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Explore the quantities, uses, and benefits of plastics in various industries, including transportation, medicine, electronics, construction, and packaging. Learn about the impact of plastic waste on the environment and the importance of recycling.
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Polymer & Plastic waste and Recycling Dr. Manohar Singh Saini Director, Guru Nanak Dev Engg. College, Ludhiana January 3, 2012
A Global Look at Plastics: Quantities, Uses and Benefits Plastic products improve our daily lives and have made vast improvements in areas such as: • Transportation - Automotive, Aerospace, Space Exploration • Medicines - helping us all live longer, healthier lives • Electronics - information, communication, and entertainment • Building and Construction - durability, aesthetics, and high performance • Personal protection - children, athletes, police and firefighters • Innovative packaging - freshness, storage stability, and protection from bacteria • Recyclability and reuse (SPI created the international recycling symbols/numbers to facilitate recycling)
Benefits of PlasticsCase Study: Transportation • During the oil crisis in the 70’s, automakers found that plastics made cars more energy efficient by reducing weight. • Plastics began finding their way into automobile components (bumpers, fenders, doors, etc.) • Plastics were also used for their • Durability • Corrosion Resistance • Toughness • Resiliency • Lightweight
Benefits of PlasticsTransportation cont… • Plastics reduced the weight of the average passenger car built in 1988 by 66 Kgs. • That saves millions of gallons of fuel each year and will save the energy equivalent of 21 million barrels(2428 million litres) of oil over the average lifetime of those cars.
U.S. Plastic Resins Growth – 2004 • Production grew in 2004 to 52 billion Kgs. • An increase of 8.1 percent over 2003. • Sales and captive use rose 6.9 percent, the highest growth rate since 1996, reaching 52 billion Kgs. (Source: American Plastics Council)
Plastics is a complex industry • Processors – (four main processing methods) • Injection Molding • Extrusion • Blow Molding • Thermoforming • Equipment Suppliers • Raw Material Suppliers
Plastics Bags Plastic Packaging Film and Sheet Non-packaging Film and Sheet Plastics Profile Shapes Plastics Pipe & Pipe Fittings Laminated Plate, Sheet and Shape Polystyrene Foam Products Urethane and Other Foam Products Plastic Bottles Plastic Plumbing Fixtures Resilient Floor Covering Plastics Products, Not Classified Elsewhere Range of Products
Today’s Reality • Plastic products have become an integral part of all our lives, and play an irreplaceable role in our day-to-day activities.
Comparison with Other IndustriesUnited States Plastics industry is the nation’s 4th largest manufacturing industry (shipments): • Motor Vehicles and Equipment • Petroleum Refining • Electronic Components and Accessories • Plastics
Scope of the Plastics Industry United States • The U.S. plastics industry employed more than 1.4 million people. • Another 772,000 persons were employed by upstream industries that supplied the plastics industry. • Total of 2.2 million workers – about 2 percent of the U.S. workforce.
Scope of the Plastics Industry United States • Nearly 25,000 plastics industry establishments generated approximately $310 billion in shipments. • Another $83 billion was generated by upstream, supplying industries. • Total annual shipments from plastics activity to $393 billion
Plastics – Global ImportanceImport and Export • Plastic resins and plastic finished products are imported and exported at a significant level across the world, via the oceans and by other means. • Canada, Mexico, other Latin America and China account for dominant percentages of U.S. plastics industry exports and imports.
Growth of Plastics(per capita consumption 2001-2010) 20012010 • North America 101 Kgs 148 Kgs • Latin America 20 Kgs 30 Kgs • Western Europe 94 Kgs 136 Kgs • Eastern Europe 12 Kgs 24 Kgs • Africa/Middle East 8 Kgs 10 Kgs • Japan 88 Kgs 116 Kgs • Southeast Asia 13 Kgs 24Kgs **Less than 2% of a barrel of crude oil is used in the production of plastics. (Source: BASF AG)
Basic Questions (A)Why are rubbish dumps thought to be a bad thing? (B)What does recycling mean?
