PVC回收新方法

要从纯聚氯乙烯（ＰＶＣ）中回收ＰＶＣ很简单,但要从混合物中回收ＰＶＣ则比较麻烦。ＳｏｌｖａｙＳ．Ａ．公司开发出一种不产生废液、可从混合物中回收ＰＶＣ的方法,回收的ＰＶＣ质量与原产品质量一样。这种新方法被称作Ｖｉｎｙｌｏｏｐ法。采用该法回收ＰＶＣ时,先将混合物粉碎,然后在７０～８０℃和低压条件下用一种特殊的溶剂有选择地溶解其中的ＰＶＣ。将溶解的ＰＶＣ与其他依然为固体的混合物组分分离,再加入一种特殊的添加剂,使ＰＶＣ沉淀形成大小均匀的颗粒。溶剂可回用。Ｓｏｌｖａｙ公司已建有１套中试装置,预计２００１…     

生活垃圾分类背景下对广州市废玻璃回收利用的思考

废玻璃是一种载能节能、低碳环保、可重复利用和再生利用的再生资源,广州市通过补贴政策、两网融合等手段,促进废玻璃回收利用,随着生活垃圾分类纵深推进,为了进一步提高废玻璃回收利用,从废玻璃回收利用现状入手,对比了北京、上海生活垃圾中废弃玻璃的占比情况,针对目前存在问题,提出废玻璃回收利用分析与建议。     

从废FCC催化剂和废汽车尾气净化催化剂中回收稀土的研究进展

以稀土元素(简称稀土)用量较大的废FCC催化剂和废汽车尾气净化催化剂为研究对象,分析总结了两类废催化剂中稀土的成分和回收方法。从废催化剂中回收稀土普遍采用先浸出、后分离提纯的方法。浸出普遍采用无机酸(多为盐酸),分离方法包括溶剂萃取法、化学沉淀法等,最后经焙烧得到稀土氧化物。为从废催化剂中高效回收稀土,可着重考察新浸出机制的引入、分离方式的选择、分离试剂的应用,以及浸出和分离条件的优化,从而为实现工业化回收提供技术支持。     

废PET回收利用新方法

在欧洲和北美,聚对苯二甲酸乙二醇酯（ＰＥＴ）年回收量为４８．２万ｔ,但由于没有经济的方法将其转化成食品接触级ＰＥＴ,因此通常都是将其制成聚酯纤维或薄膜。同时,ＰＥＴ的回收利用是一种机械过程,即要根据颜色分类、粉碎和熔融。现在,Ｅａｓｔｍａｎ化学公司开发出一种回收利用方法,不仅可将废ＰＥＴ制成食品接触级及其他级的ＰＥＴ,还可避免颜色分类。该法是一种化学方法,是先将粉碎的ＰＥＴ溶解,再将其解聚成单体,可用于代替生产ＰＥＴ的新原料。现正对该法进行中试,以便为设计工业装置求取数据。回收的ＰＥＴ的费用预计…     

基于物理回收方式的线路板资源化技术改造案例分析

分析了线路板的结构及组成,对当前废线路板资源化技术进行归纳,并结合实际生产案例,介绍了一种基于物理回收方式的废线路板烘烤废气治理工艺,为脱锡工艺的尾气净化提供解决方案。     

工业废催化剂的回收利用与环境保护

大量工业废催化剂的丢弃,不仅是一种资源的浪费,而且对环境也会造成一定程度的污染,针对工业废催化剂的回收利用进行了探讨,着重介绍了几种工业废催化剂的综合回收技术.     

北京市居民PET饮料瓶的消费及回收行为研究

2010年,中国成为世界上PET饮料瓶使用量最大的国家,但中国目前缺乏正规、完整的废PET饮料瓶回收系统,导致了严重的社会与环境问题.因此,采用街头访问的方式,对北京市PET饮料瓶的回收情况展开调研.结果显示,消费后的废PET饮料瓶,44％被消费者存放在家里以卖钱,56％被消费者直接扔进垃圾桶.通过拾荒者、流动回收人员等回收者的回收行为,北京几乎所有的废PET饮料瓶都得到了回收,其中90％是由非正规的回收者回收的.回收后的废PET饮料瓶绝大部分都被小型的、非正规的、没有环境污染防治设施的小工厂使用.     

美国城市固废垃圾数据统计分类及处理方式

随着我国垃圾分类在全国范围开展,生活垃圾分类回收后,如何进行数据统计工作,不同的垃圾处理方式的统计数据采集等相关工作,已经提到议事日程。通过美国环境保护署2019年11月发布的《可持续性材料管理2017年报告》中,城市固废垃圾两种分类方法及其4种处理方式介绍,了解美国如何进行城市固废垃圾的数据统计。     

