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931.
SEJF多功能水处理器是将物化处理与生化处理有机结合在一起的水处理设备,可在一器内完成均质、曝气、混合、反应和固液分离数种功能.采用SEJF多功能水处理器工艺对印染废水进行处理,工程实践表明,该水处理器工艺具有高效、节能、节地、节资等优点,而且处理效果稳定,运行费用低,操作管理方便,灵活性和适应性强.  相似文献   
932.
焦化废水深度处理试验研究   总被引:1,自引:0,他引:1  
王娟  刘玉学  范迪 《环境工程学报》2009,3(10):1804-1807
采用BC法+复合过滤技术工艺对焦化废水生化出水进行深度处理试验。结果表明,在SE混凝剂投药量为30 mg/L、BC池停留时间为1.5 h、复合过滤器水力负荷为2.4 m3/(m2·h)的条件下,当深度处理进水水质为COD=196.1 mg/L、色度=120倍、NH3-N=35.1 mg/L时,其去除率分别为74.7%、86.7%和69.7%,出水可达回用水要求。  相似文献   
933.
Experiments were conducted on a 4-cylinder direct-injection diesel engine using ultralow sulfur diesel blended with biodiesel and ethanol to investigate the gaseous emissions of the engine under five engine loads at the maximum torque engine speed of 1800 rev min?1. Four biodiesel blended fuels and four ethanol blended fuels with oxygen concentrations of 2%, 4%, 6% and 8% were used. With the increase of oxygen content in the blended fuels, the brake thermal efficiency improves slightly.For the diesel-biodiesel fuels, the brake specific HC and CO emissions decrease while the brake specific NOx and NO2 emissions increase. The emissions of formaldehyde, 1,3-butadiene, toluene, xylene and overall BTX (benzene, toluene, xylene) in general decrease, however, acetaldehyde and benzene emissions increase. For the diesel-ethanol fuels, the brake specific HC and CO emissions increase significantly at low engine load, NOx emission decreases at low engine load but increases at high engine load. The emissions of benzene and BTX vary with engine load and ethanol content. Similar to the biodiesel-diesel fuels, the formaldehyde, 1,3-butadiene, toluene and xylene emissions decrease while the acetaldehyde and NO2 emissions increase. Despite having the same oxygen contents in the blended fuels, there are significant differences in the gaseous emissions between the biodiesel-diesel blends and the ethanol-diesel blends.  相似文献   
934.
温岭市制鞋业产排污系数的核算研究   总被引:1,自引:0,他引:1  
针对温岭市制鞋业原料、工艺、产品基本相同的特点,筛选大、中、小3种规模的制鞋企业进行抽样调查.采用查询历史资料、票据核查、实地勘察和现场监测相结合的办法,收集相关数据,分别用物料衡算法和监测法核算制鞋业的产排污系数.随机选取3家企业对主要污染因子甲苯的产污系数进行验证.应用偏差在-11%~19%.  相似文献   
935.
随着煤炭、石油、天然气等不可再生能源的掠夺式开采的日益严重,中国不可再生能源供需缺口日渐放大,来自于经济增长和消耗强度的冲击使得中国不可再生能源消耗压力逐年增大.在对不可再生能源供需缺口以及消耗构成分析的基础上,运用IPAT方程、LMDI分解法,对中国不可再生能源消耗压力的驱动因素进行实证分析,针对作为主要驱动因素的不可再生能源消耗强度,运用费雪指数分解法进行二次结构、效率效应分解,并就分析结果作出具体剖析.研究结论如下:①中国不可再生能源消耗压力呈现“谷峰交替”型变动趋势,消耗压力的增加主要源于经济因素的驱动,消耗压力的减弱主要源于消耗强度的抑制性驱动作用;②结构效应指数对不可再生能源消耗强度的变动发挥主要影响作用,产业结构的低碳化调整会促进工业部门内部消耗强度的降低,从而达到拉动不可再生能源整体消耗强度降低的目标.  相似文献   
936.
Monitoring campaigns from different locations have recently shown how air concentrations of persistent semivolatile contaminants such as polychlorinated biphenyls (PCBs) often exhibit short-term (less than 24 h) variations. The observed patterns have been ascribed to different factors, such as temperature-mediated air-surface exchange and variability of planetary boundary layer (PBL) height and dynamics. Here, we present a new modeling approach developed in order to investigate the short-term variability in air concentrations of organic pollutants at a local scale. A new dynamic multimedia box model is supplied by a meteorological preprocessor (AERMET) with hourly values of air compartment height and wind speed. The resulting model is tested against an existing dataset of PCB air concentrations measured in Zurich, Switzerland. Results show the importance of such modeling approach in elucidating the short- and long-term behavior of semivolatile contaminants in the air/soil system.  相似文献   
937.

Introduction  

Nanomaterials have widespread applications in several industrial sectors. ZnO nanoparticles (NPs) are among the most commonly used metal oxide NPs in personal care products, coating and paints. However, their potential toxicological impact on the environment is largely unexplored.  相似文献   
938.
Pan B  Tao S  Wu D  Zhang D  Peng H  Xing B 《Chemosphere》2011,84(11):1578-1583
The sorption coefficients obtained in field investigation vary greatly from laboratory sorption experiments. The possible reasons were discussed in literature. Observing the commonly reported desorption hysteresis, this study proposed that the unclear sorption history of the field study could also result in the diverse sorption coefficients. This study conducted a comparative study regarding phenanthrene sorption/desorption behavior in low-concentration multi-time sorption process and the commonly applied high-concentration one-time sorption process. The sorption coefficients determined during the desorption process were much higher than those at sorption process. Thus, the prediction of sorption coefficient should be related with sorption history. Desorption hysteresis was increased with increased equilibration time and decreased solid-phase concentration. In addition, although the apparent contact time between sorbate and sorbent was shorter for low-concentration multi-time sorption, the desorption hysteresis was much stronger, which consequently result in higher sorption coefficients in comparison to high-concentration one-time sorption. Pore swelling or diffusion-controlled sorption kinetics could not explain this phenomenon. This study calls for research attention on sorption history, especially for field investigations.  相似文献   
939.
Cestone A  Di Natale M  De Rosa S 《Chemosphere》2008,71(8):1440-1445
The main objective of this study, within development of engineering solutions for coastal areas depuration, was to establish the role of the benthic macro-organisms in the biodegradation of the detergents in marine environment and to estimate the toxicity of these substances for a particular marine species: the ascidian Styela plicata. The experimental studies undertaken in aquarium with seawater enriched in a pure lynear alkylbenzene sulfonate (LAS), the 1-(p-sulfophenyl)nonane (1C9-LAS), showed that the degradation was two times more fast in presence of the S. plicata, than of the only marine bacteria. The toxicity of this pollutant was also determined. This study demonstrates that the ascidia S. plicata can be a potential biomediator for the surfactant 1C9-LAS, and it can be used to design a pilot project, to bioremediate harbours and the coastal areas interested from the urban pollution.  相似文献   
940.
ABSTRACT

Abandoned industrial sites and mines may constitute possible hazards for surrounding environment due to the presence of toxic compounds that may contaminate soils and waters. The possibility to remove metal contaminants, specifically nickel (Ni), by means of fungi was presented exploiting a set of fungal strains isolated from a Ligurian dismissed mine. The achieved results demonstrate the high Ni(II) tolerance, up to 500 mg Ni l?1, and removal capability of a Trichoderma harzianum strain. This latter hyperaccumulates up to 11,000 mg Ni kg?1, suggesting its possible use in a bioremediation protocol able to provide a sustainable reclamation of broad contaminated areas.  相似文献   
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