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931.
To reduce the consumption of freshwater in the laundry industry, a new trend of closing the water cycle has resulted in the reuse/recycling of water. In this study, the performance of a full-scale submerged aerobic membrane bioreactor (9 m3) used to treat/reuse industrial laundry wastewater was examined over a period of 288 days. The turbidity and total solids (TS) were reduced by 99%, and the chemical oxygen demand (COD) effluent removal efficiencies were between 70% and 99%. The levels of COD removed by the membrane were significantly greater than the levels of biodegraded COD. This enabled the bioreactor to sustain COD levels that were below 100 mg/L, even during periods of low wastewater biodegradation due to bioreactor sludge. An economic evaluation of the membrane bioreactor (MBR) system showed a savings of 1.13 € per 1 m3 of water. The payback period for this system is approximately 6 years. The energy and maintenance costs represent only 5% of the total cost of the MBR system. 相似文献
932.
A holistic evaluation of the feasibility of producing 100% recycled mixtures is presented. Eleven technologies readily available for producing 100% Reclaimed Asphalt Pavement (RAP) hot asphalt mixtures are described in the article and the complementary video (http://youtu.be/coj-e5mhHEQ). The recorded performance of 100% RAP mixtures is analyzed along with identification of typical high RAP distresses. Recommended mix design procedures and the best RAP management strategies are described. A cradle-to-gate analysis of environmental effects indicated 18 kg or 35% CO2eq savings per t of produced 100% RAP asphalt mixture compared to virgin mix, while cost analysis showed at least 50% savings in material related expenses. 相似文献
933.
934.
提出一种新纳米零价铁反应器(Nanoscale Zero-Valent Iron Reactor,简称NIR)及"混凝沉淀+纳米零价铁"处理工艺,通过实际生产废水进行中试,考察和研究该工艺和NIR技术处理江苏省某市印刷电路板(Printed Circuit Board,简称PCB)工业园区废水的效果。结果表明,此工艺对PCB生产废水中Cu、TP及COD Cr去除率分别可达到97.3%、73.7%、26%,其中Cu处理效果最佳;XRD结果表明,纳米零价铁(Nanoscale Zero-Valent Iron,nZVI)与PCB生产废水反应后含有γ-Fe2O3、Fe3O4、γ-FeOOH、CuO、Cu2O、Cu0等产物。"混凝沉淀+纳米零价铁"工艺处理废水时具有处理效果好、工艺耐冲击性能好、产泥量小、不易造成二次污染等优点。 相似文献
935.
936.
结合深圳盐田区城中村污水完善改造设计及施工服务中所遇到的问题,提出为彻底解除雨水污水混流现象而采取的措施和方法,以作为今后城中村雨水污水分流制改造过程中的借鉴或参考。 相似文献
937.
二氧化氯混合消毒剂是新一代广谱高效消毒剂,消毒能力是次氯的3~5倍.二氧化氯发生器性能安全可靠,运行稳定,操作方便,对人体无不良作用.介绍了二氧化氯混合消毒剂在中国长城铝业公司职工医院含菌废水处理的应用实例. 相似文献
938.
939.
大城市污水处理工艺的经济选择因素 总被引:3,自引:0,他引:3
城市污水处理设施的建设是今后改善我国城市环境的重要任务之一,其具体工艺和技术的选择除了对污水治理的结果产生影响外,更重要的是直接影响对设施建设的投入强度和运行效果,建议从经济和技术结合的角度研究比较各种技术和工艺,去探讨经济技术最佳结合的方法。 相似文献
940.
Rosario Perez Espejo 《Environment, Development and Sustainability》2006,8(3):391-411
The objective of this article is to address the environmental costs of pig farms in the La Piedad region Mexico, through an
analysis of the standard on wastewater discharges to national water bodies. Field work was carried out from April to September
1999; a survey was conducted on 23 farms and samples of wastewater were taken on 11 farms. Pig production is the third most
important system in Mexican livestock production. Heterogeneity in production systems, dependence on imported inputs (genetics
and feed grains), and weak internalization of environmental costs are the main characteristics of pig production in Mexico.
With no specific environmental regulations on intensive livestock activities at the municipal or state levels, Mexican Official
Standard 001 on wastewater discharges is the only environmental obligation that pig farms must meet. Standard 001 on wastewater
contains the maximum permissible limits for 20 contaminant parameters, and is based on a cost-benefit analysis that points
to secondary treatment for the regulation’s economic viability. Investment in treatment systems and the fees that pig producers
must pay when they fail to comply with the limits stipulated in the regulation, are estimated assessed as an approach to environmental
costs. In order to remain within the limits in the standard, pig farms must invest in tertiary treatment, and that makes meeting
the standard unaffordable for this sector. 相似文献