Solid waste no more

January 19, 2014

Solid waste no more

Lahore, with a population of well above 9 million, generates 5,000 tonnes of solid waste every day. The stated collection efficiency has been around 62 percent, which means that the remaining 38 percent would remain uncollected. In the absence of proper scientific disposal facility, it has remained a major challenge for waste managers how to get rid of the stuff. For ages, this waste was dumped in empty plots, playgrounds, on the roadsides and even left unattended in residential areas. A popular way to dispose off solid waste was to burn it on the spot. This would lead to environmental pollution, causing inconvenience to the residents of the area where it was burnt. On occasions, it would also result in fire, spreading beyond limits. All this time, the people of Lahore had no idea this solid waste was not as useless a commodity as they had thought it to be. There were buyers but the way they used this waste to produce recycled products was never approved of. There were even reports of medical waste such as used syringes, urine bags and other plastic material being recycled and used as raw material to produce shopping bags, drinking water bottles and plastic toys for children. All these products posed serious health risks to the human beings who came into contact with them. Settlements of scavengers developed next to the dumping grounds where they would spend all day to collect different commodities. These commodities were sold by them to different buyers (raddi walas and kabaria) who would readily buy plastic stuff and bottles, glass pieces and bottles, pieces of rubber tyres, metal products and so on. Recently, there has been a bad news for this alliance of scavengers and waste buyers as new players have entered the market. In an amazing development, the demand for this stuff has risen so much that its suppliers fear its shortage in times to follow.

The buyers are none other than industries that are looking at newer sources of energy to run their units. With electricity shortage increasing by the day and fossil fuel becoming more and more expensive, it has become increasingly difficult for the industry to keep their business going. Nusrat Gill, an environmental consultant and senior manager planning at Lahore Waste Management Company (LWMC), says solid waste is being sold to industrial buyers in large quantities. For instance, DG Khan Cement company has set up a facility next to the landfill site in Lakhoder area at the cost of Rs2 billion. Here, the waste is treated and Residue Derived Fuel (RDF) is separated for consumption in the factory as fuel. Explaining the concept, he says RDF is a fuel produced by shredding and dehydrating solid waste with the help of technology developed for the purpose. It consists largely of combustible components of municipal waste such as plastic, paper, wrappers and other biodegradable waste. The non-combustible material such as glass and metals are removed mechanically. In the developed world, RDF processing plants are routinely set up close to the disposal sites of municipal waste. According to Gill, there was skepticism from some quarters when the LWMC signed an MoU with DG Khan Cement. He calls it a great development that the plan has materialized. "Today, the party is buying waste and using the material derived from it to run its units."

As per the contract, the cement factory buys 1,000 tonnes of solid waste per day from the LWMC at the rate of Rs50 per tonne. The RDF it thus produces is sent to its industrial units in the form of bales where it is burnt in lieu of fossil fuel. The cement industry uses RDF in place of coal. It is estimated that around 2.5 tonnes of RDF is required to produce a similar amount of energy produced by burning one tonne of coal. The best part of the story is that RDF is far more environment friendly than coal and this usage serves two processes-it produces energy and disposes off waste in best possible way, says Nusrat. Asad Ahmed, a spokesperson at the company, says the sale of municipal waste to industry as a source of energy is a relatively new concept. Otherwise, he says, waste is being provided free of cost to Lahore Compost Company for processing. The company gets free delivery of 500 to 800 tonnes of waste every day. The organic material is used by the company to produce compost which is sold as fertiliser. It also produces RDF for supply in the market. There are other options as well which include capturing of gas produced by the decomposition of organic waste at Rs7 billion landfill facility set up at Lakhoder. "Currently, this gas is lost in the atmosphere and goes to waste," he says. Muhammad Mubashir, an energy sector professional, says RDF is mixed with quantities of coal to acquire required temperatures at industrial units. It saves cost as well as cuts on import of coal for the purpose. A large number of industries are mulling to start RDF which means there will be a huge demand for this product in times to come. This is one reason why landfill sites are being set up in other parts of the country as well. "In the long run, environment will benefit a lot as people will not have dump their waste in rivers and canals," says Mubashir. Wasif Azhar, Senior Manager Operations and In-charge Waste-To-Energy Section, LWMC, says that a large number of foreign companies are visiting Pakistan. They plan to tap the potential that lies in this sector. There are suggestions that units producing electricity from waste should be installed at industrial sites so that the heat produced during the process is also tapped and sold to industries which need heat/steam as an industrial input. Azhar says the heat thus produced is used in the West indoors through piped supplies but this is not applicable in a country like Pakistan where the climate is already warm. The efficiency of producing electricity from solid waste alone is only 20 to 25 percent but it can be raised to 60 percent if heat is also utilised, he adds.

Solid waste no more