1. INTRODUCTION
Plastic, with its exclusive qualities is now a serious worldwide
environmental and health concern, essentially due to its non-
biodegradable nature. More than 50% of the plastic waste
generated in the country is recycled and used in the
manufacture of various plastic products.
Dioxin is a highly carcinogenic and toxic by-product of the
manufacturing process of plastics. Burning of plastics,
especially PVC, releases this dioxin and also furan into the
atmosphere.
Plastics are so versatile in use that their impact on the
environment is extremely wide ranging. Careless disposal of
plastic bags chokes drains, blocks the porosity of the soil and
causes problems for groundwater recharge. Plastic disturbs the
soil microbial activity. Plastic bags can also contaminate
foodstuffs due to leaching of toxic dyes and transfer of
pathogens. In fact, a major portion of the plastic bags i.e.
approximately 60-80% of the plastic waste generated in India
is collected and segregated for recycling. 20 – 40% remains
strewn on the ground, littered around in open drains.
Designing eco-friendly, biodegradable plastics are the need of
the hour. Though partially biodegradable plastics have been
developed and used, completely biodegradable plastics have
only recently been developed.
The various sources of generation of plastics wastes include:
Household such as (Carry bags, Pet bottles, Containers, Trash
bags), Health and Medicare(Disposable syringes, Glucose
bottles, Blood and urine bags, Intravenous tubes, Catheters,
Surgical gloves), Hotel and Catering (Packaging items,
Mineral water bottles, Plastic plates, cups, spoons) Air/Rail
Travel(Mineral water bottles, Plastic plates, cups, spoons,
Plastic bags)
Characterization studies indicate that MSW contains large
organic fraction (30-40%), ash and fine earth (30-40%), paper
(3-6%) along with plastic glass and metal (each less than 1%),
calorific value of refuse ranges between 800-1000 kcal/kg and
C/N ratio ranges between 20-30%. The collection bin and
implements used in various cities are not properly designed. It
has been observed that community bins have not been
installed at proper location. This has resulted in poor
collection efficiency. Lack of public awareness has made the
situation worse. Various types of vehicles are used for
transportation of waste to the disposal site. However, these
vehicles are not designed as per requirement. In many urban
centers, proper garages are not provided for the vehicles for
protection from heat and rain. Preventive maintenance system
is not adopted and as a result the life of the vehicle is reduced.
Many of the vehicles used for transportation of waste have
outlived their normal life.
Waste is disposed off in low-lying areas without taking any
precautions and without any operational control. Solid waste
workers handle the waste without any protective equipment
and are prone to infection.The waste characteristics are expected to change due to
urbanization, increased commercialization and standard of
living. The present trend indicates that the paper and plastics
content will increase while the organic content will decrease.
The ash and earth content is also expected to decrease mainly
due to an increase in the paved surface. Although
content is expected to decrease, the material will still be
amenable to biodegradation and the calorific value will
continue to be unsuitable for incineration.
In keeping with the present practices and estimates of waste
generation, around 90% of the generated wastes are land filled
requiring around 1200 hectare of land every year with an
average depth of 3 m. Due to rapid urbanization
land use regulation and completing demands for available
land, it is desirable that adequate land be earmarked at the
planning stage itself for solid waste disposal. The larger
quantities of solid waste and higher degree of urbanization
will necessitate better management involving a higher level of
expenditure on manpower and equipment.
Plastic in Municipal Solid Waste
• Toxic Nature
• Stagnation of waste water due to waste plastic causing
hygiene problems
• When mixed with solid waste, it reduces the rat
composting of the organic solid waste.
• When waste plastic is mixed with earth, the water flow is
affected. .
• Misuse and its dumping in the dustbins and drains.
