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1.
针对资源循环科学与工程本科专业课程教学,以西安建筑科技大学该专业课程体系为案例,通过对毕业生和专业研讨会调研,分析了课程体系建设的现状和存在的问题。借鉴其他高校资源专业的课程体系和教学内容,通过梳理各门专业课程的教学内容和相互联系,构建了资源专业课程体系课程群,探索了课程体系优化的方法和增加创新实践环节的具体措施。  相似文献   

2.
Solid wastes can be processed for material and energy recovery using a number of unit operations and system approaches. The selection and configuration of unit operations and systems depends upon the characteristics of the wastes to be processed and the uses for recovered secondary materials and for recovered energy forms. The discussion focuses on the types of materials and forms of energy potentially recoverable from solid wastes, waste processing and conversion systems, and design considerations.  相似文献   

3.
Starch acetates with degrees of substitution (DS) of 0.57, 1.11, 1.68, and 2.23 were prepared and extruded with either water or ethanol. The microstructure, physical properties (radial expansion ratio [RER] and unit density), mechanical properties (spring index [SI] and compressibility), and crystalline structure of the foams were investigated. The functional properties were a function of DS and blowing agent type. When water was used as the blowing agent and DS increased, the foams were pale yellow, with rough and uneven surfaces. The cells were dense, with thick cell walls. Lower RER and SI, with higher DS, were associated with high unit density and compressibility. When ethanol was used as the blowing agent, contrary results were observed. The snow-white foams had smooth surfaces, uniform cells, and smooth cell walls. High RER and SI, and low unit density and compressibility were observed. The changes in SI and compressibility with RER also were examined and found to depend on the type of solvent. A crystalline pattern was observed because of the formation of well-ordered structures during extrusion.  相似文献   

4.
包装印刷业VOCs污染特征分析   总被引:2,自引:0,他引:2       下载免费PDF全文
选取了北京市的14家大型包装印刷企业进行现场采样、监测,统计分析了生产工艺和原辅材料,识别了VOCs污染来源和排放节点。根据不同排放节点的特征搭建了相应的采样系统,并以此为基础考察了VOCs的排放特征、臭氧生成潜势和二次有机气溶胶(SOA)生成潜势。结果表明:包装印刷业所排放的VOCs以醇类和酯类为主;乙醇和异丙醇为主要的臭氧前体物,生产线和烘干集气系统排气口为主要的臭氧生成节点;烷烃和醇类为主要的SOA前体物,烘干集气系统排气口为首要的SOA生成节点。  相似文献   

5.
Deposition and storage of fine sediment on channel beds represents an important component of a catchment’s sediment budget and can have important implications for sediment-associated P fluxes, due to storage and remobilisation, and for P concentrations through water–sediment interactions. Spatial and temporal variations in P content and storage in fine bed sediment have been studied in two UK lowland catchments, the Rivers Frome and Piddle in Dorset. Fine bed sediment was sampled in representative reaches on a bi-monthly basis using a re-suspension cylinder, and the resulting samples were analysed for total P, a range of P fractions and particle size. The results demonstrate significant spatial and temporal variability in PP concentrations and storage, with maximum and minimum P concentrations and storage occurring in late summer and winter, respectively. Temporal variations in concentrations reflect residence times of the sediment and ambient P concentrations, while variations in storage are mainly due to hydrological regimes. Spatial variations reflect catchment characteristics, the location of inputs and local variations in hydrological and channel bed conditions.  相似文献   

6.
Vocational Education and Training (VET) is an essential tool for providing waste management and recycling workers with the necessary skills and knowledge needed to beneficially influence their own employment and career development; and to also ensure productivity and safe working conditions within the organisations in which they are employed. Current training opportunities within Queensland for the sector are limited and not widely communicated or marketed; with other States, particularly Victoria and New South Wales, realising higher numbers of VET enrollments for waste management courses. This paper presents current VET opportunities and trends for the Queensland waste management sector. Results from a facilitated workshop to identify workforce requirements and future training needs organised by the Waste Contractors and Recyclers Association of Queensland (WCRAQ) are also presented and discussion follows on the future training needs of the industry within Queensland.  相似文献   

