[Combined Process of DNBF-O3-GAC for Nitrogen and Phosphorus and Metabolite Advanced Removal].

To improve the quality of the tailings water from a wastewater treatment plant (WWTP), a denitrification biofilter (DNBF) with a composite filler composed of a new slow-release organic-carbon source (SOC-F), sponge iron, and activated carbon was tested. Studies were conducted in the combined process of DNBF-O3-GAC to explore the efficiency of the advanced removal of nitrogen, phosphorus, and microbial metabolite by using synthetic effluent made from running water and chemicals. Corresponding comparative studies were conducted by using the secondary effluent from the WWTP. The microbial population structure in the biofilm of the denitrification biofilter was analyzed by adopting MiSeq high-throughput sequencing technologies. The results indicated that the combination process achieved high efficiency removal of nitrogen, phosphorus, and microbial metabolite. The average removal rate of NO3--N in the simulated and actual water period reached 88.87% and 79.99%, respectively; the average removal rate of TP reached 87.67% and 65.51%, respectively; and the average removal rate of UV254 reached 45.51% and 49.23%, respectively. Each processing unit had different functions. The changes in NO3--N, TN, TP, and TFe mainly occurred in the denitrification biofilter, and the removal of UV254 and the change in the three-dimensional fluorescence intensity mainly occurred in the ozone-activated carbon reactor. The cluster analysis at the genus level indicated that the denitrification system had sulfur autotrophic denitrifying bacteria and heterotrophic denitrifying bacteria. Sulfur autotrophic denitrification increased obviously in the actual water period when relatively lack of carbon sources, and the proportion of Thiobacillus increased from 7.44% to 29.62%. The complementary effect of sulfur autotrophic denitrification and heterotrophic denitrification had extended the use of the new slow-release carbon source.

[Preparation and Phosphorus Removal Mechanism of Highly Efficient Phosphorus Adsorbent Mg/Al-LDO].

Aiming at the problem of phosphorus removal in water, Mg/Al-layered double hydroxides (Mg/Al-LDHs) were synthesized via optimized constant pH co-precipitation method, and highly efficient phosphorus adsorbent Mg/Al-layered double oxide(Mg/Al-LDO) was obtained when it was calcined at high temperature. Based on the adsorption characteristics of phosphorus removal, the study combined Zeta potential, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) to analyze the changes of isoelectric point, crystal structure and functional group before and after adsorption. In addition, Mg/Al-LDO of phosphorus adsorption mechanism was discussed. The results indicated that using the optimized co-precipitation method in the conditions of Mg/Al=2:1, calcination temperature 450℃, and calcination time 2 h, the Mg/Al-LDO adsorption capacity of phosphate was the best, and the maximum adsorption capacity could reach 176.94 mg·g-1, which was basically consistent with the theoretical adsorption capacity of 191.57 mg·g-1, far higher than those of Mg/Al-LDHs and other phosphorus adsorbents. The results showed that the experimental data has the best fitting result with pseudo-second-order kinetics model. The adsorption process was consistent with Langmuir adsorption isotherm model. The results of Zeta potential, XRD and FTIR showed that phosphorus adsorption of Mg/Al-LDO was accomplished co-operatively by electrostatic attraction, anion in layer, ions exchange, and surface co-ordination.

[Feasibility of 3BER-S Process for the Deep Denitrification in Synch with the Removal of PAEs from Reclaimed Water].

In order to investigate the feasibility of deep denitrification and simultaneous removing phthalate esters (PAEs) in the process of reclaimed water treatment uses three-dimensional biofilm-electrode reactor coupled with sulfur autotrophic deep denitrification technology (3BER-S), the technological characteristics and mechanisms were analyzed based on determining the static adsorption capacity of biofilm cultured active carbon fillers in 3BER-S reactor together with the operation results of dynamic denitrification and simultaneous PAEs removing. The results showed that the average adsorption rates of DBP, DEHP were 85.84% and 97.12% in the biofilm cultured active carbon fillers, the equilibrium adsorption capacities were 0.1426 mg x g(-1) and 0.162 mg(-1) and the time spans of reaching adsorption saturation were 120 min and 60 min, respectively; The existence of PAEs had no obvious effect on denitrification, the reactor effluent concentration of TN was in range of 1-2 mg x L(-1) before and after the addition of PAEs, and the average removal rate of TN reached above 94%; 3BER-S denitrification system showed significant ability in removing PAEs, leading to effluent concentrations of DBP and DEHP of no more than 6 microg x L(-1) with removal rates of above 96%; this was due to the synergistic effect of absorption, biodegradation and electrochemistry. After treatment with 3BER-S technology, DBP and DEHP in simulative municipal secondary effluent met the regulated limitation of The Reuse of Urban Recycling Water Quality Standard for Groundwater Recharge (GB/T 19772-2005).

Activity Study on Antibacterial Protein Isolated From Musca domestica During Larvae-pupae Metamorphosis / 中国生物工程杂志

Objective: To research the activity of antibacterial proteins isolated from Musca domestica during larvae-pupae metamorphosis. Methods: The 5-day-old larvae of Musca domestica were injured with a needle. 24h later, the larvae which had changed into pupae were selected. The antibacterial protein was isolated by a four-step protocol including grinding, heating, CM-sepharose F. F. cationexchange chromatography and another CM-sepharose F. F. chromatography. Antibacterial activities of samples were tested by an ultrasensitive radial diffusion assay using Staphylococcus aureus as the indicator organism. The molecular weight of the isolated protein was determined by SDS-PAGE.Results: The molecular weight of this isolated protein was 43kDa, and its antibacterial activity was strong. Conclusions: A kind of protein with strong antibacterial activity can be produced in the Musca domestica during larvae-pupae metamorphosis.

Activity Study on Antibacterial Protein Isolated From Musca domestica During Larvae-pupae Metamorphosis / 中国生物工程杂志

Objective: To research the activity of antibacterial proteins isolated from Musca domestica during larvae-pupae metamorphosis. Methods: The 5-day-old larvae of Musca domestica were injured with a needle. 24h later, the larvae which had changed into pupae were selected. The antibacterial protein was isolated by a four-step protocol including grinding, heating, CM-sepharose F. F. cationexchange chromatography and another CM-sepharose F. F. chromatography. Antibacterial activities of samples were tested by an ultrasensitive radial diffusion assay using Staphylococcus aureus as the indicator organism. The molecular weight of the isolated protein was determined by SDS-PAGE.Results: The molecular weight of this isolated protein was 43kDa, and its antibacterial activity was strong. Conclusions: A kind of protein with strong antibacterial activity can be produced in the Musca domestica during larvae-pupae metamorphosis.