| 摘要 |
A method for the removal of hydrogen sulphide from a gas comprises the steps of (i) contacting the gas with ferric hydroxide in water within a reactor under anaerobic conditions at a suitable pH and (ii) maintaining the ferric hydroxide concentration in the reactor at a predetermined value. The gas may be biogas generated during the digestion process of sewage sludge, and may be contacted with the iron hydroxide in situ. The pH may range from 5.5 to 9.0. The concentration of the ferric hydroxide in the reactor may by at least 5g/m3 and maintained by feeding additional amounts into the reactor at least once every 60 days. Also disclosed is a composition for use with the method which comprises a solution of ferric hydroxide in water wherein the solution comprises at least 8% ferric hydroxide expressed as iron on a dry basis and a minimum of 0.5% solids on a weight/volume basis. |
