摘要 |
<p>1490897 Removal of hydrogen sulphide from waste fluid UNION CARBIDE CORP 25 April 1975 [26 April 1974] 17169/75 Heading ClC The invention comprises a method for removing H 2 S from both gas and liquid phases of aqueous BOD-containing waste fluid comprising the steps of: (a) separating the H 2 S-containing waste fluid into waste water and waste gas; (b) contacting the separated H 2 S-containing waste gas from (a) with H 2 S-low water in a liquid-gas flow ratio of at least 545 lb. moles liquid/lb. mole gas, absorbing said H 2 S in the water and discharging the H 2 S-depleted waste gas; (c) mixing said waste water from (a) and H 2 S- containing water from (b) with activated sludge and at least 50% by volume oxygen gas in sufficient quantity to provide dissolved oxygen concentration of at least 2 p.p.m. in an enclosed aeration zone and simultaneously recirculating one fluid against the other fluid for sufficient duration to chemically remove the H 2 S by oxidation and biochemically oxidize the BOD thereby forming oxygenated liquor; (d) separating the oxygenated liquor into activated sludge and purified water; and (e) recycling at least part of said activated sludge to said enclosed aeration zone of (c).</p> |