AAES to distribute Waste to Energy gasifiers

By Erin Voegele
Web exclusive posted August 29, 2008 at 9:33 a.m. CST

American Alternative Energy Systems Corp. announced Aug. 25 that it has reached an agreement with Toronto-based Waste to Energy Gasification Systems Inc. to obtain the American distribution rights to the company's patented Waste to Energy downdraft gasifier technology. They system, developed in the mid 1990s in the United Kingdom, was originally designed to produce energy from sewage sludge and other toxic organic wastes. Recently, the technology was upgraded to process virtually any type of municipal solid waste stream, including commercial and industrial wastes.

AAES is focused on reducing greenhouse gas emissions and creating a more sustainable environment through the use of wind, solar, and biomass. According to a company statement, AAES will produce anaerobic digesters that will turn manure and other bio-waste into electricity and heat.

The Waste to Energy system is modular, with the biggest module capable of processing approximately one dry ton of waste per hour. The technology is ideal for processing small local waste streams and sewage sludge that have been ‘digested' to remove volatile organic materials. The Waste to Energy gasifier processes these materials into efficient engineered fuels for local power and steam production.

According to Waste to Energy's Web site, the technology uses a pyrolysis technique to convert biomass materials into energy. Dried solids are mixed with air and heated to a high temperature. The amount of air is strictly controlled, causing the solids to give off gases without combustion. The gases then pass through a unique vortex core at a temperature of approximately 1,200 degrees Celsius (2,192 Fahrenheit) and are cleaned of tars and oils. The gas passes directly into a power gas generator, which produces electricity and hot water. However, even though the core temperature is 1,200 degrees Celsius (2192 Fahrenheit), the outer surface of the gasifier remains cool to the touch. The process is self-contained and does not emit gases into the atmosphere.

"The Waste to Energy technology represents a significant breakthrough in the way we will destroy troublesome waste streams while producing local renewable energy," said Dr. Wayne Maddever, chief executive officer of Waste to Energy (Canada) Ltd. "The focus of the waste to energy sector has evolved over the past few years away from incineration with waste heat recovery towards very efficient, low-emission gasification systems that produce a combustible gas, rather than simply burning the material to generate heat to produce steam."

Maddever said the relatively low British thermal unit syngas works extremely well with the new breed of specialized combined heat and power (CHP) systems and maximizes the overall usage of the stored energy in the waste, while minimizing the huge volumes of nitrous oxides produced by incineration of waste streams with free-flowing air.

Maddever said there could be a huge market for the small, modular systems, which can be multiplexed to service all but the largest waste processing facilities. "We at Waste to Energy Canada see an opportunity to provide a clean, inexpensive way of converting the most difficult and noxious waste streams into the maximum possible amount of energy, with no impact on the environment except a positive one," he said.