Biomass Gasification Technology Assessment

The goal of the technology assessments has been to solicit and review the technical and performance data of gasifier systems and develop preliminary capital cost estimates for the core equipment. Specifically, the assessments focused on gasification and tar reforming technologies that are capable of producing a syngas suitable for further treatment and conversion to liquid fuels. In order to improve confidence in the predicted economics of these technologies, a thorough understanding of the basic capital cost and engineering requirements for gasification and tar reforming technologies was necessary. These assessments can be used by NREL to guide and supplement their research and development efforts.

As expected, it was very difficult to obtain detailed information from gasification and tar reforming technology vendors. Most vendors were not interested in sharing confidential cost or engineering information for a study of this nature. However, HGI managed to gather sufficient information to analyze three gasification and tar reforming systems as follows.

Technology 1

• Gasifier - feed rate of 1,000 oven dry metric tons/day of wood residue composed of wood chips and bark, using oxygen blown autothermal (partial oxidation) bubbling fluidized bed design.
• Tar Reformer - reactor vessel filled with solid catalyst blocks designed to crack tars. Oxygen blown for partial combustion of syngas to provide heat.
• Total Project Investment Cost - $ 70,590,000 (2011 dollars).

Technology 2

• Gasifier - feed rate of 1,000 oven dry metric tons/day of wood residue composed of wood chips and bark, using allothermal (indirect heating) circulating fluidized bed design. Heating of bed media occurs in a separate combustor by combustion of char with air.
• Tar Reformer - allothermal bubbling fluidized bed design.
• Total Project Investment Cost - $ 59,700,000 (2011 dollars).

Technology 3

• Gasifier - feed rate of 1,000 oven dry metric tons/day of wood residue composed of wood chips and bark, using oxygen blown autothermal (partial oxidation) bubbling fluidized bed design.
• Tar Reformer - unknown technology.
• Total Project Investment Cost - $ 70,720,000 (2011 dollars).

This report summarizes the equipment, general arrangement of the equipment, operating characteristics and operating severity for each technology. The order of magnitude capital cost estimates are supported by a basis-of-estimate write-up, which is also included in this report.