7.
油气开采钻井固体废物处理与利用研究现状   总被引:1,自引:0,他引:1       下载免费PDF全文
对比分析了我国部分地区油气开采钻井固体废物的污染特征,对普通钻井固体废物和含油钻井固体废物的无害化处理与资源化利用技术分别进行梳理和分析,主要包括固化处理技术、生物处理技术、不落地处理技术、资源化利用技术、萃取技术、热解析技术和组合处理技术等。结合当前存在的主要问题针对性地提出了4条对策建议:加强源头控制,减少钻井固体废物产生量;对钻井固体废物进行分质分级区别处理和利用;开发高效、低成本、低能耗的钻井固体废物处理技术,发展联合处理工艺;制定相关政策和标准,加强油气田污染治理的事中事后监管。  相似文献   

8.
An intensive sampling program of physical and chemical parameters has been undertaken at Vassova lagoon, northeast Greece, in order to examine water circulation and estimate the instantaneous and residual fluxes of water, salt, nutrients and chlorophyll-a through the entrance canal of this lagoon. Field data of hydrographic and water quality parameters were collected under neap and spring tidal cycles, and under winter and summer conditions, to account for the fortnight and seasonal effects in the lagoon. The analysis showed that the Eulerian residual transport is positive in direction during both tidal cycles, thus pushing water, salt, nitrate-nitrogen, phosphate-phosphorus and chlorophyll-a inward Vassova lagoon. Tidal pumping was mostly positive during the neap tide and negative during the spring tidal cycle, thus pushing water, salt, phosphorus and chlorophyll-a outwards of Vassova lagoon.  相似文献   

9.
A critical comparison between combustion- and gasification-based waste-to-energy systems needs a deep knowledge of the mass flows of materials and elements inside and throughout the units. The study collected and processed data from several moving grate conventional incinerators and high-temperature shaft gasifiers with direct melting, which are in operation worldwide. A material and substance flow analysis was then developed to systematically assess the flows and stocks of materials and elements within each waste-to-energy unit, by connecting the sources, pathways, and intermediate and final sinks of each species. The patterns of key elements, such as carbon, chloride and heavy metals, in the different solid and gaseous output streams of the two compared processes have been then defined. The combination of partitioning coefficients with the mass balances on atomic species and results of mineralogical characterization from recent literatures was used to estimate a composition of bottom ashes and slags from the two types of waste-to-energy technologies. The results also allow to quantify some of the performance parameters of the units and, in particular, the potential reduction of the amount of solid residues to be sent to final disposal.  相似文献   

10.
田祎  叶旌  王玉晶  田宇  赵静  菅小东 《化工环保》2018,38(4):481-486
通过解析《关于汞的水俣公约》的管理对策及措施,分析了我国重金属污染防治管理中存在的问题及开展对策研究的必要性。以重金属污染防治管理战略、基础研究、政策法规和标准体系建设、信息管理体系建设、技术研发和推广、监督管理能力建设、协调机制建设等领域为切入点,分析得出了各领域存在的关键问题并提出了对策建议。  相似文献   

11.
生物吸附在染料废水处理中的应用   总被引:9,自引:0,他引:9  
生物吸附是微生物细胞和其它物质发生的一系列非发酵关联的吸附过程,其主要作用包括物理和化学吸附、静电作用、离子交换、络合、螯合、微量沉淀等。与生物降解相比,生物吸附不会产生有毒的代谢产物,为染料废水的处理和回收提供了一条经济可行的途径。综述了微生物对染料吸附的作用机制及影响因素如pH、温度、染料初始浓度等,介绍了生物吸附的发展现状及前景。  相似文献   

12.
Compost can provide a rich organic nutrient source and soil conditioner for agricultural and horticultural applications. Ideal compost amendment rates, however, vary based on starting material and compost maturity or their interaction, and there is little consensus on appropriate methods to gauge maturity. In this study, electrical conductivity, carbon-to-nitrogen ratio, and carbon mineralization measurements were made on compost-amended soils and compared to phytotoxicity measured as cress (Lepidium sativum) germination. Cress germination in soil and compost mixtures incubated for 8-10 days significantly decreased with increasing electrical conductivity and carbon mineralization rate of the mixture and with carbon mineralization rate and mineralizable carbon associated with the compost. Cress germination was not related to carbon-to-nitrogen ratio or pH of soil and compost mixtures. The electrical conductivity of the soil and compost mixtures significantly decreased with decreasing mineralizable carbon suggesting that compounds contributing to electrical conductivity were present in the compost and decomposed upon soil amendment. The results of this study indicate that measurements of mineralizable carbon and mineralization rate of composts in soil, and electrical conductivity and mineralization rate of soil and compost mixtures, can be used as indicators of compost maturity.  相似文献   

