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Objective: To study the possibility of removing nitrogen, phosphorus, and organic pollutants using seeding type immobilized microorganisms., Methods: Lakes P and M in Wuhan were chosen as the objects to study the removal of nitrogen, phosphorus, and organic pollutants with the seeding type immobilized microorganisms. Correlations between the quantity of heterotrophic bacteria and the total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) in the two lakes were studied. The dominant bacteria were detected, inoculated to the sludge and acclimated by increasing nitrogen, phosphorus and decreasing carbon source in an intermittent, time-controlled and fixed-quantity way. The bacteria were then used to prepare the seeding type immobilized microorganisms, selecting diatomite as the adsorbent carrier. The ability and influence factors of removing nitrogen, phosphorus, and organic pollutant from water samples by the seeding type immobilized microorganisms were studied., Results: The coefficients of the heterotrophic bacterial quantity correlated with TOC, TP, and TN were 0.9143, 0.8229, 0.7954 in Lake P and 0.9168, 0.7187, 0.6022 in Lake M. Ten strains of dominant heterotrophic bacteria belonging to Pseudomonas, Coccus, Aeromonas, Bacillus, and Enterobateriaceae, separately, were isolated. The appropriate conditions for the seeding type immobilized microorgansims in purifying the water sample were exposure time=24 h, pH=7.0-8.0, and quantity of the immobilized microorganisms=0.75-1 g/50 mL. The removal rates of TOC, TP, and TN under the above conditions were 80.2%, 81.6%, and 86.8%, respectively., Conclusion: The amount of heterotrophic bacteria in the two lakes was correlated with TOC, TP, and TN. These bacteria could be acclimatized and prepared for the immobilized microorganisms which could effectively remove nitrogen, phosphorus, and mixed organic pollutants in the water sample.

Objective: To study the preparation of seeding type immobilized microorganisms and their degradation characteristics on di-n-butyl phthalate (DBP)., Methods: Diatomite, clinoptilolite, silk zeolite, and coal fly ash were chosen as reserved materials and modified. Their adsorption capacity and intensity in the bacteria were determined and the best carrier was picked out. The seeding type immobilized microorganisms were prepared by the best carrier and then it degraded DBP under different primary concentration, vibration rate, pH, temperature in the presence of metal compounds., Results: The adsorption capacity of the modified coal fly ash, silk zeolite, clinoptilolite and zeolite was 44.2%, 71.6%, 84.0%, and 94.4%, respectively, which was 1.66, 1.49, 1.37, and 1.16 times as high as that of their natural state. Their adsorption intensity was 72.1%, 90.5%, 90.1%, and 91.1% in turn. The modified diatomite was selected to prepare the seeding type immobilized microorganisms. When the primary DBP concentration was 100 to 500 mg/L, the DBP-degraded rate of the immobilized microorganisms could be above 80%. The degradation activity of both the dissociative and immobilized microorganisms was higher in vibration than in stillness. When pH was 6.0 to 9.0, the DBP-degraded rate of the immobilized microorganisms was above 82%, which was higher than the dissociative microorganisms. When the temperature was between 20 degrees C and 40 degrees C, the DBP-degraded rate could reach 84.5% in 24 h. The metal compounds could inhibit the degradation activity of both the dissociative and immobilized microorganisms. The degradation process of the immobilized microorganisms could be described by the first-order model., Conclusion: The adsorption capacity of the diatomite, clinoptilolite, silk zeolite and coal fly ash on DBP-degrading bacteria can be improved obviously after they are modified. The modified diatomite is best in terms of its adsorption capacity and intensity. Its seeding type immobilized microorganisms could degrade DBP effectively and is more adaptable to DBP load, temperature, pH than the dissociative microorganisms. The metal compounds could inhibit the activity of both the immobilized and dissociative microorganisms. The degradation reaction of the immobilized microorganisms on DBP is consistent with the first-order model.

Objective: To study the biodegradation characteristics of seeding type immobilized microorganism on dibutyl phthalate (DBP)., Methods: The immobilized microorganism was made to adsorb DBP degradation dominant bacteria by using modified diatomite as carrier, then it degraded DBP under different primary concentration, vibration rate, pH, temperature and at the presence of metal compounds. The degradation kinetics was analyzed., Results: When DBP primary concentration was 100-500 mg/L, the adsorptive immobilized microorganism could maintain relatively high activity and the DBP degraded rate was above 80% in 24h. Dissociative and immobilized microorganism could get higher degradation activity in vibration than in stillness. When pH was 6.0 - 9.0, the degradation rate of immobilized microorganism on DBP was above 82% in 24h and its activity is higher than dissociative microorganism. In the range of 20 degrees C to 40 degrees C, the DBP degraded rate by immobilized microorganism could reach 84.5% in 24h. If mental compounds existed in the DBP water sample, the degradation activities of dissociative and immobilized microorganism were inhibited obviously. The form of DBP degradation kinetics could be described as the first-order model., Conclusion: The immobilized microorganisms using diatomite as carrier could degrade DBP effectively. The adsorptive immobilized microorganism was more adapted to DBP load, temperature and pH than dissociative microorganism. The mental compounds could inhibited their activities. The degradation reaction of adsorptive immobilized microorganisms on DBP was according with the first-order model.

Objective: Seeking cheap and effective carriers for adsorbing dibutyl phthalate (DBP) degradation dominant bacteria., Methods: Diatomite, clinoptilolite, silk zeolite and coal fly ash were selected as reserve materials and modified. The adsorptive capacity and intensity of each carrier to DBP degradation bacteria were measured., Results: The adsorptive capacity of coal fly ash, clinoptilolite, silk zeolite and diatomite to DBP degradation dominant bacteria was 1.66, 1.37, 1.49 and 1.16 times in turn to that of natural carriers. The comparative tests for each modified carrier indicated that the adsorptive capacity of diatomite, clinoptilolite, silk zeolite and coal fly ash was 94.4%, 84.0%, 71.6% and 44.2% in turn. The adsorptive intensity of above carriers was 91.1%, 90.1%, 90.5% and 72.1%. The degradation rate to 100 mg/L DBP in 24h was 90.2%, 89.9%, 76.3% and 62.4% successively., Conclusion: The adsorptive capacity of diatomite, clinoptilolite, silk zeolite, and coal fly ash to DBP degradation dominant bacteria was enhanced after being modified. The adsorptive capacity and intensity from strong to weak was diatomite, clinoptilolite, silk zeolite, and coal fly ash.