The problem of tackling house hold waste is alarming and the infrastructure to handle that by the local bodies on the verge of collapse.
India today collects close to 1,00,000 tonnes of waste per day (the generation is higher and so we see the waste everywhere). And as we urbanise, this problem will only dramatically increase. We all know the reasons for this problem. Increasing urbanisation, coupled with economic development and modern living styles have created this monumental problem in the form of solid waste for urban India. Past frugal habits, almost no use of packaging, no knowledge of plastics, a limited population that was largely rural have given way to a scenario where municipal solid waste generation occurs at each step, without much thought going into the aggregated municipal solid waste (MSW) heaps that are becoming an integral part of our urban (and partially, even rural) landscape.
So what do we do? The first and most obvious and desirable step that has been talked about for some time is: Reduce, Recycle, and Reuse.
But at this stage in our country’s development, this is easier said than done. As we urbanise, some of our past practices are dying and being replaced with new, more convenient practices. I remember, when I was younger, my mother would never go to the market without a bag (typically cloth) of her own. Then, along came plastic bags at each hawkers’ end and out went the earlier re-usable cloth bags. Thus now all the vegetables come home in their own plastic bags. If we also look at most products we buy today, the packing has gone up dramatically.
Similarly, the new urban economy has given a boost to the attitude of convenience and thus changed our age old ways of recycling and reusing. Thus while the Rs 3 as they are called should be the aim of each one of us, we should understand that these generally go against current human behaviour, find limited acceptance and even if successful, will still leave large quantities requiring treatment and safe disposal/utilisation.
MSW collection and management has thus become one of the most difficult and expensive tasks for most municipalities and municipal corporations across the world and in India. Most municipal bodies either spend a substantial part of their budget on this or just see this as a problem with no solution. Even where the waste is being collected, there are limited technical solutions available to handle the waste effectively.
The only real solutions that exist today are listed below:
Landfilling: Most waste collected in the country today is sent to an identified landfill. The landfills are not really scientifically designed and this leads to issues of groundwater contamination (the leachate generated in landfills should be trapped and treated but this is seldom done), air emissions, etc. As the quantum of waste grows, the landfills start choking and become a physical hazard as well. Recently there have been news reports of people dying due to part of the kachra in the landfills collapsing and falling on people (Delhi). In Deonar, Mumbai, parts of the landfill caught fire leading to all of Mumbai suffering smog. These are just a couple of examples but we read and hear such depressing stories each day! Similar stories come from other parts of the world as well like Colombo, Kenya, etc. Thus the landfill can only be an interim solution and that too is becoming an increasingly difficult solution to implement as no one, including villagers, want these landfills in their backyards and for very obvious reasons!
Composting: As per the National Green Tribunal Guidelines, the wet waste (food waste, dung, vegetable and fruit waste, etc) should be composted and the compost so generated should be used as fertilizer. A few sites are doing this but this finally treats less than 10 per cent of the incoming waste. Thus there has to be a solution to handle the balance.
Waste to energy: This seems to be the only real solution that can get rid of the waste in an economical and sustainable manner. But at this point of time, the technology available is complex, has emissions issues and is not available for villages, towns and smaller cities (typical combustion plants need at least 500 tonnes of waste per day). Many of the plants installed earlier have been shut down due to emission issues.
Parameters of an Ideal solution
The ideal solution should thus be a waste to energy technology that does below: