Waste processing technique

Waste processing technique

The processing of wastes helps in achieving the best possible benefit from every functional element of the solid waste management (SWM) system and, therefore, requires proper selection of techniques and equipment for every element. Accordingly, the wastes that are considered suitable for further use need to be paid special attention in terms of processing, in order that we could derive maximum economical value from them.

(i)             Improving efficiency of SWM system: Various processing techniques are available to improve the efficiency of SWM system. For example, before waste papers are reused, they are usually baled to reduce transporting and storage volume requirements. In some cases, wastes are baled to reduce the haul costs at disposal site, where solid wastes are compacted to use the available land effectively. If solid wastes are to be transported hydraulically and pneumatically, some form of shredding is also required. Shredding is also used to improve the efficiency of the disposal site.

Recovering material for reuse: Usually, materials having a market, when present in wastes in sufficient quantity to justify their separation are most amenable to recovery and recycling.  Materials  that can be recovered  from solid wastes include paper, cardboard, plastic, glass,  ferrous  metal, aluminium and  other  residual metals.

(iii) Recovering conversion products and energy:  Combustible   organic materials can be converted to  intermediate  products  and ultimately  to usable  energy.  This can be done either through incineration, pyrolysis, composting or bio-digestion. Initially, the combustible organic matter is separated from the other solid waste components. Once