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221.
污水处理厂水质在线监测数据可靠性研究   总被引:1,自引:0,他引:1  
李洁  吴学伟  杜成银  林毅 《环境工程》2009,27(6):109-111
水质在线自动监测系统近年已经开始应用于污水处理厂,在线监测数据的可靠性是污水处理厂推广和应用水质在线监测系统的前提和基础。以广州市某污水厂水质在线监测系统为研究对象,采用对比实验的方法并应用数理统计原理对实验结果进行分析,探讨水质在线监测系统数据的可靠性。经实验及结果分析,污水处理厂水质在线监测系统测得的数据真实可靠,可以用于对污水厂的监督和运行指导。  相似文献   
222.
研究了杂环类(吡啶、喹啉)和酚类(间甲酚、二甲酚、苯酚)有机物对磷酸铵镁结晶法(MAP,magnesium ammonium phosphate)处理废水中氨氮的影响.研究表明,杂环和酚类有机物均对MAP法的除氮效果产生抑制作用,杂环类有机物的抑制作用大于酚类有机物,其中加入吡啶、喹啉、间甲酚、二甲酚、苯酚相比于对照组(21 mg·L-1),氨氮残余浓度分别升高45.17、56.66、43.01、50.68、49.72 mg·L-1.因为络合作用和吸附作用,多组分体系MAP晶体产生的抑制作用强于单一组分体系.  相似文献   
223.
过氧乙酸(peracetic acid,PAA)是一种广谱、高效、环保型消毒剂.近年来,基于活化过氧乙酸的高级氧化技术由于适用pH范围广、产生毒副产物少及具备一定剩余消毒能力等优点在水体有机污染物去除方面受到了越来越多的关注.本文介绍了PAA的性质,综述了活化PAA技术去除水体有机污染物的基本原理及研究现状,分析了活化PAA技术去除有机污染物的主要影响因素(pH及水质组分).最后提出了该技术目前面临的问题及未来发展方向,以期为开发可实际应用于饮用水/污水深度处理的活化PAA技术提供借鉴.  相似文献   
224.
生物膜反应器降解生物质气化洗焦废水   总被引:4,自引:1,他引:3  
陶瓷球作为固定介质 ,接种本实验室保藏的Pseudomonassp1和Pseudomonassp2混合菌种 ,应用生物膜反应器处理生物质气化过程中产生的洗焦废水 ,对反应器运转整个过程的进出水COD浓度、进出水苯、萘、菲、吡啶、喹啉、异喹啉的含量、反应器内和反应器出水含菌量进行测定 ,以了解生物膜反应器处理生物质气化洗焦废水的特性 .结果表明 ,反应器经挂膜、增菌后 ,可达到稳定运转状态 ,有效的控制了反应器内微生物细胞的流失 ,使生物质气化洗焦废水中的有机物得到较好去除 .  相似文献   
225.
第十二届全国人大常委会第十二次会议初次审议了国务院提请审议的《大气污染防治法(修订草案)》,修订草案第四十五条拟授权省、自治区和直辖市人民政府可以采取机动车限行措施,其正当性引起社会的激烈讨论。机动车限行涉及公民所有权的限制,授权的合法性与正当性应受到公法上法律保留原则和比例原则的审查。草案第四十五条未区分高排放与低排放机动车、常态限制与临时限制,模糊地授权地方立法,不符合法律创设的目的性及必要性要求,第四十五条必须进一步明确授权范围。  相似文献   
226.
Mandatory taxes and/or voluntary contributions are commonly adopted as the payment vehicle when eliciting willingness to pay (WTP) in environmental valuation studies. While mandatory taxes may arouse negative feelings, voluntary contributions may lead to strategic behaviour (over bidding) or free riding (under bidding). In this paper, we explore an alternative payment vehicle which avoids the draconian undertones associated with taxes and may be more incentive compatible than a voluntary contribution – a tax that incorporates a refund option. The template for such a payment vehicle is the value added tax charged to tourists in Ireland, but which can be reclaimed on exiting the country. In the context of raising public funds to support the conservation of rural countryside landscape, a comparison is made between the elicited WTP via a mandatory tax and that elicited via the alternative payment method incorporating a refund option. While we observe similar participation rates between the two payment methods, the refund option reveals a higher stated WTP.  相似文献   
227.
