The Energy Independence and Security Act of 2007 established a goal of 36 billion gallons of biofuels by 2022. Today, just 12 billion gallons are produced annually in the U.S. Closing this gap will require innovation in the entire biofuels supply chain, not just feedstocks. 

ThermoChem Recovery International, headquartered in Baltimore, Md., is commercializing the conversion of biomass into a broad range of end products. The company has developed proprietary gasification technology for both liquid and solid biomass that allows biorefineries to be feedstock-flexible in converting biomass to fuels, chemicals, power and energy.

The gasification process involves extreme temperatures to convert materials containing carbon, such as coal, petroleum coke (petcoke) or biomass, into synthesis gas. This so-called syngas has half the energy density of natural gas, and can be burned directly in boilers, internal combustion engines or gas turbines for power generation. It also can be used as an intermediate to produce other chemicals such as hydrogen and methanol. By using the Fischer-Tropsch process, it can be transformed into a synthetic petroleum substitute.

The temperatures at which gasification occurs, typically above 850 degrees Fahrenheit, drastically limit the available sealing options. When TRI was developing its initial commercial-scale units, there was no compressible sealing material suitable for use in this process. Graphite-based gaskets begin to oxidize above 850 degrees, eventually leading to rapid leakage. The only other option was a metal-sealing solution that required an extremely high-surface finish and higher-than-achievable bolt load requirements. This escalated the sealing costs of the project, and in one instance required on-line leak sealing when this gasket leaked.      

Subsequently, TRI began working on a pilot facility in Durham, N.C., to demonstrate the feasibility of producing syngas, Fischer-Tropsch diesel fuel and high-value paraffin waxes from a wide range of biomass feed stocks. Its fully integrated design included a biomass feeding and gasification system, primary gas clean-up, syngas compression, secondary gas clean-up and Fischer-Tropsch liquids and wax production.

TRI took its performance requirements to Palmyra, N.Y.-based Garlock Sealing Technologies, which concurrently was engaged in a development program for an ultrahigh-temperature gasket for service in applications with temperatures ranging from 850 to more than 1,800 degrees. These gaskets would potentially solve many of the fluid sealing problems encountered in the Norampac project in Niagara Falls, N.Y., which included the need for a high surface finish on industrial flanges and the ability to accommodate lower bolting loads on the gasket. TRI and Garlock Sealing Technologies collaborated on testing hundreds of these new gaskets in an extremely demanding application for an extended period of time. Garlock Sealing Technologies regularly visited the TRI plant to confirm the gaskets were performing as designed and to gather feedback for further improving their performance.

TRI has since been able to successfully demonstrate the production of syngas, diesel fuel and paraffin waxes at its pilot plant, and is currently involved in the development of several large-scale, commercial projects. The first is the Flambeau River Biofuels project in Park Falls, Wis., a demonstration biorefinery. When completed, it will gasify 1,000 dry tons of woody biomass per day to produce renewable hydrocarbon fuels, electricity and steam for the host paper mill. The second is NewPage Corp.’s biorefinery in Wisconsin Rapids, Wis., which is capable of gasifying 500 dry tons of woody biomass per day for hydrocarbon fuels and steam for the host paper mill.

Garlock Sealing Technologies recently commercialized its extreme-, high-temperature gaskets used in these projects. Trademarked THERMa-PUR, they are designed to seal connections in applications with extremely high temperatures. By working closely with TRI, the company was able to field test and verify that its new gaskets exhibited long-term, reliable sealing.

The gaskets are made of a proprietary, nonoxidizing material with low organic fiber content and a flexible fiber core, allowing them to withstand extremely high temperatures, both continuous and in thermal cycling conditions. They also provide hydrophobic and electrical insulation properties to resist moisture absorption and the potential for galvanic corrosion between flanges of dissimilar metals.

Collaborations such as the one that facilitated Garlock Sealing Technologies’ ability to produce its new gaskets can help reduce the cost of commercializing renewable energy projects by providing the necessary supporting technologies and innovative solutions to challenges. As a result, the nation will be able to accelerate biofuel production, close the gap between targeted and actual levels, and move us all closer to energy independence and a greener future.   

Author: Sherwin Damdar
Senior Product Engineer, Garlock Sealing Technologies
(315) 597-4811
Info@Garlock.com

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