I'M surprised that incineration technology still hasn't taken off in Pakistan, considering the waste disposal issues and, most importantly, energy crises our country faces -- only half of Karachi's 8,000 tons of garbage per day is sent to the already-scarce landfills.

Incineration involves burning garbage to heat the steam needed for producing heat and electricity -- traditionally, more polluting fossil fuels such as petroleum or coal are used instead. With incineration, we not only put our garbage to good use, but it also cuts down the landfill space needed for garbage disposal extensively.

Modern incineration facilities separate recyclable materials and hazardous waste before sending the garbage to the incinerators, and properly-equipped modern incineration facilities give off extremely low emissions, and toxic flue gases emissions are also minimised using technologies such as bag-house filters.

The only by-product is ash, most of which (bottom ash) can be reused as construction material or for pavement, while the remnant fly ash, which is toxic, has to be disposed in a sealed landfill. What's more, incinerators can be erected anywhere, anytime, and have a fairly simple operating formula.

Apart from incineration, that had its inception back in the 70s, waste-to-energy technology has prospered tremendously by now. Recovering methane from landfills for use as fuel, known as landfill gas, is a fairly well-known method in developed countries now.

Companies have recently come up with processes that can recover biogas, a low-emission environmentally friendly fuel, from sources such as sewage and industrial waste. These sources are capable of producing enough electricity to power a large town, and incineration produces even more.

While the cost of these technologies is not the lowest, it is more affordable than petroleum in the long run. Besides, these prices are expected to go down as the world is now in dire need of environmentally friendly renewable energy. Furthermore, many of these technologies were designed with developing countries in mind, like Pakistan.

I hope that Pakistani energy suppliers would look into the huge potential of waste-to-energy technologies as a long-term answer to its energy crises, waste disposal and environmental problems.

MOHAMMAD ALI

Canada