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1.
污水厂污泥与厨余垃圾厌氧/混合厌氧消化研究进展   总被引:2,自引:0,他引:2  
李磊 《四川环境》2011,30(2):93-96
本文主要对国内外城市污水厂污泥与厨余垃圾混合厌氧消化的研究进行了综述,介绍了厌氧消化技术在污水厂污泥和厨余垃圾处理处置中的应用,对两种废物单独厌氧消化和混合厌氧消化技术进行了比较,分析了城市污水厂污泥与厨余垃圾混合厌氧消化的可行性以及工艺参数对混合厌氧消化的影响,并对城市污水厂污泥与厨余垃圾的混合厌氧消化技术的研究和应用提出了展望。  相似文献   

2.
介绍了餐厨垃圾的特点,针对餐厨垃圾在厌氧消化过程中容易出现的酸化抑制,梳理了目前常用的缓冲溶液添加、多元物料混合厌氧消化和两相厌氧消化等酸化调控技术,以及处于研发阶段的生物预处理、添加生物炭、驯化培养耐酸型产甲烷菌等酸化调控技术。比较了各种技术的优势与不足,提出未来的技术路径和研究方向,以期为餐厨垃圾厌氧消化工程的稳定运行提供技术支撑。  相似文献   

3.
青霉素废水中含有大量的钠离子,应用“序批式瞬时曝气厌氧消化(ASBR)”工艺能够避免因钠离子的大量存在对厌氧消化所造成的消极影响,保证厌氧消化的顺利进行。  相似文献   

4.
城市生活垃圾中可生化单基质的厌氧消化   总被引:1,自引:0,他引:1  
在厌氧消化系统中,发酵细菌最主要的利用基质是淀粉、纤维素、脂肪和蛋白质等。本试验分别选取米饭、黄豆、芹菜和肥肉为上述四种基质的代表物质,通过对各物质进行的厌氧消化试验,探讨了它们的厌氧消化性能。结果表明。米饭在发酵初期降解速率最快,酸化也最明显。同时将消化初始阶段的pH控制在6.5时能使消化进入产甲烷阶段,没控制的只能停留在水解产酸阶段。将黄豆厌氧消化初期的pH控制在6.5并不能使消化顺利进行。将芹菜厌氧消化的初始pH值控制在6.5时可以加快它的降解速率。肥肉的厌氧消化也只有在对其消化进程控制pH值时才能顺利被降解。同时肥肉在厌氧消化进程中表现出了高产甲烷性能,产甲烷阶段累积产气量达13758mL,占总产气量的93.59%.  相似文献   

5.
厌氧共消化是一种绿色、实用的回收废弃物中能源的技术。本文介绍了厌氧共消化技术的原理,并介绍了美国佐治亚州F. Wayne Hil水资源处理中心采用油脂废弃物(FOG)和含糖工业废水与市政污泥进行连续流厌氧共消化的实际应用案例。结果表明,厌氧共消化可显著提高甲烷产量达2倍以上,甲烷产量随着高浓度有机废弃物负荷率及厌氧消化反应器停留时间的延长而增加,且COD和VS降解率可保持在合理范围内,经济效益显著。  相似文献   

6.
对国内外城市污水污泥与餐厨垃圾混合厌氧消化的研究进行了综述,介绍了厌氧消化技术在以上两种废弃物处理处置中的不足,提出了污水污泥与餐厨垃圾联合厌氧消化的可行性,分析了该技术的研究及应用现状,并对未来的研究热点及方向进行了展望。  相似文献   

7.
王海怀  朱睿 《四川环境》2013,32(1):12-15
提高污泥的脱水性是降低污泥处理难度的必要前提.本文以传统厌氧消化工艺为参照,研究臭氧氧化厌氧消化耦合工艺对化学一级强化污泥脱水挂的影响,以及PAM投加量对厌氧消化污泥脱水性的影响.结果表明,与浓缩污泥相比,传统厌氧消化后污泥脱水性下降了11.8%,而臭氧氧化厌氧消化耦合工艺中污泥没有变化;随着PAM投加量的增加,污泥的脱水性能显著提高;当PAM梗加量为2.0 mg/g DS时,臭氧氧化厌氧消化耦合工艺中污泥的脱水性能达到最佳状态,而当PAM投加量为2.5 mg/g DS时,厌氧消化工艺中污泥的脱水性能才达到最佳状态.  相似文献   

