Advanced Materials Research Vols. 955-959

Abstract: Using phytoremediation technique to remove contaminants from soil had become a topic in current research.This article expounded the domestic and oversea research progress of hyperaccumulators on cultivation techniques and was systematically elaborated from many aspects,including variety selecting,seedling breeding,fertilizing (nitrogen phosphorus and organic fertilizer),usage of chelator and ameliorant,polyploid breeding,etc.The direction of hyperaccumulators research is put forward that the aboveground biomass and the heavy metal accumulation quantity should be raised through improving cultivation measures,meanwhile a new idea about research of plant tissue culture has been come up with.

Abstract: When the reactor is added with ectoine of concentrations of 0, 0.1, 1 and 10 mmol/L, the impacts on brine waste treatment efficiency are investigated. The results show that the outflow COD and ammonia nitrogen removal rates are the highest, when the ectoine concentration is 0.1 mmol/L. The brine waste treatment efficiency under addition of ectoine of 1 and 10 mmol/L is even worse than that without ectoine addition. It can be preliminarily determined that the best ectoine dosage is in between 0.1-1.0 mmol/L. When ectoine concentrations added in reactors are 0.2, 0.5, 0.8 and 1.0 mmol/L, the results show that the average reactor outflow COD and ammonia nitrogen removal rates are increased compared with those of reactor without adding ectoine. But when ectoine of 1.0 mmol/L is added, the outflow COD and ammonia nitrogen removal rates decrease. When ectoine dosage is 0.5 mmol/L, the reactor outflow COD and ammonia nitrogen values are the lowest, the removal rates are the highest, the average COD removal rate is 74.46%, and the average ammonium nitrogen removal rate is 54.97%. Compared with reactor without adding ectoine, COD and ammonium nitrogen removal rates are increased by 13.16% and 26.81%. Therefore, the best dosage of ectoine is 0.5 mmol/L.

Abstract: Compared to other desulfurization technologies, aerodynamic emulsification technology has obvious advantages among the whole flue gas desulfurization technologies. This paper describes the characteristics of aerodynamic emulsification technology from the perspectives of the technical and economic, and affirms its development and application in the recycling lead industry with examples, while denying use desulfurization equipment of Italy in China.

Abstract: Lake water is used as the raw water. The water carries the following characteristics: high organic content in individual sessions, high-algae and odor in summer. At present, the conventional treatment process is unable to cope with. The application of microfiltration system in the pilot test is studied. Filter effluent and air flotation effluent are used as the microfiltration influent. Membrane flux are 80L/m²/h, 90L/m²/h, 100L/m²/h.Water quality is stable. The average turbidity is 0.1NTU. Total coliform and total bacteria in effluent are not detected. The recovery of water is greater than 96.1%.Potassium permanganate preoxidation + powder carbon dosing + conventional treatment + microfiltration membrane system can effectively solve organics, high algae and odor problems. It also can improve the coping capacity to respond mutation of the water quality.

Abstract: The MOSA (Modified-Oxic-Settling-Anaerobic) system was developed to reduce the impact of OSA process on the aerobic reactor and enhance the effect of anaerobic reactor by changing the style of sludge and supernatant interchange on OSA process. As revealed in this research, the MOSA system could generate 11.8 % less sludge compared with conventional OSA system, while effluent was almost the same on COD、SS、NH₄-N,NO₃-N、TN、TP and cations. But the cumulative TN and NH₄-N of sludge in the two systems had shown a certain increase. The MOSA provided a good method to optimize the operating of OSA process, and gain a more sludge reduction.

Abstract: A pH-stat stirred-tank scrubber for capturing carbon dioxide using aqueous ammonia was used to explore the effects of process variables on the absorption of carbon dioxide. In order to maintain the pH value of the solution, aqueous ammonia was automatically introduced into the tank through the action of a pH-controller. The process variables were the pH of the solution, gas-flow rate, gas concentration and stirring speed. The absorption rate and mass-transfer coefficient could be determined by means of mass balance at a steady-state. It was found that the liquid-flow rate was 0.50-58.33 ml/min; the removal efficiency was in the range of 30.1-100% and the loading of CO₂ was in the range of 0.02425-0.5661 mol-CO₂/mol-NH₃. The results also showed that the absorption rate was in the range of 5.14x10^-5 to 6.27x10^-4 mol/s-L, while the mass-transfer coefficient was in the range of 0.015 to 0.14 1/s. The effects of mixing on the absorption rate, mass-transfer coefficient and loading of CO₂ were also discussed in this work.

Abstract: As the human activities increasing, pesticide, oil and heavy metal used widely caused the environmental pollution more and more serious. Therefore, it is very necessary to find the reasonable and efficient method to degrade environmental pollutants. This article summarized the construction of genetic engineering bacteria and its applications in pesticide pollution, oil pollution and heavy metal pollution bioremediation, which has proved to be a hot pot in environmental pollutants bioremediation researching. It also put forward the difficulties in the construction and application of genetic engineering bacteria and developing trend.

Abstract: Suspended carriers were added into a submerged membrane bioreactor (SMBR) using polypropylene non-woven fabric (PP NWF) as membrane model to treat synthetic wastewater. The changes of EPS_SEPS_B and EPS in activated sludge mixing liquid of MBR and in sludge on membrane model surface were researched at different aeration rate. The results showed that adding suspended carriers in MBR can increase the concentration of EPS_S and EPS_B in activated sludge mixing liquid, but the effect on EPS_S and EPS_B in the sludge on membrane model surface is related to aeration rate. Adding suspended carriers can increase the concentration of EPS_S and EPS_B in the sludge on membrane model surface at 0.10m³/h of aeration rate; the concentration of EPS_S and EPS_B in the sludge with suspended carriers is reduced when aeration rate is increased to 0.25m³/h. The study on the effect of aeration rate on EPS in sludge mixing liquid of MBR and in sludge on membrane model surface showed that an optimized aeration rate exists if suspended carriers are added to control MBR membrane fouling. At the optimized aeration rate, membrane fouling can be mitigated and controled effectively.

Abstract: Poly-phosphate accumulating organisms (PAOs) could use nitrite as electron acceptor but poorly function compared to oxygen in phosphorus removal. The authors try to figure out the different effects on anoxic and aerobic P-uptake by environmental factors (pH, temperature and nitrite concentration) and identify the real inhibitor in anoxic metabolisms. 26 sets of batch tests were designed, using highly concentrated PAO cultures. The results show pH influence on P-uptake activity are similar in anoxic and aerobic tests, but temperature has strong effects on aerobic P-uptake activity compared to anoxic. pH values were are correlated linearly with nitrite reduction and P-uptake rates instead of FNA. Also, weak correlation between FNA and two reaction rates shows pH rather than FNA is likely the main inhibitor. P-uptake rates are correlated linearly with nitrite reduction and PHA consumption rates. It’s possible that intracellar concentration isn’t affected by FNA diffusion and don’t affect intracellar P-uptake process.

Abstract: From the present situation of legislation on utilization of domestic sea water, this article reveals the contradictions between the shortage of water resources and legislation gaps, explore the necessity and feasibility of build up a framework for legislation on utilization of domestic sea water, which aspect is to promote the healthy development of domestic seawater industry.