岷江上游水电工程临河型弃渣场水土流失量预测研究

根据2006年7月对岷江上游部分水电站弃渣场的调查,统计分析各渣场现有堆渣量与设计堆渣量的差值,从而得出各渣场流失量与堆渣量的比值,即为流弃比;分析流弃比产生的原因和组成,提出岷江上游地区以石料为主的临河型渣场流弃比取值范围,为以后该地区和其他类似地区的同类型渣场的水土流失预测提供参考.     

中国农村生活垃圾的产生量与物理特性分析及处理建议

中国农村生活垃圾对生态环境的污染日益严重,为给农村生活垃圾的管理提供相应的理论支撑和技术支持,促进"新农村"的建设,该文基于对西部6省18县59村580户农户的现场调研和全国25个省(市)128篇文献调研的数理统计,对中国农村生活垃圾的来源、产生率、产生量、组分、容重、可压缩性等特征进行了全面、系统的归纳总结与分析。结果表明:中国农村生活垃圾产生率介于0.034~3.000 kg/(人·d)之间,中位值为0.521 kg/(人·d),2014年产生量达到1.48亿t,具有来源广泛且分散、产率低、产量高、增长迅速、区域差异显著等特点。生活垃圾主要组分包括厨余类、灰土类、橡塑类和纸类,其湿基质量累计百分比达到了83.61%,区域差异显著;与城市生活垃圾组分相比,具有低厨余和金属、高灰土含量的特点,并逐渐趋于城市化。生活垃圾的容重介于40~650 kg/m~3之间,平均值为263 kg/m~3,可压缩性较好。根据生活垃圾特性,在实施"村收集-镇运输-县处理"管理模式的农村,建议采用压缩式中转站和垃圾车进行收运;在有条件的农村地区,可逐步开展垃圾分类收集,将厨余和灰土从生活垃圾中分离后就地消纳。     

Composting Food Processing Waste in the European Economic Community

For more than half a century, large food processing companies, faced with mounting solid waste disposal problems, have opted for landfilling. Other options, concentrating on utilization, are now being increasingly explored. Energy recovery (ethanol and methanol) and fodder production from food processing residuals in some cases are valid solutions. Of the many alternatives to food recovery waste disposal, composting seems to be an effective method. Managed properly, research has shown that composting can produce a nutrient-rich soil amendment; odors can be controlled during the transformation process and in the final product. The process is competitive and cost-effective environmentally, completes the biological chain and returns to the soil what has been taken from it. For these reasons, composting seems to be the best candidate to solve problems connected with food factory waste disposal.     

Sorption Behavior of Arsenate by Mg-Bearing Minerals at Hyperalkaline Condition: Implications for Oxyanions Sequestration During the Use and Disposal of Alkaline Wastes

The utilization and disposal of alkaline waste materials such as slag and coal fly ash as cement aggregates and raw materials in cement manufacturing can pose environmental and health hazards because these waste materials usually contain elevated concentration of toxic elements. This study examined the possibility of controlling the pore water chemistry of these waste materials in order to induce the secondary mineral formation of Mg-bearing minerals as major sorbing solids for oxyanions during the utilization and disposal of alkaline wastes. The formation of Mg-bearing minerals was examined at ambient temperature and alkaline pH conditions in the Mg?CSi?CAl system. The interaction of Mg-bearing minerals with oxyanions using arsenate as an analog was examined during and after mineral formation. The results revealed that the generated Mg-bearing mineral phases were smectite and brucite in Mg?CSi system and hydrotalcite and serpentine in Mg?CSi?CAl system. Moreover, hydrotalcite, serpentine, brucite, and smectite phases formed under low Si ratio showed high sorption capacity for arsenate, but only high Al content hydrotalcite and serpentine showed substantial irreversible fraction of sorbed arsenate. Hence, the generation of these kinds of hydrotalcite and serpentine phases as scavengers for oxyanions must be considered during the utilization and disposal of alkaline wastes.     