航空煤油精制工艺的产污对比及防治措施

对国内外常用的两种航空煤油（简称航煤） 精制工艺——加氢工艺和非加氢工艺进行了介绍，结合各自的工艺流程对“三废”排放情况进行了分析，并提出了相应的污染防治措施。分析结果表明：与加氢工艺相比，非加氢工艺相对简单，对反应的控制要求较低；两种工艺排放的废气和废水基本相同，包括酸性水、含油废水和酸性气等；非加氢工艺产生的废渣量远大于加氢工艺，除包括加氢工艺产生的废催化剂和废瓷球外，还包括废白土、废岩盐和废脱酸吸附剂等；航煤精制工艺的有组织排放污染物可通过酸性水汽提装置和硫磺回收装置进行处理，废渣由原生产厂家回收或按性质分类送往符合资质的相应渣场处理。     

专利名称:一种废旧轮胎热裂解设备的再冷却回收装置

正专利申请号:CN201720210679.6公开号:CN206607197U申请日:2017.03.06公开日:2017.11.03申请人:贵州火生宝再生资源有限公司本实用新型公开了一种废旧轮胎热裂解设备的再冷却回收装置,包括静态裂解釜和冷却系统,在冷却系统冷凝管道的末端上方设有连通的回收管道,该回收管道向上倾斜设     

Leaching behaviour of hazardous demolition waste

Demolition wastes are generally disposed of in unlined landfills for inert waste. However, demolition wastes are not just inert wastes. Indeed, a small fraction of demolition waste contains components that are hazardous to human health and the environment, e.g., lead-based paint, mercury-contained in fluorescent lamps, treated wood, and asbestos. The objective of this study is to evaluate the release potential of pollutants contained in these hazardous components when they are mixed with inert wastes in unlined landfills. After identification of the different building products which can contain hazardous elements and which can be potentially pollutant in landfill scenario, we performed leaching tests using three different lysimeters: one lysimeter containing only inert wastes and two lysimeters containing inert wastes mixed with hazardous demolition wastes. The leachates from these lysimeters were analysed (heavy metals, chlorides, sulphates fluoride, DOC (Dissolved Organic Carbon), phenol index, and PAH). Finally, we compared concentrations and cumulative releases of elements in leachates with the limits values of European regulation for the acceptance of inert wastes at landfill. Results indicate that limit values are exceeded for some elements. We also performed a percolation column test with only demolition hazardous wastes to evaluate the specific contribution of these wastes in the observed releases.     

Modelling the aerobic degradation of organic wastes based on slowly and rapidly degradable fractions

Several organic wastes of major production in the world (municipal solid wastes, wastewater sludge, manures and bulking agents) and some already treated organic wastes have been investigated to determine the partition among the several fractions that compose them and their kinetics of biodegradation. Different literature models have been explored for their suitability to predict the behaviour in respiration studies of these wastes. All the models presented limitations related to their simplicity or their excessive complexity, which makes them unsuitable for reliable and fast studies at real scale. A new model based on the rapid, the slowly and the inert organic fractions has been tested for all the wastes, showing excellent correlations with actual respiration activity. Finally, the kinetic parameters for this model in its application to all the wastes studied are presented.     

Medical wastes management in the south of Brazil

In developing countries, solid wastes have not received sufficient attention. In many countries, hazardous and medical wastes are still handled and disposed together with domestic wastes, thus creating a great health risk to municipal workers, the public and the environment. Medical waste management has been evaluated at the Vacacai river basin in the State of Rio Grande do Sul, Brazil. A total of 91 healthcare facilities, including hospitals (21), health centers (48) and clinical laboratories (22) were surveyed to provide information about the management, segregation, generation, storage and disposal of medical wastes. The results about management aspects indicate that practices in most healthcare facilities do not comply with the principles stated in Brazilian legislation. All facilities demonstrated a priority on segregation of infectious-biological wastes. Average generation rates of total and infectious-biological wastes in the hospitals were estimated to be 3.245 and 0.570 kg/bed-day, respectively.     

Pulp and paper plant wastes valorisation in bituminous mixes

Nowadays, the increasing amount of wastes is a concerning reality and the environmental aspects has become a major priority. Following this worry, the purpose of this experimental study was to investigate the possibility of using pulp and paper inorganic wastes, named dregs and grits, in bituminous mixtures as aggregate replacement to reduce environmental effects of these wastes disposal.First, the wastes were chemically and physically characterized and also tested primarily taking into account the requirements for aggregates in bituminous mixtures. Then, formulations were prepared replacing aggregates with wastes in different amounts. The mechanical properties of these mixtures containing wastes were compared with reference samples based on standard methods.According to the results it was possible to verify that grits had a good performance and it might be directly tested industrially as an aggregate in road construction. On the other hand, dregs need to be treated before incorporation to guarantee stable mixes in terms of water sensitivity.     

Optimization of separation and logistics for recycling materials from wallpaper hanging sites

It is of huge importance for sustainability to find a pragmatic solution for recycling of a variety of wastes emitted in small mass such as the case of wallpaper replacements. A combination of two-step sorting scheme and transportation of the wastes in collaboration with the wholesalers was proposed to enhance the efficiency of recycling. The two-step sorting consists of the first sorting at the wallpaper hanging sites to separate and group wastes in a way to avoid heavy additional burden on the hanging job. Secondary sorting is conducted at a Sorting Center to re-group wastes to send to an intermediate processing company for recycling. To minimize the costs for transportation, the grouped wastes emitted at the hanging sites are brought back by the hangers and kept temporally and then moved to the wholesaler(s) on the way to receive new materials. When the wastes at the wholesaler(s) become sufficiently large for economic transportation, a truck is arranged to collect the wastes to transport them to the Sorting Center. A feasibility study to test the practicality of the method confirmed that it could be operable and the cost would be comparable or lower than that currently incurred for disposal of the wastes.     

