[TTC-ETS activity monitoring of A2/O process for combined sewage treatment].

The influences of variations of temperature and F/M on the TTC-ETS activity have been experimentally studied. The correlation between TTC-ETS activity and COD degradation was also analyzed. Comparing TTC-ETS activities with physical and chemical indexes when high C/N ratio impacted A2/O process, the advantages and disadvantages of using TTC-ETS activity to characterize the status of A2/O process were illustrated. The results showed that both temperature and F/M were positively correlated with TTC-ETS activity. TC-ETS activity was in the range of 13.2-48.3 mg/(g x h) and the maximum value was 60 mg/(g x h) which had a significant relationship with COD removal rate. In this system, abnormal state was pre-warned by TTC-ETS activity. The highest removal rate of COD appeared when TTC-ETS activity was 41.0 mg/(g x h).

[Evaluation of the damaging effect of dyestuff on Phanerochaete chrysosporium with amplified fragment length polymorphism (AFLP) analysis].

The AFLP analysis was carried out in order to evaluate the DNA damaging effects of dyestuff of different concentrations on Phanerochaete chrysosporium. The DNA similarity and UPGMA cluster analysis were conducted to determine the relationships between the concentrations of dyestuff and DNA damaging effects. The results showed that the AFLP analysis could reflect the polymorphisms of DNA well, and the primer pairs E-AAC/M-CAA could give more amplified DNA fragments than others primers. From the DNA maps of best primer pairs, 35 clear and stable DNA bands were observed, including 12 polymorphous bands which were accounted for 34.3% diversity. It was indicated from the DNA similarity and UPGMA cluster analysis that DNA polymorphisms correlated with dyestuffs concentrations well. If the concentration of dyestuff was not higher than 50 mg/L, the damaging effect on DNA was finite. If the concentrations of dyestuff were up to 300 mg/L, the DNA of Phanerochaete chrysosporium would have been injured greatly, and would have been bankrupted in its intrinsic function.

[Relation analysis of phosphorus removal and BOD5 loading using PHB monitoring in A2/O process].

In a pilot-scale anaerobic-anoxic-oxic experimental system for municipal wastewater treatment, PHB consumption in an oxic tank and PHB production in an anaerobic tank had been monitored overtime, and relations among PHB consumption/production, phosphorus removal/release and BOD5 loading had been analyzed. The results indicated that the consumption of PHB was positively related with phosphorus removal, and about 140 mg PHB consumption could result in 1 mg P removal. In the anaerobic tank, about 1.17 mg P release could result in 100 mg PHB production. The PHB production at the loading of 0.176 g/(g x d) was 4 mg/g MLSS less than that at 0.413 g/(g x d). No significant relevance was observed between PHB and BOD5 removal. The PHB of microorganism synthesizes was increased with the increase of temperature. Compared with the lowest temperature (17.1 degrees C), 20% of the total PHB content was increased at the maximum temperature (33.2 degrees C) in active sludge.

[Experimental study on the processes and mechanism of enhanced denitrification by addition zeolite in wastewater treatment].

Aim to enhance nitrogen removal from wastewater, addition zeolite to aeration tank was preformed. The result showed that addition of zeolite could improve the nitrification/denitrification efficiencies by comparing two phase experiment of 25 mg/L with blank and 25 mg/L with 50 mg/L, and the population of nitrifying bacteria in activated sludge increased obviously. When 25 mg/L zeolite was added into aeration tank, NH4(+) -N and TN removal increased 10% - 13% and 13% respectively, endogenous respiration rate of nitrification increased about 138%, and the population of nitrification bacteria increased about 2.2 folds. But the nitrogen removal and endogenous respiration rate of 50 mg/L enhanced indistinct comparing with 25 mg/L. These results indicated that NH4+ ion-exchange and accumulation to the interior/outer surfaces of zeolite, co-existence of aerobic and anoxic micro-environments were responsible for the enhanced denitrifying function.