典型粪污处理模式下规模养猪场农牧结合规模配置研究Ⅰ.固液分离 液体厌氧发酵模式

不同粪污处理模式下畜禽粪便的养分损失存在较大差异,从而影响其后续地农田利用。固液分离-液体厌氧发酵模式是当前我国畜禽粪污处理的主要模式之一。研究粪污固液分离-液体厌氧发酵处理模式下规模养猪场农牧结合适宜规模配置对于减少畜禽粪便污染、促进畜牧业可持续发展具有重要意义。本研究根据猪群体结构比例、废弃物产生量及氮磷含量、废弃物处理利用过程中养分损失率以及作物氮磷钾需求量等资料,以存栏万头猪场为例,采用分步逐级计算的方法估算了典型粪便处理模式——固液分离-液体厌氧发酵下,规模养猪场废弃物完全消纳的不同种植模式农田匹配面积,并研究了基于作物养分需求的不同种植模式农田畜禽粪便承载量。结果表明:固液分离-液体厌氧发酵粪便处理模式,以沼液安全消纳为目标,万头猪场需要配置的最少农田面积分别为粮油作物地12.4~13.7 hm2,或茄果类蔬菜地14.2~17.9 hm2,或果树苗木地16.4~51.3 hm2。以有机肥和沼液全部在农田安全消纳为目标,万头猪场需要配置的最少农田面积分别为粮油作物地299.3~312.9 hm2,或茄果类蔬菜地145.1~179.0 hm2,或果树苗木地553.1~1 343.8 hm2。因此,规模养猪场应根据猪养殖数量及其周边农田面积,选择适宜的有机肥利用方式及种植作物类型,因地制宜,合理调控。     

Bodengesellschaft auf und neben einer Mülldeponie

Soil association upon and near to a waste disposal site Soils of a waste disposal site and a moraine slope in the neighbourhood were mapped and analyzed, to see whether they are related soils and that means soil associations after Schlichting. Erosion/sedimentation-processes as well as translocated gases and waste fluids influenced the different soils of the landscape so that these soils are related with each other by soil forming processes.     

基于关系与结构嵌入的农户农业废弃物绿色处置行为分析

如何在推进农业经济快速发展的同时又兼顾环境保护,构筑人与自然"生命共同体",已是中国推进乡村振兴战略不可回避的重要问题。区别于既有研究,运用倾向得分匹配方法(propensity score matching)克服样本选择性偏差引起的内生性,探讨了社会学"强嵌入"因素中的关系嵌入和结构嵌入对农户农业用资材废弃物绿色处置行为的影响。结果发现,结构嵌入对农户农业用资材废弃物绿色处置行为具有显著的正向促进作用,关系嵌入的作用并不明显;而家庭劳动力数量、兼业、家庭耕地面积以及农业收入比例等"零嵌入"因素是影响关系嵌入与结构嵌入的关键。基于此,该文认为,应通过建立农民利益诉求表达渠道与责任监督机制,鼓励农户加强与种养殖大户交流与沟通,营造良好的社会环保氛围等方式改善农户农业用资材废弃物绿色处置行为,以推进农业产业绿色转型。     

Preliminary evaluation of eggshells as a source of phosphate on hydroponically grown tomato (Solanum lycopersicum L.) seedlings

Abstract

Phosphorus (Pi) is one of the most limiting factors in plant nutrition as it is the least mobile and available nutrient to plants in most soil conditions. The management of Pi fertilization in agriculture raises ecological, economic, and social issues, since phosphate rock minerals are the only significant global resources of Pi and they will be rapidly depleted. Eggshell waste is a big problem for food companies producing different types of egg products, since the eggshell waste is very often simply discarded and disposed at landfills, with high costs related to their disposal. The aim of this work was the characterization of eggshells as a Pi source for plants, using tomato (Solanum lycopersicum L cv Marmande) as a model species. Plants were grown hydroponically being exposed to adequate and limited Pi availability, with or without eggshell powder. Plant growth performance was characterized by analyzing changes in fresh weight, protein, chlorophyll concentration, carotenoid content, and measuring the plant’s capability to accumulate phosphate. The addition of eggshell powder to the nutrient solution significantly improved plant growth and increased protein and chlorophyll concentration, not only with respect to P-deficient control, but also with P-sufficient ones. Furthermore, eggshell powder significantly increased Pi accumulation in P-deficient plants, suggesting that eggshell waste could be a suitable material as Pi source for tomato plants, thus contributing to the environmentally friendly disposal of this waste.     

