PVC废物及其处理技术

PVC广泛应用于工业和日常生活中，PVC废物的产生量将会在将来一段时间内持续增长，对PVC废物处理处置问题研究成为固体废物处理处置的一个方向，目前，PVC废物还缺乏系统、完善的管理手段和处理技术。本文在分析PVC废物特点其环境潜在危害特性的基础上，比较分析各种PVC废物处理技术的优势和存在的问题，及国内外在PVC废物处理处置方面的具体实践，以期探讨PVC废物的处理对策并提出今后PVC废物处理的发展趋势和研究方向。     

危险废物稳定化/固化技术的现状与发展

本文对危险废物稳定化／固化处理技术的历史、现状以及今后的发展方向进行了较为系统的论述，对该技术在处理危险废物时所存在的问题进行了探讨，认为今后药剂稳定化技术在废物处置预处理领域将会占据重要的地位。     

医疗废物处置单位运营存在的问题及对策

医疗废物污染防治是环境保护工作的重要组成部分,若医疗废物处置不当,将对水体、大气和土壤造成污染,甚至严重威胁人民群众身心健康.在“十一五”期间,中国投入了大量资金用于医疗废物处置设施建设,但大部分医疗废物处置单位的运营存在问题.介绍了医疗废物处置的背景,综合分析了问题产生的原因,提出了完善医疗废物管理的建议.     

重大疫情期间医疗废物应急处置中的问题及建议

医疗废物安全处置是阻断疫情蔓延的重要环节。重大疫情期间,由于医疗废物产生量急剧增加,常态下的医疗废物收集、转运、处置能力无法满足需要。通过分析我国医疗废物管理现状、重大疫情期间医疗废物产生特点,讨论疫情期间医疗废物应急处置存在的问题及原因,提出构建新的医疗废物处置模式、建立医疗废物应急处置制度体系、组建国家级和省级医疗废物应急机构、做好医疗废物应急处置设施备用工作等建议,为提升医疗废物应急处置能力提供参考,保障重大疫情期间医疗废物得到及时、安全处置。     

安徽加强医疗废弃物污染防治

日前 ,安徽省环保、卫生部门联合下发通知 ,要求各地针对医疗废水和医疗垃圾处理处置方面存在的问题 ,进一步加强医疗废弃物污染防治工作。通知要求 ,各级环保、卫生部门对医疗废弃物污染防治工作要加强领导 ,落实责任制 ,切实做好医疗废物的环境监督管理工作。进一步督促医疗卫生机构和医疗废物集中处置单位建立有效工作机制 ,严防因医疗废水和医疗废物处置不当造成二次污染或交叉感染。通知强调 ,各级环保部门要加强医疗废水和医疗废物处理处置设施的排放监测 ,严禁未经处理的或处理未达标的医疗废水和医疗废物排放。各医疗卫生机构直接从…     

水泥窑协同处置危险废物的研究现状及其发展

水泥窑协同处置危险废物作为一种新兴的危险废物焚烧处置技术,具有焚烧温度高、停留时间长、处理效果好、改造成本低等多项优势,应用前景广泛。简述了中国危险废物的产生及处理处置现状,介绍了水泥窑协同处置技术,综合国内外最新的水泥窑协同处置危险废物的文献,从熟料性质、水泥质量以及烟气排放等角度综述了垃圾焚烧飞灰、污染土壤、农药废物以及污泥类危险废物这4种典型危险废物在水泥窑中的协同处置情况,分析了每种危险废物在水泥窑中协同处置的可行性,提出了实际应用过程中应该注意的问题,最后提出了未来水泥窑协同处置危险废物的研究思路。     

有害废物管理技术基础构架

随着全球经济的高速发展，于其相伴生的有害废物破坏生态环境问题也日益尖锐，引起了多方面的关注。本文对有害废物管理的基本结构及相关的处理处置技术进行了简要探讨。     

放射性废物处置库顶盖毛细屏障的研究进展

放射性废物处置库工程屏障的设计对处置库中放射性废物的长期安全具有重要意义.毛细屏障作为处置库顶盖的工程屏障之一,已在国内外得到广泛的应用.阐述了放射性废物处置库顶盖毛细屏障设置的意义,对近年来毛细屏障的一些研究进展进行了分析,提出了一些尚待解决的问题.     

疫情下医疗废物的处置现状分析

2019年新冠疫情席卷全球,在疫情环境下,医疗废物大幅增多,全国各大城市纷纷出现医疗废物处置不当的现象。本文对国内外现状分析,在认知、设施、管理和监督四个方面发现存在一定的问题,通过加强教育、加大储备、完善机制和改善监管的建议,为提升医疗废物应急处置能力提供参考。     

天津市医疗废物处置规划及策略研究

以天津市医疗废物管理现状为研究对象,对处置方式进行深入探讨,分析目前分散处置和集中处置存在的缺陷,提出"区域集中处置"设想;并运用模糊决策模型理论,建立较完善的处置方式评价指标体系,应用模糊综合评价模型得出"区域集中处置"是最佳的医疗废物处置方式,同时提出了相应的区域集中处置策略.     

