Los Angeles County Public Works Department Exploring State-of-the-Art ‘Waste-to-Energy’ Technology
by Coby Skye and VerdeXchange News
The ability to convert waste to energy mitigates two environmental issues with one process: first, reducing the amount of waste that heads to landfills; second, providing a renewable, carbon-free form of energy. As a result, waste-to-energy is a hot-button technology, essential in the carbon mitigation efforts of public agencies such as the Los Angeles County Department of Public Works (DPW). Having just completed Phase II of a report evaluating waste-to-energy conversion technology, DPW associate civil engineer Coby Skye shared with VerdeXchange News several applications of this promising emerging technology and its potential to transform the sustainable practices of waste management operators.
VerdeX: L.A. County just released Phase II of a report called “The Los Angeles County Conversion Technology Evaluation Report.” What was the report’s ambition, and what are its important findings?
Skye: For the last several years, we’ve been evaluating what we term “conversion technologies.” These are thermal, chemical, and biological processes that take municipal solid waste—that’s the trash that’s left over after we’ve pulled all the recyclables out of it—and convert that very heterogeneous material into energy, fuel, and products, without burning the trash. The county has been working to identify those companies and those technologies that we feel are viable and capable of developing successfully in Southern California. VerdeX: Elaborate on the mix of conversion technologies the county is considering. What’s already in market? What’s about to be in market? What’s needed in market?
Skye: For example, in the Phase II report, we identified four companies that we’ve recommended as viable and capable of handling solid waste and converting it into renewable resources, specifically a biological technology, anaerobic digestion, and three thermal technologies. Anaerobic digestion is just one example of these unique processes. Essentially, this particular company takes trash and puts it into a water vat. The water allows the technology to separate out the different components in the waste stream, targeting the organic fraction of the waste—the biogenic fraction that is easily compostable or biodegradable. It feeds that part of the waste stream into an upflow anaerobic digestion process, which breaks down the organic material into methane—basically natural gas—which you can use for producing electricity, chemicals, or other products.
