电子废弃物现状与回收处理探讨

伴随着电子工业和信息高科技产业的高速发展,电子废弃物问题不可避免地摆在了我们的面前.伴随着电子废弃物的越境转移和我国成为世界"电子产品制造基地",我国也成为世界上最大的"电子废弃物处理场".介绍了我国及世界上电子废弃物的现状与处理状况,分析了电子废弃物具有的潜在环境污染性与可作为再生资源回收利用的资源性的双重特性,探讨了我国电子废弃物回收处理的循环经济之路,及其相关的政策、方法和措施等.     

我国电子废弃物环境资源成本及回收责任分担研究

目前,我国电子废弃物回收体系仍存在回收无序、回收利用行业发展困难等问题,而其症结在于电子废弃物回收体系责任分配的不合理。在定义电子废弃物环境资源成本的基础上,对比国内外电子废弃物环境资源成本分担的现状,分析了我国电子废弃物回收过程责任分担存在的问题。最后通过确定责任分担原则,提出了我国电子废弃物回收体系各相关主体的责任分担对策。     

电子废弃物的机械物理回收过程

电子产品数量及更新速度的提高,导致电子废弃物产生量的增长.电子废弃物中既含有有害成分,又含有大量可回收利用的有价值成分.在分析电子废弃物性质的基础上,阐述了电子废弃物的回收方法与过程.机械物理过程是根据电子废弃物的性质提出的一种回收有价值材料的过程.机械物理回收过程如筛选、形状分选、磁力分选和涡流分选已经在回收工业中被广泛使用.     

电子废弃物回收利用领域技术开发难点问题探讨

电子废弃物的资源化、减量化和无害化问题正日益受到人们的关注和重视。废弃电子线路板、硬质聚氨酯泡沫塑料、CRT显像管物料的回收利用已成为废旧电子产品处置中的三大难题。结合承担国家和省相关项目的进展，根据中国国情，提出了资源化、无害化处置上述三类电子废弃物的技术方案。     

国外电子废弃物资源化概述

随着信息工业的飞速发展,以及人们对电子废弃物认识的深入和环保意识的加强,电子废弃物的回收利用已逐渐成为一项新兴产业。通过分析国外发达国家对电子废弃物的环境管理、工艺技术以及回收体系状况,总结了发达国家的成功经验,对我国建立和完善电子废弃物管理体系,发展研究电子废弃物资源化技术提出对策和建议。     

我国电子废弃物的回收处理现状和管理对策

电子废弃物因其高速增长性、潜在污染性和资源性受到各国的广泛关注.我国由于对电子废弃物缺乏健全的回收体系和有效的监管,导致严重的环境污染和资源浪费.针对这一问题,论述了我国电子废弃物的来源、流向、处理处置和管理现状,借鉴国外生产者责任延伸制(EPR)的实践,从政府、生产者和消费者的责任分担角度.提出了适合我国国情的EPR体系.     

电子废弃物管理立法研究

我国是世界上最大的家用电器生产和消费国之一,如今面临着越来越严重的电子废弃物处理的压力.而我国电子废弃物管理方面还存在着思想障碍、体制障碍、机制障碍、政策障碍以及法制障碍等问题,急需立法给予解决.我国电子废弃物管理立法应当着重建立如下法律制度:电子废弃物的管理体制制度、生产者责任延伸制度、押金制度、产品成分标识制度、新鲜材料税或垃圾填埋税等税收制度、资源价格制度、电子废弃物中介组织和服务制度、电子废弃物的科技支撑和示范制度、绿色消费和绿色采购制度.     