Treatment Technologies for Hazardous Wastes: Part 1 Treatment Alternatives for Dioxin Wastes

The 1984 Amendments to the Resource Conservation and Recovery Act (RCRA), called the Hazardous and Solid Waste Amendments, (HSWA) direct the EPA to determine if dioxin bearing wastes should be prohibited from landfills. This determination is to made by November 1986. Barring a determination by the Agency that the land disposal of dioxin wastes does not represent a threat to the environment, ot that appropriate alternative treatment technology is not available, a land disposal prohibition would go into effect at that time.¹ The purpose of this paper is to discuss the state of the art for several treatment processes for dioxin wastes that have been proposed to be used instead of land disposal for disposing of solid and liquid wastes containing dioxins.     

Treatment Technologies For Hazardous Wastes: Part IV A Review of Alternative Treatment Processes for Metal Bearing Hazardous Waste Streams

The U.S. Congress and the U.S. Environmental Protection Agency believe that treatment and recovery techniques should be given maximum priority when considering methods for managing the nation's generated hazardous waste. A prohibition for the disposal of certain categories of hazardous wastes either directly onto or into the land without being treated to an accepted degree prior to such disposal practice has been promulgated.¹ Wastes containing toxic metals and cyanide complexes have been selected as a group to be restricted. Due to the high generation rate associated with this category, a large capacity of waste treatment processing will be required. Existing and emerging treatment alternatives which are or have the potential to be employed for waste treatment of metal bearing wastes are presented in this paper.     

A review on management of chrome-tanned leather shavings: a holistic paradigm to combat the environmental issues

Raw hide/skins come to the tanners as a by-product of meat industry which is converted into value-added leather as product for fashion market. Leather manufacturing is a chemical process of natural biological matrix. It employs a huge quantity of water and inorganic and organic chemicals for processing and thereby discharges solid and liquid wastes into the environment. One of the potential solid wastes generated from leather industry is chrome-tanned leather shavings (CTLSs), and its disposal is increasingly becoming a huge challenge on disposal to tanners due to presence of heavy metal chromium. Hence, finding a sustainable solution to the CTLS disposal problem is a prime challenge for global tanners and researchers. This paper aims to the deeper review of various disposal methods on CTLS such as protein, chromium, and energy recovery processes and its utilization methodologies. Sustainable technologies have been developed to overcome CTLS solid wastes emanating from leather processing operations. Further, this review paper brings a broader classification of developed methodologies for treatment of CTLSs.     

Burning Chemical Wastes as Fuels in Cement Kilns

Hazardous wastes in the environment represent one of our most serious problems. Ever increasing quantities of toxic wastes have contaminated our land, air, and water. Lack of adequate hazardous waste disposal facilities is a critical problem. Landfilling toxic wastes is no longer considered safe. The tragedy of the Love Canal has demonstrated the need for proper hazardous waste disposal facilities. The best organic chemical waste disposal method is process incineration. Cement kilns have been used for burning toxic chemical industrial wastes in Canada, Michigan, New York, Sweden, etc. Existing cement kilns, when properly operated, can destroy most organic chemical wastes. Even the most complex chlorinated hydrocarbons, including PCB can be completely destroyed during normal cement kiln operations, with minimal emissions to the environment. Burning toxic chemical wastes in cement kilns, and other mineral industries, is mutually beneficial to both industry, who generates such wastes, and to society and government, who want to dispose properly of such wastes in a safe, environmentally acceptable manner. The added benefit of energy conservation is important, since large quantities of valuable fuel can be saved in the manufacture of cement when such techniques are employed.     

Public policy impacts on the generation and disposal of hazardous waste in New York State

A number of policies adopted by the federal government and the state have been designed to promote waste reduction or influence the choice of waste disposal technologies employed by generators of hazardous waste. Graphic analysis of smoothed time series data for hazardous wastes manifested in New York State for the period between June 1982 and February 1987 suggests that some of these policies have had the intended effects. Significant shifts in manifested waste volumes are evident that coincide with the following policy interventions: (1) increased state waste-end tax rates; (2) state and federal landfill bans; (3) federal restrictions on burning hazardous wastes and waste oils for energy recovery; and (4) changes in the federal regulatory definition of hazardous waste. Other changes in waste generation and management appear to be attributable to such factors as state and regional economic conditions and changes in instate treatment and disposal facility capacity. Analysis of the management of specific waste types supports evidence from the graphic analysis that waste generators changed from land disposal to "higher" waste handling technologies in response to several policy interventions.     

