report on"full life cycle assessment for a plastic and glass product"

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Page 1: Report on"Full life cycle assessment for a plastic and glass product"

Report on"Full life cycle assessment for a plastic and glass product"RN-1108

Social_hack team

GR 04

Neha RoyHindustan University

GR 04

Page 2: Report on"Full life cycle assessment for a plastic and glass product"

This report gives a detailed information on full life cycle assessment for a plastic and glass product. It also deals about the various environmental effects of a plastic and glass product when dumped improperly.

PLASTICS

Plastic products are very common in use and they are made up of long chains of synthetic and semi-synthetic organic polymers. They are usually synthetic, most commonly derived from

petrochemicals, but many are partially natural. Most plastics contain other organic or inorganic

compounds blended in. The amount of additives ranges from zero percentage for polymers used to wrap

foods to more than 50% for certain electronic applications. The average content of additives is 20% by

weight of the polymer. Many plastics contain fillers, relatively inert and inexpensive materials that make

the product cheaper by weight. Plastics are usually classified by their chemical structure of the polymer's

backbone and side chains.

TYPES

There are two types of plastics: thermoplastics and thermosetting polymers. Thermoplastics are the

plastics that do not undergo chemical change in their composition when heated and can be molded again

and again. Examples include polyethylene, polypropylene, polystyrene and polyvinyl chloride. Common

thermoplastics range from 20,000 to 500,000 amu, while thermosets are assumed to have infinite

molecular weight. These chains are made up of many repeating molecular units, known as repeat units,

derived from monomers; each polymer chain will have several thousand repeating units.

Thermosets can melt and take shape once; after they have solidified, they stay solid. In the thermosetting

process, a chemical reaction occurs that is irreversible. The vulcanization of rubber is a thermosetting

process. Before heating with sulfur, the polyisoprene is a tacky, slightly runny material, but after

vulcanization the product is rigid and non-tacky.

Knowing the code for a particular product, consumers can then inform themselves of the characteristics of the plastic and the risks

of using that product.

Polyethylene terephthalate (PET or PETE) – Used in soft drink, juice,water, beer, mouthwash, peanut butter, salad dressing, detergent and

cleaner containers. May leach antimony trioxide. Workers exposed to antimony trioxide for long periods of time have exhibited respiratory and skin irritation; among female workers, increased incidence of menstrual problems and miscarriage; their children exhibited slower development in the first twelve months of life. The longer a liquid is left in such a container the greater the potential for release of antimony into the liquid. Considered a relatively safe plastic. Our research on risks associated with this type of plastic is ongoing.

High density polyethylene (HDPE) – Used in opaque milk, water, and juice containers, bleach, detergent and shampoo bottles, garbage bags,

Page 3: Report on"Full life cycle assessment for a plastic and glass product"

yogurt and margarine tubs, cereal box liners. Considered a 'safer' plastic.Our research on risks associated with this type of plastic is ongoing.Polyvinyl chloride (V or Vinyl or PVC) – Used in toys, clear food and non-food packaging (e.g., cling wrap), some squeeze bottles, shampoo

bottles, cooking oil and peanut butter jars, detergent and window cleaner bottles, shower curtains, medical tubing, and numerous construction products (e.g., pipes, siding). PVC has been described as one of the most hazardous consumer products ever created. Leaches di(2-ethylhexyl) phthalate (DEHP) or butyl benzyl phthalate (BBzP), depending on which is used as the plasticizer or softener (usually DEHP). DEHP and BBzP are endocrine disruptors mimicking the female hormone estrogen; have beenstrongly linked to asthma and allergic symptoms in children; may cause certain types of cancer; linked to negative effects on the liver, kidney, spleen, bone formation and body weight. In Europe, DEHP and BBzP and other dangerous pthalates have been banned from use in plastic toys for children under three since 1999. Not so elsewhere, including Canada and the United States.

