Advanced Materials Research Vols. 610-613

Abstract: In recent years, continuous input of exogenous pollutants has changed the original environment of riparian zone, impacting on soil biological community and the stability of ecosystem at the riparian zone. Therefore, it is necessary to study these impacts for environmental protection and providing scientific basis for environmental decision-makers. In this paper, the author took the microbial community of riparian zone as an example and reviewed the relevant literatures at home and abroad published latest years. The impacts of exogenous contamination on microbial community succession in riparian zone were been discussed, and microbial species, microbial biomass and community information were been revealed for understanding the impact of continuous input of exogenous pollutants on micro-ecosystem structure and function and the degree and finding out the leading pollutants in riparian zone. The paper has a great significance to the development of microbial resources and protection of riparian zone.

Abstract: The limestone-lime washing technology is the most widely used WFGD process, which normally we adopt to control the discharge of SO2 caused by coal’s combustion. Through the research on the oxidation kinetics of sulfite in this paper, it is indicated that macroscopic chemical reaction which responses to rate of sulfite is 1/2. And the results of orthogonal test can be concluded that: to the extent influence of oxidization reaction rate, the influences of temperature is the most significant, and influences of stirred speed is nearly negligible. The optimized operation factors may be shown as that temperature is controlled at 40°C, air ventilation is at 88ml/min,pH is 4.5 and stir speed is 500 r/min.

Abstract: In order to study the pollution characteristics of Pb in soil and plant of Zhaoyuan City, the surface soil and green plant samples were collected in the downtown of Zhaoyuan City. The Pb content was determined with the flame atomic spectrophotometer. The results showed that the range of the Pb content in soil was 53.23～291.14 mg/kg, with the average content being 96.59 mg/kg. There was a serious Pb contamination in the downtown surface soil in the investigative region. The content of Pb was different in different functional areas, and the industrial area had the most Pb contamination with its content reaching 132.99 mg/kg. The range of the Pb content in leaves of the plant samples was from 5.79～36.6 mg/kg, with that in stems being 13.5～57.17 mg/kg and that in branches being 4.85～54.68 mg/kg. The content in plants and soil had no significant correlation.

Abstract: A new method was developed for the speciation of inorganic arsenic in coal samples by liquid chromatography coupled to hydride generation atomic fluorescence spectrometry after microwave-assisted extraction. Effective extract of As(III), As(V) in coal sample was achieved by 1.0molL-1 H3PO4 and 0.1 molL-1ascorbic acid. Under the optimized conditions, the limits of detection were 0.01 ugL-1and 0.02 ugL-1for As(III), As(V). The relative standard deviation were 2.4 %, 3.3 % (c= 20.0 gL-1, n=7). The proposed method was successfully applied for the determination of speciation of inorganic arsenic in coal samples and GBW11117.

Abstract: In this paper, the experimental data of CO, CO₂ and total volatile organic compound (TVOC) concentration in a residential kitchen are presented. Based on them, a simulation software with friendly and simply operating interfaceis is developed on the platform of VC++. The distribution law of the contaminants is studied via the simulation results, and it is obvious that location of accumulation of the contaminants are highly relevant to the location of stove and closer to the walls. An addition natural air makeup system is proposed to improve indoor airenvironment in kitchens, the effection of the air makeup system is analyzed with exergy theory.

Abstract: The uncertainty of operating parameters hinders the practical application of the biological desulfurization. To solve this problem, this study which was conducted in room temperature, pH around seven conditions, investigated the effects of the operating parameters on the hydrogen sulfide (H2S) removal performance in the biotrickling filter, including inlet H2S concentration, inlet flow rate or gas retention time, inlet volume load and circulating liquid spraying flux. The results showed that, the inlet H₂S concentration should be controlled within 800mg/m3, 650mg/m3, 400mg/m3, 300mg/m3 respectively while the inlet flow rate was 150L/h, 200L/h, 250L/h, 300L/h, at those conditions, the outlet H₂S concentrations were lower than 8mg/m3 and the H2S removal efficiencies were more than 98%. The optimum gas retention time was 12.37s, corresponding to the inlet flow rate of 200L/h, at this time, even if the inlet H2S concentration as high as 700mg/m3, the removal efficiency could be still more than 98%, the outlet concentration of H2S was only 13.1mg/m3. The maximum inlet volume load was 130g/(m3•h), in this condition, the outlet concentration of H2S could be controlled below 12mg/m3, the removal efficiency could above 98.4%.

Abstract: Full scale two-stage activated sludge process (ASP) with fixed biological media was used to treat coal gasification wastewater. The ASP has operated for more than one year and COD, total phenol and NH4-N removal effects were illuminated. COD and total phenol removal rates were around 85% and 90% during long term operation. Effluent COD and total phenol of the first stage of the ASP had an abnormal increase and turned to normal after several weeks. Nitrification of the ASP increased slowly and NH4-N removal rates achieved 80% after 15 weeks. Stenotrophomonas maltophilia K279a is isolated from coal chemical industry wastewater. The optimum conditions for PO production are phenol 1000mg/L, temperature 30-34 and pH 7-7.5. The strain resists 980mg/L COD and 805mg/L phenols. The degradation rate of phenols reaches 97% in 48h. The results show that Stenotrophomonas maltophilia K279a can be applied to the aerobic process with high proportion of phenols

Abstract: A SBR was used to treat power plant sewage based on SND when pH, DO(dissolved oxygen),MLSS, were 7.0-8.0, 0.5-1mg/L, 3000±200mg/L, respectively. Results indicated average removal efficiency of COD and NH₄⁺-N were 89% ,96.34%.Because of low COD/ NH₄⁺-N, average removal efficiency of TN(total nitrogen)was only 71.15%, effect of SND was not apparent. After improving COD/ NH₄⁺-N by adding carbon source intermittently, removal effects of COD and NH₄⁺-N were not reduced, and effluent NO₃^--N and NO₂^--N was not accumulated, average removal efficiency of TN was 95%, and efficiency of SND was enhanced obviously. The effluent of system was recycled effectively. It indicates that SBR based on SND is feasible in theory and technology which is applied to treat power plant sewage.

Abstract: The degradation of aqueous safranine T (ST) solution using direct current (DC) glow discharge plasma (GDP) at atmospheric pressure air was investigated. Several factors including pH, the gas gap between the anode tip and the solution surface, the anode needle sealed into the glass, which might impact the ST degradation process, were examined, respectively. Both the degradation rate of ST and the energy utilization efficiency were used as characteristic quantities to evaluate the degradation effect in our work. The results suggest that the highest degradation rate is 94.26% after 16 min treatment and the highest average energy utilization efficiency reaches 5.28 g/kWh in the 12 min treatment, the most suitable gas gap height and pH are 5 mm and 4.60, respectively. Meanwhile, the needle sealed with the glass facilitates the ST degradation process.

Abstract: In this study, modified activated carbon used as catalysts treat imidacloprid pesticide wastewater with microwave-assisted catalytic oxidation. The effect of working conditions such as hydrogen peroxide concentration, homogeneous catalysts concentration of Fe2+, amount of activated carbon catalysts, microwave power, irradiation time, wastewater temperature, and pH value on the treatment of imidacloprid pesticide wastewater in the process was investigated. The results show that COD removal rate , can reach 89.25%, with the following working conditions : imidacloprid pesticide wastewater with initial concentration of 268mg/ L , 100 mL ; hydrogen peroxide solution added at a concentration of 26.52g/L , Fe2+ concentration ,109.81mg/L; amount of activated carbon catalysts, 5g;power of microwave , 119 W; irradiation time , 4min ; pH value , 6.