Bengaluru is successfully using plastic waste to lay stronger and smoother roads. And other cities are following suit, as Jayanthi Nararyan discovers.
Though useful in many ways, plastic can be a menace when turned into waste. With this in mind, the ‘Khan Brothers’ from Bengaluru have found a novel use for the heaps of ecologically unsafe plastic that litter the city - they are turning it into eco-friendly, high-performance roads.
In the 1990s, KK Polyflex in Bengaluru churned out hundreds of thousands of plastic bags and other packaging material each month that eventually ended up as garbage. Ahmed Khan, Managing Director, KK Plastic Waste Management and KK Polyflex, says, “When my younger brother Rasool Khan and I were thinking about a solution to reduce the harm caused by our manufactured products, we realised that bitumen and plastic both belong to the petroleum family and both are non-biodegradable. It occurred to us to mix it into bitumen and try it out for road construction.” The result: polymerised bitumen.
Polymerised bitumen is already a rage in Europe and the US. “They make the product with virgin plastic and it is very expensive,” says Ahmed Khan. “Also it is not going to solve the problem of the plastic. Thus, we started on our own. And ultimately we got a breakthrough and without the sanction of the government we tried using the method in a few parts of the city.” Rasool Khan, Director, KK Plastic Waste Management, further explains, “We experimented by putting the mixture unofficially in some small potholes in Jayanagar for two years from 1998 to 2000. To our surprise, the results were positive.”
After the successful smaller experiments, the next step was to ascertain whether the process was safe enough to be used in the city. For this, the Khans approached the University of Bangalore and Central Road Research Institute, New Delhi CRRI). “Highway engineering professors Dr CEG Justo and Dr A Veeraragavan from the University of Bangalore took special interest in the idea and studied it,” shares Ahmed Khan. “To justify the reports, the same technology was tried on a small structure of 500 m,” adds Rasool Khan. “The report was released in 2002 thereby approving the technology. This was an official report by the University of Bangalore.”
Giving his approval to the concept
Dr CEG Justo, Chairman - Technical Committee & Director, Karnataka Road Development Corporation, says, “The use of waste plastic under controlled conditions of processing, mix design and laying as recommended is likely to result in improved performance of the pavement layer.”
The next major task was to get the technology approved for use on city roads. The same year the report was released, the Khans approached then chief minister SM Krishna. After evaluation of the report, Krishna and his office offered full support to the concept.
The next big hurdle was to get plastic for the construction. Though it was in abundance, to actually gather it together was not easy. Thus, the Khans had to find people to supply them with plastic. They contacted pushcart garbage collectors and rag pickers for help and offered them more than what they were making, i.e. about Rs 7-8 per kg. The word spread and people increasingly began to come forward.
They collect the plastic, segregate it into different types and grind it into powder. Different quality grades are mixed in different percentages. This material is then taken to the contractors’ site. There, it is mixed with bitumen and blended. They plan to undertake the blending themselves but right now, owing to lack of funds, it is not possible. A present, the Khans supply the polymerised bitumen to the government, who supplies it to the contractor, who in turn has to buy it as a mandatory process.
This technology can be implemented by two processes: dry and wet. “We are currently using the dry process of making a fine powder of the cleaned plastic and mixing it with bitumen; on site, this is mixed with aggregates and put on the road,” explains Ahmed Khan. “In the wet process, the bitumen and plastic mixture is mixed with only tar. But that requires a lot of investment. And we are planning to do that as our next step.” According to his research, Bengaluru produces 10,000 tonne of plastic waste in a year. The city has 45,000 km of roads that will consume 9,000 tonne of plastic; but right now the Bangalore Municipal Corporation (BMPP) uses only 2,000 tonne of plastic.
The good news is that the BMPP really supports this innovation. “Based on the field study carried out, it has been proved that it enhances the life of pavements,” says BG Raghavendra Prasad, Executive Engineer, BMPP. “We have only one manufacturer who provides low-density polyethylene for bitumen, KK Plastic Waste Management. After the trial project and a proper evaluation for roughness and life of roads, we have laid many such roads in Bengaluru and are making it compulsory for all major upcoming roads projects.”
“Karnataka State PWD has incorporated this material in their Schedule of Specifications for use in bituminous mixes in roads,” reveals Prof Justo.
In addition, Ahmed Khan informs us that the turnover of his company is very poor, hardly about Rs 2 crore. “We are selling it at Rs 30 per kg,” he reveals. “Daily, it is about 7 tonne that comes out to Rs 2 lakh per day. In the rainy season, sales are almost nil. Of course, they are picking up now; last year it was just 1 or 2 tonne per day.”
Road to success
The Khan brothers are also in talks with government officials in Mumbai to implement the concept there. “Per day, the capacity to process is about 25 tonne but right now we are doing 7-8 tonne per day,” they say. “And if you think about Mumbai, it can go up to 100 tonne per day. In Mumbai, the chief minister of Maharashtra himself has shown an interest. Once this is totally implemented, the problem of tackling waste plastic will be solved. If you happen to go to the borders of Mumbai or any other city you will find a mountain of waste.”
They were called by the Brihanmumbai Municipal Corporation for a survey and found that Mumbai generates about 150 tonne of plastic everyday. All this goes into the garbage. In olden days, garbage used to be converted into manure by farmers. They used to dump it in the field and use it as organic manure. Today, because of the presence of plastic, this is not being done. With this concept, the brothers believe the production of organic manure will also improve. “In Mumbai they have banned plastic and so paper is used,” adds Ahmed Khan. “But paper is also a precious resource and if you go on using it recklessly you are depleting the country’s forest wealth.” These eco-friendly roads are highly efficient, with no potholes and absolutely no s and that too with just an extra investment of 1-2 per cent.
This initiative from the Khans has won them many accolades including the Real Heroes Award and the CRISIL Award for excellence. What’s more, the CBSE biology syllabus also discusses their work in the environment section.
Now, the Khans are planning to go for a public issue and mobilise funds to cater to more regions. They are spreading the concept in Hyderabad and Delhi, apart from Mumbai. In Hyderabad they have already bagged a pilot project to lay a 5-km road. “We have got tremendous support from the media,” says Ahmed Khan. “We will not give this up because we see it as a religion.” While the Khans continue to expand their horizons and make this a profitable venture, Bengaluru appears to have found a firm solution to its perennial problem of poor roads.
• The life of a road is increased two times.
• There is extra investment of just 1-2 per cent.
• Potholes and s are greatly reduced.
• Waste plastic is eradicated from the environment and paper is saved too.
• The output of organic manure from garbage is 30-40 per cent; with the removal of plastic, it will be 80 per cent.