Solid waste management in Santa Barbara county

Santa Barbara County commenced to modernize its solid waste system in 1960 by passage of an ordinance by the Board of Supervisors assuming the responsibility for waste disposal and regulation of refuse collection. Private collectors were licensed, with collection service, equipment and rates controlled by the County. Transfer facilities were put in service in the populous south coast area in 1967 with a sanitary fill site planned to become a future recreation area. After several years of operation, costs of transfer and disposal are four dollars per ton. Although totally funded by the County plus revenues up to this year, the refuse disposal operation became an ‘enterprise fund’ on July 1, 1974 and will thereafter operate essentially as a private business. Financial planning for refuse disposal in Santa Barbara County has assumed continuation of the sanitary fills and transfer system until 1980, but the new Solid Waste Management Plan for the County now required by the State will evaluate resource recovery, power generation and other possible alternatives. Based on these studies, the plan may lead to a new phase in improvement of solid waste management in the County.     

Evaluation of contaminated groundwater cleanup objectives

Uranium tailings are generated as solid and liquid wastes in uranium mining/milling operations. Since most of the uranium deposits in the world have low grades, millions of tonnes of such wastes are produced annually. Often, the uranium tailings are locally disposed of, using sites with suitable conditions to construct tailings basins. The main concern during the operation of a disposal site is the presence of radium in the liquid phase which overflows from dewatered tailings. This barium is precipitated by adding proper chemical reagent. The potential environmental hazards of uranium tailings arise when the disposal site is abandoned after the decommissioning of the uranium mill. Huge amounts of solid waste as small particles of depleted ore remain in place. Top soils are usually for soil stabilization and for controlling radon emissions. Hence water infiltration through uranium tailings presents a potential hazard to underground aquifers. Water plays a dual role by triggering a sequence of reactions and by carrying contaminants away from the wastes sites. The situation is more serious in a country like Canada, where the precipitation rate is higher than the evaporation rate and the water table is about one metre beneath the ground surface. For permanent disposal of uranium tailings, either the hazardous constituents of these wastes have to be isolated from the percolating water, or the subsoils must have acceptable sealing and sorptive characteristics. The first approach is effected by blending proper solidifying reagents with the tailings in order to totally block them from the leaching effects of aggressive pore water. Solid waste treatment may prove costly in additive usage and the blending operation. The leaching of toxic constituents, however, becomes effective so long as the tailings are in a loose form. This is because of the acid-generating properties of the pyrite, a substantial constituent (up to 8% wt) of the tailings. Two types of contaminants tend to leave the solid and migrate to the pore water. These are the heavy metals and the radioactive elements, both of which are hazardous for their toxicity and persistence. The sorptive and neutralizing capacities of the underlying soils have to be carefully examined and measures have to be taken to stop the progression of acidic interstitial water. This paper focuses on three aspects of crucial importance to the permanent disposal of uranium tailings. These are: leaching in uranium tailings, sorption on natural geological barriers, and radium immobilization.     

Environmental impact of radioactive waste management in the nuclear industry

Radioactive wastes from the nuclear industry are classified into low, intermediate and high activity levels, and problems of their storage and release examined in detail. Current means of storage are considered with reference to processing of low and intermediate level liquid waste, processing of high level waste, processing of airborne waste, and ground disposal and processing of solid waste. Release is discussed in terms of effluent release limits, monitoring and the use of permanent records, impact of release to the human environment, impact of release to the material environment, and guides for preventing accidental release. Contamination of the shore of Lake Huron from radioactive fallout is discussed as a particular example. Problems to be solved are identified in three main areas: gaseous wastes, actinide-contaminated wastes, and permanent disposal, and some specific suggestions for study are made.     

