Gas Processing

Depending on the type of available production of biogas and product gas as well as the planned gas applications (see Gas Production), BEST - Bioenergy and Sustainable Technologies GmbH will develop and implement practical techniques for the processing of product gas and synthetic gas.

• Cold gas purification of product gas
• Hot gas purification of product gas
• Synthetic gas processing

The cold gas purification is usually a multiple-level separation technology at temperatures below 200°C, whereby particles are separated in one stage and tar and other unwanted particles are separated in a subsequent second stage. Gas purification, such as that realised in Güssing and Oberwart, is to be investigated and optimised in multiple projects from BEST. The gas scrubbing allows for the efficient separation of various gaseous substances. The two-stage separation of ammonia, hydrogen sulphide and hydrocyanic acid is to be investigated in a pilot plant.

The hot gas purification in the temperature range from 400-750°C offers a promising alternative to processing techniques at 150-200°C and will thus be investigated in three different systems. For the operation of high temperature fuel cells, dust and sulphur compounds must be removed very efficiently. In a test assembly, the dust in the raw gas from the biomass power plant in Güssing is to be removed through a special filter and then separated through a firm adsorbent material containing sulphur. During the high temperature gasification in the staged gasification plant, the dust removal is to be examined at temperatures of up to 700°C in a side stream. Directly after the filtration, the gas is to be routed through a sulphur-removal stage and a catalyst.

The upgrade of the product gas to the quality level of synthetic gas requires special fine-purification techniques, which guarantee a low residual content of sulphur and chlorine compounds as well as critical tar constituents. The calibration of the ideal synthetic gas composition (CO/H₂) requires specific process steps of the catalytic gas conversion as well as the separation of carbon dioxide. In addition, various techniques on the pilot scale will be investigated.