The THIOPAQ® was developed by Paques, in cooperation with universities, research institutes and customers. It can be applied to a wide range of biogas streams containing H2S and can be combined with all biological anaerobic systems. The ‘caustic’ solution in the THIOPAQ® scrubber is continuously biologically regenerated. In the scrubber, the gas containing H2S is brought into contact with the washing water in counter currently. Absorption of H2S under slightly alkaline conditions (pH 8-9) enables a chemical reaction with hydroxide ions.
The hydroxide used in the scrubber is regenerated in the bioreactor. The system obtains a very high H2S removal efficiency, exceeding 99,5%. Both the small bleed stream (consisting of sodium salts) and the produced sulphur are free of sulphide, so discharge is no problem.
After treatment in the THIOPAQ® scrubber, the biogas can be used in a gas engine or boiler of can be transported in a local micro gas grid. Upgrading to biomethane, which can be brought into the gas distribution network of use as fuel for vehicles is another possibility. The elemental sulphur, produced by the THIOPAQ® can be used as a high quality fertiliser.
The THIOPAQ® process explained
For more information about THIOPAQ, visit PAQUES’ website.