Companies’ E-waste Estimation Based on General Equilibrium The­ory Context and Random Forest Regression Algorithm in Cameroon: Case Study of SMEs Implementing ISO 14001:2015

Given the challenge of estimating or calculating quantities of waste electrical and electronic equipment(WEEE)in developing countries,this article focuses on predicting the WEEE generated by Cameroonian small and medium enterprises(SMEs)that are engaged in ISO 14001:2015 initiatives and consume electrical and electronic equipment(EEE)to enhance their performance and profitability.The methodology employed an exploratory approach involving the application of general equilibrium theory(GET)to contextualize the study and generate relevant parameters for deploying the random forest regression learning algorithm for predictions.Machine learning was applied to 80%of the samples for training,while simulation was conducted on the remaining 20%of samples based on quantities of EEE utilized over a specific period,utilization rates,repair rates,and average lifespans.The results demonstrate that the model’s predicted values are significantly close to the actual quantities of generated WEEE,and the model’s performance was evaluated using the mean squared error(MSE)and yielding satisfactory results.Based on this model,both companies and stakeholders can set realistic objectives for managing companies’WEEE,fostering sustainable socio-environmental practices.

Electrical and Electronic Waste in Northwest Mexico

The waste derived from Electrical and Electronic Equipment (WEEE) is of interest now worldwide, in some countries due to the rapid technological development and in others due to technological dependence through the acquisition of second hand equipment. Therefore it is necessary to implement strategies for the sustainable management of electrical and electronic equipment at the end of its useful life. This paper presents the results of an investigation that was conducted in a city located in the Northwest of Mexico, which seeks to understand the management practices of household WEEE generators. A survey was applied to a representative sample of the population with a confidence level of 90%. Six home appliances were quantified and it was found that approximately 21% of them are disposed directly as part of the household flow of Municipal Solid Waste (MSW), while 79% are storage for a latter sale, repair or reuse. The results obtained support the need to develop evaluations and to implement possible scenarios for the sustainable management of Electrical and Electronic Waste.

Contamination and Remediation of Heavy Metals in Soils near E-waste Recycling Area

In order to assess heavy metals pollution in agricultural soil after renovation in typical e-waste recycling areas, 212 soil samples were col- lected and the mass fractions of 7 kinds of heavy metals （Cd, Cr, Cu, Hg, Ni, Pb and Zn） were analyzed. The results indicated that heavy metals pollution in agricultural soil was commonly existed in the study areas, and the soil was slightly contaminated by Pb but was moderately or critically polluted by Cd and Cu. However, the carcinogenic risk and non-carcinogenic risk status by heavy metals pollution were beyond acceptable levels, and soil remediation was quite necessary. After some investigations of bioremediation, we found that saponin as washing agent could highly strenqthen the behavior of heavy metals desorption from soil ,which had a good prospect of engineering practice.

Comparative studies on hydrometallurgical treatment of smelted low-grade electronic scraps for selective copper recovery

A comparison of three hydrometallurgical methods for selective recovery of copper from low-grade electric and electronic wastes was reported. Scraps were smelted to produce Cu？Zn？Sn？Ag alloy. Multiphase material was analyzed by SEM？EDS and XRD. The alloy was dissolved anodically with simultaneous metal electrodeposition using ammoniacal and sulfuric acid solutions or leached in ammonia？ammonium sulfate solution and then copper electrowinning was carried out. This resulted in the separation of metals, where lead, silver and tin accumulated mainly in the slimes, while copper was transferred to the electrolyte and then recovered on the cathode. The best conditions of the alloy treatment were obtained in the sulfuric acid, where the final product was metal of high purity （99% Cu） at the current efficiency of 90%. Ammoniacal leaching of the alloy led to the accumulation of copper ions in the electrolyte and further metal electrowinning, but the rate of the spontaneous dissolution was low. Anodic dissolution of the alloy in the ammonia？ammonium sulfate solution led to the unfavorable distribution of metals among the slime, electrolyte and cathodic deposit.

Managing economic and social profit of cooperative models in three-echelon reverse supply chain for waste electrical and electronic equipment

In addition to maximizing economic benefits, reverse supply chains should further seek to maximize social benefits by increasing the quantity of waste electrical and electronic equipment （WEEE）. The paper investigates cooperative models with different parties in a three-echelon reverse supply chain for WEEE consisting of a single collector, a single remanufacturer, and two retailers based on complete information. In acldition, the optimal decisions of four cooperative models and the effect of the market demand of remanufactured WEEE products and the market share of two retailers on the optimal decisions are discussed. The results indicate that optimal total channel profit and recycle quantity in a reverse supply chain are maximized in a centralized model. The optimal total channel profit and recycle quantity increase with an increase in the market demand of remanufactured WEEE products. The three-echelon reverse supply chain consisting of duopolistic retailers maximizes total channel profit and recycle quantity in a reverse supply chain fbr WEEE.

