely available renewable resource and quite recyclable. The use of farming equipment used in extracting flax from the fields is not an energy intensive process. A single tractor may be used to extract several tons of flax in a midsized field, which can produce a large quantity of insulation. Relative to other farmed crops, flax yielded the lowest output/input energy ratio (1.62 MJout/MJin) . The energy input into harvesting this material does not come near to that of extracting more dense raw materials such as metals and minerals.

Using of farming equipment such as tractors and tillers which run on diesel, large amounts of air pollutants such as CO, SO2 and NOx are produced and emitted into the atmosphere . On the other hand solid and liquid residues are quite negligible and if any occur they would mainly be due to oil leaks from equipment and replacement of wearing parts. Virtually all parts of the plant are used from the yield of flax fibres and straw to the shives and seeds of the plant. The roots are the only source of solid material left behind after harvesting. Flax seeds and tow are bi-products when harvesting for flax fibres, but these bi-products are used in different industries for things such as medicine and papers.

Manufacturing
Besides the main composition of ingredients which make up the majority of the insulations weight, there are also a variety of other small substances such as borax and even uranium, which contribute to the product of small amounts of hazardous waste. It is surprising to find out that manufacturing flax insulation requires a high level of fossil fuels, electricity and non-renewable fuels seeing how it’s a renewable resource itself. It requires 84 MJ/kg to hold the flax fibres to a polyester binder. Relative to stone wool, it consumes approximately 20 times more renewable energy. For these reasons flax deserves a ranking of 0 for its high energy requirements. When it comes to output residues in the manufacturing process, flax is not so great. It generates a very large amount of waste water during the retting process which is equivalent to 5 times the weight of flax being produced. A large portion of the solid waste produced is due to the machining process of sheets of insulation slabs. Flax also produces a large volume of CO2 due to energy production required for manufacturing from fossil fuels.

Packaging and Product Delivery
Packaging of flax accounts for about 1 kg for every 1000 kg of flax produced . The packaging is made out of high density polyethylene. Polyethylene requires the use of toxic chemicals in its production. Its manufacture requires 1.75 kg of petroleum in order to create 1 kg of high density polyethylene but it can be recycled and reused although the quality slightly decreases with remelting of the plastic . The method of transportation is by truck (flax is grown in Canada) which uses minimal energy compared to other alternatives such as by airplane or boat if distribution is required overseas. Once again the solid residues and liquid resides are similar to that of the pre-manufacturing stage where diesel powered tractors and various farming equipment is used for preparation of the flax.

Product Use
During the installation of flax insulation, workers who are constantly inhaling flax particles on a regular basis have been known to develop byssinosis or brown lung disease. Because the use of flax insulation is a relatively new product, this may be a problem to home owners in the future if exposed holes or leaks in the wall allow the insulation to release any forms of particulate matter. The insulation’s function is to reduce the amount of heat transfer through the walls this is a passive process and no energy expenditure is required. There are no gaseous residues which are emitted during the use of the insulation. However, solid particles of may be emitted this may be a health concern if loose flax particles are constantly being breathed in.

Recycling/Disposal
Although flax insulation can be recycled, the best method for disposal of the insulation is using incineration with energy recovery which can prevent 8% of the overall consumption of fossil fuels from being used . It might have been expected that land filling a renewable resource which comes from a plant (flax) would be the best method of disposal because it is biodegradable, but in fact it is in the worst method . The reason is due to the production of methane from the anaerobic degradation of the flax which heavily contributes to greenhouse gas emissions . The most energy consumption takes place in the disposal phase for flax insulation. Regardless of the different scenarios for disposal indicated in the sensitivity analysis, at least 80% of the insulation will be recycled which requires a total of about 50 MJ for every kilogram of insulation being disposed of. Few liquid residues are produced during disposal.

Pre-manufacturing
The main raw materials in the pre-manufacturing of cellulose paper insulation are 75% to 80% ONP (old newspaper), and retardant chemicals (borates and/or ammonium sulphates) . As a result of ONP availability, the score for material choice is high; although full marks are not earned since the chemicals used as fire retardant are “irritants”, and sulphate (SO4) in the ammonium sulphate compound can be the source of emission of sulphur dioxide (SO2) which can cause acid rain thereby impacting the environment . According to Hendrickson, used paper can emit methane (CH4) which is regarded as one of the greenhouse gases contributing in the emission of carbon dioxide (CO2) . However, the emission of such gases is low and almost negligible . In the paper-recycling process, energy is not extensively used because most of the waste removal, such as removal of ink and “stickies” (various adhesives used in printing), and removal of large objects such as plastic bags or cans, is done by flotation in mechanical cells. Water can be recycled, but solid wastes such as rejected ink must be land filled and are not recyclable. Chemicals used in de-inking and sticky-removal process are sodium hydroxide, fatty acid soap, hydrogen peroxide, a chelating agent, and sodium silicate .

Manufacturing
Recycled paper and fire retardant chemicals are manufactured in a closed-loop fashion and are reusable, and energy use in the manufacturing life stage is low, as cellulose having the lowest embodied energy of 1.75 MJ/kg, while mineral wool has the second lowest value of 15.1 MJ/kg . The process of manufacturing cellulose fibre insulation mostly involves emissions of solid residues such as residual particles. These particles are air-conveyed to the storage bin, and are not recyclable, but only small amount of these particles are emitted and no significant liquid or gaseous residues are emitted at this life stage .

Packaging and Product Delivery
A residential household described their experience with the installation of their cellulose insulation and they pointed out that the material used to pack the cellulose insulation was “non-biodegradable plastic” . The transportation means for cellulose insulation is by truck. The energy used to transport and install the material is similar to the manufacturing stage . There are some solid residues during the installation since cellulose is mostly loose-filled to the wall cavity, and the risk of exposure to dust and fire- or mould-resistant chemicals from loose-filled materials is high . No liquid and solid residues are emitted during transportation, but gaseous residues are considerably large from truck transportation.

Product Use
Although no further chemicals are added in the product use stage, the fire- and mouldretardant chemicals that were added in the product manufacturing stage can result in certain issues during the product use stage. For example, borates are water soluble and they leach out if the insulation gets wet, while another alternative, ammonium sulphate, makes metals corrode when they come into contact. Loose-fill insulation can also settle and reduce R-value as the result of the wind that brings dust and dirt to accumulate either by “compressing the insulation or by filling air pockets”. Fire and mould retardant chemicals may be hazardous if the cellulose insulation is not properly installed . If the insulation is exposed to excessive moisture then there could be mould build up at certain temperatures or the washing away of the fire retardant.

Recycling/Disposal
Cellulose insulation is land filled at the end-of-life stage. Even though cellulose insulation is produced from recycled newspaper, cellulose insulation is not recyclable. This is mainly due to the degradation of the paper quality after the paper recycling process . As discussed in the pre-manufacturing life stage, land fill of paper or paper products results in the emission of the greenhouse gas, methane (CH4). Truck transportation is used to transport cellulose waste to the land fill, hence low score on solid and gaseous residues.

Economical Input-Output Life Cycle Assessment (EIOLCA)
An EIOLCA was performed on each of the three insulation alternatives. The EIOLCA software identifies all of the different economic transactions, environmental emissions and resource requirements needed for the production of a product or service in quantitative terms. This Life Cycle Assessment focuses only on the pre-manufacturing, manufacturing, and product use stages. The transportation and disposal stages of the product are not considered in this analysis. The method of transportation is very similar for all alternatives and along with the disposal stage they are both out of the scope of the EIOLCA.

Rock Wool Insulation
The following table gives the general material composition for rock wool insulation.

