Purification of biogas of hydrogen sulfide, comprises removing washing phase impurities e.g. hydrogen sulfide from gas phase of biogas in scrubber using washing medium, and supplying washing medium containing sulfides to aerobic reactor

摘要

The method comprises removing a washing phase impurities such as hydrogen sulfide from a gas phase of biogas (12, 22) in a scrubber (10) at a basic level using washing medium (20), supplying the washing medium containing sulfides to an aerobic reactor (100), and converting sulfides contained in the washing medium to sulfuric acid and to carbon dioxide (CO 2) in a chemical way. The CO 2is drawn off from the aerobic reactor in a solution by the introduction of CO 2-free air for ventilation. The washing medium is wastewater and/or bio-sludge such as activated sludge. The method comprises removing a washing phase impurities such as hydrogen sulfide from a gas phase of biogas (12, 22) in a scrubber (10) at a basic level using washing medium (20), supplying the washing medium containing sulfides to an aerobic reactor (100), and converting sulfides contained in the washing medium to sulfuric acid and to carbon dioxide (CO 2) in a chemical way. The CO 2is drawn off from the aerobic reactor in a solution by the introduction of CO 2-free air for ventilation. The washing medium is wastewater and/or bio-sludge such as activated sludge and/or effluent of a sewage plant such as a sequencing batch reactor comprising bicarbonate. The aerobic reactor is supplied with oxygen and/or air, and alkalinity such as sodium hydroxide solution. The wastewater of the sequencing batch reactor and overflowing mediums of the aerobic reactor is again supplied to the reactor. The biosludge and/or the activated sludge and/or the effluent from the sequencing batch reactor and the aerobic reactor are circulated in the scrubber. The alkalinity in the scrubber is adjusted by the amount of circulating activated sludge and/or waste water such as activated sludge and/or wastewater from the sequencing batch reactor. An independent claim is included for a device for purifying biogas of hydrogen sulfide.