Solid Wastes In Urban And Rural Areas Of Ibadan,Nigeria: Composition,Treatment And Public Health Concerns

The composition of solid waste produced at various locations in Nigeria differs considerably because the amounts generated and the constituents thereof are determined by social customs and living standards. Nigeria has undergone extensive industrial development which has often changed the composition of domestic solid waste as well as agricultural wastes. The disposal and utilization of these mixed wastes has presented new risks and problems for our society and environment. Though most solid waste in Nigeria contains little human and animal material, pathogenic organisms affecting both continue to be present. Potential risks to human health and the environment that can arise from domestic solid waste disposal and utilization in Nigeria include pollution of water and air, accidents, contact contamination and breeding sites for flies and rodents. There also are long-term problems in relation to the human food chain.     

The Effect of Yatagan Thermal Power Plant (Mugla,Turkey) on the Quality of Surface and Ground Waters

Yatagan thermal power plant consumes annually 5.4 million tons of coal and the annual production capacity of the plant is 3.78 billion KWh. The thermal power plant uses 15 000 tons of coal and discharges 5000 tons of fly and bottom ash daily to the disposal site. The waste is dumped using conveyer belts and pipes into a dam founded on metamorphic rocks. However, as the waste hills formed, the water level reached the karstic marbles that over lay schist. Water leaches through dried waste hills and karstic marbles, ultimately adversely affecting the quality of ground and surface waters. The concentrations of major and minor ions were determined on water samples taken at 2 points in the dam, 5 points in surface water and at 21 points in groundwater located in the vicinity of the waste disposal site, total of 28 samples, for three years. The chemical analyses revealed that the concentrations of Ca²⁺, Cd²⁺, Pb²⁺, Sb²⁺ and SO₄ ^2- in some samples exceed the Turkish Drinking Water, the U.S. EPA and WHO limits. Isotope analyses were carried out to determine the origins of waters, which showedthat contamination is taking place in the vicinity of the waste disposal site.     

Plastics waste handling practices in solid waste management

In order to see the impact of plastics on the overall solid waste picture, the sources and nature of wastes generated by that industry will be defined. At one end of the spectrum are industrial wastes resulting from plastics formation and from packaging and transfer. Fabrication follows and then the intermediate markets. Finally, there is the consumer. Each step generates a waste stream. The options for disposal or recycle are discussed for each waste source and the economics included are reviewed. The fate of plastics in the environment has been of concern to some, principally because plastics generally do not disappear very fast. Activity in this sector will be discussed. Engineering and other technical input for all waste handling follows economic reality and higher scrap values are resulting in new market potentials for waste plastics. The emergence of energy as a key decision point in environmental concern has highlighted the energy value of waste plastics as fuel. Current activity in this area will be discussed. An increased legislative role in solid waste management is needed. Some of the currently considered legislative practices that help and that hurt the industry's ability to assist in managing the solid waste problem will be reviewed.     

Characteristics of Medical Waste in Taiwan

The purpose of this study was threefold: to investigate the types and amounts of medical waste from various hospitals in Taiwan; to analyze residues from incinerated medical waste for heavy metal content; and to measure the amount of infectious and general medical waste per bed per day and determine the ratio of infectious to general medical waste. Information was first obtained on the amounts of medical waste produced per bed per day and on waste handling and treatment. Next, residue samples were taken from incinerators and analyzed for heavy metal content. Third, daily records concerning waste content and weight from one hospital were kept over the period of one year. Chromium (Cr) and zinc (Zn) concentrations were significantly higher in medical waste than in general waste. Medical waste fluctuated significantly over the one-year period. Records showed that wastes containing dialysis material and wood/cotton materials were found to have the highest weight and wastes containing human organs had the lowest weight. Results of the present study underscore the need for all hospitals to effectively separate waste for proper treatment and disposal, particularly waste that produces residues which may be hazardous to the environment. In addition, hospitals also need to recycle or reuse certain materials in order to reduce waste production.     