The raw materials of rock wool undergo many processes to form the final product. Once the raw materials are acquired through mining and recycled industrial waste (briquette production), they are melted and then cooled rapidly to form non-crystalline fibres. These fibres then go through a wheel centrifuge process to form spindle fibres, which enhances the properties of the material. For this LCA, it is assumed that binders are used to further enhance the mechanical properties of the product for insulation. It should be noted that the outputs at any of these manufacturing stages can be used as inputs into other sectors of the industry. For the environmental analysis, a producer’s price of $848,000 was calculated for 1000 houses and was inputted into the mineral wool manufacturing sector.

Flax Insulation
The following table gives the general material composition for flax insulation.

Pesticides are required to maintain the good health of the flax plants against many insects and parasites such as grasshoppers and worms. Chemicals contribute to a large amount of material inputs, which are used within the manufacturing process to enhance the fire retardant properties of the flax plants. The producer’s price of flax insulation was $1,225,630, which was calculated for 1000 houses and was inputted into a hybrid sector with oil seed farming as the base.

Cellulose Insulation
The following table gives the general material composition for cellulose insulation manufactured by GreenFiber who claim to only use ONP (old newspaper) as raw materials.

In this life cycle analysis, the raw materials are ONP (old newspaper), and retardant chemicals. After acquiring ONP, it goes into the recycling process in the pulp mills, which de-ink and remove sticky materials by flotation in mechanical cells; chemicals (i.e. sodium hydroxide, fatty acid soap, and hydrogen peroxide) are introduced in the pulper that make the ink and stickies become attached to the air bubbles and rise up to the top of the cell, and later removed as rejects. After the paper recycling process, recycled newspaper goes to the cellulose production process. According to the manufacturing process of cellulose insulation, recycled newspaper is size-reduced until cellulose fibers of 20 to 30 microns in size are obtained. Fire and mold retardant chemicals are then applied to the cellulose fibers, and the fibers are then dried and made ready for packaging and shipment. Similarly to flax insulation, the producer’s price of $1,503,580 was calculated for 1000 houses and was then inputted into a hybrid sector with oil seed farming as the base.

Comparison of Pre-manufacturing and Manufacturing Phases
For rock wool, the EIOLCA shows that the pre-manufacture and manufacturing stage involves a total of $1.69 million in economic activity, the production of 37.11 metric tons of conventional air pollutants, 1120 metric tons of CO2 equivalent greenhouse gas emissions, 1670 kg of toxic releases, and uses 15.5 terajoules of energy. For flax, the EIOLCA shows that the pre-manufacture and manufacturing stage involves a total of $3.45 million in economic activity, the production of 59.08 metric tons of conventional air pollutants, 2664 metric tons of CO2 equivalent greenhouse gas emissions, 3395 kg of toxic releases, and uses 35.8 terajoules of energy. Lastly, for cellulose the EIOLCA shows that the pre-manufacture and manufacturing stage involves a total of $3.34 million in economic activity, the production of 25.95 metric tons of conventional air pollutants, 1420 metric tons of CO2 equivalent greenhouse gas emissions, 1980 kg of toxic releases and uses 19.3 terajoules of energy. These results show that rock wool has the least environmental impact out of all three alternatives since its values for greenhouse gas emissions, toxic releases and energy usage are the lowest of the three. When it comes to conventional air pollutants cellulose performs a bit better. Flax on the other hand finishes last in all categories and appears to be the worst choice in terms of environmental impact.

Use
The lifetime use of each insulation material in a residential wall application is assumed to last for 50 years. To determine how much energy is saved in this phase, an in-depth approach was applied for each of the insulation materials.

For rock wool, equations that incorporated the conductivity and surface area of the insulation were used to determine the heat and energy lost through the material. Comparing this value to the average energy intensity required to maintain a certain temperature within a single detached home, the energy saved was calculated. Finally, this value was assumed to be contributing only to the savings of natural gas within a hot air furnace. This assumption was used to find the monetary value of natural gas saved over a life cycle of 50 years, which was $90,942,500 for 1000 houses. The same methods were applied for flax paper insulation and cellulose paper insulation.

For flax a value of $91,503,000 was obtained and for cellulose a value of $92,183,500 was obtained. Inputting these values into the natural gas distribution sector, a large amount of savings of conventional air pollutants, greenhouse gases, energy, and toxic releases were observed.

The largest contributors to conventional air pollutants were the VOC emissions. This came from the natural gas distribution sector. The amount of greenhouse gases saved was 202,500 MTCO2E over the use life cycle of the insulation. The major contributor was again the natural gas and distribution sector. The largest amount of energy savings came from pipeline transportation of natural gas, which was reflected in our original assumption of all the energy savings going into the amount of natural gas used to heat the house. The total amount of energy saved was 1260 TJ. The largest toxic releases were for land releases that came from the copper, nickel, lead, and zinc mining sector. It can be seen that all the savings are 10 to 100 times greater in magnitude than the amounts produced through the pre-manufacturing and manufacturing stages.

Cost Analysis
The direct costs for the insulation of 1000 houses was calculated using the material cost, the cost of power consumption during the pre-manufacturing and manufacturing stages, and the cost of power consumption during the use stage. The manufacturing facilities, and labour costs were considered similar for all the products, and therefore were not taken into account for this analysis. Maintenance and operation costs are considered negligible because the insulation is assumed to last the lifetime of the house being insulated, without being disturbed. The average Ontario electricity spot market price in 2007 was $0.051/kWh. This value was used to convert the power consumptions of the various stages into a monetary value. To calculate the indirect costs for 1000 houses only the air emissions were considered. In 2005, the economic cost for healthcare due to air pollution was $7,809,201,700. The total amount of pollutants that Ontario emitted in that same year was 77.3 MT. These values were then used to calculate the air pollution cost factor (APCF), which was required to calculate the indirect costs. Therefore, the APCF = $$\begin{matrix} \left(\frac{$7,809,201,700}{77,300,000tonnes}\right)=$101.03/tonne \end{matrix}$$. The indirect costs can be calculated using this factor multiplied by the amount of the individual emissions.

Rock Wool
Material Cost = ($848.00/house)(1000 houses) = $848,000 Cost from Manufacturing Stage = $$(15.5 \times 10^9 kJ)\begin{matrix} \left(\frac{1hr}{3600s}\right)\left(\frac{$0.051}{kWh}\right)\end{matrix}$$=$219,583 Cost from Use Stage = $$(1260 \times 10^9 kJ)\begin{matrix} \left(\frac{1hr}{3600s}\right)\left(\frac{$0.051}{kWh}\right)\end{matrix}$$=$17,850,000 For a Use stage of 50 years: = $848,000 + $219,583 - $17,850,000 = -$16,782,417

Flax Insulation
Material Cost = ($1,352.39/house)(1000 houses) = $1,352,390 Cost from Manufacturing Stage = $$(35.866 \times 10^9 kJ)\begin{matrix} \left(\frac{1hr}{3600s}\right)\left(\frac{$0.051}{kWh}\right)\end{matrix}$$=$508,102 Cost from Use Stage = $$(848 \times 10^9 kJ)\begin{matrix} \left(\frac{1hr}{3600s}\right)\left(\frac{$0.051}{kWh}\right)\end{matrix}$$=$12,013,333 For a Use stage of 50 years: = $1,352,390 + $508,102 - $12,013,333 = -$10,152,842

Cellulose Paper
Material Cost = ($1,503.58/house)(1000 houses) = $1,503,580 Cost from Manufacturing Stage = $$(19.28 \times 10^9 kJ)\begin{matrix} \left(\frac{1hr}{3600s}\right)\left(\frac{$0.051}{kWh}\right)\end{matrix}$$=$273,133 Cost from Use Stage = $$(1280 \times 10^9 kJ)\begin{matrix} \left(\frac{1hr}{3600s}\right)\left(\frac{$0.051}{kWh}\right)\end{matrix}$$=$18,133,333 For a Use stage of 50 years: = $1,503,580 + $273,133 - $18,133,333 = -$16,356,620

Indirect Costs
Indirect costs are calculated using the sum of indirect costs from emissions of conventional air pollutants and GHG, where APCF = $101.03/tonne, and factor for $$\mbox{CO}_2$$ emitted is $16/tonne.