8.
本文以实际猪场沼气废水为研究对象,以ASBR为反应器,接种厌氧消化污泥培养厌氧氨氧化细菌,厌氧氨氧化阶段成功启动后,研究了厌氧氨氧化脱氮最佳运行工艺。试验研究表明,厌氧氨氧化反应适宜的温度在35(±1)℃之间,适宜的pH在7.5—8.0之间,HRT选用24h。当达到最佳运行参数时,NH4+-N的去除率达到87.6%,NO2- -N的去除率达到99.96%。  相似文献   

9.
污泥高固体厌氧消化研究进展   总被引:1,自引:0,他引:1  
厌氧消化是实现污泥的减量化、稳定化和资源化的重要手段,相对于传统的低浓度污泥厌氧消化工艺高固体污泥厌氧消化可以直接利用污水处理厂排放的脱水污泥,具有设施体积小、单位容积产气率较高和水耗及能耗较低等优势。本文综述了近年来污泥高固体消化的研究进展,从污泥高固体厌氧消化的基本特征出发,总结了污泥高固体厌氧消化的影响因素和对反应器的要求;同时对污泥高固体消化存在的搅拌不匀、传质传热困难、有机质降解率偏低、搅拌系统不成熟等问题作了简要分析,这些问题都还有待于深入研究解决。  相似文献   

10.
污泥厌氧消化技术发展应用现状及趋势   总被引:2,自引:0,他引:2  
简介了污泥厌氧消化技术的情况;以美国、欧盟和日本为侧重点,对该技术在国内外的主要研究进展和应用现状做了较详细的描述;提出了国内的污泥厌氧消化技术研究重点,展望了该技术的发展趋势。  相似文献   

11.
我国森林公园旅游开发与规划研究综述   总被引:1,自引:0,他引:1  
在阅读大量文献资料的基础上,试图从森林公园旅游资源调查与评价、森林公园旅游规划与建设、森林公园旅游产品开发、森林公园旅游资源开发问题与对策、森林公园旅游资源的开发与保护、森林公园景观资产的评估、森林公园旅游解说系统等方面对国内有关森林公园旅游开发与规划的研究进行了系统综述。在此基础上,对中国森林公园旅游开发与规划以后的研究进行了展望。  相似文献   

12.
13.
King County, Washington is a part of the rapidly growing Pacific Northwest region. This growth has placed pressure on stream corridors. Past studies about regional stream corridors provide a rich source of information for environmental planners and managers. This article draws on existing literature and case studies to provide guidelines for determining optimal stream corridor widths in a watershed located in King County, Washington.  相似文献   

14.
Recent studies of topographic disorientation from brain injury have focused on describing impairments, detailing neuroanatomical correlates of topographic disorientation, and classifying types of topographic disorientation. Normative models of environmental cognition have been applied in some studies of topographic disorientation, but more work is needed in this area. Few studies have produced data on everyday functioning with topographic disorientation. This paper presents data on compensatory wayfinding behavior in familiar environments, collected through case studies of three individuals with topographic disorientation from brain injury. Structured tests were used to evaluate visuo-spatial impairment, and normative models of wayfinding guided semi-structured and open-ended questioning about wayfinding inside and outside the home. All three-study informants were able to wayfind successfully within the home, though they varied in their ability to travel independently outside the home. Landmarks and scanning were important for orienting for all three subjects. The two subjects who were most able to travel independently also used sequencing of landmarks, directional heading and body position as elements of their wayfinding strategies. The information presented in this paper may prove useful to rehabilitation specialists who are treating brain-injured patients by providing new ideas about methods of compensation, and may contribute to emerging theory regarding impairments of orientation, and normative models of wayfinding.  相似文献   

15.
One of the major hindrances to waste minimisation on a construction site is the difficulty in establishing a methodology and using this methodology to benchmark future construction projects. This paper introduces SMARTWaste, a software tool that has been used to audit, reduce and target waste arisings on a construction site. This tool tries to link the construction process and the waste hierarchy. That is reducing waste on a construction site rather than landfilling it. Three applications of the SMARTWaste software will be discussed using case studies from three different types of construction. An evaluation of these case studies shows that, by implementing a waste minimisation scheme on-site, you can improve material recovery for reuse. Also, by using the waste arisings as a benchmark you can reduce your waste arisings on future sites. Application of SMARTWaste or a similar waste minimisation tool on a wider basis could reduce waste arisings and could result in a built environment that consumed less natural resources and energy, and also produced less pollution and waste. Such a built environment would be environmentally and socially more responsive and responsible.  相似文献   

