Dutch biomass gasification process comes on line

By Ryan C. Christiansen
The Energy Research Center of the Netherlands has completed an 800 kilowatt-hour pilot-scale gasification plant based on its Milena gasifier technology, which uses an indirectly heated biomass gasification process with high cold-gas efficiency and a high methane yield, and is optimized for the production of substitute natural gas.

According to Christiaan van der Meijden, a researcher with the center's Biomass, Coal & Environmental Research division, the primary feedstock for the pilot plant is waste wood. "We plan to test other biomass fuels, as well, [such as] sunflower husks," he said. The green gas produced by the pilot-scale plant will be used to fuel one of several natural-gas-powered consumer automobiles currently available in Europe, he said.

The next step will be to begin construction of a 10-megawatt demonstration plant in 2009. "Several industrial parties are interested and involved in parts of the development," van der Meijden said. "We have not licensed the Milena technology yet." However, he added, the technology will become commercially available after the demonstration.

The demo plant will initially produce gas for a boiler. Later, it will include an oil gas scrubber tar removal system developed by the Energy Research Center to recycle tar for combustion to produce green gas. Ultimately, the plant will be equipped with a gas cleaner to produce substitute natural gas at grid specifications. "The technology to have the gas on specification for gas grid injection or use as [biobased compressed natural gas] should be ready for commercialization in 2015," van der Meijden said.

Because the carbon dioxide stream that is produced during substitute natural gas production will be stored in empty natural gas fields, the overall process will produce a carbon-dioxide-negative result, van der Meijden said.