METHOD OF PHOSPHORUS RECOVERY

摘要

PROBLEM TO BE SOLVED: To provide a method for recovering phosphorus by which phosphorus included in the digested sludge of org. waste can be efficiently recovered with high purity. SOLUTION: Digested sludge 13 is supplied to a membrane separation tank 2 and subjected to liquid-solid separation by a membrane separation device 5 disposed in the tank 2 while controlling at least either temp. or pressure to a property controlled value higher than that of an anaerobic fermentation process. The liquid 15 which has permeated through the membrane is introduced to a MAP granulating device 3 and mixed with a magnesium chloride soln. 16 introduced into the device. Thus, the phosphorus component in the permeated liquid 15 is precipitated with the ammonium component as magnesium ammonium phosphate crystal grains 17.