Rock Wool
Indirect costs of conventional air pollutant emissions = $3,749.21 Indirect costs of GWP = $17,920 Hence, total indirect costs of Rock Wool insulation = $3,749.21 + $17,920 = $21,669.21

Flax Insulation
Indirect costs of conventional air pollutant emissions = $5,968.86 Indirect costs of GWP = $42,624 Hence, total indirect costs of Rock Wool insulation = $5,968.86 + $42,624 = $48,592.86

Cellulose Paper
Indirect costs of conventional air pollutant emissions = $2,624.85 Indirect costs of GWP = $22,752 Hence, total indirect costs of Rock Wool insulation = $2,624.85 + $22,752 = $25,376.85

Rock Wool
The largest potential health effects occur during the installation phase of the product. The spread of dust must be prevented; otherwise it will enter the body through inhalation. During a short period of exposure, the substance will irritate the eyes, the skin, and the respiratory tract. Over a longer period, the substance will cause sore throat, laboured breathing, redness and itching of the skin and eyes. The insulation was originally thought of as carcinogenic, however in 2001, it was re-evaluated and is now considered as non-carcinogenic to humans. The following preventative measures should be taken when installing the insulation. A mask should be worn to prevent inhalation of dust particles, protective gloves and clothing are needed to protect skin, and finally safety goggles should be worn to prevent exposure of eyes to dust particles.

Flax Insulation
For flax, health problems such as byssinosis can be attained in the similar manner through the inhalation of flax particles during the installation of the material. Similar precautions must be taken by textile workers who install this material on a regular basis. In today’s society as environmental impacts on the Earth are becoming more of a concern people are looking towards more environmentally friendly solutions for today’s problems. Flax is a relatively new insulation product and the demand is still growing each year due to the awareness that it is an easily decomposable material when its useful life is over. Little do the public know that throughout the entire life cycle of flax, it is one of the least environmentally friendly alternatives. The problem is that the public generally don’t look at any other phase except the most obvious ones such as “recyclability after I’m done with it” and “what this product is made from”.

Cellulose Paper
Today's cellulose insulation concerns are primarily from the fluctuation of ONP prices, and problems caused by chemical additives ,. The cellulose insulation business became less substantial as cellulose insulation manufacturers dropped from 700 to about 65 during the 1970s and 1980s, and the ONP prices climbed up to 500% as the business rose again in 1994. As cellulose insulation currently on the market competes with fibreglass insulation, cellulose insulation seems to be winning the market share according to Built Green Colorado due to the wake of green awareness in the society. Many studies have been done and shown that the both chemical additives used as fire or mold retardants (i.e. boric acid and/or ammonium sulphate) may irritate eyes and skin, and corrode metals in contact with the insulation.


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Learning the basics of French/Introducing Yourself

This lesson contains the basic French alphabet and pronunciation guide, along with common phrases used for introductions.

French alphabet
This is the French alphabet with approximate pronunciation and IPA (see also: IPA for French and French phonology).

 * {| class="wikitable"

! rowspan=2 | Letter || colspan=2 | Pronunciation ! IPA || Approximate
 * A || || ah
 * B || || bay
 * C || || say
 * D || || day
 * E || || euh (like Am. English "look")
 * F || || eff
 * G || || jay
 * H || || ash
 * I || || ee (like English "e")
 * J || || gee (Warning: Don't confuse with "g")
 * K || || kah
 * L || || ell
 * M || || emm
 * N || || enn
 * O || || oh
 * P || || pay
 * Q || || kooh
 * R || || air
 * S || || ess
 * T || || tay
 * U || || ooh
 * V || || vay
 * W || || doobluh vay
 * X || || eeks
 * Y || || ee grek
 * Z || || zed
 * }
 * N || || enn
 * O || || oh
 * P || || pay
 * Q || || kooh
 * R || || air
 * S || || ess
 * T || || tay
 * U || || ooh
 * V || || vay
 * W || || doobluh vay
 * X || || eeks
 * Y || || ee grek
 * Z || || zed
 * }
 * U || || ooh
 * V || || vay
 * W || || doobluh vay
 * X || || eeks
 * Y || || ee grek
 * Z || || zed
 * }
 * Y || || ee grek
 * Z || || zed
 * }
 * Z || || zed
 * }

It is important to realize that several sounds greatly differ in French:
 * the letter a is only pronounced "ah"
 * the letter e (by itself) is only pronounced "euh" (when it takes the accent ´like é it is pronounced "ay")
 * the letter i is only pronounced "ee"
 * the letter h is normally silent, and rarely pronounced

There are five accents within French:

In Romance Languages, it is common to have a formal and informal way to say "you." In French, we have tu (informal) and vous (formal), and each is conjugated differently, as you will see later on. To help determine which form of "you" should be used, one must consider the other person's age, profession, and overall relationship.

If the other person is a minor, very close personally, or a family member, "tu" should be used. If the other person is an adult, not very well known, or a stranger, "vous" should be used.

You will see demonstrations in the dialogues below.

Être and avoir
Être and avoir are the first two important verbs you will need. Before you can use them, you need to understand the available targets within French:

Être means to be, and avoir means to have.

Exercises
Exercises


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User talk:THuen

Hello, welcome around here. I hope you succeed in your learning goals. Below more info about Wikiversity, Erkan Yilmaz uses the Wikiversity:Chat (try) 17:02, 4 April 2008 (UTC)

Welcome
Hello THuen, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
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And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! Erkan Yilmaz uses the Wikiversity:Chat (try) 17:02, 4 April 2008 (UTC)

title: User talk:THuen


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User:Howard12f/DFE2008 Hydrogen Generation 9B

Project Information

Group 9B

Yu-Hao Tseng (howard12f)

Tze Lo

Arthur Cheuk

Denushka Sarathchandra (Sarathc2)


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Design for the Environment/Automobile Engines II

This page is part of the Design for the Environment course

The road transportation sector is a major player in greenhouse gas emissions (GHG) with 137.8 MT of CO2 E in 2005. Out of that, around 57% of GHG emissions originate from the passenger transportation sector alone . The increase in environmental concerns as well as crisis of non-renewable resources coming to an end, entails the automotive industry to look into alternative fuel and engine designs that would run on renewable fuels, have low impact on environment and yet perform as efficiently as gasoline internal combustion engines, which are used in almost all mid-size passenger vehicle. Two different engine designs; Flex Fuel internal combustion engine and Fuel Cell, are studied from economical and environmental aspects over their entire life cycle, to be compared to gasoline internal combustion engine. Then the best alternative is to be chosen and suggested to Toyota.

Internal combustion engines utilize a four stroke design in which they intake a fuel, compress it, ignite it and the release the exhaust. In a gasoline internal combustion engine, gasoline is the fluid used to generate mechanical energy to power the vehicle, whereas in a flex fuel engine, a mixture of gasoline-ethanol is injected into engine and burned. Due to higher existence of oxygen atoms in ethanol, the combustion process of flex fuel engines is more complete, i.e. less CO is emitted and hence less pollution is generated with compared to gasoline. However the low fuel efficiency of these engines requires more frequent refueling, and hence higher energy consumption. As a result a newer concept of engine is introduced, which utilizes the electrical power generated from reaction of hydrogen and oxygen to power the vehicle; namely fuel cell. Even though there are no emissions involved in this new technique, there are high infrastructure costs as well as low to efficiency involved which implies higher degree of development is yet to be done before changing the automobile engine design. A comprehensive cost analysis, economic input-output life cycle analysis and streamlined life cycle assessment is performed to ascertain Toyota that gasoline internal combustion engine is thus by far the best engine design.

