Regenerative Sulfur Removal from Biomass Gasifiers

The goal of the project is the development of a novel technique for removing hydrogen sulfide (H2S) from gasification gas at high temperature, up to 500°C, using a metal oxide absorber and subsequently regenerating the absorber when saturated.

The common industrial technique for removing high concentrations of H2S from gasification gas is by amine scrubbing, where the gas must be cooled to around 60°C. At this temperature, the water in the gas will condense out, and in order to perform the water gas shift reaction later in the process, the water needs to be added afterwards.

The H2S-regeneration technique will initially be developed and tested in laboratory scale. Later in the project, we will expose the absorber to H2S-rich gasification gas taken as a slipstream from the 15 MW gasifier at Skive Fjernvarme. Similar tests are planned with gas from the gasification facility in Piteå.

It is expected that with the implementation of the new high temperature sulfur absorber, the overall plant investment will be reduced by up to 10% and the energy efficiency increased by ~3-5% resulting in lower operation cost of the produced Synthetic Natural Gas (SNG) pr. cubic meter when compared to a plant utilizing amine scrubbing.