电子废弃物回收利用体系建设初探

电子废弃物是目前世界上增长最快的固体废弃物之一，其不合理处置会造成人体健康危害和环境污染，作为一种潜在可回收利用的二次资源，正日益引起人们的高度关注。概述了当前世界上一些发达国家电子废弃物回收利用体系现状，分析了我国目前的相关情况，提出了建设电子废弃物综合回收利用体系对于构建循环经济和和谐社会的必要性与重要性。     

试论电信企业在ICT电子废弃物循环利用中的作用

电子废弃物回收再利用是发展循环经济的重要抓手。针对ICT(Information and CommunicationTechnology,信息和通信技术)行业发展带来日益严峻的电子废弃物问题,剖析了现有电子废弃物的回收再利用体系存在的弊端,在解读现有法律法规政策的基础上,提出优化原有体系的设想,即充分认识电信企业"管家式"运营特点有利于低成本高效率地实现电子废弃物回收再利用,电信企业介入的回收再利用模式是政府、企业与社会多赢的模式,在当前可通过签订环境合同,实现政府与电信企业的合作。     

“双碳”背景下电子废弃物全生命周期评价与管理对策

日益增长的电子废弃物具有高污染性和高附加值的双重属性,在“双碳”背景下高效回收利用电子废弃物成为我国必须面临的环境管理问题。从电子废弃物的基本特征分析入手,对回收、运输、储存和再生利用环节当前面临的现状与困境进行了剖析。并围绕“碳中和、碳达峰”的目标,提出通过发展基于大数据的全生命周期管理体系强化监督,加强回收体系建设构筑社会化回收网络,发展绿色低碳技术提高资源化综合利用率,通过技术的有效融合,推进电子废弃物资源循环产业化,建立健全绿色低碳循环发展经济体系。     

浅议碳排放与废钢铁的节能减排功效

二氧化碳是导致全球气候变暖、人类生存环境恶化的主要原因。简要介绍世界钢铁工业二氧化碳排放情况,针对我国钢铁工业碳排放的具体情况,提出发展我国废钢产业,提高废钢铁的供应能力,是我国钢铁工业摆脱危机,实现低碳发展、绿色发展的主要途径。     

Synthesis and identification of graft copolymers of wood pulp and styrene

Based on the graft copolymerization reactions of lignin and vinyl monomers, a series of graft copolymers of wood pulp and styrene (1-phenylethene) has been synthesized. The wood pulps used in this research are unbleached products produced by chemical, thermal, and mechanical pulping. All of them contain a high content of lignin (25–29 wt%). The grafting reaction is a free radical polymerization coinitiated by calcium chloride, hydrogen peroxide, and wood pulp in dimethylsulfoxide at 30°C. The effect of reaction temperature, reaction time, and the amount of the reactants on the conversion of monomer, yield of product, weight increase of pulp, and grafting efficiency of monomer has been studied. The grafted wood pulp was separated from homopolystyrene formed during the reaction by extraction of the reaction product with benzene in a Soxhlet apparatus for at least 48 h. The results show that after the reaction, the weight of all wood pulps was significantly increased and the weight increase of very high yield sodium bisulfite pulp (VHYS) was 333%. This proves that a part of the polymerized styrene was chemically bound to the wood pulp. The Fourier transform infrared (FTIR) spectra of the extracted products show absorbance peaks characteristic of both wood and polystyrene and, thus, provide strong proof of grafting. Grafting has completely changed the surface properties of the starting wood pulp from hydrophilic to hydrophobic, and under ordinary thermal compression conditions, thermoplastic composite objects of good uniformity can be made directly from reaction products which contain up to 52 wt% wood pulp.     

Fate and effect of linuron and metribuzin on the co-composting of green waste and sewage sludge

The fate and effect of the herbicides linuron and metribuzin on the co-composting of sewage sludge and green waste were addressed in this work. The experiments were conducted in metal cubic containers of 1.0 m³ volume simulating a windrow composting system. A mixture of sludge and green waste was prepared at a ratio of 1:5 v/v. The mixture was split in four equal parts and the two herbicides were added, using a pressure sprayer, as sole or mixed pollutant in each of the three mixtures. The forth mixture was composted without any addition of herbicide, to serve as control. Temperature, physicochemical characteristics, herbicide concentration, carbon dioxide emission, methane emission and microbiological parameters were measured either daily or every time the mixtures were turned, for a period of 80 days. Both herbicides’ concentration decreased significantly resulting in removal efficiencies of 99.1–99.7% and 95.8–96.0% for linuron and metribuzin, respectively. Incubation of microbiologically inactive mixtures at a temperature schedule following the spontaneous temperature evolution in the composters resulted in very little (1–11%) decomposition for both herbicides. Comparison of the variation of physicochemical parameters and microbial populations during composting indicated that both herbicides did not affect the composting process.     