Project Information
 Section 1 Group B4  Elmira Kalali (elmira_kalali) Barzin Doroodgar (Barzin) Bogdan Beca (Bbeca) Sumin Baek (SBaek)

Highlights and Recommendation
The relative functional, environmental and economical merits of each fuel alternative are evaluated thoroughly with help of a comprehensive cost analysis, an economical input-output life cycle analysis and streamlined life cycle assessment. It is crucial to recognize that there are trade offs between environmental and economical aspects of a design.

According to the cost division chart shown below, it can be clearly observed that the capital cost of hydrogen fuel is roughly three times larger than that of counterparts; gasoline and flex fuel internal combustion engines. On the other hand, this new technology of using hydrogen and oxygen to generate electricity for powering a mid sized passenger vehicle has a much lower fuel production cost. Clearly, if these three engine design alternatives are compared against each other only based on costs over their entire life stage, gasoline internal combustion engine would have the lowest total cost $53632.02, flex fuel engine would have the second highest total cost, $66,874.58, and fuel cell would have the highest of all, $228,261.2, due to its high indirect and capital cost.

Cost

A closer look at associated costs for each life cycle stage reveals that fuel cell has twice as high manufacturing cost as other two engine designs. On the other hand in fuel production stage, hydrogen fuel cell has significantly lower cost in producing hydrogen than other alternatives, which have to produce gasoline from crude oil and ethanol form corn respectively. Further analysis shows that all three alternatives have similar associated costs during their use stage as well as their end of life stage. Moreover since there are relatively less moving parts in a fuel cell engine, the maintenance cost for such an engine is comparatively lower than gasoline internal combustion engine and flex fuel engine.

Now if all the aforementioned cost values are entered into the economic input-output life cycle analysis model as an input, one would be able to evaluate these alternatives based on their environmental impacts, such as level of air pollutant emission, global warming potential and level of greenhouse gas emissions from each sector of industry involved in the life stage of automobile engine.

From the potential global warming graph shown, it is evident that in general hydrogen fuel cell’s contribution to global warming, measured in metric tones equivalent of CO2, is less than gasoline and flex fuel internal combustion engine. The nil contribution of these engines during their use stage, which reflects their zero tail pipe emission characteristics, makes them a desirable substitute for current gasoline internal combustion engines, which are one of the major contributors to global warming. However, once the fuel production stage of this design is evaluated, high levels of CFCs and CO2 are emitted. But comparing it to that of gasoline internal combustion engine and flex fuel engine, it can be seen that more CO2 is emitted during gasoline and ethanol production processes. An interesting trend is that flex fuel engine produces almost one sixth of CO2 produced when 100% gasoline is used a fuel in an engine to power a vehicle, i.e. gasoline internal combustion engine. That is because ethanol contains more oxygen atoms, which helps the combustion process and thus burns cleaner than counterpart gasoline. Thus the alternatives from least contributor to global warming to most are: hydrogen fuel cell, flex fuel engine and gasoline internal combustion engine.

In addition to global warming, the energy use can be utilized for evaluating the former designs. According to energy graph shown, all three designs, consume the most energy in their fuel production stage and use stage. A more detail examination reveals that flex fuel is the most energy intensive design of all three. This is primarily due to lower energy density of E85. Also the distillation process required in ethanol production involve large electricity input, thus making it the least environmental friendly engine design among the three at hand.

Last but not least, a scoring matrix is employed (shown below) to assess each life cycle of engine design based on material choice input, energy use, solid residues, liquid residues and gaseous residues. The important assumption that is made prior to streamlined life cycle assessment is that the fuel production stage is merged with use stage of the engine. However for a more realistic analysis the fuel production stage is ignored for solid, liquid and gaseous residues produced in use stage. According to total scores for each stage (sum column) one can see that the pre-manufacturing stage of fuel cell has the highest environmental impact. This is mainly due to platinum extraction required for manufacturing of fuel cell components. Even its manufacturing and end of life stages have relatively higher impact on environment when compared to gasoline internal combustion engine and flex fuel engine. The reason for high impact in manufacturing stage is because large infrastructures are required for manufacturing of fuel cell. Moreover the non-renewable characteristics of the polymers used in fuel cells entail incineration and landfill which would damage the environment. On the other hand the zero tail emission of these engines makes them an appealing alternative. This phenomenon is evident by a huge score for use stage. If one is to disregard the severe impact of gasoline internal combustion engine on environment, and look at its all other life stages, it is apparent that is a better choice than flex fuel. Even though ethanol burns cleaner that gasoline, it has lower energy efficiency with compared to gasoline. Based on efficiency of the fuel, gasoline is the best alternative for powering a mid-sized passenger vehicle.

SLCA

Having examined the three alternatives at hand from economical and environmental aspects, it is acceptable to say gasoline internal combustion engine is still the best engine design for mid-sized passenger vehicles, in spite of its high level of air pollutant emission and greenhouse gas emission. One might argue that hydrogen fuel cell appears to be a good alternative with no emission during its operation. However it is clear that the technique is not implementable until an effective cost and energy way of producing it, is developed. Similar analogy exists for flex fuel engines; despite of a cleaner combustion process, the low efficiency of ethanol requires frequent refueling and hence greater energy consumption. In conclusion, based on the quantitative and qualitative data presented, it is suggested that Toyota should power its vehicles with an gasoline internal combustion engine.

Gasoline Internal Combustion Engine
A gasoline internal combustion engine (ICE) operates by converting the chemical energy from the exothermic reaction of a gasoline-air mixture to mechanical energy. In these engines, combustion of gasoline and an oxidizer occurs in a confined space called the combustion chamber. The first step in the combustion process is the intake stage, where the intake valve is opened and fuel mixture is allowed to flow in the combustion chamber. The piston is then moved upwards, compressing the fuel mixture in the compression stage. This is followed by the combustion stage, which is initiated by a high voltage electric spark. The fuel combustion expands the gas inside the chamber which drives the piston down with high power. Finally, in the exhaust stage, the exhaust valve is opened and the piston moves upward pushing the emissions created by the combustion out. The translational movement of a series of pistons are converted to rotational movement of the wheels by means of the crankshaft.

The performance of internal combustion engines varies depending on the size and manufacturer. A typical gasoline ICE of a midsized vehicle has a compression ratio of 10.0. These engines can be run with unleaded fuel with an octane rating of 87 and a fuel economy of 30 to 40 MPG. .

Flex-Fuel Internal Combustion Engine
The flex fuel internal combustion engine (FFICE) used in flexible fuel vehicles (FFVs) works on the same principle as the regular gasoline internal combustion engine. The major difference is that the FFICE uses a mixture of 85% ethanol and 15% gasoline (E85) as the main fuel source. The FFICE usually has lower fuel efficiency compared to the gasoline ICE due the energy density of the fuel being lower than that for gasoline. E85 contains more oxygen atoms than regular gasoline and this produces a cleaner burn with fewer hydrocarbons left in the actual combustion chamber. E85 has a theoretical octane rating of 113 in its purest form which produces a compression ratio of 15 . As noticed, a higher octane rating produces a higher compression ratio which is very important for increasing the thermodynamic efficiency of the engine. However, because the engine has to be compatible with 100% gasoline, lower compression ratios that prevent auto-combustion of gasoline have to be used, thus lowering the thermodynamic efficiency. Additionally, the flex fuel engine contains an Engine Control Unit (ECU) that regulates the flow rate and adjusts the timing of the spark plugs to ensure proper combustion.