Public Policy impacts on the Generation and Disposal of Hazardous Waste in New York State

A number of policies adopted by the federal government and the states have been designed to promote waste reduction or influence the choice of waste disposal technologies employed by generators of hazardous waste. Graphic analysis of smoothed time series data for hazardous wastes manifested in New York State for the period between June 1982 and February 1987 suggests that some of these policies have had the intended effects.

Significant shifts in manifested waste volumes are evident that coincide with the following policy interventions: (1) increased state waste-end tax rates; (2) state and federal landfill bans; (3) federal restrictions on burning hazardous wastes and waste oils for energy recovery; and (4) changes in the federal regulatory definition of hazardous waste. Other changes in waste generation and management appear to be attributable to such factors as state and regional economic conditions and changes in instate treatment and disposal facility capacity. Analysis of the management of specific waste types supports evidence from the graphic analysis that waste generators changed from land disposal to “higher” waste handling technologies in response to several policy interventions.     

Medical Waste Disposal

Medical (biomedical) wastes pose numerous potential health and safety hazards. In addition to their infectious and toxic characteristics, the highly variable and inconsistent nature of medical waste streams has increased public concern about storage, treatment, transportation, and ultimate disposal.

In recent years, techniques have been developed to reduce human exposure to the toxic and infectious components of medical wastes. The most commonly used techniques include internal segregation, containment, and incineration. Other common techniques include grinding, shredding, and disinfection, e.g., autoclaving and chemical treatment followed by landfilling.

Of all the available technologies for medical waste treatment and disposal, incineration has been found to be the most effective method overall for destroying infectious and toxic material, volume reduction, and weight reduction in the medical waste stream, incineration destroys the broadest variety of medical waste constituents and can recover energy from the medical waste stream. Incineration also is an appropriate alternative to burial of human pathological remains.     

Incineration of hazardous wastes from the petroleum industry in Nigeria

Persistent hazardous wastes are produced in the recovery, processing and upgrading of crude petroleum in Nigeria. However, recent developments in environmental pollution control are drawing increasing attention to the problems of hazardous wastes. The ever-increasing need to control these wastes from the petroleum industry often compels the chemical engineer to specify methods of treatment and disposal. Present methods for disposal are becoming increasingly undesirable for a number of reasons, and incineration is being considered as an alternative. This paper reviews the extent of hazardous waste generation from the Nigerian petroleum industry and its environmental implications. It also examines the current disposal methods and the incineration technology option. The major chemical engineering concepts of the incineration process and the principles guiding their operations are discussed. The potential for the use of incineration is examined, as well as information that would aid the choice of incineration system for new applications.     

Immobilization of metal wastes by reaction with H2S in anoxic basins

Metal wastes are produced in large quantities by a number of industries. Their disposal in isolated waste deposits is certain to cause many subsequent problems, because every material will sooner or later return to the geochemical cycle. The sealing of disposal sites usually starts to leak, often within a short time after the disposal site has been filled. The contained heavy metals are leached from the waste deposit and will contaminate the soil and the groundwater. It is evident that storage as metal sulfides in a permanently anoxic environment is the only safe way to handle metal wastes. The world's largest anoxic basin, the Black Sea, can serve as a georeactor. The metal wastes are sustainably transformed into harmless and immobile solids. These are incorporated in the lifeless bottom muds, where they are stored for millions of years.     

Conversion of chromium-containing solid wastes into value-added products through a plasma-assisted aluminothermic process

Chromium-containing solid wastes have been generated by chemical and leather/tanning industries, and the management and proper disposal of the same wastes have been challenging tasks. A significant fraction of these wastes contains chromium compounds with chromium present in the hexavalent (Cr⁺⁶) form, which is hazardous to human beings, animals, and ecosystems. Since these wastes are discarded largely without proper treatments, soil and groundwater get contaminated and they can cause several health issues to human beings. Conventional methods developed to convert hazardous Cr⁶⁺ to Cr³⁺/Cr metal either generate secondary toxic wastes and unwanted by-products and/or are time-consuming processes. In this work, a plasma-assisted aluminothermic process is developed to convert the toxic waste into non-toxic products. The waste was mixed with aluminium powder and subjected to transferred arc plasma treatment in a controlled air atmosphere. Chemical analysis and Cr leachability studies of the waste material prior to plasma treatment have shown that it is highly toxic. Analysis of the products obtained from the plasma treatment showed that Cr and Fe present in the waste could be recovered as a metallic mixture as well as oxide slag, which were found to be non-toxic. Easy separation of the metallic fraction and the slag from the treated product is one of the merits of this process. Besides converting chromium-containing toxic waste to non-toxic materials, the process is rapid and recovers the metals from the waste completely.