Research Of Microbial Transformation For Sulfur In Waste Water Of Landfill Leachate

The mission for controlling the pollution of "coal smoke type" in our country is urgent because the economy loss resulting from SO2 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 sulfate-oxidizing photosynthetic bacteria. Some conclusions were listed as follows:A strain of sulfate-oxidizing photosynthetic bacteria was isolated from city back-water. The cells are thin rod shape with the size of 1.0～1.0×2.0μm . They are flagella and non-spore-forming. The cells strain Gram-negative.The separate bacteria belongs to the middle bacteria. The optimum temperature of the strain(PSB) is 30 ℃ ,the pH range 6.0 ～ 9.0, the optimum pH is 8.0, and it is strictly anaerobic, and the optimum sunlight is 1500lux , and chlorophyll a is the main photosynthesis pigment. It is considered to be Chromatium minutissimum. When oxidizing sulfide ,the strain can use lactic acid , citric acid and sodium bicarbonate , but it can not utilize acetic acid , ethanol and glucose and when utilizing the source of nitrogen , the separate bacteria can fully utilizing NH4+ ,but it can utilize NO2—,NO3— and carbamide .Through increasing the environment concentration of sulfide step by step around the strain, in order to increase the adapt ability to sulfide, the bacteria can grow well in 1000mg/l concentration of sulfide .The separate bacteria has no much request to nutrition. If provided sunlight, the strain can grow well in the waste which is dealed with first by SRB.Through discussed the mode to treat waste-water included high concentration of sulfate organic by the strain and SRB .it is know that PSB and SRB treat together is better than treat singly, although it will increase corresponding investment cost.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.