Low density polyethylene (LDPE) – Used in grocery store, dry cleaning, bread and frozen food bags, most plastic wraps, squeezable

bottles (honey, mustard). Considered a 'safer' plastic. Our research on risks associated with this type of plastic is ongoing.Polypropylene (PP) – Used in ketchup bottles, yogurt and margarine tubs, medecine and syrup bottles, straws, Rubbermaid and other opaque

plastic containers, including baby bottles. Considered a 'safer' plastic. Our research on risks associated with this type of plastic is ongoing.

Polystyrene (PS) – Used in Styrofoam containers, egg cartons, disposable cups and bowls, take-out food containers, plastic cutlery,

compact disc cases. Leaches styrene, which is an endocrine disruptor mimicking the female hormone estrogen, and thus has the potential to cause reproductive and developmental problems; long-term exposure by workers has shown brain and nervous system effects; adverse effects on red blood cells, liver, kidneys and stomach in animal studies. Also present in secondhand cigarette smoke, off-gassing of building materials, car exhaust and possibly drinking water. Styrene migrates significantly from polystyrene containers into the container's contents when oily foods are heated in such

containers.Other – This is a catch-all category that includes anything that does not interpreting this category because it includes polycarbonate - a

dangerous plastic - but it also includes the new, safer, biodegradable bio-based plastics made from renewable resources such as corn and potato starch, and sugar cane. Polycarbonate is used in many plastic baby bottles, clear plastic “sippy” cups, sports water bottles, three and five gallon large water storage containers, metal food can liners, some juice and ketchup containers, compact discs, cell phones, computers. Polycarbonate

Page 4: Report on"Full life cycle assessment for a plastic and glass product"

leaches Bisphenol A (some effects described above), and numerous studies have indicated a wide array of possible adverse effects from low-level exposure to Bisphenol A: chromosome damage in female ovaries, decreased sperm production in males, early onset of puberty, various behavioural changes, altered immune function, and sex reversal in frogs.

Biodegradability

Biodegradable plastics break down (degrade) upon exposure to sunlight (e.g., ultra-violet radiation), water or dampness, bacteria, enzymes, wind abrasion, and in some instances, rodent, pest, or insect attack are also included as forms of biodegradation or environmental degradation. Some modes of degradation require that the plastic be exposed at the surface, whereas other modes will only be effective if certain conditions exist in landfill or composting systems. Starch powder has been mixed with plastic as a filler to allow it to degrade more easily, but it still does not lead to complete breakdown of the plastic. Some researchers have actually genetically engineered bacteria that synthesize a completely biodegradable plastic, but this material, such as Biopol, is expensive at present. Companies have made biodegradable additives to enhance the biodegradation of plastics.

Environmental hazards due to plastic are:

1. Littering of the landfills and other open spaces with plastic garbage becomes unhygienic and ugly,

2. Littering of plastics in the form of plastic bags causes blocking of the cities, municipalities sewerage systems leads to spreading of water borne diseases and increasing the cost of sewage maintenance systems.

3. Soil fertility is also affected due to plastic material as it forms part of manure remaining in the soil for years without natural degradation.

4. Death of animals due to suffocation, stomach and intestine related diseases is a common feature mostly in developing economies due to improper disposal of plastic food bags that are eaten by these animals.

5. Plastic waste is finding its way into the rivers, oceans and seas of the world due to which the rich marine life is facing serious health hazards. Marine animals like fish, sea birds, otters and other marine species are swallowing these plastic wastes as food items that are leading to a premature death of these precious marine species.

6. Pollution of environment by industries manufacturing the plastic materials is another serious issue that is facing the environmentalists and the governments globally. The manufacturers of plastic materials are polluting the environment by disposing of the plastic waste and chemicals used in the process of manufacturing plastic material into nearby water channels and open

Page 5: Report on"Full life cycle assessment for a plastic and glass product"

spaces thereby causing health hazards as well as environmental pollution in a vast area.

The laws requiring these manufactures to install anti-pollution machinery at their premises is not being strictly adhered to by these people.