Management of Waste Plastic
• Reduce (A ban on thinnest Polybags)
• Reuse (Bisleri & cold drinks bottles)
• Recycle (60-70 %)
• Plastics as a Greenhouse Gas Emission Saver . Use of
Plastic
• Plastic in Packaging
• Plastics in Automobiles
• Plastics in Insulation materials in construction industry
• Plastics in Piping
Plastics in Packaging
• Non toxic characteristics, inertness & chemical resistance
• Excellent barrier properties & water-proof characteristics
• Non-breakability and light in weight
• Transparency as well as opacity
• Resistance to bacterial and other microbial growth
• Pilfer proof characteristics etc
Benefits of plastic bags / carry bags
• Add convenience to day-to-day life
• Increases shelf life of contents / light weight• Essential for packaging of bread
bakery products
• Essential for packaging of hygroscopic edible products
like sugar, salt, jaggery
2. USE OF PLASTIC WASTE
• India Plastic Recycling Industry give Employment and
business Opportunities to many families. Its Turnover is
Rs.15, 000 Crores, Volume recycled is 2.6
MillionTonnes, No. of units are 10
employment about 3.5 Million
Million.
• Carbon Recycling: Fuel from Plastic Waste:
Waste yielding 900 litres of Diesel conforming to highest
quality EN 590 diesel. Maharastra signs MOU to produce
fuel from plastic.
• Unconventional Recycling:
better roads.
• Energy Recovery: Co-Processing in cement kiln: Partial
substitution of fossil fuel. Process has been certified by
approved pollution control authority in India. Its benefit is
all types of plastic waste fed wit
adequate cleaning. ICPE-ACC Plant2.1. Properties that makes Plastic Waste suitable for roads
construction
• Better Coating Ability to aggregates
• Improved bonding between binder & aggregates
• Higher Marshall stability
• Higher resistance to fatigue and permanent deformation
characteristics.
• Less susceptibility to water damage
54
Essential for packaging of bread, confectionery items,
Essential for packaging of hygroscopic edible products
AS A RESOURCE
India Plastic Recycling Industry give Employment and
to many families. Its Turnover is
Volume recycled is 2.6
No. of units are 10, 000, Total
ment about 3.5 Million, Rag Pickers about 1.5
Carbon Recycling: Fuel from Plastic Waste: 1 MT
Waste yielding 900 litres of Diesel conforming to highest
quality EN 590 diesel. Maharastra signs MOU to produce
cling: Use of Plastic Waste for
Processing in cement kiln: Partial
substitution of fossil fuel. Process has been certified by
approved pollution control authority in India. Its benefit is
all types of plastic waste fed without segregation / without
ACC Plant established in
M.P. in India for the first time.
Table 1. Plastic Waste for Better Roads
2.1. • Conservation of bitumen and aggregates
• Long service life
• More durability
• Improved performance
• Can be used in all climatic conditions
• No difference in binder content
• Reduced stripping due to plastic coating
• Disposal of plastic made easy
• Value addition to plastic leading to development of
management of garbage culture.
3. THREE DIFFERENT PROCESS USED IN ROAD
LAYING USING WASTE PLASTIC ARE
3.1 Waste Plastic–Aggregate-Bitumen Mix Road
Construction
The process of road laying using waste plastics is designed for
construction of bituminous roads at various places in India. A
brief description is given below.
Disposed Plastics waste (films, cups and thermocol) are
sorted and cleaned
Waste Plastics to the required size(passing 6.75 mm and
retaining 2.36 mm) are shredded
Heat the aggregate to around (160-170° C)
Quantitative Addition of shredded polymer waste with proper
mixing technique to get a uniform coating at the surface(30-
40 sec only)
Quantitative addition of hot bitumen whose temperature is
maintained between 155-163 ° C
Mix the waste plastic-Aggregate bitumen to get a uniform
mix(composite)
Bitumen-Polymer waste-aggregate mix(composite) is taken
out around 130-140 ° C and used for road laying
Road laying is done between 110-130 ° C to get better result
using 8 ton roller.
3.2. MINI HOT MIX PLANT PROCESS-RURAL ROADS
AND HIGHWAYS
Following steps are followed in this Process :-
• Collected waste plastic is segregated and shredded into
small piece with size passing & retaining at 4.75 mm and
2.36 respectively.
• Solid aggregate(granite, ceramic) with proper proportion
of metals having different size and dust, heated up to
170ºC in mini hot mix plant is transferred to adjacent
puddling chamber. Simultaneously bitumen 60/70 or
80/100 is heated to only up to 160ºC.Periodical
temperature monitoring should be done during heating of
both.• Shredded plastic(5%-20% by wt of bitumen) is sprayed
on hot and continuously stirred aggregate in puddling
chamber to get uniform coating at surface of aggregate.
