CITY PLANS TO TALK TRASH WITH 4 FIRMS LANDFILL ALTERNATIVES SOUGHT.

Byline: Kerry Cavanaugh Staff Writer

As part of an effort to wean itself from the need for landfills, the city will study how to turn trash into energy or compost under technologies pitched by some 140 companies worldwide.

The Board of Public Works has about $400,000 to hire a consultant who will sift through the options and find reliable, safe and affordable technologies, said Alex Helou, solid resources support services division manager. The Bureau of Sanitation has narrowed the field to four large engineering firms and will recommend one to the board in the coming weeks.

``We have to really cut through the sales pitches and look at the real scientific data,'' Helou said.

The landfill alternative investigation is part of the city's plan to stop sending residential trash to Sunshine Canyon Landfill in 2006. Sanitation officials are also seeking contracts to send trash to landfills outside the city limits.

Conversion technology - the process of changing trash into consumer products - is used in Europe, Australia and Canada but hasn't caught on in the United States, said Fernando Burton, who heads the California Integrated Waste Management Board's analysis of conversion processes.

``There isn't a lot known about the commercial scale use of these things, so it's hard to answer some of the questions,'' Burton said.

Cost is also an issue, as conversion plants can cost $40 million or more.

There are essentially two types of conversion technologies the city will consider, using heat or bacteria to break down trash.

Heat-based technologies include gasification and pyrolysis, which both put trash in a sealed container and use heat and pressure to convert materials into methane, hydrogen or carbon dioxide gases.

The leftover material, which is much reduced in size, is dumped in a municipal or hazardous waste landfill, depending on makeup of the materials.

Pyrolysis uses an oxygen-free container and may produce fewer air pollutants, Burton said. A pyrolysis plant that would dispose of fireworks and medical waste is planned for Riverside County.

The other major conversion technology uses biological methods, such as anaerobic digesters. The equipment can usually only handle materials that break down biologically, such as food, green waste and paper products.

The materials are put in an airtight container, where bacteria munch through the products and generate methane and carbon dioxide. After the gas is collected, the pulpy leftovers can be used in composting.

The consultant hired by the city will have to analyze the types of trash generated by residents and businesses, the potential operating costs of plants and any air-emissions concerns, Helou said.

Even as the city investigates this cutting-edge technology, some observers say conversion technology will not solve the city's trash disposal predicaments.

Last year, Mayor James Hahn appointed a task force to explore alternatives to landfills, and the group pressed the city to look at conversion technologies.

But task force chairman, University of California at Los Angeles Public Health Professor Rick Greenwood, said the group ultimately felt conversion technology could handle only a small amount of the city's trash.

``There's some very clever things going on,'' Greenwood said of the conversion methods presented to the task force. ``When you start talking to people who have them, it's in the design stage, it's in the theoretical stage or it's a pilot program.''

Kerry Cavanaugh, [phone]

kerry.cavanaugh(at)dailynews.com