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The Study on Chemistry Assistant Biological Phosphorus Removal of A~2 /O Process

Author: WangGuanSheng
Tutor: LvBingNan
School: Harbin Institute of Technology
Course: Municipal Engineering
Keywords: A ~ 2 / O process Chemically enhanced biological phosphorus removal Polymerization ferroaluminum Poly ferric
CLC: X703
Type: Master's thesis
Year: 2010
Downloads: 171
Quote: 1
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Abstract

Of water eutrophication increasingly severe problem, people are increasingly concerned about water pollution increase, increasingly stringent effluent discharge standards developed by the national and local. Chemically enhanced biological phosphorus removal process is a highly efficient phosphorus removal process, and thus become a hot topic. A ~ 2 / O processing effects and chemical phosphorus removal microorganisms A ~ 2 / O process in order to study the chemically enhanced, the subject of a half life of sewage, half artificial sewage mixed with water was treated in the laboratory The simulation of chemically enhanced A ~ 2 / O phosphorus removal system. The test effects of different chemicals in different dosing point in different dosage strengthen the A ~ 2 / O phosphorus removal system. Under the experimental conditions, A ~ 2 / O nitrogen and phosphorus removal system optimization run COD removal better and more stable, are more than 80% removal efficiency. Sludge reflux ratio, internal reflux ratio and temperature have a certain effect on the nitrogen and phosphorus removal of the system, but the temperature effects play a major role. Internal reflux ratio of 1-2 between the elevated temperature is conducive to the removal of TN, national waste water discharge effluent TN basically reached an A standard. Under conditions of low temperature, A ~ 2 / O nitrogen and phosphorus removal system better TP removal. But only through basic biological phosphorus removal effluent TP between 1.5-2.6 mg / L, and occasionally 0.5mg / L or less. A ~ 2 / O nitrogen and phosphorus removal system only through biological phosphorus removal can not reach an A standard of the national sewage discharge assisted chemical phosphorus removal. A ~ 2 / O system aeration tank preceding dosing polymerization ferroaluminum TP removal effect is not increased with the increase in the amount of dosing. Under the experimental conditions, the the polymerization ferroaluminum dosage of 4mg / L, the removal of phosphorus best average effluent TP concentration of 0.77 mg / L. A ~ 2 / O system aeration tank last paragraph dosing polymerization ferroaluminum, removal increased with increasing dosage. Polymerization ferroaluminum dosage of 4mg / L, the average effluent TP concentration of 0.17 mg / L. Also found that under low temperature conditions (10 ° C), polymerizable ferroaluminum dosage of 2 mg / L, the system phosphorus removal better. Average effluent TP concentration of 0.08mg / L, the average removal rate of 98.96%. The low temperature helps TP removal. The topics also carried out on the physical and chemical properties of A ~ 2 / O system in microbial community structure of chemical phosphorus removal Pharmacy found that the to polymerization ferroaluminum smaller nitrifying bacteria, but the A ~ 2 / O process phosphate accumulating bacteria some impact. A 2 / O system aeration tank preceding paragraph cast plus polymerization ferroaluminum test by detection system sludge PHA (polyhydroxyalkanoate) content, found that the after dosing polymerization ferroaluminum phosphate accumulating bacteria of influential biological phosphorus removal. With the increase of the dosage, the impact of the enhanced role. And at the end of dosing pharmaceutical less impact on biological phosphorus removal system. In addition the polymerization ferroaluminum dosing, A / O nitrogen and phosphorus removal sludge age will be reduced, under the experimental conditions, the system sludge age reduced from 12-13 days to 10 days; sludge settled greatly improved, conducive to the separation of the mud; activated sludge microbial community structure changed. Poly iron strengthen the A 2 / O phosphorus removal systems research results show that: equimolar amounts of iron salts and aluminum salts strengthen the last paragraph in the aeration tank, A ~~ / O nitrogen and phosphorus removal system is basically the same removal efficiency. Iron salt molar mass is large, a large amount of chemicals needed, and relatively turbid effluent. But the price of iron salts and aluminum salts, and the need to consider the actual project.

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CLC: > Environmental science, safety science > Processing and comprehensive utilization of waste > General issues > Wastewater treatment and utilization
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