Study On The Influence Factors Of Biological Nitrogen Removal Of Acrylic Fiber Wastewater

Acrylic wastewater is a high concentration of refractory organic wastewater which is typical in polymer materials industrial wastewater、toxic wastewater and high ammonia nitrogen wastewater treatment. It has such characteristics as high concentration of organic pollutant Polymer Powders and oligomeric are difficult to biodegrade 、the component is complexment、has toxic C yanide in water and the nitrogen substance in water will resolve high concentration ammonia nitrogen in treating process,how to effectively remove the ammonia nitrogen in the acrylic fiber wastewater and make it discharged with the corresponding standard has become a difficult problem of scholars who paid high attention to, So the research of acrylic wastewater biological nitrogen removal influence factors and improve the efficiency of denitrification has very important practical significance.The object of this research is the crylic fiber wastewater of JiLin Q iFeng C hemical Fiber limited company, using pilot-scale sequencing batch biofilm reactor(SBBR) process, contrasting the effect of denitrification removal from the biochemical treatment by changing the operating conditions such as HRT 、 DO 、 C/N 、 temperature 、 alkalinity 、phosphorous concentration、the way to operate and the COD concentration, to analyze the regularity of carbon and nitrogen compounds in crylic fiber wastewater degradation under different conditions, to determine the optimum parameters. And referencing the actual operation conditions in the factory, to treate the waste water which is mixed the crylic fiber wastewater and the glue water, and find the reasonable operation condition, to make it discharged with the corresponding standard. The research mainly draw the following conclusions:(1) The study on the influential factors of acrylic fiber wastewater biological nitrogen removal experiment using static single factor experiment through the SBBR reactor. It is concluded that the residence time HRT for 48 h, DO for 2-4 mg/L, 2 mg/L, dosing phosphate solution with sodium bicarbonate 0.4 g/L, the temperature of 25℃ under these best conditions, the COD and ammonia nitrogen in wastewater is 625~1232mg/L, and 85~140mg/L, the scope of effluent COD can be stable below 280 mg/L, ammonia nitrogen under 5 mg/L, nitrate nitrogen 52.41mg/L, nitrite nitrogen 0.14mg/L, total nitrogen 89.49 mg/L, BOD can be reduced to zero.(2) During the crylic wastewater biological denitrification mechanism research experiment, through the analysis of the measurement cycle degradation curve for each indicator, it is concluded that:①With a period in reactor residence times for 48 h for a cycle,a large of COD in acrylic wastewater can be adsorption degradated within 3h, during this time, part of the ammonia nitrogen is generated, Organics degradation of equilibrium concentration is about 30 h, ammonia nitrogen began to degrade after the COD for degradation completely, ammonia nitrogen completely degradation is about 30h; Ammonia nitrogen degradation process, the nitrite nitrogen rise, and then falling fast, Within the process of N itrification and nitrosation, he concentration of nitrate nitrogen continue to rise, after 30 h denitrification Occurred, nitrate nitrogen and total nitrogen degradate further, Total nitrogen content changed little, more difficult to remove, After HRT increases to 72 h, the COD and ammonia nitrogen are all in a certain degree of rise and treatment effect is poorer.②Under the condition of HRT for 48 h, DO for 2-4mg/L, 2mg/L, dosing phosphate 2mg/L, sodium bicarbonate 0.4 g/L, the temperature of 25℃, dissolved oxygen concentration、nutrients、basicity in the reactor and the temperature can guarantee the system occurred simultaneous nitrification and denitrification.③Under the condition of HRT48 h, the COD concentration for 696.4mg/L,the degradation process of COD obeying the first order reaction kinetics equation, obtained that the concentration of refractory organic is 245mg/L by calculation.(3) By comparing the effluent efficiency of different dilution ratio of mixed wastewater, It can reach that the system can reach to the adsorption capacity limits of COD,When the COD concentration for 400 ~ 500 mg/L, and the concentration range has a good effect of nitrification and denitrification, removal rate of effluent COD is 57.2%, removal rate of ammonia nitrogen is 95.83% and removal rate of total nitrogen is 9.4%, BO D can be reduced to zero.(4)The study on acrylic fibre wastewater and glue water coupling experiment, By comparing the effect of different dilution ratio of the Mixed wastewater, the results show that Coupling of two kinds of wastewater treatment is better than single treatment effect. When the blending ratio is 1:2, the concentration index Remove the best, Under this condition, the effluent COD concentration is 171mg/L, ammonia nitrogen concentration is 2.4mg/L. Combination with the engineering practice, in the case of the mixing ratio of 1:3, H RT 48h、HRT 24 h or HRT 48h(A24h/O24h) can make the effluent coupling wastewater COD < 60 mg/L, ammonia nitrogen < 10 mg/L.