13.
Microorganisms which can assimilate a new polyester synthesized from polyethylene glycol (PEG) as a dihydroxyl compound and phthalic acid as a dicarboxyl compound were isolated from soils by enrichment culture techniques. Two cultures, K and N, were obtained: Culture K grew on PEG 4000 polyester and culture N assimilated PEG 6000 polyester. Each culture included two bacteria indispensable for the degradation of polyesters: bacteria K1 and K2 for PEG 4000 polyester-utilizing culture K and bacteria N1 and N2 for PEG 6000 polyester-utilizing culture N. Bacteria K2 and N2 were responsible for the hydrolysis of ester bonds in a polyester and both were identified as the same species,Comamonas acidovorans. Bacteria K1 and N6 could assimilate PEG as a sole carbon and energy source. Both are Gram-negative, non-spore-forming rods and resembled each other on their colony characteristics, although strain K1 could not grow on PEG 6000.C. acidovorans N2 (K2) grew on dialkyl phthalates (C2–C4) and phthalate and tributyrin, but not on PEG, diphthalic PEG, and PEG phthalate polyesters. Their culture supernatant and washed cells hydrolyzed PEG (400–20,000) phthalate and sebacate polyesters.C. acidovorans had higher esterase activity toward PEG phthalate, isophthalate, and terephthalate polyesters than known esterase and lipases. The esterase seemed to be an extracellular one and attached to the cell surface.  相似文献   

14.
This paper presents and critically analyses the current waste electrical and electronic equipment (WEEE) management practices in various countries and regions. Global trends in (i) the quantities and composition of WEEE; and (ii) the various strategies and practices adopted by selected countries to handle, regulate and prevent WEEE are comprehensively examined. The findings indicate that for (i), the quantities of WEEE generated are high and/or on the increase. IT and telecommunications equipment seem to be the dominant WEEE being generated, at least in terms of numbers, in Africa, in the poorer regions of Asia and in Latin/South America. However, the paper contends that the reported figures on quantities of WEEE generated may be grossly underestimated. For (ii), with the notable exception of Europe, many countries seem to be lacking or are slow in initiating, drafting and adopting WEEE regulations. Handling of WEEE in developing countries is typified by high rate of repair and reuse within a largely informal recycling sector. In both developed and developing nations, the landfilling of WEEE is still a concern. It has been established that stockpiling of unwanted electrical and electronic products is common in both the USA and less developed economies. The paper also identifies and discusses four common priority areas for WEEE across the globe, namely: (i) resource depletion; (ii) ethical concerns; (iii) health and environmental issues; and (iv) WEEE takeback strategies. Further, the paper discusses the future perspectives on WEEE generation, treatment, prevention and regulation. Four key conclusions are drawn from this review: global amounts of WEEE will continue unabated for some time due to emergence of new technologies and affordable electronics; informal recycling in developing nations has the potential of making a valuable contribution if their operations can be changed with strict safety standards as a priority; the pace of initiating and enacting WEEE specific legislation is very slow across the globe and in some cases non-existent; and globally, there is need for more accurate and current data on amounts and types of WEEE generated.  相似文献   

15.
This paper presents guidelines that can be used by managers of healthcare facilities to evaluate and assess the quality of resources and waste management at their facilities and enabling the principles of sustainable development to be addressed. The guidelines include the following key aspects which need to be considered when completing an assessment. They are: (a) general management; (b) social issues; (c) health and safety; (d) energy and water use; (e) purchasing and supply; (f) waste management (responsibility, segregation, storage and packaging); (g) waste transport; (h) recycling and re-use; (i) waste treatment; and (j) final disposal. They identify actions required to achieve a higher level of performance which can readily be applied to any healthcare facility, irrespective of the local level of social, economic and environmental development. The guidelines are presented, and the characteristics of facilities associated with sustainable (level 4) and unsustainable (level 0) healthcare resource and wastes management are outlined. They have been used to assess a major London hospital, and this highlighted a number of deficiencies in current practice, including a lack of control over purchasing and supply, and very low rates of segregation of municipal solid waste from hazardous healthcare waste.  相似文献   

