| Black water means sanitary wastewater including urine and feces, which has high nutrient concentration such as nitrogen, phosphor, and is rich of organic contaminants, even carries some pathogens. It is a vital importance of water pollution and water point source pollution. Especially, its high phosphorus nutrient concentration is the potential hazard for water eutrophication. The water-saving black water micro-organism treatment system discussed in this paper is an independent system especially aims at decentralized point black water discharging. The system, which can treat black water in situ and use the outlet water recycle, makes use of microbial metabolism to remove high concentration nutritive salt (nitrogen and phosphor).PAOs, which are the main component in the system, are researched in this paper. The culturable of PAOs and its efficient to remove Phosphates has been enhanced by improving the culture medium. First, PAOs are plate cultured and the reason why PAOs are hard to culture is analyzed. Synergistic agent additive process is introduced. Three PAOs dominant colony are separated by streak culture. Growth curves of PAOs and the three colonies are measured by spectrophotometer. It has been found that metabolism and breeding of the three colony and PAOs are significant different by comparing to each other. In this foundation, research on improving culturable of PAOs and its efficient to remove Phosphates are carried on by using QC8500. The Pyruvic acid sodium salt, L-Proline, Keto-glutaric acid, andβ-Cyclodextrin are used as synergistic agents to improve culture medium. Growths promoting action of synergistic agents to PAOs and three dominant colonies, and the efficient promotion to remove Phosphates have been studied.Main conclusions obtained by experiments list as follows:PAOs show very high selectivity to culture medium. Difference in culture habitat, lack of nutrient and active material, change of collaborative style and ecological niche will all bring down its cultured capability. Three dominant colonies are separated by streak plate. Among them, colony-I assumes white snowflake, diameter between 2 and 4.5 mm. Colony-II assumes white sphere, and diameter between 2 and 3.5 mm. Colony-III assumes yellow ellipsoid, diameter between 1.5 and 2 mm.One metabolism period of PAOs costs 48 hours. Among three dominant colonies, colony I has highest cultured capability while colony III has the worst and colony I is endemic species in PAOs community in this system.Among four Synergistic agents, Keto-glutaric acid have growth inhibitory effects on PAOs, while others can promote the metabolism of PAOs, its tamableness and efficiency to remove phosphorus. On the opposite, Pyruvic acid sodium salt can obviously promote cultured abilities, growth rate of PAOs, and prolong its metabolism period. The concentration optimum of three promoting synergistic agents is among 0.001-0.005mg/l.Pyruvic acid sodium salt can be benefit for the growth of PAOs, whileβ-Cyclodextrin can raise phosphorus removal efficiency. When addβ-Cyclodextrin to the colony-I, the total phosphorus removal efficiency can be raised 23.8%. Meanwhile, the organic phosphorus removal efficiency can be raised 45.2% after addingβ-Cyclodextrin to the colony-III.Based on the water-saving black water micro-organism treatment system, the study had been aimed at cutting down the phosphorus concentration of black water in order to ease the problems of sanitary water point source pollution and have efficient benefits for the problems of eutrophication. Meanwhile, deal with the high phosphorus concentration of black water can bring benign development for wastewater resuscitation.
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