资源循环科学与工程专业课程体系优化与教学内容创新实践的探索

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。     

Photo-oxidation and Photo-toxicity of Crude and Refined Oils

The fate and effects of an oil spill are effected by solar radiation through the action of photo-oxidation and photo-toxicity. Photo-oxidation, an important process in the weathering of oil, produces a variety of oxidized compounds, including aliphatic and aromatic ketones, aldehydes, carboxylic acids, fatty acids, esters, epoxides, sulfoxides, sulfones, phenols, anhydrides, quinones and aliphatic and aromatic alcohols. Some of these compounds contribute to the marine biota toxicity observed after an oil spill. Photo-toxicity occurs when uptake of certain petroleum compounds, e.g. certain polycyclic aromatic hydrocarbons and benzothiophenes, is followed by solar exposure which results in much greater toxicity than after dark uptake. The mechanism of PAH photo-toxicity includes absorbance of solar radiation by the PAH which produces a free radical and this free radical in turn reacts with oxygen to produce reactive oxygen species that can damage DNA and other cellular macromolecules. While most studies on photo-toxicity have been carried out in the laboratory, there are studies showing that water from an oil spill is photo-toxic to bivalve embryos for at least a few days after the spill. Other studies have found that oil contaminated sediments are photo-toxic to several marine invertebrates. More studies are required to determine if marine fauna at an oil spill site are effected by the action of photo-toxicity and photo-oxidation.     

我国废旧电子电器产品拆解技术、设备应用现状及改进建议

从我国废旧电子电器回收行业基本情况、专业技术人才情况、相关企业拆解技术设备情况等方面，阐述了我国废旧电子电器产品拆解技术、设备应用现状，并提出相关改进提升建议。     

TEMPO-Mediated Oxidation of Norway Spruce and Eucalyptus Pulps: Preparation and Characterization of Nanofibers and Nanofiber Dispersions

This study deals with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation of cellulose. Softwood and hardwood pulp fibers were suspended in water and oxidized to various extents at pH 10 and 22 °C using sodium hypochlorite in the presence of TEMPO radical and sodium bromide. This reaction system is known to be the most efficient one for the introduction of both surface carboxyl and aldehyde groups. Important relationships between formation of these functional groups and the fibrillation yield, light transmittance of the water dispersions and degree of polymerization of the oxidized softwood and hardwood pulps were established in the present study. A birefringence test confirmed the presence of nanofibers which according to atomic force microscopy analyses had diameters in the 1.6–3.8 nm range.     

炼油废水处理的现状、问题及对策

针对原油性质日趋恶劣、排放标准日益严格的形势,介绍了炼油废水的处理现状,分析了炼油废水在达标排放、处理回用、运行成本等方面面临的主要问题,提出了从源头挖掘节水减排潜力、实施装置排水分级控制与高浓度废水预处理、对废水处理场进行适度改造和补充完善、开发含盐废水处理技术等对策。     

火电厂灰渣浸溶特性及冲灰过程中铬、铅的迁移转化规律研究

通过对电厂除灰系统结构、冲灰用水种类、灰水比的调查，对除尘器下干灰进行标准和模拟浸溶试验，研究灰渣浸溶特性和六价铬、铅在冲灰过程中的迁移转化规律，从而为进一步开展重金属污染防治和减小灰场灰水对周围环境的影响提供理论依据。     

Laboratory Experiments and Estimation of Cumulative Infiltration and Sorptivity

Soil water cumulative infiltration affects the environment by controlling the irrigation rate and consequently the water and pollutants movement through the ground. In order to study the cumulative infiltration in a sandy soil sample, experiments were performed in the laboratory. The sample was placed uniformly in a transparent column with an inner diameter of 6 cm. A constant head boundary condition of a 2 mm height was applied on the surface of the sample and the cumulative volume of the incoming water was measured. Soil moisture at four locations of the column was measured, by using the TDR method in order to obtain the moisture profiles. By comparing the values of the infiltrated water volumes with those calculated by the integration of the moisture profiles, a good agreement was found out. Also the Parlange theoretical model fitted very well with the infiltration experimental points.