Biodegradable plastic

Some plastics have been engineered to biodegrade reasonably quickly – and here’s the important part – in a large composting facility that intentionally accelerates biodegradation in a highly controlled environment using copious air, water and light. These plastics also will break down eventually if left alone in the environment – but much more slowly since the environment does not “intentionally accelerate” biodegradation. However, similar to other biodegradable materials, they likely will not break down in modern landfills that basically store waste and are designed to retard biodegradation.

So … biodegradability of plastics depends largely on the type of plastic and where it ends up.

Approximated time for compounds to biodegrade in a marine environment

Product Time to Biodegrade

Plastic coated milk carton 5 years

Glass bottles Undetermined (forever)

Plastic bags 10–20 years

Soft plastic (bottle) 100 years

Hard plastic (bottle cap) 400 year

GLASS

The most familiar type of glass, used for centuries in windows and drinking vessels, is soda-lime glass, composed of about 75% Silicon dioxide (SiO2) plus sodium oxide (Na2O) from soda ash, lime (CaO), and several minor additives. Often, the term glass is used in a restricted sense to refer to this specific u In this wider sense, glasses can be made of quite different classes of materials: metallic alloys, ionic melts, aqueous solutions, molecular liquids, and polymers. For many applications (bottles, eyewear) polymer glasses (acrylic glass, polycarbonate, polyethylene terephthalate) are a lighter alternative to traditional silica glasses.se.

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Glass is a mixture having no definite boiling of freezing points. It is also called a super cooled liquid. Chemically, most glasses are silicates. It is transparent and not affected by chemicals. It can be moulded into any shape. The ingredients for making glass are:-

1. Limestone (CaCO3),2. Soda ash (Na2CO3), and3. Sand (SiO2)

Manufacture of glass

The manufacture of glass involves the following steps:

1. Limestone, sand and soda ash are mixed and poured into a tank furnace. Tank furnace looks like a small swimming pool. It is very hot (about 17000C). It is shallow at one end and deep at the other.

2. The raw material moves slowly towards the deeper end. Silica melts at a very high temperature. In order to lower its melting point, soda ash is added. Thus, energy is saved and a low cost is incurred in the glass-making process.

3. Due to the presence of limestone, glass becomes insoluble in water.

4. As the raw material melts, a clear jelly-like substance is formed; this takes about a week’s time.

5. During this time bubbles of CO2 gas escape and some of the raw material slowly changes into a mixture of silicates.

6. The following reactions take place inside the furnace.

7. The clear jelly-like substance on cooling sets to form glass. This is known as soda-lime glass.

Types of glass

There are nine types of glass according to the minor additions and variations in the ingredients used and according to the methods of manufacturing. The different types of glasses are different in their properties and uses.

1. Soda glass or soda-lime glass:

It is the most common variety of glass. It is prepared by heating sodium carbonate and silica. It is used for making windowpanes, tableware, bottles and bulbs.

2. Coloured glass:

Page 7: Report on"Full life cycle assessment for a plastic and glass product"

Small amounts of metallic oxides are mixed with the hot molten mixture of sand, sodium carbonate and limestone. The desired colour determines the choice of the metallic oxide to be added, as different metallic oxides give different colours to the glass.

Coloured glass is much in demand. It is used for decorating walls, making sunglasses, and for making light signals for automobiles, trains and aeroplanes.

3. Plate glass:

Plate glass is thicker than ordinary glass. It has a very smooth surface. It is made by floating a layer of molten glass over a layer of molten tin. It is used in shop windows and doors.

4. Safety glass:

It can also be called shatterproof glass. It is made by placing a sheet of plastic such ascelluloid between sheets of glass. The special quality of this glass is that in case of breakage the broken pieces stick to the plastic and do not fly off. You must have noticed a broken window-pane of a bus or a car still in its place. It is used in automobiles. It is also used for making bulletproof screens.