Hydrogen Fuel Cell
The direct hydrogen fuel cell automobile propulsion system is composed of a Proton Exchange Membrane Fuel cell (PEMFC) system and a compressed hydrogen tank. Hydrogen fuel is provided to the anode of the fuel cell while oxygen is provided to the cathode through the channel formed on the bipolar plates. At the anode, the platinum catalyst facilitates the breakdown of hydrogen molecules into positively charged hydrogen protons and negatively charged electrons, and these electrons are forced to flow through an external circuit. Meanwhile, at the cathode, the negatively charged electrons, positively charged protons and oxygen combine to produce by-product such as water . For example, the Ballard® Mark902™ fuel cell, used for the automobile propulsion system, produces a continuous stack power of 85kW, 300 Amps of current, and 284volts of DC voltage . In general fuel cells used in automobiles produce 50-85kW, which is a sufficient requirement to power a conventional mid sized vehicle. In general, hydrogen fuel used for the system has the octane rating of 130+ and exhibits energy characteristics of 113,600-134,500 Btu/kg .

Gasoline Internal Combustion Engine
The life cycle cost analysis of the ICE is performed based on the 2009 Toyota Corolla CE. The capital cost of the engine is estimated as $2,718, which is based on the assumption that the manufacturing cost of the engine is about 30% of the automobile production cost. Furthermore, for comparison with the other engine alternatives, the fuel production is included as part of the ICE life time cost analysis, $2.85 per gallon. This takes into account the crude oil production and refinements costs which are reported in 2004 as 50% and 18.5% of the gasoline retail price, respectively. Furthermore, the operating cost of this engine is found to be $31,174 over its life time. which contributes the most to the overall cost of the entire life cycle. Another cost taken into consideration is the maintenance and repair cost of the engine. The maintenance cost is estimated based on the typical costs that are needed to maintain the engine over the entire life time; such as engine tune up, timing belt replacement, engine oil change, radiator flush, etc. The repair costs in this study are based on the revenue data reported by repair services of Canada in 2005. Taking these factors into account over the life cycle of the engine the total maintenance and repair costs are estimated to be $15,117. In addition, in order to integrate the end of life of the engine into the cost analysis, earnings obtained by recycling the engine is included in the cost analysis. This is found to be about $59 and does not have an overall effect on the total cost. Last but not least, the insurance cost of the engine is taken as an indirect cost in this study, which is estimated as 30% of the total insurance cost; i.e. $4,563.

Flex-Fuel Internal Combustion Engine
The most important direct costs shown in the cost division table, are composed of capital costs, fuel production cost, operating cost, repair & maintenance cost and recycling cost. The capital cost is mainly the cost of purchasing the engine minus the inflation and the profit margin. Following the assumption that, typically the cost of an engine is 30% of the cost of a car, using the cost of a 2009 Toyota Corolla CE basic model and including the cost of a Fuel Flex Gold Conversion Kit, which ensures that all the settings of any combustion engine are properly adjusted in order to work with the E85 fuel mixture, the capital cost is $3098.3. The fuel production cost including the cost of feedstock and variable costs such as maintenance, labour and electricity of facilities used for processing  is $0.73/gallon. The operating cost of the FFICE includes the cost of the fuel throughout the lifecycle of the FFV and therefore it is found to be $39,927.05. The repair and maintenance cost, $19,226.8, is mainly concerned with recurring costs such as for tuneups (e.g. engine oil and drive belts replacement)   and with the average cost for repairing or refurbishing an engine. Finally, at the end of the life cycle, the engine is recycled and it is assumed that 95% of it is made of mixed steel and cast iron scrap and 5% of it is made of aluminum. After the engine has been recycled the amount received back from selling the metallic parts back to the recycling companies is $59.43. The indirect cost is mainly composed of the cost of the insurance for the sedan, i.e. 30%, under analysis as given by the Transportation Energy Data Book. Thus at the end of the life cycle the total insurance cost sums to $4563.

Hydrogen Fuel Cell
Despite its environmental merits, fuel cells are slow to commercialize due to their high production cost. Furthermore, the implementation of fuel cell as an automobile propulsion system means establishing a new infrastructure system for the production and delivery of hydrogen fuel. The capital cost associated with a fuel cell automobile propulsion system is $8824 and this cost is considerably higher than the operating, maintenance, or disposal cost which are $3843, $7500, and $441.2, respectively.(see the cost division table above) In addition to the direct cost, the indirect cost related to warranty, health, environment, and society is $207,653. The most significant source of indirect cost is from road infrastructure establishment,health and environmental impacts. The fuel cell automobile propulsion system is not yet widely commericalized and the capital cost of a fuel cell is being actively investigated by many research groups. Moreover, the production cost of the fuel cell is expected to decrease once they are widely implemented by the automobile industry. The capital cost of a fuel cell encompasses a fuel cell stack cost, auxiliary system cost, and a fuel tank cost. The operating cost of the fuel cell is based on the cost of the hydrogen fuel, $0.7/gallons of gasoline equivalent, that the system consumes over its entire life cycle. The cost incurred from maintaining the fuel cell automobile propulsion system is comparatively small since there are very few moving parts. A minimum level of maintenance is required for fuel cell systems. The only maintenance that is required is the occasional changing of air filters and pump check ups. At the end of the life cycle of a fuel cell system, a large portion of the membrane assembly and other fuel components are either incinerated or landfilled at the end of its use. From this it is assumed that the end of life disposal cost of a fuel cell is estimated as 5% of the capital cost.

Economic Input-Output Life Cycle Analysis
To evaluate the environmental impact of automobile engine design, the economic input-output life cycle analysis is employed, based on 1997 Us dollar amount of production.

Gasoline Internal Combustion Engine

Looking at the GWP of each life stage, shown on the figure above, it can be observed that the use phase is the largest contributor to GHG emissions. This is expected since the gasoline engine has a relatively long use phase in which high amounts of CO2 are emitted. Also, it can be concluded from the graph that the gasoline production is a significant factor to the lifetime GWP of the gasoline engine. The major contributing sub- sectors in fuel production are petroleum refineries and oil and gas extraction emitting large amounts of CO2 and CH4, respectively.

The figure above shows the energy use of various life stages of the gasoline engine. The most energy intensive stages are use and fuel production, which is the same trend as seen for the GWP. This is once again due to the relatively long use phase of the engine and the energy intensive processes that take place in petroleum refinement in order to convert heavy hydrocarbons into valuable by-products.

Flex-Fuel Internal Combustion Engine
In the figure above, it is very noticeable that throughout all the life stages of the life cycle of the flex fuel engine, the fuel production phase has the highest global warming potential. The highest contributing sub-sector is the “Basic Organic Chemical Manufacturing” sector which emits large amounts of CO2 and N2O to process and refine ethanol. The farming industry also uses large amounts of diesel powered machinery, which contribute to the overall GWP during the fuel production phase. Furthermore, the advantage of using a flex fuel engine is visible through the low global warming potential during the use phase. There are significantly less emissions during this phase since E85 burns more cleanly due to its high number of oxygen atoms.

In addition, in the figure above, shows that the energy use during the operation of the vehicle throughout its life cycle is very large. This fact can be explained through the lower energy density of E85 than gasoline and also its lower MPG. This causes frequent refuelling which, in turn, causes more energy consumption. Moreover, the energy use during the fuel production phase is also high as a result of intensive processes, such as distilling, which heavily relies on electricity that is generated from coal, which is the source of most emissions that cause a high global warming potential.

Hydrogen Fuel Cell
From the analysis, see figure above, it is apparent that fuel production stage of the fuel cell life cycle constitutes most of the total global warming potential. Furthermore, it is quoted that in central steam methane reforming stations the mass of CO2 produced during the production of the hydrogen is twice the mass of hydrogen produced. On the other hand, the global warming potential during the use phase is shown nil, reflecting the zero tail pipe emission characteristic of a fuel cell propulsion system.

