Kansas company turns trash into alternative energy

NEWTON — Yet another alternative energy technology is chugging away at the former Harvey County landfill.

ICM, a Colwich company known nationally for designing and building ethanol plants, has branched into a related energy technology: biomass gasification.

Instead of turning corn into ethanol, the Harvey County plant converts industrial and municipal trash into gases that can be burned to produce steam and electricity.

The plant isn't fancy. It sits outside and looks a lot like a small oil refinery with towers and a maze of pipes. The office is a mobile-home-like structure.

It can handle 150 tons of waste a day, but it is a demonstration plant, rather than a real working plant, so it's not supplying electricity to anyone. The combustible gases it generates are flared off.

The company says the plant could generate 5 megawatts of electricity per day, enough for 5,500 to 6,200 homes.

It was built about two years ago to let the company perfect its operating capabilities and to show potential developers how productive such a plant can be.

The company said interest has grown, in part because of the imminent expiration of federal tax credits. ICM hopes to sell its first by the end of the year and another three or four in 2012.

Harvey County has long been interested in a waste-to-energy plant. It was the county's interest that led ICM to build its demonstration plant in Newton.

The county is excited about the technology, but Harvey County Administrator John Waltner said the county doesn't generate enough trash to justify borrowing the millions of dollars it would take to build waste processing and power generation, he said. The county generates 70 to 75 tons a day of trash; it needs 120 to 150 tons a day.

But the county continues to work on the project, he said.

"It does cost money," Waltner said, "but it is getting much more cost effective, and it's a lot more environmentally friendly."

How it works

The plant sits on the rural southwest edge of Newton, a mile south of U.S. 50. The Harvey County transfer station and recycling center sits south across 24th Street and a demolition landfill lies to the north.

During a recent tour, the plant's feedstock consisted of a large pile of shredded plastic, garbage, wood and paper, known as Refuse Derived Fuel in the business. Metals and recyclable plastics already had been removed.

It is fed by conveyor belt into a tower where it travels through a series airlocks to be weighed so the machine can be calibrated.

The material then is augered through the 40-foot long insulated steel chamber where it is heated to between 1,200 and 1,500 degrees with very little oxygen, so that it doesn't actually burn up, in a process called gasification.

Gasification produces carbon monoxide, hydrogen and methane, reducing the mass of the feedstock by 80 or 90 percent.

Those gases are burned to produce steam for direct heat or to drive a turbine to produce electricity.

The gasification process can also be tweaked to produce less of the gas and more of a high-carbon ash, called biochar, used to improve soil fertility.

Gasification has been around more or less as is since the late 1970s, said ICM's Bert Bennett, the principal scientist for gasification. ICM has incorporated more precise controls and used improved emissions cleaning systems.

Biomass markets

ICM has been marketing the system for about six months and, so far, has gotten a pretty good response, said Jon Orr, ICM's capital sales manager for gasification.

Having a plant running for a couple years, with two years of results, is key to proving the technology, he said.

This system normally can't compete economically with traditional power sources as coal, nuclear and natural gas.

But the cost structure starts to make more sense when federal tax credits and offsets, such as the cost of burying municipal trash, are included, Orr said.

The federal stimulus bill includes a cash grant, but that expires at the end of 2011. Buyers can also use a federal tax credit that expires at the end of 2012.

ICM sees its natural market in places where land and energy are expensive, such as islands and, to a lesser extent, crowded coastal areas. It is also getting interest from industrial plants that produce waste that could be a feedstock, such as paper-making plants.

Finding enough customers could be difficult given that there are more than 500 companies worldwide offering different waste-to-energy technologies. But Orr said that ICM stands out from most of the pack.

"When you start filtering that list by the number who have demonstration-scale model plants, the list is under 20 in the world," he said.

"At ICM, we have a very strong in-house engineering expertise and long experience building and managing projects from the ethanol side. So, we think that is a unique strength we're offering."

source: kansas