| 摘要 |
1393725 Treating waste liquids DEUTSCHE TEXACO AG 20 April 1972 [11 May 1971] 18326/72 Heading C1C A method for treating sour water containing ammonia and hydrogen sulphide, and spent lye containing phenol and a base (e.g. potassium carbonate or hydroxide), comprises stripping the sour water in a first stripper to produce ammonia-containing vapours, scrubbing the ammonia-containing vapours with a strong mineral acid in a mineral acid scrubber to produce a solution of the ammonium salt of the acid with simultaneous separation of hydrogen sulphide, mixing the spent lye with at least a portion of the ammonium salt solution and separating the mixture into phases, removing the phenol-containing upper phase and stripping the aqueous bottom phase in a second stripper, passing the vapours stripped in the second stripper to the mineral acid scrubber and passing the bottom product from the second stripper to the first stripper. The bottoms product from the first stripper constitutes the treated water, which can be further treated biologically. A spent phenol-free alkaline liquor may be added to the mixture of spent lye and ammonia salt solution for treatment therewith in the second stripper. The method may comprise a step of feeding part of the ammonia salt solution to the first stripper. The mineral acid may be sulphuric, hydrohalic or phosphoric acid. The sour water may also contain mercaptans and carbon dioxide. The vapours stripped in the second stripper may comprise ammonia, hydrogen sulphide and mercaptans.
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