As shown in the figure above, it is noticeable that the fuel production and use phase consume a large amount of energy. The steam methane reforming (SMR) process includes a reformation of natural gas, two stages of water gas shift reactions at a very high temperature, and repetitive purifications. The SMR is an energy intensive process and this explains the highenergy consumption estimation from EIOLCA. Furthermore, relatively low 22% power plant-to-wheel efficiency of the hydrogen fuel requires a lot of energy input to operate.

Gasoline Internal Combustion Engine
The SLCA matrix indicates that delivery and end of life are the two most environmentally friendly stages of the engine’s life cycle. This is mainly due to the very low solid and liquid residues that result from this stage in delivery and the ability to recycle almost all the components in the engine. On the other hand, pre-manufacturing and manufacturing of the engine seem to have the most environmental impact. This results from the relatively high-energy use and residues in these processes. Looking at the different inputs and outputs of the life cycle, it is observed that energy use and gaseous residues have the most impact on the environment which is caused by the energy intensive processes and the large amounts of air pollutants in fuel production, engine manufacturing and use phase of the engine.

Flex-Fuel Internal Combustion Engine
It is visible in the SLCA Matrix shown in the middle of the page that for the flex fuel engine, the material choice column has overall the highest score, meaning that the use of virgin material is minimized and the amount of recycled materials is maximized. The column with the lowest score is the energy use and this can be reflected through the energy intensive processes of extracting and manufacturing the engine. Frequent refueling during the use phase is also an issue during the use phase. The rows with the lowest scores are the pre-manufacturing and the manufacturing life stages due to the high amount of energy input and also large number of residues being created.

Hydrogen Fuel Cell
The hydrogen fuel cell may be conceived as a zero emission automobile propulsion system, however when entire life cycle of the vehicle is considered, it shows that it in fact does contributes to green house gases and air pollution. From the SLCA matrix, it is shown that premanufacturing and manufacturing stage has the most negative impact on the environment. On the other hand, the use phase of the vehicle has a relatively small impact on the environment due to the non-combustible nature of a fuel cell.


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Design for the Environment/Disposal of Non-Recyclables

Non-recyclable waste are solid waste which are not processed nor reclaimed by a city's waste management system. The disposal of these materials are a rising concern in many parts of the developed world where environmental alertness has been a rising trend; This a particularly important issue in the City of Toronto where a long-term waste management solution is not well defined.

For nearly two decades, the Keele Valley Landfill in Maple, Ontario has been the main landfill site for the City of Toronto, after having received more than 26 million tonnes of waste and reaching maximum capacity, it closed in 2002 . Since then, Toronto has been sending its waste across the boarder to Carleton Farms Landfill in Michigan. From January to August 2007, an average of 2070 tonnes of solid waste per day was redirected from Toronto to Michigan . In April 2007, the City of Toronto acquired the Green Lane Landfill Site southwest of London, Ontario in anticipation of the contract expiration with Carleton Farms Landfill .

However, the acquisition of the Green Lane Landfill site has several major environmental, economic and social-political repercussions . In this article, the environmental, economical and societal impacts of Landfilling will be compared to Waste Incineration and Plasma Arc Gasification in hopes of finding a suitable alternative for Toronto's waste disposal of non-recyclable waste.

Carleton Farms Landfill
The Carleton Farms Landfill (Sumpter Energy Associates) in Sumpter, Michigan is currently the reciepient of almost 700000 tonnes of waste per year from the City of Toronto. This facility houses a methane recovery system to recapture and use landfill gases as an energy source; In 1998 when plant operations began, five Caterpillar 3516 engine generator produced 4 megawatts of power, In  1999, two more generators sets were added expanding power generation to 5.6 megawatts. In 2001, a third set of generators were added, boosting power production to 6.4 megawatts - approximately equivalent to the demands of 7000 homes and businesses .

Landfills are not aesthetically pleasing to surrounding communities due to strong odours emissions as well as noise created by the trucks; they also release excessive amounts of Methane, a Greenhouse Gas that is damaging to the environment.

Functional Analysis
The primary function of the landfill, as defined by the Canadian Oxford Dictionary is "the disposal of refuse by burying it under layers of earth.". This implies a permanent solution to the issue of what is to be done with the waste. Toronto views landfills as a solution for permanently handling the City’s current waste production, but it is not sustainable as a long-term solution.

As said before, one benefit of using landfill waste disposal is the ability to produce electricity for sale back onto the public Power grid. The methane gas which escapes from far under the surface of the landfill is collected via an intricate system of closely monitored pipes and sent to one of several engine generator sets run by Sumpter Energy Associates located at the Carleton Farms Landfill site. It was recently published that this generating station is capable of producing 6.4 MW of power, with production expecting to be up to 12 MW in the future.

Economic Input/Output Lifecycle Assessment
The EIOLCA displays a diverse view of the environmental impacts which an alternative may have on a society. In carrying out this analysis, it was necessary to determine all of the economic inputs that are made towards the five lifecycle stages of the landfill.

The most significant of these costs is incurred in transporting the garbage from Toronto to Michigan, and then returning the trucks back to Toronto again to collect the next shipment. Aside from being the largest annual cost associated with landfilling Toronto’s non-recyclables in Michigan, this is also one of the greatest contributors to the environmental unfriendliness of this waste handling alternative. At a cost of ~$3.8 million for the diesel required to make this trip, trucking the trash to Michigan creates 8300 MTCO2E (Metric Tonnes of Carbon Dioxide Equivalent) of greenhouse gases, 1020 kg of releases, and uses 93.1 TJ of energy.

In order to reduce the environmental impact of the waste management system, Toronto must adopt an alternative near or around the Greater Toronto Area to save on fuel consumption. It is for this reason alone that incineration and plasma gasification are very plausible alternatives to landfilling.

Also vital to the successful operation of any modern day landfill is the methane gas collection system. Not only does this entity ensure that the landfill meets local environmental regulations, it is also a means for creating revenue for the private corporations who have a vested interest in the landfill as a money making tool. The total environmental impact of the methane collection system, considering its implementation as well as use, is tallied at 5000 MTCO2E, 14000 kg of releases, and 16000 TJ of energy usage. These results are perhaps skewed due to the EIOLCA model’s inability to handle this economic activity entirely in one sector. As such, this system was grouped into the Water, Sewage, and Other Systems sector, which deals predominantly with water treatment. For the scope of this article, however, the activities in this sector are assumed to be analogous to those related to the operation and maintenance of the methane collection system.

Any “engineered landfill” is one which contains a sophisticated arrangement of materials lining the very bottom of the landfill. The purpose of this is to prevent Leachates from escaping into the Groundwater running beneath the landfill. Given that the State of Michigan has published very little on its regulations and standards, other standards were used to gauge what is generally considered typical - This includes a minimum hydraulic conductivity of 10-8 cm/s. A generally accepted way of achieving this is to use a landfill comprised of clay, a plastic liner, and finally a layer of sand . The plastic in this case is assumed to be 2mm low-density polyethylene. The combined effects of the three layers of the liner are 2600 MTCO2E, 650 kg of releases, and 40 TJ of energy.

