| The mission for controlling the pollution of "coal smoke type" in our country is urgent because the economy loss resulting from 862 and acid rain amounts to thousand hundred million yuan every year; on the other hand, the plentiful household garbage is treated by filling into the grand, therefore it produces substantive poisonous and harmful organic waste water-landfill leachate. So how to handle, convert and make use of the landfill leachate becomes a new focus in the field of environmental protection.In order to treat both of the waste water and waste gas mentioned above, we base the study on reciprocal systems of flue gas wet desulfurization and microbial transformation of sulfur with landfill leachate. The paper focused on the selection and growth characteristic study of the sulfate-converting bacteria that include the sulfate-reducing bacteria and sulfur oxidizing bacteria. Some conclusions were listed as follows:1. A strain of sultate-reducing bacteria was isolated from the sullage of Sichuan Sulfate Factory. The cells are vibrioid-shaped or of thin rod shape with the size of 0.4~0.6 3.0~ 5.0 m . They are motile by single polar flagella and non-spore-forming. The cells strain Gram-negative.2. Two strains of sulfur oxidizing bacteria were isolated from the backwater of Fulan River. The cells of them were ovally shaped with the size of 0.5~ 1.0 1 .0~2.0 m. Both of the cells strainGram-negative and the colors of the anaerobic culture are green or red-brown, respectively.3. The optimum temperature of the strain(SRB) is 35 ,the optimum pH range 6.0 ~ 6.5, and it is not strictly anaerobic.4. During the vitriol dissimilation process, the strain (SRB) can use methyl alcohol, ether, lactic acid, glucose... etc. The efficiency of vitriol dissimilation process responds to the COD/ SO42~ value with direct ratio, but when the COD/ SO42- value is over and above 2.5 hereafter, its influence towards vitriol dissimilation process falls down. In the paper, the range of 2.0~2.5 is adopted as the COD/ SO42- value, and at this rate 55 percent of SO42- and 70 percent of COD are removed.5. The ingredients of the media were optimized, and the conclusion was drawn that KH2PO4 and NaCl play an important role during the growth of the strain (SRB). The influence of the Fe2+ on the strain was studied and the metabolism activity of the strain responds to the strength of Fe2+ with direct ratio, but when the concentration of Fe2+ exceeds 3~4g/l its influence on the strain falls down sharply.6. To improve the removal ratio of the sulfate, the strain (SRB) was cultivated in the anaerobic reactor, and the N2 was used to blow the H2S from the culture. At optimized conditions (pH, temperature, culture medium, etc.), 76% of the sulfate (1900mg/l) can be converted after five days.The paper try to provide a new idea to handle the environment problem: make the two pollutants (flow gas and landfill leachate) cooperate each other in the same engineering flow, and produce both social and economic benefit, therefore it represents a new concept of environmental and chemical engineering: treat the waste with waste. At the same time, the studying results provide a good basis for the further relating research in the reciprocal system.
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