| 摘要 |
A trickling filter removes hydrogen sulfide from gas, preferably using heated digester effluent for nutrients and neutralization. Biogas produced from an anaerobic digester, and containing H2S, is pumped or sucked through the trickling filter tank, which comprises at least a portion that is packed with media(s) and sealed to prevent unplanned entry of air. In said system, gas flows up through the filter as a preferably heated digester effluent solution trickles down. A further feature of the preferred embodiments may be that digested manure is used to neutralize acidic scrubber by¬ product, for example, by mixing of excess filter tank nutrient flow with digested manure prior to its return to the anaerobic digester outfall. The preferred embodiments may comprise nitrifying the scrubber, as the scrubber may also provide a home for nitrifying bacteria that will convert a portion of the circulating ammonia to nitrate. A preferred cleaning technique comprises filling the filter/tank with water, allowing floatable media to float, and aggressively/rigorously agitating the media, for example, by injecting liquid or gas through nozzles mounted in the tank to loosen bacteria and sulfur. |