INTRODUCTION • Plastic is the general common term for a wide range of synthetic or semi synthetic organic solid materials suitable for the manufacture of industrial products. Plastics are typically polymers of high molecular weight, and may contain other substances to improve performance and/or reduce costs. • Plastic is one of the few new chemical materials which pose environmental problem. Polyethylene, polyvinyl chloride, polystyrene, PET are largely used in the manufacture of plastics.
TYPES OF PLASTIC PRODUCTS • PLASTIC BAGS • PLASTIC COATINGS • PLASTIC FURNITURE • PLASTIC SHEETS • PLASTIC FITTINGS • PLASTIC TANKS • PLASTIC TOYS • PLASTIC BUCKETS • PLASTIC SANITARYWARE • PLASTIC STATIONERY
PLASTIC’S ADVERSE EFFECTS ON OURENVIRONMENT Plastics pollute beaches & oceans Garbage has been discarded into the oceans for as long as humans have sailed the seven seas or lived on seashores or near waterways flowing into the sea. Since the 1940s, plastic use has increased dramatically, resulting in a huge quantity of nearly indestructible, lightweight material floating in the oceans and eventually deposited on beaches worldwide.
Plastic bags litter the landscape Once they are used, most plastic bags go into landfill, or rubbish tips. Each year more and more plastic bags are ending up littering the environment. Once they become litter, plastic bags find their way into our waterways, parks, beaches, and streets. And, if they are burnt, they infuse the air with toxic fumes.
Plastic bags kill animals About 100,000 animals such as dolphins, turtles whales, penguins are killed every year due to plastic bags. Many animals ingest plastic bags, mistaking them for food, and therefore die. And worse, the ingested plastic bag remains intact even after the death and decomposition of the animal. Thus, it lies around in the landscape where another victim may ingest it.
Plastic bags arenon-biodegradable And one of the worst environmental effects of plastic bags is that they are non-biodegradable. The decomposition of plastic bags takes about 1000 years.
PLASTIC’S EFFECT ON HUMAN LIFE • Plastic plays the villain right from the stage of its production. The major chemicals that go into the making of plastic are highly toxic and pose serious threat to living beings of all species on earth. • Some of the constituents of plastic such as benzene are known to cause cancer. Plastic resins themselves are flammable and have contributed considerably to several accidents worldwide.
Once plastic is produced, the harm is done once and for all. Plastic defies any kind of attempt at disposal – be it through recycling, burning, or landfilling. • When you recycle a hazard, you create a hazard. • Recycling of plastic is associated with skin and respiratory problems, resulting from exposure to and inhalation of toxic fumes, especially hydrocarbons and residues released during the process.
MEASURES 1.Single-use plastic bags have become such a ubiquitous way of life that it seems as if we simply cannot do without them. However, if we have the will, we can start reducing their use in small ways. 2.A tote bag can make a good substitute for holding the shopping. You can keep the bag with the cashier, and then put your purchases into it instead of the usual plastic bag.
MEASURES • 3.Recycling the plastic bags you already have is another good idea. These can come into use for various purposes, like holding your garbage, instead of purchasing new ones. 4. While governments may be working out ways to lessen the impact of plastic bags on the environment, however, each of us should shoulder some of the responsibility for this problem, which ultimately harms us.
Percentage that can be recycled • About 7% of all household waste is plastic. • Annually, 3 million tonnes of plastic rubbish are produced. • 57% of litter found on beaches is plastic. • In 2001 only 7% of all plastic was recycled.
Why recycle plastic? • Conservation of non-renewable fossil fuels - Plastic production uses 8% of the world's oil production. • Reduced consumption of energy. • Reduced amounts of solid waste going to landfill. • Reduced emissions of carbon-dioxide (CO2), nitrogen-oxide (NO) and sulphur-dioxide (SO2).
How are polymers recycled? • Mechanical recycling of plastics refers to processes which involve the melting, shredding or granulation of waste plastics. • Plastics must be sorted prior to mechanical recycling. • At the moment most sorting for mechanical recycling is done by trained staff who manually sort the plastics into polymer type and/or colour.
More • Following sorting, the plastic is either melted down directly and moulded into a new shape, or melted down after being shredded into flakes and than processed into granules called regranulate.
