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991.
马蔷  王奎升  李秀金  朱保宁 《环境工程》2013,31(3):110-112,138
针对城市生活垃圾研制了一种用于好氧发酵的滚筒式生物反应器。滚筒式生物反应器的设计主要包括主体结构设计,支承装置的设计计算,传动装置的功率选用,进、出料装置的功能研究等。为保证滚筒式反应器发挥最大功用,在滚筒内壁增设抄板并设计了抄板的结构形式、布置情况及安装位置,用以延长生活垃圾在滚筒内的停留时间,使好氧发酵更为充分。  相似文献   
992.
王建强 《环境工程》2013,(Z1):440-443
马迹山港区近邻嵊泗风景区,存在着多处环境敏感点,对环境保护要求较高。防尘治理严格执行"以新带老"的环保设计原则,采用了一些看似"常规"但又"关键"的技术措施。监测数据表明:控制粉尘污染的措施具有很强的针对性.效果显著,可为钢铁、火电企业在矿石与煤炭输送、转运领域提供参考。  相似文献   
993.
王刚 《环境工程》2013,(Z1):530-533,593
随着污泥产生量的日益增加,其对生态环境造成的负面影响逐渐引起了世界的关注,同时人类社会也在共同探寻一个经济合理、安全可靠的污泥处置方案。系统分析了国内外污泥处理处置技术现状、主流技术研究及应用进展,并结合我国国情对污泥处理处置发展趋势进行了展望。  相似文献   
994.
从化学热力学角度和沉淀转化角度,理论上分析了碳酸钠、氢氧化钠分别与硫酸钙发生化学反应的可能性和反应进行的限度。并结合动力学规律,提出影响化学反应的条件,通过实验进行检验。最后提出,在实际工作中,达到良好清洗目的可采取的措施。  相似文献   
995.
王宁  竹涛  陈莎 《环境工程》2013,(Z1):666-670
介绍了煤矿甲烷宏观涌出量的估算方法,选择使用原煤产量法,以煤矿甲烷的相对涌出量为基础,建立了"产量-涌出量函数模型",得到三种不同类型矿井煤矿甲烷的分类涌出系数。  相似文献   
996.
Metal(Cu,Co,or Zn) loaded ZSM-5 and Y zeolite adsorbents were prepared for the adsorption of hydrogen cyanide(HCN) toxic gas.The results showed that the HCN breakthrough capacity was enhanced significantly when zeolites were loaded with Cu.The physical and chemical properties of the adsorbents that influence the HCN adsorption capacity were analyzed.The maximal HCN breakthrough capacities were about the same for both zeolites at 2.2 mol of HCN/mol of Cu.The Cu2p XPS spectra showed that the possible species present were Cu2O and CuO.The N1s XPS data and FT-IR spectra indicated that CNwould be formed in the presence of Cu+/Cu2+ and oxygen gas,and the reaction product could be adsorbed onto Cu/ZSM-5 zeolite more easily than HCN.  相似文献   
997.
Bamboo charcoal(BC) was used as starting material to prepare iron-modified bamboo charcoal(Fe-MBC) by its impregnation in FeCl 3 and HNO 3 solutions simultaneously,followed by microwave heating.The material can be used as an adsorbent for Pb(Ⅱ) contaminants removal in water.The composites were prepared with Fe molar concentration of 0.5,1.0 and 2.0 mol/L and characterized by means of N 2 adsorption-desorption isotherms,X-ray diffraction spectroscopy(XRD),scanning electron microscopy coupled with energy dispersive X-ray spectrometry(SEM-EDS),Fourier transform infrared(FT-IR) and point of zero charge(pH pzc) measurements.Nitrogen adsorption analyses showed that the BET specific surface area and total pore volume increased with iron impregnation.The adsorbent with Fe molar concentration of 2 mol/L(2Fe-MBC) exhibited the highest surface area and produced the best pore structure.The Pb(Ⅱ) adsorption process of 2Fe-MBC and BC were evaluated in batch experiments and 2Fe-MBC showed an excellent adsorption capability for removal Pb(Ⅱ).The adsorption of Pb(Ⅱ) strongly depended on solution pH,with maximum values at pH 5.0.The ionic strength had a significant effect on the adsorption at pH < 6.0.The adsorption isotherms followed the Langmuir isotherm model well,and the maximum adsorption capacity for Pb(Ⅱ) was 200.38 mg/g for 2Fe-MBC.The adsorption processes were well fitted by a pseudo second-order kinetic model.Thermodynamic parameters showed that the adsorption of Pb(Ⅱ) onto Fe-MBC was feasible,spontaneous,and exothermic under the studied conditions,and the ion exchange mechanism played an significant role.These results have important implications for the design of low-cost and effective adsorbents in the removal of Pb(Ⅱ) from wastewater.  相似文献   
998.
