GB931024A - Improvements in or relating to processes of treating contaminated waters - Google Patents

Abstract

931,024. Purifying water. SUN OIL CO. June 1, 1960, No. 19442/60. Class 46. In a process in which fresh water is taken from a suitable source of supply through line 1 and is fed to boilers or other generating means 2 and 4 and condensate from such heating and power units which has come in contact with contaminants such as lubricating oil is taken off through line 6 and mixed with other plant water streams, eventually flowing into oil separator 17 and being collected in basin 20, the water from basin 20 is passed to the cooling towers 23 via return line 27 as the temperature in the line is also ideal for bacterial growth and the high degree of aeration obtained in the towers is exceedingly favourable for bacterial oxidation. In case the water from impounding basin 20 is insufficient to furnish make-up water for the cooling towers, fresh water may be introduced through line 24 in an amount sufficient for that purpose. The water from the cooling towers is circulated to coolers and condensers 25 through line 26 and is returned to cooling towers 23 through line 27. Circulation of the water is continued until an equilibrium amount of dissolved solids is built up in the water after which a regulated amount of cooling tower blowdown water will be removed from cooling towers 23 through line 28, a portion thereof being deflected through line 29 to crude oil desalter 30. Water from desalter 30, which will contain only a small amount of entrained oil and water soluble phenols is taken through line 31 and mixed with the balance of the cooling tower blowdown water, and then passed to oil separator 32, oil being withdrawn therefrom through line 33 and effluent water for discharge to the sewer through line 34. U.S.A. Specification 2,899,385 is referred to.