Research Sulphate Control In Anaerobic Biotreatment Penicillin Wastewater

Desulfurization process under anaerobic conditions of anaerobic expanded granular sludge bed (EGSB) reactor for treating penicillin waste water was systematically investigated.Firstly, the test analyzed the characteristic of antibiotic wastewater particularity. The result shown that:①The penicillin wastewater contains high concentration of toxic substances such as sulfate, excess nitrogen and poor anaerobic biodegradability. (COD:N: P about 200:43.37:0.78 and BOD/COD about 0.26) It is obvious that some factors of inhibiting anaerobic digestion in the wastewater.②Sulfate concentration have strong effect on the anaerobic digestion. Along with the sulfate concentration increased, COD removal rate decreased gradually. When the sulfate concentration above 5000mg/L and COD/SO42-<1, anaerobic degradation have been seriously inhibited.The study of the sulfate impact in penicillin wastewater treatment shown that no desulfurization unit in the circumstances, when the sulfate concentration about 2000 mg/L, COD/SO42- under 3, the reactor operating results and stability deterioration. Penicillin wastewater actually exceeded this threshold, it must be taken to a certain degree of desulfurization technology control Sulphate Inhibition. At this point, under certain conditions on the reactor EGSB organic load, under anaerobic conditions using the way of adding nitrates to the influte water to cultivate desulfurization bacteria, Will be transformed sulfide ions into harmless sulfur, EGSB which take inhibition on the process of EGSB treatment high-sulfate wastewater. And EGSB reactor influent COD concentration reached 6000mg/L sulphate concentration of 2400mg/L. When the EGSB-desulfurization System penicillin wastewater the result shown that:When the system was operated at 100%penicillin wastewater influent, and COD no less than 6000mg/L, organic loading 12kgCOD/(m3·d), COD/SO42- value no less than 2.5, liquid upflow velocity 2.2 m/h, then the COD removal efficiency higher than 85%, SO42- removal rate reached more than 80%, It can be seen under anaerobic conditions such desulfurization technology to control the inhibitory effect of sulfate and EGSB reactor reached stable operation conditions.Along with the EGSB's operation, the granular diameter in the bottom of the sludge bed were larger than that in the upper part of the sludge bed. Observed under the scanning electronic microscopy, we found that in the early time, there was distinct predominance of Methanosaeta. Along with the organic loading increased, it was appeared not the Methanosaeta but the Sarcina-type bacteria. In stable operation at medium, the granules had more microbe species. On the Methanosaeta and Sarcina-type bacteria, there are many Methanobacterium and Desulfovibrio congregated developed. Increase the Desulphurization Plant, the biggest difference is that the internal flora in the sludge increase in the number of bacilli.In the desulfurization reactor to run the course, with the growth of running time, sludge from mainly of filamentous bacteria in the early run into bacillus dominated later, especially after the Penicillin wastewater input the reactor, A large number of bamboo-shaped bacilli were arranged in fascicular sludge internal With the increasing of Sulfide's concentration in the influte wasterwater, some light yellow metallic S particles appear in the sludge surface, and Some sulfur precipitation occurred at the bottom of water.