Proven Technology

 

Thermochemical Conversion Technologies

Thermochemical conversion using pyrolysis and gasification is a process that uses high temperatures with very low or no oxygen to break down large organic molecules into producer gas. This gas is then either combusted directly to produce heat for steam/electricity, or used to synthesize fuels or chemicals.

 

Thermochemical conversion is capable of treating nearly the entire organic fraction of municipal solid waste. These technologies can, in general, treat a wider array of material than biochemical conversion technologies, including high energy-content plastics that have no market value.

 

Pyrolysis is a high-temperature process that uses little or no oxygen to break down organic materials into a range of pyrolytic oils and gases. Temperatures for pyrolysis processes typically range from 750°F to 1,500°F. Gasification is also a high-temperature process —typically above 1,300°F— along with carefully controlled secondary introduction of air, oxygen, steam, or hydrogen to convert feedstock into a synthetic gas or fuel gas. Of the two methods, gasification is more technologically complex, but offers the capability of producing a broader array of products such as electricity, fuels (methane, hydrogen, ethanol, synthetic diesel), and chemical products.

 

Thermochemical conversion differs from incineration in two key respects:

• The desired product gases in thermochemical conversion are low-molecular weight hydrocarbons, carbon monoxide, and/or hydrogen. Incineration involves complete combustion to carbon dioxide and water.
• The volume of gas produced by thermochemical conversion per ton of material processed is much less than incineration (typically 10%). The lower volume makes gas cleanup/air pollution control far easier and less costly than that required for incineration.

Pyrolysis and gasification applications for municipal solid waste (MSW) have expanded considerably in the past five years, especially in Japan, which has limited domestic resources and limited landfill space. There are more than 50 commercial facilities currently operating in Japan. These facilities are processing approximately 2 million tons per year (equivalent to about 8 percent of current total waste disposed in California).

Environmental Impacts

Emissions from thermochemical-conversion-to-energy processes can include air pollutants such as oxides of nitrogen and sulfur (NOx and SOx), hydrocarbons, carbon monoxide (CO), particulate matter (PM), volatile heavy metals, greenhouse gas emissions such as CO2, and dioxins/furans. Our patented process will contain the resulting emisions which will not be released into the atmosphere or water.

 

In addition, fugitive gas and dust emissions will be controlled with our operational practices which will be maintained at each facility (for example, enclosed receiving buildings will have exhaust air treatment to minimize VOC and dust emissions from unloading and feedstock storage). Our Thermo Conversion process will employ air pollution control at the reactor outlet as well as the exhaust gas outlet.