Mar 21, 2003
Developments in plastics recycling.
In India success in recycling of consumer level plastics is going to be governed by the profitabilty of the recycling idea. There are millions of urban Indians who scour our cities for an income from waste. They play an insufficiently celebrated role in waste management. A few months ago the Mumbai Corporation moved to formally recognise their role in waste management. They will be propagandists for waste segregation. That’s first step in both recognising a problem and those that may constitute a solution.
That plastics --mostly as carry bags-- form the most formidable threat to public spaces is being realised rapidly. City administrations also know the futility of banning their use. One promising solution tp the problem is from Prof. R Vasudevan of Thiagarajar College of Engineering, Madurai. He thought up the idea of shredding plastic waste, mixing it with bitumen and using the polymerised mix in road construction. Chennai Corporation reacted with commendable speed. In Nov, 2002, it laid out a short stretch of road to test the idea. It has now declared itself satisfied with the trial. Chennai generates close to 150 tonnes of plastic waste everyday. If the Corporation buys, as it says it will, the plastic-waste-for-road-laying idea could be a win-win situation: better roads, money for the poor and cleaner environment.
On Mar 9, 2003, UNI reported an exciting development from Nagpur. Liquid fuel by releasing hydrocarbons locked in plastics. After all, from oil they came and to oil they could return. “I just break up and make up a few bonds which ultimately results in the conversion of plastic waste into fuel,” said Prof. Alka Umesh Zadgaonkar of Raisoni College of Engineering, Nagpur. UNI added thus: “Demonstrating her invention at Mavlankar Auditorium here over the week end, Zadgaonkar put one kg of plastic waste in a reactor which was converted into mixed fuel within three and a half hours. In the second stage, the mixed fuel was subjected to the process of fractional distillation, which yielded 800 ml of petrol.” The report further says that the political establishment that witnessed the demonstration was impressed. [ Read update: Feb,2006 ]
Approaching the problem from another direction, Sriram Institute of Industrial Research, New Delhi has sought to create solid fuel from plastic waste. This report quotes Dr R K Raina as saying : ‘What we have done is to explore ways to improve upon the properties of plastic as fuel. We prepared different types of fuels by simply adding wastes like sawdust, waste paper, leaf, and coal dust. All the blended fuels showed marked improvements in ease of burning. This is because wastes help to increase the porosity of plastic that traps oxygen, helping it to burn’. The end product is a readily saleable fuel brick. The Institute says the process is so simple that villagers can recycle plastics by mixing them with bio wastes at 110 deg. C. and earn sizeable incomes.
It is estimated that India generates 5600 tonnes of plastic waste daily. That is bound to grow. It is reassuring that inventive minds all over India are working to turn a huge problem into an advantage— hopefully one that doesn’t compromise the environment.