Biogas is brought into intense contact with a circulating alkali liquid over a packing media in a single stage counter current process (gas Scrubber). The H2S in the gas is absorbed by the alkali liquid through various chemical reactions. Ultimately the H2S in the gas is almost all converted into NaHS using sodium hydroxide. The process is controlled by a sophisticated H2S detection and sampling system for efficient operations and low chemical consumption. Selective desulphurization is possible due to the differences in the physical and chemical properties of H2S and CO2. The course of this chemical process is also determined by the gas speed, chemical concentrations. pH values and the temperature and pressure of the system. Caustic consumption saving can be up to 60 per cent of the cost of conventional caustic scrubber technologies.



• simple, compact and robust construction;
• low capital cost;
• very flexible operating parameters;
• simple low cost operation and maintenance;
• low consumable usage;
• no chemical waste;
• economically viable for sulphur loads up to 10 – 25 tons a day depending on local site conditions
• equipment assembled as transportable units
• Modular construction in optional insulated housings.
We have reference sites in the UK, China, Russia, Belgium, Netherlands.