Study On High COD And High Ammonia(Allantoin Process) Wastewater Traetment

Water is the source of life and also one of the most important substance to the survival of humans.However,with the development of human life and production,water pollution is becoming more and more serious,the contaminant is becoming more and more complex.A variety of contaminants is generated in production process wastewater such as energy,metallurgy,chemical and pharmaceutical and other industries.Allantoin is a kind of raw material in the chemical and pharmaceutical industry.And ammonia nitrogen waste water,organic pollutants and acidic waste water are generated in the production process of allantoin.The concentration of COD_Cr is over 527 thousands milligram per litre,the concentration of ammonia nitrogen is more than 24.3 thousands milligram per litre,and the concentration of total nitrogen is more than 107 thousands milligram per litre,the value of pH is less than 1.It is very rare that so high COD_Cr and ammonia nitrogen waste water like allantoin process waste water in the general industry and the present actual discharge of sewage.What is more,the treatment is very hard to achieve the three emission standards of “the Discharge Standard of Integrated Wastewater”(the concentration of COD_Cr is below 500 thousands milligram per litre,and the concentration of ammonia nitrogen is unlimited).The pollution characteristics and hazards of the allantoin process wastewater were analyzed in this paper.In order to be convinced,study of highly concentrated organic wastewater and high ammonia wastewater treatment were checked at home and abroad.Based on this,advantages and disadvantages of different methods ware compared.Finally,the combined process of Calcium oxide-Iron microelectrolysis-Coagulation-Magnesium ammonium phosphate precipitation-Anaerobic biochemical-Biological contact oxidation was adopted in the treatment of allantoin process waste water by a lot of exploring experiments,optimization experiments and repeated trials.The concentration of COD_Cr was 527 thousands milligram per litre,the concentration of ammonia nitrogen was 24.3 thousands milligram per litre,the concentration of total nitrogen was more than 107 thousands milligram per litre,after the pretreatment of allantoin process wastewater by chemical and physical methods,the effluent COD_Cr concentration was 124 thousands milligram per litre,the effluent total nitrogen concentration was about 41.2 thousands milligram per litre,the effluent ammonia nitrogen concentration was 2.63 thousands milligram per litre,afterwards the effluent was mixed with sewage,Anaerobic biochemical and Biological contact oxidation process was applied to treat depth,the effluent COD_Cr concentration was less than 450 milligram per litre,it reached the three emission standards of “the Discharge Standard of Integrated Wastewater”.Throughout the process,the removal of COD_Cr was 99.9%,the removal of total nitrogen was 96.2%,the removal of ammonia nitrogen was 84.0%.The effluent of high COD_Cr and high ammonia nitrogen?allantoin process?waste water reached the three emission standards of “the Discharge Standard of Integrated Wastewater” through pretreatment and biological treatment.It has a great guiding significance in theory research and practical application for the treatment of high COD and high ammonia nitrogen wastewater,at the same time,it has important significance for the environmental protection,energy conservation,and sustainable development by using cheap iron to degrade organic matter in acidic medium and magnesium ammonium phosphate to recycle ammonia nitrogen.