| With the development of the industry, heavily use of coal will inevitably generate pollution, and removing the industrial wastewater is a kind of very difficult thing. Not only the amount of organic matter, and many ammonia salt, but also small part of the thiocyanate and nonpolar pollutants. The main way of the degradation of coking wastewater is biological nitrogen removal process, which is the largest use of activated sludge process. This technology is mature, the cost is very low, but the drawback is obvious, it is difficult to effectively remove the refractory organics and ammonia, in order to meet the national emission standard. Therefore, many domestic and foreign researchers began to consider by bioaugmentation technology and improvement of coking wastewater treatment process, so as to solve the traditional process of ammonia nitrogen、 COD treatment difficult problem.In this experiment, through the acquisition of coking plant wastewater treatment by the first activated sludge aeration pool. Firstly, enrichment, separation and purification was obtained after removal of ammonia nitrogen, named Y1. Then the strain on the physiological and biochemical experiments and has carried on the preliminary identification of bacteria using modern molecular methods, finally get the conclusion that the strain was identified as Acinetobacter, named:Acinetobacter sp.Y1. Analysis of bacterial nitrification performance was detected by culture medium of ammonia nitrogen、nitrite nitrogen nitrate nitrogen%total nitrogen.The immobilization of the screened strain Y1, immobilized methods are very common, which mainly use the embedding method, using PVA(polyvinyl alcohol)、sodium alginate、agar and PVA+sodium alginate as entrapment carrier. Comparing these four kinds of carrier of immobilized beads made by physical and chemical properties, Considering the physical properties:sodium alginate is most easily to form the ball、followed by PVA and PVA+sodium alginate, agar is relatively difficult to form a ball. Considering the chemical properties:sodium alginate and PVA+sodium alginate as entrapment carrier making the ball, in the removal of ammonia nitrogen and total nitrogen is better than PVA and agar content place of immobilized carrier, After5days of culture in the shaker, the degradation of ammonia to reach the national discharge standard of two grade, The total nitrogen removal rate reached64.17%. However, because of the sodium alginate as entrapment carrier.Compared to the PVA, immobilized ball formation as the carrier easily broken, therefore, the final selection of the sodium alginate+PVA as embedding barrier immobilized beads is best.Comparison of ammonia nitrogen removal capacity of immobilized and suspended bacteria liquid, Ammonia nitrogen removal rate of immobilized beads for ammonia nitrogen rate is significantly better than the bacteria suspended in solution. When the initial C/N is less than14, ammonia removal rate increases with C/N increasing; when C/N is14-18, ammonia nitrogen removal rate is two kinds of state change; when C/N is greater than18, the two state of ammonia removal rate gradually decreased. When pH is between7.7-9.1, ammonia nitrogen removal rate of two kinds of state of the best; when pH was5and11, suspended bacteria was inhibited and the ball can remove ammonia nitrogen. When the temperature is30℃, two kinds of state of ammonia removal rate is better; when the temperature is higher than40℃, bacteria liquid ammonia removal rate has decreased,while the ball is slow down. When the rotate speed is120r/min, two kinds of state of ammonia removal rate is better, however, the rotate speed is more than120r/min, the removal rate of ammonia nitrogen is changed little. |
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