Source Reduction • Refers to a reduction in the amount of material used in any application • The simplest methods to employ source reduction are • To use fewer products that cause waste • To choose size and types of products where- by waste is minimized • To reduce the material requirements of the product (for manufacturer)
Source Reduction • For example: • The amount of packaging material in 1 litre drink bottle is 40% less than material in 0.5 litre drink bottle (larger size are more efficient in using materials) • Decrease the thickness of materials in application • PE Trash bag (when it was first introduced)- thickness 0.08 mm • LDPE introduced – thickness of trash bag is 0.05 mm • LLDPE (stronger and tougher material) – thickness is 0.025 mm • HDPE – thickness of 0.017 mm is available now.
Recyclingof Plastics • Refers to the reprocessing and refabrication of a material by a consumer or disposal of solid waste. • This type of recycle is called postconsumer recycle (PCR)- different with recycle (generally called regrind) of the scrap from manufacturing process.
Recycling of Plastics • Reprocessing and refabrication of PCR involves several steps; • Collection • Handling/sorting • Reclamation/sorting • End-use fabrication
Collection • Voluntary recycling by the consumer is the most single factor in improving recycling of all materials • However, consumers do not sort their solid waste but rather mix all materials together • For many plastics, the cost of virgin plastics is about the same as the cost involve in recycling- create problem in recycling process (different case with recycling of aluminium cans)
Handling& Sorting • Involves conveying materials from the pickup point (from consumer house) to the reclamation facility. • Sorting of materials is necessary (PET bottle, HDPE waste, aluminium alloy, etc) or in broader material groupings (all metals, all plastics, etc). • For the highest economy benefit, the HDPE and PET and other recyclable plastics must be separated from the plastics that are not to be recycled- thus considerable labour is required to pick up the recyclables by hand.
Handling & Sorting • Some sorting can be done by machine, i.e. based on certain characteristics (light absorption), various plastic resins can be distinguished from the others. • Under certain condition, the mixture of several plastic type can be recycled, called as mixed recycled or comingled recycle. • To assist consumers and sorters, Society for plastic Industry (SPI) introduced recycling symbols.
Reclamation/Cleaning • After sorting, the plastics must be chopped into small flakes or shredded for further processing. • Then the flakes are treated with solvents and washed to remove residual contaminants (original content & paper label). • The flakes are then sent to the fabricators to extrude into pellets.
End Uses- Sorted PCR • The recycled material can be used in the same applications or other applications. • However, PCR plastic cannot be used in medical and food-contacting applications due to danger of contamination and disease. • Thermoplastic- can be reheated and reprocessed many times (with minor changes in resin properties).
Degradation • Means that the plastic can break down into smaller molecules by natural means, biological agent or by sunlight. • In reality, some materials degrade very slowly. • Some applications require that the material do not degrade, i.e. packaging material. • Some applications need degradable properties, i.e. sutures in medical applications.
Waste Tyres • The number of motorcar waste tyres generated annually was estimated to be 8.2 million or approximately 57,391 tonnes. • Landfill- as the easiest way of disposing the waste. • Other industry users collect waste tyres for retreading, rubber reclaim and shredding.
Tyre Waste Examples of use are: Tiles and tile adhesives, mixing with asphalt, sports surfaces, carpet underlay, noise and vibration insulation, playgrounds and matting.
Incineration • Incineration or controlled burning is another option for disposing of large percent of solid waste. • The most common purpose of burning is to generate electricity. Energy content of various solid waste materials and conventional fuels burned to generate electricity.
Incineration Method Incineration can destroy some types of chemicals that other methods can't. It is also quicker than many other methods.
Obstacles of Recycling • Usage of various copolymer blends (i.e. PET) from different manufacturers do not dissolve into one another when heated. Instead, they tend to phase-separate, like oil and water. • Another barrier to recycling is the widespread use of dyes, fillers, and other additives in plastics. The polymer is generally too viscous to economically remove fillers, and would be damaged by many of the processes that could cheaply remove the added dyes. Additives are less widely used in beverage containers and plastic bags, allowing them to be recycled more frequently.