Novel L-aspartic acid waste water recycling utilization process

Abstract

The invention provides a novel process for circulating and reusing L-aspartic acid wastewater, belonging to the technical field of wastewater treatment and reuse. L-aspartic acid wastewater is nano-filtered at a temperature lower than 45 DEG C and with the operation pressure between 1.8 and 20 MPa, which can remove more than 98 percent of sulfate radical and more than 50 percent of ammonium ions; then nano-filtered concentrated solution is vacuum-concentrated so as to obtain crystals with main composition as ammonium sulfate; and nanofiltration clear liquid containing partial ammonium ions is directly circulated in L-aspartic acid production ingredients and / or is treated through a reverse osmosis membrane, and then is used as boiler steam water. The process thoroughly solves the ammonia-nitrogen pollution problem of the L-aspartic acid wastewater. Meanwhile, as production water is hermetically circulated, zero emission is achieved, which greatly saves water resources. The whole process has the advantages of high treatment efficiency, low operation cost and little energy consumption.

Description

technical field

[0001] The invention belongs to the technical field of wastewater treatment and reuse, in particular to a new process for L-aspartic acid wastewater recycling treatment. Background technique

[0002] In the production process of L-aspartic acid, due to the addition of ammonia and sulfuric acid, waste water containing a large amount of ammonium sulfate will be generated. The pH value is low, only 3-4, and the ammonia nitrogen is high, reaching 10000-20000mg / L. The traditional treatment methods are: (1), sent to a large sewage plant for treatment, because of the high nitrogen and sulfur content in the wastewater, the efficiency of biochemical treatment is low, and the effect is poor, so it can only be processed in a small proportion; (2), vacuum Concentration, due to the large processing capacity, consumes a lot of energy. These two methods all have the problems of high one-time equipment investment, great difficulty, and high operating cost, and the treated w...