This process takes 30-45 seconds.
• Bitumen(160ºC) is added to it and mix uniformly at
155ºC-163ºC (as per IRC specification).after mixing this
mix which is known as waste plastics-aggregate-
bitumen is withdrawn at around 140ºC.
• The polymer tar road is laid by spreading uniformly the
waste plastics aggregate bitumen mix and rolled using 8
roller, as per the IRC specification.
• Quantity of addition of plastics to be used and proper
temperature monitoring of mix during laying of road in
addition to heating aggregate and bitumen, are of utmost
important and should be done properly and accurately.
3.3. ROAD LAYING USING CENTRAL MIXING
PLANT(CMP)
This process is used for laying long roads with less time
schedule. Following are the steps for polymer tar road laying:-
• In this process, waste plastic is used according to the
proportion of bitumen in accordance with the moving
time of conveyer belt. For example for one tone of
bitumen 100 kg of plastic should be moved with
3.33kg/minutes on conveyer belt. Till date, this addition
on conveyer belt is done manually.
• This plastics then move to hot drum where it gets melt
and coated over pre-heated aggregate of 170ºC.
• The bitumen is added subsequently and the aggregate
polymer bitumen mix is released and collected in tipper,
having proper insulation, uniform coating and
temperature of 140ºC.
• This mix is transported road laying site.
• Before spreading this mix, the surface has given tack
coating using emulsion or 60/70 bitumen, as per IRC(IV)
revision specification.
• Finally mix is spread over it using paver machine and
then compacted with 8 tons roller.
• Convenient for carrying fish, meat, poultry and other wet
food products – no other better alternative.
4. MISCONCEPTIONS ARE :
• Health & safety
• Toxicity
• Biodegradability
• Disposal & waste management
4.1. Issue: Health & Safety:
• Use of polyethylene in contact with food stuffs,
pharmaceuticals and drinking water is approved by
regulatory authorities across the world including that in
India(BIS Specification IS 10146:1982 – Reaffirmed on
Feb-2003)• Polythene is also approved safe material for use …
• as implants within human body
• In medical applications like IV bottles
• Packaging of tablets
• Plastic bags are generally made from polyethylene / PP
safe product
4.2. Issue: Toxicity
Myth :
• Plastics are termed as “toxic and Injurious to health
Reality:
• Plastics are inert materials and do not pose any danger of
toxicity
• Additives used in plastics are approved as per BIS / FDA
standards
• Emissions at fire situation have similar or lesser
implications in comparison to situation involving natural
organic materials like wood & cotton
• Emissions during burning of paper and polyethylene are
similar
4.3. Issue: Non-Biodegradability
• Termed as “the major reason of waste management
problem”
• Plastics are useful for its long life characteristics
• Tin, Aluminum, Glass also are not biodegradable
• Biodegradable plastics are needed for specific
applications like nursery bags, mulch/agricultural film
one – time use cutlery / cups etc. to be carried in ships /
remote areas
• New development of biodegradable plastics m
lamination with jute / paper
4.4. Issue: Disposal
Myth :
• Plastics are blamed as “the major cause of solid Waste
problem”
Reality:
• According to Indian studies plastics form about 5% of
total MSW
• While all solid / thick plastics waste are systema
picked up by the waste collectors for recycling
of thin plastic carry bags, single-use plastic waste and
multi-layer packets have created solid waste problem
• Alternatives to Plastic are
• Jute
• Textile
• Paper
• Degradable PlasticsREFERENCES
[1] Manual on Municipal Solid Waste Management
Ministry of Urban Development
2000
[2] Environmental Engineering By A Kamala
Rao, tata Mc Graw – Hill Publisihing Company
Limited
[3] Elements of Environmental Science and Engineering
By P. Meenakshi, Prentice Hall of India private
Limited.
[4] Environmental Science By Dr. Jyoti Sinha
[5] Handbook of Solid Waste Management By Frank
Kreith.
[6] Foundation of Environmental Studies By Prof. Dr.
Devendra S. Bhargava
[7] Air PollutionVolume IV Engineering Control of Air
pollution By Arthur C. Stern.
[8] From Central Road Research Institute New Delhi.
[9] LCA Report of IITD.
[10] ULS Report (USA) on LCA.
