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The Islamic University of GazaFaculty of Engineering
Civil Engineering Department
Environmental Engineering(ECIV 4324)
Instructor: Dr. Abdelmajid NassarLect. 29-31
Solid Waste Management
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Types of Solid Waste
1. Municipal
2. Industrial
3. Hazardous
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Sources of Solid Waste
1. Municipal Waste1. Residential2. Commercial3. Open areas4. Treatment Plant Sites
2. Hazardous
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3. Moisture content (%) =( )*100
Where a = initial mass of sample as deliveredb= mass of sample after drying
Physical Composition of Solid Waste
1. Individual Components
2. Particle Size
4. Density
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Sampling Procedure
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Chemical Composition
energy content
kJ/kg (dry basis )= kJ/kg (as discarded)
kJ/kg (ash-free dry basis )= kJ/kg (asdiscarded)
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Chemical Composition
energy content
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Chemical Composition
Chemical content
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Chemical Composition
Chemical content
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Example
Component Percent Moisture ContentFood Waste 15 70Paper 45 6Cardboard 10 5Plastic 10 2Garden trimmings 10 60Wood 5 20Tin Cans 5 3
100 79
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Chemical Composition
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Waste management is the collection, transport, processing, recycling or disposal and monitoring of waste materials.
The two conventional principles of waste management were: ‘Dilute and disperse’ or ‘concentrate and contain’.
The main necessity of waste management is to enrich the resources which are being depleted due to rising population and increasing consumption rates.
Management
HEALTH IMPACTS OF SOLID WASTE
Exposure to hazardous waste can affect human health, children being more vulnerable to these pollutants.
Improperly operated incineration plants cause air pollution and improperly managed and designed landfills attract all types of insects and rodents that spread disease.
Direct handling of solid waste results in chronic diseases with the waste workers and the rag pickers being the most vulnerable.
WASTE MINIMISATION
Prevention of waste being created is known as waste
reduction which is an important method of waste
management.
The modern concepts based on the three ‘R’s are: Reduce,
Reuse and Recycle.
Methods of avoidance include reuse of second hand
products, designing products to be refillable or reusable,
repairing broken items instead of buying new etc.
HIERARCHY OF
WASTE MINIMIZATION
WASTE COLLECTION
From individual houses, wastes can be collected in person
with the help of vehicle.
To minimize the time and cost involved in collecting waste
through vehicles, public can be given instruction to dump
their house wastes in one place (nearby their street).
SEGREGATION
Segregation of wastes into degradable and non-degradable wastes is to be done to recover or divert non-degradable wastes (electric items, plastics, tyres etc.) and degradable items (wood, textiles etc.) to its recycling plant and if possible, it can be reused.
It is a tedious process which therefore needs labour. Magnets can also be used to segregate ferrous metals.
This process will help in reducing the amounts of waste going for composting and also earns money (through selling wastes to recycling plant.
RECYCLING
The non-degradable and degradable wastes can be
recycled very economically in the recycling
plants.
Apart from sending wastes to recycling plant, recycling of
some organic waste is possible.
Some of the waste recycling techniques are: Fly ash,
Organic wastes, Slag and scrap, Industrial gases,
Waste waters, Recovery of silver from photographic films.
SHREDDING OR PULVERIZING
This process involves in size reduction of organic wastes
before it goes for composting.
This process reduces the overall volume by 40%.
ADVANTAGES:
It will increase surface area availability for bacterial
activity (decomposition).
Facilitates easy handling of moisture content and aeration.
COMPOSTING
Aerobic composting is one of the cheapest and easiest
methods that are being available for MSW.
Generally, composting can be carried out in three
techniques. They are
i) windrow composting
ii) Aerated static pile method
iii) In vessel method
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