(64c) A Bench SCALE BIOMASS to Liquid Facility
AIChE Spring Meeting and Global Congress on Process Safety
2012
2012 Spring Meeting & 8th Global Congress on Process Safety
Emerging Technologies in Clean Energy for the Twenty-First Century
Biofuels from Lignocellulosic Biomass
Tuesday, April 3, 2012 - 9:00am to 9:30am
A bench scale biomass to liquid (BTL) facility was built and successfully commissioned.
A fixed bed biomass gasification facility is used to generate wood gas with capacity of producing up to 10 normal cubic meters of gas from agricultural and forestry waste such as straw and woodchips. The syngas (Carbon monoxide and Hydrogen) content in the biomass gas is between 20 to 40% by volume when operated at ambient pressure and with air as the oxidizer. The gas with a temperature of over 700 C is then cooled in a quench / water scrubber. Most the mechanical impurities, tars, water soluble inorganic particles are also removed in this process. The gas then passes through a condenser to separate most of water, a dryer filled with corn cobs to further remove water and solid and liquid impurities before it is compressed to over 100 barg into cylinders to be used for Fischer Tropsch section.
The gas from the cylinder is further cleaned to remove sulphur and oxygen. The specific sulphur removal process is applied to lower the sulphur content of the gas to less than 10 ppbv, which is the detection limit of the sulphur analyser used. The chosen sulphur removal technology applied some modified activated carbon to adsorb H2S with the help of hydrolysis reaction to convert organic sulphur impurities into H2S. It has been shown that during the commissioning and operation period, which was a 3 month period, the deep sulphur removal process performed as required.
100 grams of supported cobalt catalyst is loaded in the inner tube of the double-tube fixed bed Fischer-Tropsch reactor. The inner diameter of the inner tube is 50 mm. Heated oil runs in the shell side of the reactor during normal reaction (for cooling purposes), which runs at temperatures lower than 250 C, while nitrogen is used in the shell side during reduction, which runs up to 350 C. The Fischer Tropsch reaction was carried out at different pressures and temperatures.
Liquid and wax products were produced from the facility and the properties of the produced liquid and solid hydrocarbons are the same as Fischer Tropsch products from other feed stocks such as natural gas and coal.