Rheological tests for raw and conditioned activated sludge(AS) or anaerobic digested sludge(ADS) show that power-law relationships can be used to describe the evolution of several rheological parameters,i.e.,limiting viscosity(η∞),yield stress(τy),cohesion energy of the sludge network(Ec),and storage modulus(G’),with total suspended solid(TSS) content in raw and conditioned sludge.A gel-like structure that behaves similar to weak-link flocs/aggregates was observed in AS and ADS.As derived from the double-logarithmic plots of G’-TSS content,the mass fractal dimensions of the raw and conditioned AS or ADS flocs/aggregates were 2.70 and 2.53 or 2.85 and 2.79,respectively.The rheological tests also indicate that both polymer conditioning and increased TSS content led to improved elastic behavior,cohesion energy,and yield stress of the sludge network,as well as expanded the corresponding linear viscoelastic range.The porosity of AS or ADS flocs/aggregates will be improved by polymer conditioning.  相似文献   
999.
We used aerated systems to assess the influence of the bacterioplankton community on cyanobacterial blooms in algae/post-bloom of Lake Taihu, China. Bacterioplankton community diversity was evaluated by polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE) fingerprinting. Chemical analysis and nitrogen dynamic changes illustrated that NH4+-N was nitrified to NO2-N and NO3-N by bacterioplankton. Finally, NH4+-N was exhausted and NO3-N was denitrified to NO2-N, while the accumulation of NO2-N indicated that bacterioplankton with completely aerobic denitrification ability were lacking in the water samples collected from Lake Taihu. We suggested that adding completely aerobic denitrification bacteria(to denitrify NO2-N to N2)would improve the water quality. PCR-DGGE and sequencing results showed that more than 1/3 of the bacterial species were associated with the removal of nitrogen, and Acidovorax temperans was the dominant one. PCR-DGGE, variation of nitrogen, removal efciencies of chlorophyll-a and canonical correspondence analysis indicated that the bacterioplankton significantly influenced the physiological and biochemical changes of cyanobacteria. Additionally, the unweighted pair-group method with arithmetic means revealed there was no obvious harm to the microecosystem from aeration. The present study demonstrated that bacterioplankton can play crucial roles in aerated ecosystems, which could control the impact of cyanobacterial blooms in eutrophicated fresh water systems.  相似文献   
1000.
Fe203 particle catalysts were experimentally studied in the low temperature selective catalytic reduction (SCR) of NO with NH3. The effects of reaction temperature, oxygen concentration, [NH3]/[NO] molar ratio and residence time on SCR activity were studied. It was found that Fe203 catalysts had high activity for the SCR of NO with NH3 in a broad temperature range of 150-270℃, and more than 95% NO conversion was obtained at 180℃ when the molar ratio [NH3]/[NO] = 1, the residence time was 0.48 seconds and 02 volume fraction was 3%. In addition, the effect of SO2 on SCR catalytic activity was also investigated at the temperature of 180℃. The results showed that deactivation of the Fe2O3 particles occurred due to the presence of SO2 and the NO conversion decreased from 99.2% to 58% in 240 min, since SO2 gradually decreased the catalytic activity of the catalysts. In addition, X-ray diffraction, Thermogravimetric analysis and Fourier transform infrared spectroscopy were used to characterize the fresh and deactivated Fe2O3 catalysts. The results showed that the deactivation caused by SO2 was due to the formation of metal sulfates and ammonium sulfates on the catalyst surface during the de-NO reaction, which could cause pore plugging and result in suppression of the catalytic activity.  相似文献   
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