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871.
针对人类社会在日常运转中产生的大量餐厨垃圾,当下最有效的应对措施是发展相关的餐厨垃圾处理产业,以相关的工作模式和工作设备来应对餐厨垃圾的处理工作。由于餐厨垃圾的特殊性,不同于一般的日常生活垃圾,因此餐厨垃圾的处理设备自然也就有独特的特点与性质。当下社会中餐厨垃圾处理设备行业的发展可谓如火如荼,各种各样的餐厨垃圾处理设备应运而生,针对餐厨垃圾处理设备的发展现状与发展趋势详细的探讨,对促进中国餐饮垃圾处理行业的发展具有借鉴意义。 相似文献
872.
结合案例分析交通噪声对临路高层建筑声环境的影响,随着楼层的变化,噪声贡献值呈现抛物线型变化。在第3层~第5层处噪声值达到最大,然后随着楼层增加噪声值逐渐减小;此外低楼层处夜间噪声超标严重。在隔声设计时应重视噪声最大值出现的位置及夜间时段的噪声影响,增加声屏障的高度对提高低楼层隔声效果有较明显作用。对于临路高层建筑,单一的声屏障措施的降噪效果有限且有众多限制因素,采取声屏障+隔声窗措施有较好的降噪效果。 相似文献
873.
U. Pinto 《中国人口.资源与环境(英文版)》2015,13(3):250-264
The demand for potable water is rising rapidly due to an ever-increasing population, economic activities, and dwindling water supplies. To provide adequate water supplies in the future, understanding the issues and challenges in the reuse of water and developing appropriate strategies for reuse will be critical. One way to augment water supplies for residential use is to reuse graywater – the wastewater from kitchens, bathrooms, and laundries. In this article, we critically review the evolution of water reuse, the definition of graywater, graywater reuse practices, volumes and flow in different situations, and graywater characteristics. We then examine the issues associated with different graywater treatment methods and how using graywater for irrigation around homes affects soil quality and plant growth. The study concludes that graywater treatment costs, human health risks, and its effect on soil quality are some of the challenges that need to be addressed in the future for widespread and sustainable reuse of graywater for irrigation around homes. 相似文献
874.
875.
Effects of gas flow rate, inlet concentration and temperature on the biofiltration of toluene vapors 总被引:2,自引:0,他引:2
Vergara-Fernández A Lara Molina L Pulido NA Aroca G 《Journal of environmental management》2007,84(2):115-122
In this work the variation in the elimination capacity of a biofilter as a function of the gas flow and toluene concentration was studied. A bioreactor 0.75 m high x 14.5 cm diameter was used, divided into three equal stages, using compost to support the microorganisms, and sea shells to control the pH. The biofiltration of toluene was evaluated for flows between 0.12 and 0.73 m(3)h(-1) in a concentration range of 1-3.2 gm(-3). It was observed that on increasing the toluene inlet load by 90% (from 37 to 70 gm(3)h(-1)), the conversion by the biofilter varied by only 5% (from 98% to 93%). The biofiltration system used achieved elimination capacities of up to 82 gm(-3)h(-1) for a toluene load of 100 gm(-3)h(-1). 相似文献
876.
Because the large rivers of the Seine watershed have a low microbiological water quality, the main sources of fecal contamination were investigated in the present study. The inputs of the point (wastewater treatment plants (WWTPs) effluents) and non-point sources (surface runoff and soil leaching) of fecal bacteria were quantified for Escherichia coli and intestinal enteroccoci used as bacterial indicators. In order to assess the contamination through non-point sources, fecal indicators abundance was estimated in samples collected in small streams located in rural areas upstream from all point sources; these small rivers were characterized by the land use of their watershed. Bacterial indicator numbers were also measured in effluents of WWTPs, some using classical treatment (settling followed by activated sludge process) and some using an additional disinfection stage (UV irradiation). These data were used to estimate the respective importance of each type of source at the scale of the whole Seine river watershed taking into account the land use and the population density. It shows the predominant importance of the point sources of fecal indicator bacteria at the scale of the whole watershed. In a scenario in which activated sludge treatment would be complemented with UV in all WWTPs located in this watershed, the non-point sources of fecal indicator bacteria would be dominant. 相似文献
877.
This Φ Ψ study of environmental equity uses secondary quantitative data to analyze socioeconomic disparities in environmental
conditions in the Rijnmond region of the Netherlands. The disparities of selected environmental indicators—exposure to traffic
noise (road, rail, and air), NO2, external safety risks, and the availability of public green space—are analyzed both separately and in combination. Not only
exposures to environmental burdens (“bads”) were investigated, but also access to environmental benefits (“goods”). Additionally,
we held interviews and reviewed documents to grasp the mechanisms underlying the environmental equity situation, with an emphasis
on the role of public policy. Environmental equity is not a priority in public policy for the greater Rotterdam region known
as the Rijnmond region, yet environmental standards have been established to provide a minimum environmental quality to all
local residents. In general, environmental quality has improved in this region, and the accumulation of negative environmental
outcomes (“bads”) has been limited. However, environmental standards for road traffic noise and NO2 are being exceeded, probably because of the pressure on space and the traffic intensity. We found an association of environmental
“bads” with income for rail traffic noise and availability of public green space. In the absence of regulation, positive environmental
outcomes (“goods”) are mainly left up to market forces. Consequently, higher-income groups generally have more access to environmental
“goods” than lower-income groups. 相似文献
878.
