TREATING METHOD FOR WASTE WATER PRODUCED FROM OIL AND FAT REFINING PROCESS

摘要

PURPOSE:To secure a simple and assured treatment to obtain the prescribed concentration/fractionation component, by giving an adjustment to the alkaline solution exhausted through the refining process to the fixed pH to change the solution into the emulsion and then carrying out the fixed fractionating process by the semipermeable film. CONSTITUTION:An adjustment is given to the alkaline solution containing the waste water of the deoxygen process as the main component plus the waste water of the pressing process, deodorizing process, etc. adjusted when necessary to pH5- 9, and then the fatty acid soap, the fatty acid, the neutral oil and others are changed into emulsion. Then the waste water is treated by the semipermeable film to be separated into the neutral oil type emulsion concentration/fractionation component containing the n-hexane-soluble component and the transmission/fractionation component substantially containing no n-hexane-soluble component each. It is preferable to perform the treatment by the semipermeable film with the temperature of the waste water higher than the neutral oil, the fatty acid or the mixture of the mixture of the fatty acid soap. In addition, the fatty acid is recoverd when necessary out of the concentration/fracionation component through the fixed treatment.