16.
Making remediation and risk management decisions for widely‐distributed chemicals is a challenging aspect of contaminated site management. The objective of this study is to present an initial evaluation of the ubiquitous, ambient environmental distribution of poly‐ and perfluoroalkyl substances (PFAS) within the context of environmental decision‐making at contaminated sites. PFAS are anthropogenic contaminants of emerging concern with a wide variety of consumer and industrial sources and uses that result in multiple exposure routes for humans. The combination of widespread prevalence and low screening levels introduces considerable uncertainty and potential costs in the environmental management of PFAS. PFAS are not naturally‐occurring, but are frequently detected in environmental media independent of site‐specific (i.e., point source) contamination. Information was collected on background and ambient levels of two predominant PFAS, perfluorooctane sulfonate and perfluorooctanoate, in North America in both abiotic media (soil, sediment, surface water, and public drinking water supplies) and selected biotic media (human tissues, fish, and shellfish). The background or ambient information was compiled from multiple published sources, organized by medium and concentration ranges, and evaluated for geographical trends and, when available, also compared to health‐based screening levels. Data coverage and quality varied from wide‐ranging and well‐documented for soil, surface water, and serum data to more localized and less well‐documented for sediment and fish and shellfish tissues and some uncertainties in the data were noted. Widespread ambient soil and sediment concentrations were noted but were well below human health‐protective thresholds for direct contact exposures. Surface water, drinking water supply waters (representing a combination of groundwater and surface water), fish and shellfish tissue, and human serum levels ranged from less than to greater than available health‐based threshold values. This evaluation highlights the need for incorporating literature‐based or site‐specific background into PFAS site evaluation and decision‐making, so that source identification, risk management, and remediation goals are properly focused and to also inform general policy development for PFAS management.  相似文献   

17.
我国CCUS技术发展,迫切需要政策制度的积极引导和技术标准的强力支撑。阐述了我国发展CCUS技术的基本原则和相关政策;跟踪了国内外CCUS技术发展动态及其标准研究现状;重点分析了美国及欧盟在CCS相关政策、法规和标准方面的主要成果;依据我国CCUS发展规划和技术发展路线图,提出了我国CCUS技术发展与标准建设的相关建议。  相似文献   

18.
In situations where groundwater supplies have been impacted by volatile organic compounds (VOCs), such as tetrachloroethene (PCE), and the source has not been identified, the costs to identify the source and plume migration patterns may be extremely high. The costs for an investigation increase with the number and depth of borings and the number of samples that are collected and analyzed. An environmental investigator and the Arizona Department of Environmental Quality (ADEQ) have successfully utilized passive soil gas (PSG) surveys in Arizona to cost‐effectively investigate VOC impacts to groundwater and identify potential sources of impact. PSG surveys are minimally intrusive, and more samples can be collected for the same cost when compared to active soil gas surveys and conventional soil and groundwater sampling programs. The result is a surficial representation of the contaminant plume and the location of “hot spots,'' which are the potential sources. This provides a better understanding of the nature and extent of the impact and allows for a focused subsurface investigation, which subsequently reduces drilling and sampling costs. © 2008 Wiley Periodicals, Inc.  相似文献   

19.
介绍了近10年报道的不同构造人工湿地(CW)的污水处理性能及CW中微生物、植物、动物的相关研究进展.分析了各种CW构造优缺点、CW与其他技术的结合、CW微生物群落的特征、影响因素和研究手段、CW植物与动物对CW处理性能的贡献及作用机制.提出今后应重点研究:复合人工湿地(ICW)工艺优化;CW强化技术及其参数;CW微生物...  相似文献   

20.
Per‐ and polyfluoroalkyl substances (PFAS) are fluorinated compounds and the active ingredient in aqueous film‐forming foam (AFFF). AFFF has been identified as a significant source of PFAS contamination in groundwater. PFAS are also present in many other industrial and consumer products and their manufacture and use has led to numerous contaminated sites. Human health risks have been identified with studies linking firefighter cancers to training facilities where AFFF was used. Given the widespread release of these compounds to the environment and their potential health risks, understanding their mobility characteristics is important. This article details the occurrence and behavior of these substances in groundwater systems to help guide the emerging fields of PFAS investigation and remediation. Background is presented on AFFF and PFAS source characteristics, including common industrial and consumer PFAS sources. In addition, chemical properties, sorption and retention parameters, and observed transformation properties of PFAS and related compounds are discussed. Finally, knowledge gaps are identified for future laboratory and field studies.  相似文献   

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