Biomass gasification is being considered as one of the most promising technologies for converting low-quality solid biomass fuel into gaseous fuel. Redberry juniper (Juniperus pinchotii), one of the woody species that dominate uncultivated lands in the southern great plains, USA, may have a great potential for bioenergy utilization. In this study, the results of gasification of juniper are presented. Juniper wood chips were gasified in an adiabatic fixed bed updraft gasifier using air and the mixture gas of carbon dioxide and oxygen (CO2:O2) as gasification medium. The effect of gasification parameters such as moisture contents, gasification mediums, and gasification temperature on produced gas properties and the tar yield were investigated. It was observed that oxy fuel gasification (the reaction of woody fuels with carbon dioxide) of juniper resulted in the increase of production of carbon monoxide, especially at higher peak gasification temperatures. As a result, the CO2 gasification resulted in producing higher heating value gas (6264 kJ/nm3 with dilution of CO2 and 19,750 kJ/nm3 inert free) compared to air gasification. For air gasification, it was observed that the updraft gasification produced large amount of the tar in the product gas (more than 100 g/nm3) for the fuels with moisture content between 6% and 11%. Generally, the tar yield increased with the increase of equivalence ratio (er) and moisture content. However, when the fuel moisture content reached 23.5%, the tar yield reduced significantly due low gasification temperature which reduced the less tar cracking.  相似文献   
228.
区域碳权分配原则决定了中国省际碳减排的压力,也是激励各地区转向清洁能源及减排技术创新的基础。本文运用非径向方向性距离函数(NDDF)测算了2011-2014年中国省际全要素碳排放效率(TFC)与技术差距比(CTGR),以分析各地区基于效率最优的碳减排潜力(CRC),进而确定中国区域碳权分配原则。结果表明,各地区减排潜力呈现出与经济发展水平相似的空间分布特征;"十二五"期间海南与安徽两地已处于减排的前沿面,但单一的公平原则挫伤了其持续减排的积极性,而其它低效率省市短时间内无法通过技术效率提升减排能力;无论是单一的公平原则还是单一的效率原则均无法保证各地区碳减排的合理性、稳定性与持久性;而兼顾公平与效率的原则在增加绝对碳排放效率的同时,减少了地区差异。公平与效率原则的动态混合机制更符合中国省际碳减排现状,初期应遵循"公平优先,兼顾效率",随着经济企稳,应转向"效率优先,兼顾公平"。  相似文献   
229.
Adverse consequences to the ecological system and human health caused by impacts potentially attributable to climate change have already drawn great and widespread concern of many scientists and international organizations. However, we still have a hard time determining exactly the impact of climate change on the environment or the damage that climate change inflicts on countries comprising small islands or low-lying lands in light of today’s science and technology. The progress for dealing with the issue of loss and damage has been struggling for a long time from the beginning to the present. In this paper, the author begins by summarizing talks on the concept and the positions of commentators. The author is proposing that the development of future climate negotiations and rule-making process be based on global climate justice as a standard for measuring value. Also, the author proposes that a holistic view of climate justice be established. Generally, three aspects of climate justice can be derived. First, the dimension of human rights protection shows that protection of fundamental human rights is a logical precondition if small-island and low-lying countries are able to achieve climate justice. Second, the definite and traditional concepts of distributive justice and corrective justice hold the view that the principle of common but differentiated responsibilities should be upheld as a basic standard of allocating rights and duties associated with climate change. Third, climate justice requires that any state follow the “no-harm principle,” which is regarded as an international customary rule. According to the principle, the obligation of states to prevent the use of their territory for causing trans-boundary harm to the environment shall be a violation of state responsibility, which incurs international punishment. Then we put forward three remedial approaches in light of climate justice, including the approach of State Responsibility (SR) based on the principles and rules of international human rights law and international environmental law. Based on clear rules, the judge can determine whether the damaging behavior or the damage perpetrated by a state party constitutes a state responsibility. The International Environmental Regulation (IEB), which means solving the problems within the framework established by the Conventions on Climate Change, takes advantage of the market mechanisms and incentives such as fund and insurance support system to relieve or compensate the loss and damage. International Environmental Dispute Settlement Mechanism (IEDSM), which includes the means such as consultations, negotiations, nonmandatory ways and international arbitration, international judicial ways to solve these disputes, functions as a procedural safeguard. As an active promoter of global climate governance, China should no doubt stand by the principle of Common But Differentiated Responsibility (CBDR) and take it as a basis for negotiations, actively strengthen the work of South-South cooperation, fulfill her international climate commitments without reservation, vigorously develop a low-carbon economy, and actively promote international negotiations on the subject of loss and damage.  相似文献   
230.
采用活性焦吸附—曝气生物滤池(BAF)工艺对煤气化废水生化出水进行深度处理。在活性焦投加量2 g/L、吸附时间2 h、BAF生化停留时间4 h的条件下,总COD去除率为85.4%,最终出水平均COD为45.2 mg/L,满足后续双膜法回用工艺要求(COD≤50 mg/L)。活性焦对致色的大分子有机物具有较好的吸附效果,吸附后废水的色度从300倍降至60倍,同时耗氧速率加快,可生化性提高。活性焦的吸附以物理吸附为主,吸附出水没有急性毒性。三维荧光光谱显示:各单元对于酚类的去除均有贡献,小分子组分中的酚类几乎全被去除。  相似文献   
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