Impact of Composting Food Waste with Green Waste on Greenhouse Gas Emissions from Compost Windrows

Windrow composting of green waste as an alternative to green waste disposal in landfills requires an understanding of the impacts on greenhouse gas (GHG) emissions and the development of effective and efficient management strategies to reduce these emissions. The addition of food waste to green waste compost operations is becoming more common, but its effect on GHG emissions is less understood. As more food waste diversion occurs as a result of recent implementation of climate smart policies in California, more information is needed to address the sustainability of composting different combinations of waste types. We monitored GHG emissions from compost windrows comprised of green waste alone and a green/food waste mixture (green waste : food waste = 9:1, by wet weight) at the University of California, Davis Student Farm in 2016 using a modified, open, flow-through chamber technique. When comparing total emissions of nitrous oxide (N₂O) and methane (CH₄), the green/food waste mixture produced 110?kg CO₂ eq./ton DM (dry matter, std error = 12.2), which were slightly lower than emissions produced by the green waste alone (152?kg CO₂ eq./ton DM, std error = 15.9). Methane was a large contributor to global warming potential (GWP) of both composting treatments, suggesting that management practices that optimize porosity and air flow in compost piles are promising in reducing emissions from both green waste and green/food waste mixtures.     

Kinetics and economics of anaerobic digestion of animal waste

Disposal of animal waste represents a severe environmental problem, particularly in areas such as cattle feedlots where livestock are concentrated. Animal waste can be converted to CO₂ and CH₄ by the autocatalytic process of anaerobic fermentation. A scheme, based upon this process, for the disposal of the waste from a large feedlot is presented. The design of this process is based on kinetic data from the literature which are fitted to a kinetic model including diffusional resistances. Sale of the CH₄ provides an economic incentive for this process and a return on investment of 23 % yr^?1 appears possible for a large feedlot.     

Managing contaminated sediments

Remediation techniques on contaminated sediments are generally much more limited than for most other solid waste materials, except for mine wastes. The widely diverse contamination sources in larger catchment areas usually produce a complex mixture of contaminants that is more difficult to treat than an industrial waste. In the first two chapters, additional information will be presented onin- situ treatment methods, which were the central topic in the Spittelwasser Case Study (JSS - Journal of Soils and Sediments, Vol. 1, No. 3, pp. 181–187), and on the development of ecologically sound dredging and processing techniques, where practical applicability had to be demonstrated as part of an integrated remediation chain. In the latter respect, mechanical separation of less strongly contaminated fractions may be a useful step prior to the final storage of the residues (chapter 2, Treatment of Strongly Contaminated Dredged Materials) For most sediments from maintenance dredging, there are more arguments in favor of ‘disposal’ rather than ‘treatment’ (chapter 3, Subaqueous Storage and Capping). Consideration about the comparative assessment of the two basic management options ofin- situ capping and dredging followed by sub-aqueous disposal are discussed on a legislative, economic and technical-environmental basis. The concept of capping of contaminated sedimentsin- situ has been developed in the last two decades as an ecologically sound and economic alternative to more costly remediation techniques. The main characteristics are related to the passive character of this concept, which minimizes labor and process costs. Mechanisms of contaminant retention in sediment caps is discussed with special regard to the chemical isolation component. From this consideration, the development of the active barrier concept is derived that denotes the use of reactive additives in capping layers to chemically bind one or more contaminants specifically.     

发达国家畜禽废物处理技术与立法

源于集约化畜禽养殖场的大量粪便及废水导致的环境污染问题越来越受到人们的关注,发达国家十分重视畜禽废物的处理技术研究及控制由其引起污染的立法工作。该文在分析畜禽废物管理系统的构成、约束及目标基础上,对发达国家近年来处理技术的发展进行综述,包括还田利用、好氧与厌氧生物处理、存贮、收集与运输、提取新产品及优化模型与决策支持系统等方面,最后对有关畜禽废物管理方面的法规做了介绍。     

Recultivation of mining waste dumps in the Ruhr area,Germany

In 1993, Ruhrkohle AG produced 41,9 million tons of coal and 19,1 million m³ of mining waste. Of this, 0,7 million m³ were used underground as stowing material, 4,7 million m³ was used commercially, while the remaining 13,7 million m³ required dumping. Efforts related to the use and disposal of the material up to now dumped are concentrating on applying technical methods to reduce the production of waste underground, on opening up new markets of this material, on utilization of mining waste as a building material, and on low-environmental-impact dumping. Since the late 1970ies, the mining waste heaps in the Ruhr mining region have been conceived and designed as “landscape structures”, i.e., they are integrated into the landscape by means of careful planning and design, and are immediately planted with vegetation.