| With the development of the society, more and more different kinds of industrial pollutants are discharged. For the moment,people and all levels environment protection departments pay more attention to the treatment of waste water which concludes high concentration organic contaminations, ammoniate and nitrification, suspended compounds. Similar with other types of waste water, the processing method mostly conclude physical-chemical process and biological treatment. Among all these methods the anaerobic treatment process was used extensively for hereinafter merit:(1)fewer excess sludge;(2)the biological sludge is apt to dehydration;(3)fewer required alimentation;(4) no energy is required for aeration;(5) the end outcome --methane is useful;(6) running under upper load;(7) active anaerobic sludge can be preserved several months. Ghosh and Pohland putted forward the two-phase (segment) treatment when people got more knowledge of the anaerobic process. It namely means that the waste water was treated in two different reactors to part the different microbe groups that require different environmental conditions in the anaerobic process. The first phase is the hydrolysis and acidification phase where the dominant microbes are hydrolysis and ferment bacteria, acid formers. In this phase, complicated organic substrates were metabolized into dextrose, amino acid, fatty acid and glycerin first, then, were fermented into kinds of organic acid. There are lots of this type bacteria, that can efficiently metabolize, quickly reproduce, the shortest doubling time only several quarters,and are not sensitive to the change of environmental condition. The second phase is mainly operated by hydrogen and acetic acid formers, methanogenic bacteria. They turn the organic acid into acetic acid, ultimately make them to be methane. This type microbe are comparatively less, slowly reproduce, doubling time from 10h to 6d , and are sensitive to the environmental condition such as the pH, temperature, toxicant, et al. The substrates that can be used are also limited. At present research of hydrolysis and acidification craft mostly focuses on moderate temperature bacteria ( 35℃) and thermophilic bacteria(55℃),then hardly on the extreme temperature bacteria(70℃).There's no report about it in China. In this paper, the hydrolysis and acidification of high organic concentration wastewater was separately studied under three kinds of conditions--moderate temperature bacteria(35℃), high temperature(55℃)and extreme temperature(70℃). Then discussed the effects of the extreme temperature(70℃) hydrolysis and acidification art and decided the arts parameters. The research was divided into four parts: 1. Compared the effects of the hydrolysis and acidification under the three temperature conditions; estimating the effect with acidification ratio; 2. Discussed the influence of nitrogen, sulphur, pH value, alkalinity on the hydrolysis and acidification. 3. Supervised the quantity and content of each element of VFA, to decide the important arts parameter—HRT. 4. Cultured, separated and discriminated the bacteria. The results indicated: 1. Temperature is a main factor for the hydrolysis and acidification process. The extreme temperature art obviously preceded others two, the content of VFA increased to 5.1 times, acidification ratio (VFA/COD×100%) equaled to 28.5%. While the content of VFA under the 35℃and 55 ℃conditions only increased to 2.19 times and 2.61 times; acidification respectively equaled to 15% and 15.8%. Compared synthetically, the increasing ratio and acidification ratio of 70 ℃hydrolysis and acidification art are evidently better than others two. The COD removal of these three arts were all under 25%, but 70 ℃> 55 ℃> 35℃. 2. Under each temperature condition, the pH value of the system was depressed with the increasing of VFA. While the most VFA increasing of 70℃, the smallest change of pH value, the lowest pH value of the system was 5.31. Analysis synthetically, the higher SO42-removal and more alkaline production of proteolysis resulted in the cushion of the pH value. In addition, through the foundation of the buffer, the acid-base balance in the reactor could be controlled. During the captive test, according to the content of the starch waste...
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