Efficient pressure water scrubbing
One common biogas purification method is pressure water scrubbing, which is based on the physical effect of dissolving gases in liquids. Here, in an isentrope, two-phase process, the gas to be separated is first compressed under pressure, as the solubility of the gas increases with increasing pressure. The compressed gas is then injected into a washing solution, a liquid absorbing agent. Here the gas is absorbed by the liquid.
Scientists of the Engler-Bunte-Institute (EBI) at KIT have developed an energy-efficient method that significantly reduces the compression effort required for pressure water scrubbing. The single-phase method centers on the simultaneous progression of compression and absorption. To densify the gas, it is fed into a reciprocating compressor fitted with a atomizer. During compression, the washing solution – in this case water – is injected into the gas to be absorbed in the form of droplets. Atomization accelerates material transport through an increased exchange surface. With their large heat capacity, the droplets act as an energy store for sensible heat.
In comparison to conventional, two-phase pressure water scrubbing, the compression effort can be reduced by around 40 % with the new method: on the one hand through the permanent reduction of the volume of gas to be compressed or absorbed, and on the other through almost isothermal compression.
The method can be applied to all water-soluble gases and was tested in an experimental plant at the Institute. KIT is seeking partners for joint development projects and for industrial application.
Your contact person for this offer
Dr. Aude Pélisson-Schecker,
Karlsruhe Institute of Technology (KIT)
Innovation and Relations Management (IRM)
Phone: +49 721 608-25335