Accelerated carbonation treatment of industrial wastes

The disposal of industrial waste presents major logistical, financial and environmental issues. Technologies that can reduce the hazardous properties of wastes are urgently required. In the present work, a number of industrial wastes arising from the cement, metallurgical, paper, waste disposal and energy industries were treated with accelerated carbonation. In this process carbonation was effected by exposing the waste to pure carbon dioxide gas. The paper and cement wastes chemically combined with up to 25% by weight of gas. The reactivity of the wastes to carbon dioxide was controlled by their constituent minerals, and not by their elemental composition, as previously postulated. Similarly, microstructural alteration upon carbonation was primarily influenced by mineralogy. Many of the thermal wastes tested were classified as hazardous, based upon regulated metal content and pH. Treatment by accelerated carbonation reduced the leaching of certain metals, aiding the disposal of many as stable non-reactive wastes. Significant volumes of carbon dioxide were sequestrated into the accelerated carbonated treated wastes.     

Optimization of cement-based stabilization/solidification of organic-containing industrial wastes using organophilic clays

The treatment of organically contaminated industrial wastes by cement-based stabilization/solidification has, in the past, been restricted by the detrimental effect of organic compounds on cement hydration. This work investigates the use of organophilic clays as adsorbents for the organic components of industrial wastes prior to conventional cement-based solidification. Three industrial wastes containing between 2–12% organic carbon and trace heavy metal contamination were treated with a quaternary ammonium salt exchanged clay. The organic component of all three wastes was well adsorbed by the clay. Solidification of the waste/clay mixes produced a monolithic mass with adequate strength and very low leaching of either the organic compounds or the metals. This study has shown that organophilic clays can act as successful adsorbents for the organic contaminants of industrial wastes and enable them to be treated by cement-based solidification.     

An overview of metals recovery from thermal power plant solid wastes

Thermal power plants (TPPs) that burn fossil fuels emit several pollutants linked to the environmental problems of acid rain, urban ozone, and the possibility of global climate change. As coal is burned in a power plant, its noncombustible mineral content is partitioned into bottom ash, which remains in the furnace, and fly ash, which rises with flue gases. Two other by-products of coal combustion air-pollution control technologies are flue gas desulfurization (FGD) wastes and fluidized-bed combustion (FBC) wastes. This paper analyzed and summarized the generation, characteristics and application of TPP solid wastes and discussed the potential effects of such solid wastes on the environment. On this basis, a review of a number of methods for recovery of metals from TPP solid wastes was made. They usually contain a quantity of valuable metals and they are actually a secondary resource of metals. By applying mineral processing technologies and hydrometallurgical and biohydrometallurgical processes, it is possible to recover metals such as Al, Ga, Ge, Ca, Cd, Fe, Hg, Mg, Na, Ni, Pb, Ra, Th, V, Zn, etc., from TPP solid wastes. Recovery of metals from such wastes and its utilization are important not only for saving metal resources, but also for protecting the environment.     

Carbon dioxide and ammonia emissions during composting of mixed paper, yard waste and food waste

The objective of the work was to provide a method to predict CO2 and NH3 yields during composting of the biodegradable fraction of municipal solid wastes (MSW). The compostable portion of MSW was simulated using three principal biodegradable components, namely mixed paper wastes, yard wastes and food wastes. Twelve laboratory runs were carried out at thermophilic temperatures based on the principles of mixture experimental and full factorial designs. Seeded mixed paper (MXP), seeded yard waste (YW) and seeded food waste (FW), each composted individually, produced 150, 220 and 370 g CO2-C, and 2.0, 4.4 and 34 g NH3-N per dry kg of initial substrate, respectively. Several experimental runs were also carried out with different mixtures of these three substrates. The effect of seeding was insignificant during composting of food wastes and yard wastes, while seeding was necessary for composting of mixed paper. Polynomial equations were developed to predict CO2 and NH3 (in amounts of mass per dry kg of MSW) from mixtures of MSW. No interactions among components were found to be significant when predicting CO2 yields, while the interaction of food wastes and mixed paper was found to be significant when predicting NH3 yields.     

包装垃圾的分类与回收利用

包装垃圾是由废弃的包装物产生的固体垃圾,约占我国城市生活垃圾的1/3,虽然政府进行了必要回收,但仍有1/3以上的塑料、玻璃等包装物没能被有效回收利用,成了填埋场的主要填埋物,造成了环境污染和土地、石油等不可再生资源大量浪费。从回收利用和源头减量两方面提出包装垃圾的应对,一是对包装垃圾按来源、成分等进行详细分类,并建议回收处置方法;二是从制定行业政策方面来减少过度包装和扶持再生资源行业健康发展,有效处置包装垃圾等可再生资源。