5. Laminated glass:

It can also be called bulletproof glass. Several layers of safety glass are bound together with a transparent adhesive. The larger the number of layers used the greater is the strength of the glass. It is stronger than safety glass. It is used in aeroplanes and windshields of cars.

6. Optical glass:

Optical glass is softer than any other glass. It is clear and transparent. Potassium and lead silicates are used in making optical glass. It is also called flint glass. The main use of flint glass is in the manufacture of lenses, prisms and other optical instruments.

7. Pyrex glass:

Pyrex glass is highly heat resistant. In ordinary glass, silica is the main constituent. In pyrex glass some of the silica is replaced by boron oxide. Boron oxide expands very little when heated, thus, pyrex glass does not crack on strong heating. Pyrex glass is also called borosilicate glass. It has a high melting point and is resistant to many chemicals. Laboratory equipment and ovenware are made of pyrex glass.

8. Photo-chromatic glass:

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Photochromatic glass acquires a darker shade when exposed to bright light and returns to its original lighter shade in dim light. This happens because silver iodinde is added to this glass. (silver iodide gets coloured with the intensity of light.)

9. Lead crystal glass:

Lead crystal glass has high refractive index, and so has the maximum brilliance. It sparkles and is used for high quality art objects and for expensive glassware. It is also called cut glass because the surface of the glass objects is often cut into decorative patterns to reflect light. In order to increase the refractive index, lead oxide is used as flux in crystal glass, therefore it is also called lead crystal glass.

The major disadvantage of ordinary glass is that it is brittle. It cracks when subjected to sudden changes of temperature. When the glass has been moulded into a finished article, it is cooled very slowly to prevent brittleness. The process in which a finished glass article is cooled slowly is called annealing.

As an architectural element, glass has become the quintessential product for your home or building.

Designers play a key role in the selection and application of glass and with the wide range of applications including concertina doors, louvre windows, kitchen splashbacks and frameless glass showscreens, how glass can be used is only limited by your imagination.

Glass plays a vital role in the internal and external function and design of your project.

Assessment of Environmental Impacts of glass manufacturing and benefits of glass products

As an energy-intensive manufacturing process, it is no surprise that the primary environmental impacts associated to float glass manufacturing are the Global Warming Potential (mainly due to CO2 emissions from raw materials and fuels use) and Primary Energy Demand (for which the upstream production of energy, in particular natural gas, is the main contribution).

That being said, it must be borne in mind that end-products made of float glass provide tremendous benefits in terms of CO2 emissions reduction in their different usages and in particular when used in energy-efficient windows and facades in buildings. Savings of more than 100 million tonnes of CO2 could be achieved annually if Europe's buildings were fitted with advanced energy saving glass (more information here).

For this reason, full life-cycle analyses which account for these energy-saving benefits are all the more important. Based on this LCI work and independent studies already available, one can be confident that full LCA analysis would reveal that glass products

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are energy-saving products as savings realized by the products throughout their life largely offset the CO2 emitted during production.

To Glass for Europe's views, the full life-cycle analysis of products should be favored whenever possible as self-limiting analysis to manufacturing and carbon content would fail in providing a true picture of products' environmental performances. For instance, the production of a single glazing window will always require less energy than that of an energy-efficient double or triple glazed windows, whereas the latter are unquestionably more environmental-friendly.

For these reasons, Glass for Europe continues its work on life-cycle analysis and will make sure that flat glass is seen as what it is: an energy-saving product.

In particular, Glass for Europe is currently extending its work on life-cycle analysis to assess the additional impacts associated to the off-line coating of float glass used in building applications.

Page 10: Report on"Full life cycle assessment for a plastic and glass product"

LIFE CYCLE OF GLASS

It can't be degraded by biological means.

CONCLUSION:

Thus it can be concluded that plastic products are non-biodegradable mostly but now- a-days bio-degradable plastics are also available with high costs and rates. It takes time also for degradation.

As far as glass products are considered ,they are not biodegradable, they can even take lifetime to degrade, they can be changed from one form to another simply.