为解决猪场废水高色、高浊、高盐的水质特征对藻菌微生物体系处理效果的限制作用,采用电场处理与多种不同微藻/细菌(活性污泥)微生物体系处理相结合,考察了电场对微生物处理猪场废水的效果和生长状况的影响和作用机制.同时,通过对比微藻、微藻-活性污泥、活性污泥3种微生物体系对经电场处理养猪沼液中污染物去除效果及微生物生长情况,考察了电场处理对微生物处理效果的影响和作用.结果表明:电场对养猪沼液色度和浊度均有较好的去除效果,去除率分别为90.43%、99.69%;电场处理后的沼液再进行微生物处理可取得更优的处理效果,微生物对总氮和总磷的去除率最高分别为70.65%、67.30%.此外,微藻-活性污泥共生体系在污染物去除效果和生长状况方面均优于单一微生物体系.微藻-活性污泥体系最终叶绿素a含量为接种时的7.65倍,活性污泥生物量为接种时的1.51倍,远高于单一微生物体系.说明电场处理与微藻-活性污泥生物处理相结合,可以有效提高污染物去除效果,同时获得更多有价的生物质资源,实现更为可观的经济价值,具有广阔的应用潜力和发展前景. 相似文献
879.
藻-菌颗粒污泥(Microalgal-bacterial granular sludge,MBGS)工艺在城市污水生物处理领域引起了越来越多的研究兴趣.胞外多糖(Polysaccharides,PS)是胞外聚合物(Extracellular polymeric substances,EPS)的重要组分,是维持颗粒稳定性的关键物质之一.研究了MBGS中PS的凝胶性能,以及松散结合的胞外聚合物(Loosely bound EPS,LB-EPS)和紧密结合的胞外聚合物(Tightly bound EPS,TB-EPS)中PS的含量、分布及单糖组成,并探究了MBGS的EPS中PS可能的微生物来源.结果表明,MBGS的PS具有凝胶性,主要分布在TB-EPS中,含量为 (40.06±2.30) mg·g-1,其中半乳糖、葡萄糖和鼠李糖为主要单糖组分,而果糖和古罗糖醛酸未被检出.Thauera、Hydrogenophaga、Azoarcus和Acutodesmus是PS的主要微生物潜在来源.本文研究结果阐释了MBGS PS的基本特性,为MBGS工艺的稳定运行提供了理论基础. 相似文献
880.
Yanqing Zhou Chenyang Liu Yili Wang Xiaolin Li Junyi Li Shuoxun Dong Haotian Hao Yao Tong 《环境科学学报(英文版)》2022,120(10):18-29
Bimetallic oxides composites have received an increasing attention as promising adsorbents for aqueous phosphate (P) removal in recent years. In this study, a novel magnetic composite MZLCO was prepared by hybridizing amorphous Zr-La (carbonate) oxides (ZLCO) with nano-Fe3O4 through a one-pot solvothermal method for efficient phosphate adsorption. Our optimum sample of MZLCO-45 exhibited a high Langmuir maximum adsorption capacity of 96.16 mg P/g and performed well even at low phosphate concentration. The phosphate adsorption kinetics by MZLCO-45 fitted well with the pseudo-second-order model, and the adsorption capacity could reach 79% of the ultimate value within the first 60 min. The phosphate adsorption process was highly pH-dependent, and MZLCO-45 performed well over a wide pH range of 2.0-8.0. Moreover, MZLCO-45 showed a strong selectivity to phosphate in the presence of competing ions (Cl−, NO3−, SO42−, HCO3−, Ca2+, and Mg2+) and a good reusability using the eluent of NaOH/NaCl mixture, then 64% adsorption capacity remained after ten recycles. The initial 2.0 mg P/L in municipal wastewater and surface water could be efficiently reduced to below 0.1mg P/L by 0.07 g/L MZLCO-45, and the phosphate removal efficiencies were 95.7% and 96.21%, respectively. Phosphate adsorption mechanisms by MZLCO-45 could be attributed to electrostatic attraction and the inner-sphere complexation via ligand exchange forming Zr/La-O-P, -OH and CO32− groups on MZLCO-45 surface played important roles in the ligand exchange process. The existence of oxygen vacancies could accelerate the phosphate absorption rate of the MZLCO-45 composites. 相似文献