16.
A number of studies of traditional fuel supply and demand in rural areas of developing countries have been undertaken, but little has been done to make comparable studies for urban populations. This paper reports on two studies undertaken on fuelwood supplies, their transporation and distribution and utilization in the Indian cities of Bangalore and Hyderabad.
Substantial amounts of fuelwood—200 000 tonnes in Hyderabad and 450 000 tonnes in Bangalore—are consumed. Seventy-eight percent of the fuelwood is consumed by households where it is a major source of energy for cooking and heating for low income families. While the researchers did not visit the forest areas which are the source of fuelwood, the quantity consumed is so large as to indicate that deforestation is possibly severe. Recommendations are made to deal with the problem.  相似文献   

17.
The restoration of degraded systems is essential for maintaining the provision of valuable ecosystem services, including the maintenance of aesthetic values. However, restoration projects often fail to reach desired goals for a variety of ecologic, financial, and social reasons. Feasibility studies that evaluate whether a restoration effort should even be attempted can enhance restoration success by highlighting potential pitfalls and gaps in knowledge before the design phase of a restoration. Feasibility studies also can bring stakeholders together before a restoration project is designed to discuss potential disagreements. For these reasons, a feasibility study was conducted to evaluate the efficacy of restoring a tidal freshwater marsh in the Potomac River near Alexandria, Virginia. The study focused on science rather than engineering questions, and thus differed in approach from other feasibility studies that are mostly engineering driven. The authors report the framework they used to conduct a feasibility study to inform other potential restoration projects with similar goals. The seven steps of the framework encompass (1) initiation of a feasibility study, (2) compilation of existing data, (3) collection of current site information, (4) examination of case studies, (5) synthesis of information in a handbook, (6) meeting with selected stakeholders, and (7) evaluation of meeting outcomes. By conducting a feasibility study using the seven-step framework, the authors set the stage for conducting future compliance studies and enhancing the chance of a successful restoration.  相似文献   

18.
Stream temperature changes as a result of forest practices have been a concern in the Pacific Northwest for several decades. As a result of this concern, stream protection requirements for forest lands were first adopted in the early 1970s and have become progressively more stringent. While there have been multiple studies examining the effects of stream protection buffers on water temperature, there are few studies examining temperature patterns over long periods on intensively managed forests. Water temperature in the upper Deschutes River watershed, Washington has been monitored since 1975 and represents one of the longest studies of water quality on managed forests in the Pacific Northwest. This data record, collected from basins of varying sizes, has enabled us to examine the combined effects of hydro‐climatic patterns and forest management on stream temperature. Effects of harvest conducted prior to buffer regulations were clearly identifiable and most pronounced on smaller streams. We were not able to detect any response on larger channels to more recent timber harvest where riparian buffers were required. This analysis also emphasizes that it is critical to account for changing climate when examining long‐term temperature patterns. We found that in many cases the temperature improvements associated with more stringent buffer requirements implemented over the last 35 years in the Deschutes watershed have been offset by warming climatic conditions.  相似文献   

19.
Rural landscapes are highly dynamic and their change impacts on a number of ecological processes such as the dynamics of biodiversity. Although a substantial amount of research has focused on quantifying these changes and their impact on biodiversity, most studies have focused on single dimensions of land use change. This lack of integration in land use change studies can be explained by the fact that data on the spatial, temporal, and ecological dimensions of land use are seldom available for the same geographical location. In this paper, the benefits of taking into account these three dimensions are illustrated with results derived from the Great Britain Countryside Surveys (CS), a large-scale monitoring programme designed to assess change in the extent and ecological condition of British habitats. The overview of CS results presented in this paper shows that (1) changes in land use composition will translate into a variety of spatial patterns; (2) the temporal stability of land use is often lower than can be expected; and (3) there can be large-scale shifts in the ecological condition of the land use types that form our rural landscapes. The benefits of integrated rural landscape studies are discussed in the context of other national monitoring programmes.  相似文献   

20.
Many anticipate that over the next decade, voluntary environmental management system (EMS) standards will take on the same importance in the marketplace as the ISO 9000 quality standards; the draft international EMS standard (ISO 14001) is on pace to be completed by mid-1996. In the United States, despite rapidly growing interest in EMS standards, most companies and regulatory agencies are uncertain about their potential benefits and about the process of developing an EMS. Case studies of EMS implementation, particularly in small and medium-sized companies, are needed to demonstrate the process and identify areas in which further EMS guidance is needed for environmental managers. This article presents seven case studies of EMS implementation in small, medium-sized, and large companies. Each company is participating in an EPA-sponsored Demonstration Project in which a variety of organizations are piloting the implementation of EMS standards (the project is being coordinated by NSF International, a not-for-profit company specializing in environmental and public health standards and certification). The case studies, written by the companies themselves, share experiences of EMS assessment, planning, and implementation, and discuss challenges that are special to particular industries.  相似文献   

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