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131.
通过在化工区各主要装置出水口布置监测点,并作连续监测,确定高浓度污水的来源是裂解装置和芳烃装置闪蒸塔真空抽射器液封罐或分离罐的凝液。进一步分析了工艺过程的影响因素,提出改造的措施:裂解的液封罐后增设油水分离罐,分离后的污水再排往污水池;芳烃的真空喷射器前增加冷却器,减少进入喷射器的油气。项目实施后,污水的监测结果全部达到指标要求,使化工区污水场出水连续三年保持100%的合格率。 相似文献
132.
对炼油污水处理场存在的问题进行分析,并结合炼油改扩建后的排水情况,提出了将调节罐改成“罐中罐”隔油设施,新场一级浮选改成CAF涡凹气浮设施,兼性池和活性炭塔以及新场二级浮选和后絮凝池分别改成一个处理单元的生化处理设施,增设高效流砂过滤器和消毒杀菌设施的方案,预计技改后污水处理场出水水质可全面稳定达标,并确保出水水质达污水回用条件。 相似文献
133.
针对目前废旧弹药销毁处理需求日益增长的现状,基于弹药的绿色处理要求,分析常见弹丸装药物理特性,依据装药特性对装药倒空方法进行归纳分类.对比分析7种装药倒空方法的原理、技术及特征,提出弹丸装药倒空方法评价体系,指出电磁感应加热倒空法将成为未来装药倒空的主要发展方向.该分析工作对改善我国废旧弹药处理现状,实现安全、绿色、高效处理具有重要意义. 相似文献
134.
135.
生物质固体成型燃料因其碳中性、氮硫含量低、烟气污染少、便于运输等优势,在供热、供气以及发电方面可以大量替代煤炭、天然气或重油,在有效供能的同时,能够显著减少污染,实现CO2零排放,符合当前社会可持续发展的理念。尽管我国出台了一系列激励政策,但是在产业发展的过程中还存在一定问题,产业发展离国家目标还有一定差距。本文对目前国内外已出台的生物质成型燃料产业政策进行了归纳和总结,并对我国的关键产业政策,如秸秆能源化补贴政策、税收减免政策、环保措施政策、贷款优惠的执行效果做了跟踪调研,对不同政策的执行力度与成效做了评价和分析,最终给出了政策改进建议。 相似文献
136.
This study explores how two different cellulosic ethanol production system configurations (distributed versus centralized processing) affect some aspects of the economic and environmental performance of cellulosic ethanol, measured as minimum ethanol selling price (MESP) and various environmental impact categories. The eco-efficiency indicator, which simultaneously accounts for economic and environmental features, is also calculated. The centralized configuration offers better economic performance for small-scale biorefineries, while the distributed configuration is economically superior for large-scale biorefineries. The MESP of the centralized configuration declines with increased biorefinery size up to a point and then rises due to the cost of trucking biomass to the biorefinery. In contrast, the MESP in the distributed configuration continuously declines with increasing biorefinery size due to the lower costs of railroad transportation and the greater economies of scale achieved at much larger biorefinery sizes, including biorefineries that reach the size of an average oil refinery—about 30,000 tons per day of feedstock. The centralized system yields lower environmental impacts for most impact categories than does the distributed system regardless of the biorefinery size. Eco-efficiency analysis shows that the centralized configuration is more sustainable for small-scale biorefineries, while the distributed configuration with railroad transport is more sustainable for large-scale biorefineries. Compared with gasoline from petroleum, cellulosic ethanol fuel offers sustainability advantages for the following environmental impact categories: fossil energy consumption, global warming, human health impacts by particulate matter, ozone layer depletion, ecotoxicity, human health cancer, and human health non-cancer, depending somewhat on the biorefinery sizes and the system configurations. 相似文献
137.
North American publics are currently much more supportive of second-generation biofuels than of conventional biofuels like corn-based ethanol. But what is the likely future trajectory of consumer acceptance of advanced biofuels? This study considers whether increased awareness of the potential unintended consequences of increasing the production of advanced biofuels could lead to a decline in public support for the technology. Using an experiment embedded in an original survey of Canadian adults, we test for the effect of two anti-biofuels arguments on Canadians' support for policies meant to encourage the production of biofuels. We find that support for biofuels policies was reduced in our experiment when respondents were exposed to an argument about the potential impact of biofuels production on food prices and when they were told that the use of woody biomass as a feedstock for the production of cellulosic biofuels might lead to an increase in commercial logging. In both cases, however, support was reduced only among respondents who did not perceive climate change to pose a significant risk. Overall, our results suggest that public support for advanced biofuels is potentially vulnerable to arguments that focus on the unintended consequences of producing biofuels from non-food feedstocks. 相似文献
138.
The common fermentation of biogenic wastes and sewage sludge in digesters of municipal wastewater treatment plants is a technically feasible and economically viable approach. As the number of rural biogas production sites is steadily increasing, the question has been raised which biomass feedstocks are left available in sufficient quantities to be used for energy generation at wastewater treatment plant level. The contribution of lignocellulosic biomass collected from urban areas is generally neglected within this context. In the present study, 24 urban substrates have been analyzed for their theoretical methane potential, while 13 of them were tested in batch assays for the determination of their practical achievable methane yield. The theoretical evaluation of the methane potential yielded values ranging between 0.393 and 0.576 Nm3 kgVS−1. The methane yields obtained by batch assays showed significantly lower yields, which depends on the individual composition of the substrates in terms of lignin, hemicellulose and cellulose. A GIS spatial analysis for the Rhine-Ruhr metropolitan area was performed to evaluate the feasible capacity of urban biomass as co-fermentation feedstock in digesters of municipal wastewater treatment plants. The analysis revealed that green urban areas provide a significant quantity of biomass of 377 tFM d−1 that could cover 67% of the annual energy demand of twelve typical wastewater treatment plants located in the metropolis. 相似文献
139.
The Flemish renewable electricity support system has struggled to address a number of problematic issues in the past. These included excessive profit margins and general malfunctioning of the green certificate market, as well as a lack of qualification of various existing renewable energy technologies. The Flemish government responded to these issues by introducing major reforms in 2013, including “banding” to differentiate the support for various technologies. However, reliable methods for differentiating renewable electricity technologies and calculating support levels have not been sufficiently developed. The main objective of the 2013 reforms was to reduce support costs, but application of German feed-in tariffs on 18 reference technologies has shown that most projects in Flanders continue to receive high levels of support. The 2013 reforms did not succeed in addressing malfunctioning of the green certificate market. On the contrary, the confidence of investors in renewable electricity plants has decreased as the terms of support can be altered retroactively by adjusting remuneration levels and through political interventions. Future adaptations are likely to be made which will further decrease the overall stability and effectiveness of the system. 相似文献
140.
通过灰成分分析、热重-差示扫描量热-傅里叶红外光谱分析联用(TG-DSC-FTIR)试验,对桉树类生物质锅炉燃烧后飞灰可燃物含量的分析方法进行了研究.结果表明:桉树类生物质燃烧后飞灰中含有多种金属化合物,在空气高温加热过程中会同时发生缓慢氧化反应、碳酸盐分解反应、碱金属氯化物的蒸发过程,影响其中可燃物含量的准确测量;灰中可燃物燃烧温度约在350~550℃范围内,采用低浓度硫酸酸洗对灰样进行预处理,可排除碳酸盐分解反应、碱金属及氯元素的蒸发过程对可燃物含量测量的干扰,且以10K/min及以下的低升温速率加热时灰样中化合物不会发生缓慢氧化反应,使灰中可燃物含量测量结果较为准确. 相似文献