Monday, November 24, 2008

Peak Oil: Meet Pyrolysis Oil

Pyrolysis oils are created when high carbon materials--such as biomass or old tires--are heated in the absence of oxygen. The materials in pyrolysis oils can then be refined and stabilised to use as replacements for petroleum oils. For tires:
Pyrolysis degrades tyres using externally applied heat. The chamber containing the tyres is oxygen free, so that the tyres decompose, giving off gas, then oil, leaving a mix of char and steel.

This is then separated, further refined and converted into constituent parts – steel, carbon black, oil and gas. As the process takes place in a sealed chamber, there are no noxious emissions. _Plastics&Rubber
For biomass, the end product of the pyrolysis reaction is a bit different, but highly serviceable.
Biomass pyrolysis oil, commonly referred to as bio-oil, is made from second-generation feedstocks such as agricultural and forestry residuals. The DOE defined the act of stabilizing bio-oil to include removing char, lowering the oxygen content, and reducing the acidity of pyrolysis oil because it’s naturally corrosive, unstable and difficult to transport. When the stabilization of bio-oil is successful, it could be used at petroleum refineries as a feedstock that is greenhouse-gas-neutral, renewable and domestically produced.

...Five funding recipients have been selected to date, including Illinois-based UOP LLC, a Honeywell International Inc. subsidiary that has partnered with Ensyn Corp., the National Renewable Energy Laboratory, the Pacific Northwest National Laboratory, Pall Corp., and the USDA Agricultural Research Service’s Crop Conversion Science and Engineering Research Unit. The group’s project is centered on the development of a commercialized next-generation technology to refine bio-oil for use in power generation, as a heating fuel and eventually as a transportation fuel.

...North Carolina-based research institute RTI International will also receive funding for its proposal that primarily aims to develop highly active and stable catalysts for the stabilization of bio-oil, potentially resulting in a condensed bio-oil intermediate that has physical and chemical properties adequate for use as liquid transportation fuels in existing petroleum refineries or in standalone, centralized upgrading facilities. _Biomass
Another significant pyrolysis project involves a collaboration between European energy giant Siemens and the USDA's Agricultural Research Service (ARS).
The company will install a distributed control system based on Siemens’ Simatic PCS 7 Box technology on the ERRC’s bench-scale fluidized bed pyrolysis system. “We think distributed control will help accelerate second-generation biofuels and biochemicals development by improving the repeatability, consistency and efficiency of our research processes,” said USDA ARS Research Leader Kevin Hicks.

Siemens’ technology will help control the reaction process by controlling variables inside the reactor. This will allow researchers to have a repeatable environment where heat, pressure and other variables are automatically controlled. Controlling these variables will make it easier to compare the bio-oil produced from various biomass materials. “What we are really concentrating on is taking low-density biomass, having a consistent reaction and then being able to put it into this bio-oil form we can use,” Chmielewski said. One goal of the research is to identify the best feedstocks suited for specific end products.
As noted here previously, pyrolysis involves lower temperatures than gasification, and is done in an oxygen-free atmosphere. The products of pyrolysis are more complex than the products of gasification. Until now it has been difficult to achieve consistent quality of product, and effective chemical stability of product for storage and shipping purposes. As you can see from the articles above, a lot of money and quality effort is being expended to assure that pyrolysis products achieve a much bigger slice of the energy pie.

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