Also of interest is the toll that the liner takes in decreasing the rating of this waste disposal method. A much better and more environmentally friendly alternative would be to use recycled automobile tires as a primary component of the leachate collection system. Tests have demonstrated that high quality (HQ) shredded tires have average Hydraulic Conductivities spanning a range from 0.67 to 13.4 cm/s. Given that the standard for Toronto’s Keele Valley Landfill was maintained at a strict minimum of 10-8 cm/s, recycled tires are not a be-all and end-all solution, however would provide great relief to the amount of clay that is currently required to line a site. At a GWP MTCO2E of 2280, this is the third highest contributor to the landfilling process as a whole, and therefore it would be highly advantageous to be able to reduce this impact to the environment. Upon consideration of these, the most predominant contributors to a landfill’s pollution, it becomes much clearer why alternatives must be investigated. A landfill not only is a place of concentrated gas releases, but also triggers economic activity in many other highly polluting sectors. An ideal solution is perhaps one which utilizes the garbage more effectively, and more appropriately handles it before being left for its final resting place.

Streamlined Lifecycle Assessment
The Streamlined Lifecycle Analysis offers an alternative method of comparing alternatives based on a relative ranking of various factors throughout the product’s life. In comparing SLCA rankings of Carleton Farms Landfill to incineration and plasma gasification, landfill ranks the lowest. This owes in large part to the high energy usage required in the primary stage. This stage includes shipping the garbage to Michigan, as well as operation of the methane gas collection system and daily garbage collection and on-site compacting.

Also contributing heavily to the low score are the solid and liquid residues associated with the primary and secondary process operations. These results parallel those demonstrated in the EIOLCA, which shows consistency as well as reaffirms the accuracy of the results demonstrated here.

Unlike the end of life stage of an incineration plant or a gasification plant, the end of life of a landfill does not equate to the cessation of different releases. Many solid, liquid, and gaseous residues continue to be emitted. For this reason the total End of Life stage of the landfill score a three.

To further increase this rating, it would be most beneficial to reduce the energy inputs required to perform the primary process operations. Mainly the garbage transport from Toronto to Michigan.

Societal Analysis
A landfill’s impact on society is apparent immediately upon entering into its vicinity. As Michigan residents have complained, the smell of Toronto trash fills the air as soon as the trucks start to come in for the day. This dilemma is inherent in operating a landfill, and little may be done to contain the problem. Although the methane collection system is a step in the right direction and trucks are sealed to contain odorants, the trash is still crossing the border, and continues to have noticeable impacts on residents of Michigan and southern Ontario Another issue of the particular system utilized by Toronto is that the waste matter must be transported such a long distance before arrival at its final destination. This has Michigan officials exasperated because of the added traffic creating congestion and adding extra pollutants to their air.

Landfills also affect the property values of nearby homes and businesses. A recent study on the issue in Toronto indicates that “larger landfills have greater adverse impacts on property values than smaller landfills, implying consumers perceive ... differences in external costs.” This may also be a function of the amount of waste that the fill handles, with a larger one being perceived as a more pronounced nuisance. Also important to note is that the larger a landfill, the longer it is likely to be open for, and this will also hinder the ability of the society to develop in that area.

In general, landfills have a significant impact on society, although once closed, these impacts become hardly noticeable and therefore make it a humble contender as a method for dealing with the disposal of non-recyclable materials.

Cost Analysis
For the purposes of this section, all costs are calculated on an annual basis. Therefore, one-time costs are divided by the thirty year expected useful life of the landfill. As an example, we shall consider the end of life costs of the landfill. These are one time costs, and their total is $10,500,000. This number was divided by the thirty years, and then the time value of money was accounted for, thus determining the equivalent payment in 2008 dollars required annually while accounting for the rate of inflation.

The costs of a landfill derives from much more than the immediate monetary considerations; much of the costs incurred by a landfill comes in its later stages of life. The Mackinac Centre for Public Policy suggests that companies invest between $750,000 and $1 million per acre to meet state and federally imposed regulations

The equivalent annual cost for operation of a landfill is approximately $9 million. Once again this cost is highlighted by the estimated $2 million required for operation and maintenance of the methane collection system. Other operational costs are, for the most part, limited to diesel fuel consumption and electricity consumption. Given that this landfill is so large, the costs associated with it are quite significant. However, when amortized over several years they become much more manageable figures.

Waste Incineration
Waste incineration is the removal of waste via combustion using high temperature furnaces. Modern waste incinerator utilizes Cogeneration as well as Waste to Energy (WtE) technologies where electricity is produced from the incineration process. In our discussion, a WtE incineration will be assumed for the City of Toronto.

To begin the incineration process, the waste is brought into the facility via trucks to the tipping floor where large and recyclable objects are removed by the workers . Waste that is now suitable for incineration is then loaded into a two-stage incinerator where it is combusted. Gases released from the primary combustion process are transferred to a second stage chamber where they are further refined to produce large amounts of heat. This heat is captured using a recovery boiler that produces steam which in turn drives a turbine to produce electricity . During combustion of the waste, ash is produced and is collected from the incinerator and transferred to a landfill .

The use of waste incineration is discouraged by environmentalists due to high CO2, Dioxin and Furan emissions. Steam vapour from plant smokestacks is also an aesthetics concern to some.

Functional Analysis
Incineration waste disposal is not only the simple task of burning garbage, major considerations must be made when choosing the type of incineration facility to be built since valuable energy can be harvested through the waste combustion process. In this article, an Energy from Waste (EFW) or Waste to Energy (WtE) facility will be assumed for the City of Toronto.

In the WtE waste incineration process, garbage which had been screened for any large objects are combusted at high temperatures; Any ash solids remaining from combustion are then collected for landfilling while fuel gases from incinerating waste are further combusted to heat boilers. The steam produced from the boilers are then used to drive turbines to produce electricity which can be used internally at the facility or sold back to energy providers.

Modern incineration facilities are outfitted with emission filtering systems and cleaners to reduce the pollutants that are released into the air. These systems greatly reduce the NOx, SO2, particulates, etc, released into the environment. Unlike the landfilling of untreated waste, incineration greatly reduces the volume of the waste produced, resulting in a more efficient use of landfills (only the incineration ash is landfilled).

Cost Analysis
Based on estimates from 2006, the City of Toronto had produced about 1 million tonnes of waste where 70% of that value were non-recyclables. As the City has proposed to diverge 60% - 70% of the total waste produced to be recycled, the cost analysis was performed assuming 400,000 tonnes of waste was to be incinerated in the future.

Estimation of plant/facility costs were based on the proposal of an incineration facility in the Durham/York Region. The estimated total construction cost to erect a plant capable of processing 400,000 tonnes of waste per year was $250 million. The operation cost of a waste incineration plant is high compared to a landfill, working out to be approximately $76 per tonne of waste. This gap can be reduced by accounting for the elimination of the transport fees to the Michigan landfill from Toronto.

A major cost benefit of waste incineration is the resale of power generated by the facility, WtE incineration plants generate approximately $12 million of power per year.

Societal Analysis
The societal impacts of a waste incinerator are profound. Waste incinerators smokestacks are not very visually appealing to the neighbours of such a facility, and their downwind odour emissions are not very pleasing. As such, incineration plants will have to be built outside of the City of Toronto. But as the city continues to expand, location finding becomes more and more difficult, it is not easy to find a convenient site for such a plant that is also isolated from any large communities nearby since the public tends speaks out against the use of waste incinerators.

Streamlined Lifecycle Assessment
Even though the streamline life cycle assessment (SLCA) does not look into the alternative of incineration in depth, it does provide a quick way for the ranking of different waste disposal alternatives. On the SLCA, Incineration scored lower than Plasma-Gasification and higher than landfilling.

The SLCA also provides a way to identify an alternative's shortcomings and benefits in each life stage. For the incinerator, high gaseous emissions and high energy use resulted in an general overall low score for the incineration alternative. This is because high temperatures must be maintained to allow for complete combustion of the waste to occur, and this requires a lot of energy. Also, the combustion of garbage emits large amounts of pollutants, thus a low score for the gaseous resided is rewarded.

