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171.
用生活污水在常温下培养厌氧颗粒污泥的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
用COD为300mg/L左右的生活污水在常温下(>17·C)启动5L升流式厌氧污泥床(UASB)反应器.接种消化污泥5.6keSS/m3,初始有机容积负荷为0.6kgCOD/(m3·d),水力停留时间为8h.稳定后逐步增加有机容积负荷.一个月后即有颗粒污泥出现,50d后反应器达到稳定的处理效果.运行145d后,污泥中大于0.5mm的颗粒污泥占总重量的73.5%,最大粒径可达3mm,比重为1.07SVI在20左右,污泥中产甲烷菌主要是索氏甲烷丝菌.用颗粒化后的反应器处理生活污水时,水力停留时间可短至6~4h,当水温不低于17℃时,出水COD均低于100mg/L,可达到排放要求。   相似文献   
172.
为解决家用空调器噪声污染纠纷日益增多的问题,以一居民住宅楼为例,对家用空调噪声影响进行了监测与评价,并提出了防治措施。  相似文献   
173.
Graham W. Prescott  William J. Sutherland  Daniel Aguirre  Matthew Baird  Vicky Bowman  Jake Brunner  Grant M. Connette  Martin Cosier  David Dapice  Jose Don T. De Alban  Alex Diment  Julia Fogerite  Jefferson Fox  Win Hlaing  Saw Htun  Jack Hurd  Katherine LaJeunesse Connette  Felicia Lasmana  Cheng Ling Lim  Antony Lynam  Aye Chan Maung  Benjamin McCarron  John F. McCarthy  William J. McShea  Frank Momberg  Myat Su Mon  Than Myint  Robert Oberndorf  Thaung Naing Oo  Jacob Phelps  Madhu Rao  Dietrich Schmidt‐Vogt  Hugh Speechly  Oliver Springate‐Baginski  Robert Steinmetz  Kirk Talbott  Maung Maung Than  Tint Lwin Thaung  Salai Cung Lian Thawng  Kyaw Min Thein  Shwe Thein  Robert Tizard  Tony Whitten  Guy Williams  Trevor Wilson  Kevin Woods  Alan D. Ziegler  Michal Zrust  Edward L. Webb 《Conservation biology》2017,31(6):1257-1270
Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long‐running civil war. With these transitions in mind, we used a horizon‐scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land‐tenure insecurity, large‐scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure‐ and energy‐project planning, and reforming land‐tenure and environmental‐protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.  相似文献   
174.
通过分析近几年城市生活污水排放情况以及生活污水特点表明,城市生活污水已成为水体污染的主要污染源;而现阶段城市排水管网终端集中处理的模式,已不适应城市生活污水的处理和回用,经过对集中处理与分散处理的对比论证,提出了以小区为单元的城市生活污水原位净化再用的可行模式。  相似文献   
175.
本文通过国内外污染场地环境管理比较研究,从完善法律法规角度提出相关政策建议,以期为我国进一步加强污染场地环境管理提供决策参考。具体建议:一是从立法角度看,我国对污染场地管理采取专门立法的模式;二是从框架要素看,进一步建立和完善完整有效的配套法规、标准和指南;三是从责任体系看,建议根据“污染者负担”原则,应明确定义各类责任人在何种情况下承担修复责任;四是从因地制宜的管理目标看,中央政府应制定全国统一的风险管理的政策,并制订指导性的修复筛选值,省市政府可以根据本地区的土地规划和开发需求,制定当地的法规和标准。  相似文献   
176.
通过对“内核烧结法”工艺在不同焚烧状态下的应用研究,开发出了不同类型的垃圾焚烧炉,不断完善生活垃圾焚烧技术。  相似文献   
177.
The objective of this study was to investigate the nitritation performance in a biofilm reactor for treating domestic wastewater.The reactor was operated in continuous feed mode from phases 1 to 3.The dissolved oxygen(DO)was controlled at 3.5–7 mg/L throughout the experiment.The biofilm reactor showed excellent nitritation performance after the inoculation of nitrifying sludge,with the hydraulic retention time being reduced from 24 to 7 hr.Above 90%nitrite accumulation ratio(NAR)was maintained in phase 1.Afterwards,nitratation occurred with the low NH_4~+–N concentration in the reactor.The improvement of NH_4~+–N concentration to 20–35 mg/L had a limited effect on the recovery of nitritation.However,nitritation recovered rapidly when sequencing batch feed mode was adopted in phase 4,with the effluent NH_4~+-N concentration above 7 mg/L.The improvement of ammonia oxidizing bacteria(AOB)activity and the combined inhibition effect of free ammonia(FA)and free nitrous acid(FNA)on the nitrite oxidizing bacteria(NOB)were two key factors for the rapid recovery of nitritation.Sludge activity was obtained in batch tests.The results of batch tests had a good relationship with the long term operation performance of the biofilm reactor.  相似文献   
178.
日光型厌氧好氧一体化技术处理滨海农村污水   总被引:1,自引:0,他引:1  
对日光型厌氧好氧一体化技术处理农村生活污水的效能进行了应用研究。系统的处理量为89t/d,HRT为1.8 d,水解酸化段水力负荷为0.78 m3/(m3·d),接触氧化段水力负荷4.24 m3/(m3·d),稳定运行6个月结果表明:该工艺对CODcr、NH3-N 、TP和SS的去除率分别为73.2%、49.5%、56.1%和79.3%,出水 CODcr、NH3-N、TP、SS的平均浓度分别在60.3 mg/L、20.4 mg/L、2.7 mg/L、26.7 mg/L以下出水水质达到GB18918-2002要求。  相似文献   
179.
回顾了上海市废电池回收过程;通过对2个试点项目实施效果的分析,指出了目前废电池回收存在的误区及原因。在相关宣传教育方面,指出针对废电池回收的宣传教育并未随政策改变而作相应调整,宣传教育形式比较单一,内容相对陈旧,效果不理想。提出了提高公众认识、调整宣教内容、在环境宣传教育中增强专业性和创新性等建议。  相似文献   
180.
The aim of this work was to examine the performance of a sand filter in treating modern olive mill (OMW) effluents after dilution with domestic wastewater on a one-to-one basis. The experimental pilot consisted of a column of opaque PVC, and the sand filter was filled with 50 cm of sand and 10 cm of gravel in the top and the bottom of the filter. The alimentation (4 cm/day) was done sequentially following a 1 day wet/3 days dry cycle. The OMW effluent was very acidic with a pH of 4.12, and had high concentrations of phenolic compounds (7.2 g/L) and total chemical oxygen demand (65 g/L). The percolation of the diluted OMW through the sand filters caused an increase in pH from 4.84 to 8.25 and a 90% removal of total suspended solids. The sand filter treatment also led to important reductions in organic matter (90% of total COD, 83% of dissolved COD and 92% of phenolic compounds) and nutrients (91% of Kjeldahl-nitrogen, 97% of ammonia-nitrogen, 99% of nitrate-nitrogen and 99% of phosphates). The flow rate became very low indicating clogging of the sand pores after 10 weeks. HPLC analysis of the diluted OMW before and after passage through the sand filter showed an important reduction in the toxic monomeric compounds after the treatment.  相似文献   
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