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Solid Waste Management (SWM)

Objectives:

To treat and discard solid wastes in anenvironmentally acceptable manner

To prevent the spread of diseases

To minimize the likelihood of fires

To reduce aesthetic insults arising fromputrefying organics

Basically – to minimize the adverse effectscaused by the indiscriminate disposal ofsolid wastes

If you don’t manage your SW…..

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Impacts due to improper SWM

1. Green house gases – global warming

2. Environmental pollution

3. Human health problems

4. Safety issues

5. Fires within the dumpsite

6. Erosion and stability problems in waste dumpor land fill

7. Odour, vector, rodent and stray animalproblems

8. Aesthetic insults – affects socioeconomics

If you manage your SW properly….

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When assessing SWM possibilities,we need to consider:

Materials flow in society

Reduction in raw materialusage

Reduction in SW quantities

Reuse of materials

Material recovery

Energy recovery

Day to day SWM

Engineered Systems for SWM

The six functional elements of a solidwaste management system

1. Waste generation2. On site handling, storage and

processing3. Collection4. Transfer and transport5. Processing and recovery6. Ultimate disposal

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Waste generationThose activities in which materials are identified as nolonger being of value and are either thrown away orgathered for disposal

On-site handling, storage, and processingThose activities associated with the handling, storage andprocessing of solid wastes at or near the point ofgeneration

CollectionThose activities associated with the gathering of solidwastes and the hauling of wastes after collection to thelocation where the collection vehicle is emptied

Transfer and TransportThose activities associated with the (1) transfer of wastesfrom the smaller collection vehicle to the larger transportequipment and (2) the subsequent transport of wastes,usually over long distance, to the disposal site

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Truck routing

Routing rules (US EPA)

1. Routes should not be fragmented or overlapped. Eachroute should be compact, consisting of streetsegments clustered in the same geographical area

2. Total collection plus haul times should be reasonablyconstant for each route in the community (equalisedworkloads)

3. The collection route should be started as close to thegarage as possible, taking into account heavilytravelled and one-way streets.

4. Heavily travelled streets should not be collected duringrush hours

5. For one way streets, it is best to start the route nearthe upper end of the street, working down it throughthe looping process

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6. For one way streets, best is to make a U-turn

7. For steep hills, collect from both sides while descendingthe hill (saves fuel, safer)

8. Carry out clockwise/ anti-clockwise routes, depending onthe area of collection/ type of drive (left or right hand)

Basically, the best route would be one that saves time,energy of workers and usage of equipment.

Example question

Plan out a routing pattern for the following streets. Assume theNorth-South streets to be one-way and the East-West streets to betwo-way.

Start

End

N

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Processing and RecoveryThose techniques, equipment, and facilities used both toimprove the efficiency of the other functional elements andto recover usable materials, conversion products or energyfrom solid wastes

DisposalThose activities associated with the ultimate disposal ofsolid wastes, including those wastes collected andtransported directly to a landfill site, semisolid sludge fromwastewater treatment plants, incinerator residue, compostor other substances from the various solid-wasteprocessing plants that are of no further use