Economic Input/Output Lifecycle Assessment
The waste management sector is a major user of energy from many different sources. This value is comparable to the low score awarded in the SLCA. Also the amount of carbon dioxide (CO2) and other Greenhouse Gases released by the waste management sector is very high. The most important figure found by completing this assessment was the Global Warming Potential (GWP). The waste management sector contributed to more than 93% of the total GWP, where it releases 4,390,000 metric tonnes of CO2 equivalent.

The values found in the EIO-LCA corresponded with similar low scores in the SLCA. This help to reinforce the understanding of the incineration process and how it contributes positively and/or negatively to our environment. But because there is no way to compile a fully comprehensive EIO-LCA it is hard to decide definitively whether incineration is the best alternative to land filling.

Plasma Arc Gasification
Similar to WtE incineration, Plasma Arc Gasification takes advantage of the abundance of potential energy in garbage; Plasma Gasification is an incineration process with an excellent energy recovery ability, it makes use of high electrical energy and high temperatures to break down waste into organic gases and inorganic solids . If accurately managed, processing waste at plasm temperatures can very well be a greener solution to traditional incineration and landfills. Although still in its early development stage , Plasma incineration has already shown to have many advantages over traditional forms of waste removal.

The main benefits of Plasma Arc Gasification is its ability to convert all of its gaseous by-products into electricity and its solid by-products into construction materials, creating a nearly zero-emission conversion process. However, as we will see later, Plasma Gasification is not a flawless solution.

Technical Analysis
The largest benefit of using Plasma Gas Gasification is the reduction of environmental impacts. By separating waste matter into individual ions at very high temperatures, there is minimal formation of solid residues - about 60 times less than a conventional incinerator. In addition, instead of creating ash as a solid by-product, there is the formation of valuable metals and Slag; Furthermore, plasma incineration produces a beneficial gas product known as Syngas which can be refined into a fuel to produce energy.

On average, a Plasma Incinerator plant can burn 75,000 tonnes of municipal waste per year, generating a total of 7.9 MW of power (3.6 MW to the grid).

Economic Input/Output Lifecycle Assessment
The air polluting outputs from a Plasma Gasification Plant are relatively low because the gasification process does not involve combustion, thus the process does not generate as much pollution as a regular incineration plant. However, according to the EIOLCA, the “Waste management and remediation services” sector contributes to much of the Methane releases from the plant - accounting for about 33100 metric tons a year of CH4. However, syngas is created from synthesizing CH4 and H2O, according to this equation:

 * CH4 + H2O → CO + 3 H2

Negating the effects of much of the methane release.

A Plasma Arc Gasification plant that processes 75000 tonnes of waste releases 35800 kg (35.8 tonnes) of toxic waste a year - less than 0.001% of the total waste processed.

Streamlined Lifecycle Assessment
The chief benefit of Plasma Gasification is its ability to provide self-sustaining power while supplying power to the grid, as such, the energy sector of the SLCA for Plasma Gasification process receives a perfect score. Another perfect score was given to the liquid residue section, due to the extreme heat of the process, there is no possibility of liquid formation. Also, most of the solid and gas residue generated by a plasma incinerator are beneficial.

The plant maintenance process is very energy consuming due to the strict operating standards for a Plasma Gasification plant, a careful filtering process is required to purify the solid and gaseous byproducts in order to minimize the toxic release into the environment. Thus, the energy use sector for the maintenance life stage has a relatively low score, but due to this careful filtering process, an insignificant amount of gases and solids are released into the environment, granting a perfect score for the gas and solid residue sectors.

Cost Analysis
Recent studies claimed that:

Compared to a landfill which charges only around $35 per tonne of waste, it would cost about $172, per tonne, to dispose garbage at a plasma incineration plant.

Plasma Gasification is not a cheap alternative to traditional landfilling or incineration. The maintenance costs of a plant that incinerate 75000 tonnes of waste is almost $150 per tonne, such a plant will also require an additional $115 dollars for the collection and transportation of the waste, plus roughly $25 per tonne for miscellaneous and overhead costs. This would results in an average of $290 per tonne of Municipal Solid Waste equivalent to $21.75 million per year of operational costs.

For the City of Toronto, a Plasma Arc Gasification plant will cost $1.452 billion (at 5% interest, compounded yearly, over 40 years) to build, operate and decommission at the end of 40 years. The accumulated revenues from to electricity and slag sales will recover $176.6 million. Thus to break even, the plant must charge an extra $355 per tonne of waste. Such expenses make it almost impossible for a city to implement Plasma Arc Gasification as a waste disposing alternative. This is the greatest disadvantage of a Plasma Incineration energy plant. However, with further upscaling of this technology and the rising electricity prices; Plasma technology may become affordable and feasible.

Societal Analysis
A Plasma Gasification plant has the lowest environmental impact out of all three alternatives. Site location for the plant is also quite easy due to the small size of these plants. This alternative has the same societal impact on neighbouring communities as traditional incinerators.

Recommendations
Incineration and Plasma Gasification are just two of the many countless alternative solutions to landfills. When designing for the environment, the most important factor is the impact that a design has on the environment; it was determined from above that plasma gasification had the most potential because it can efficiently remove waste and generate energy at the same time, however, it was also determined that plasma gasification is also the most expensive option, rendering it ineffective by current standards.

Comparing between landfills and incinerators, it can be seen that landfills have less environmental impacts throughout its implementation and operation stage, however, its impact on the environment continues long after its end of life - Whereas an incinerator’s effects on the environment halts almost immediately after its end of life.

The City of Toronto should continue to use the Carleton Farms Landfill until the end of the contract, while using the time between then and now to research on a more efficient Plasma Gasification process, since in order for Plasma Gasification to be adopted, more research on Gasification technology must be done. The city should avoid building an incinerator since it does not make sense to build an incinerator now; just to render it obsolete once a plasma gasification plant comes about.


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User talk:KChan

Hello, welcome around here. I hope you succeed in your learning goals. Below more info about Wikiversity, Erkan Yilmaz uses the Wikiversity:Chat (try) 19:23, 4 April 2008 (UTC)

Welcome
Hello KChan, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
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User talk:Elmira kalali

Hello, welcome around here. I hope you succeed in your learning goals. Below more info about Wikiversity, Erkan Yilmaz uses the Wikiversity:Chat (try) 19:24, 4 April 2008 (UTC)

Welcome
Hello Elmira kalali, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
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And don't forget to explore Wikiversity with the links to your left. Be bold, and see you around Wikiversity! Erkan Yilmaz uses the Wikiversity:Chat (try) 19:24, 4 April 2008 (UTC)

short wiki link
A link to an article in english wikipedia is writting  alternativ text  but not  alternative text . Thanks. Crochet.david.bot 18:17, 7 April 2008 (UTC)
 * Ok, excuse me, I have not seen you did thereafter.Crochet.david.bot 18:22, 7 April 2008 (UTC)

Copyright problem with Image:ICE.JPG
The image is copyright DaimlerChrysler --mikeu talk 17:50, 11 April 2008 (UTC)

Also, the image Image:Flex.JPG --mikeu talk 17:55, 11 April 2008 (UTC)

title: User talk:Elmira kalali


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User:Aj00200

See my Wikipedia userpage. That one is updated, and also see the Geek Fact of the Month on that page. My Wikipedia Talk Page

title: User:Aj00200


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User talk:Aj00200

Hello, welcome around here. I hope you succeed in your learning goals. Below more info about Wikiversity, Erkan Yilmaz uses the Wikiversity:Chat (try) 20:12, 4 April 2008 (UTC)

Welcome
Hello Aj00200, and welcome to Wikiversity! If you need help, feel free to visit my talk page, or contact us and ask questions. After you leave a comment on a talk page, remember to sign and date; it helps everyone follow the threads of the discussion. The signature icon in the edit window makes it simple. To get started, you may
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title: User talk:Aj00200