Recovery of Metals from Anodic Dissolution Slime of Waste from Electric and Electronic Equipment（WEEE） by Extraction in Ionic Liquids

The recovery of metals from a multi-component alloy obtained by crushing, melting and anodic dissolution of waste from electric and electronic equipment（WEEE） was investigated. The anodic dissolution of the alloy was carried out in an electrolysis cell with one copper cathode and a central cast anode, immersed in the electrolyte formed by choline chloride-ethylene glycol-iodine. The temperature of the electrolyte during the process was 343 K. Depending on the electrolysis parameters（current density and cell voltage）, cathodic deposits of Sn, Pb and Zn of 〉99% purity were obtained. Cyclic voltammetry was used in order to determine the deposition potentials of the studied metals. The obtained metallic deposits were subject of determination of XRD, SEM/EDX and AFM in order to evidence the deposits structure and morphology. The experiments performed demonstrated the possibility of separating/selective recovery of metals from the multi-component alloy resulted from the waste from electrical and electronic equipment by anodic dissolution in ionic liquids.

多主体参与的废弃电器电子产品回收治理演化博弈研究

当前私自拆解电子垃圾的事件并不鲜见,单一的政府治理模式难以实现有效治理废弃电器电子废弃物的目标,鉴于社会共治在诸多公共问题治理的成功实践,引入社会共治理念,对政府和公众共同参与废弃电器电子废弃物治理的治理模式进行研究。基于博弈论,构建政府、回收经营者、公众三方演化博弈模型,通过求解平衡点并分析平衡点的稳定状态,得出达到稳定点的稳定策略,并进行数值仿真分析参数变化对稳定策略的影响,据此给出强化企业声誉意识、完善奖惩机制、搭建便捷渠道降低公众成本等相关治理建议。

基于P640的船舶电气设备控制箱典型发热故障诊断及分析

简要介绍了P640红外热像仪的组成、温度量程,以及目前常用的红外监测诊断标准及适用范围。通过3起不同类型的电气设备异常发热故障,系统分析了故障隐患的排除方法和排除依据,总结了故障产生的原因,给出了处理建议,并就检测中遇到的问题给出了快速准确锁定异常点位置和正确判断内部缺陷的经验做法,提出评价电子元器件异常点发热的建议,对于配电箱及控制箱的电气设备检测诊断工作具有很好的指导作用和借鉴意义。

基于中等区域尺度家用电器电子产品废弃预测模型研究与实例分析

针对现有保有量废弃电器电子产品(waste electrical and electronic equipment,WEEE)预测模型的不足,给出了基于中等区域尺度下考虑梯次利用影响的WEEE预测模型,预测模型中家用电器电子产品(electrical and electronic equipment,EEE)的废弃规律采用Weilbull分布函数并按照实际修正,使得预测结果更加贴合实际。开展上海市“四机一脑”废弃量实证分析,采用现有模型验证,结果表明该WEEE预测模型可较好地预测中等区域尺度下WEEE的废弃量,为WEEE后续管理提供科学依据。

智能网联技术下机载电子电气设备检测系统设计

机载电子电气设备检测容易受到外界干扰,出现参数辨识不精准,导致检测结果不精准的情况。针对该问题,在智能网联技术下设计机载电子电气设备检测系统。使用嵌入式检测适配器,对输出信号进行放大、隔离、变换处理。结合防错插设计方式,确保检测装置安全连接。利用光耦合器实现信号的驱动与变换,使用智能网联技术聚集特征向量构建密度函数,获取聚类同期运行的峰值参数。归一化处理智能网联聚类参数,计算实际与理论辨识参数之间的差值,以此为依据判断设备运行状态。以报文ID数据标识为特征,计算时间窗口为1的信息熵值,实现固定时间窗口下的设备检测。由实验结果可知,该系统在三种场景下与实际熵值的最大误差为1.2,说明使用该系统检测结果较精准。

Bromination of Pd Compounds during Thermal Decomposition of Tetrabromobisphenol A

We conducted thermal tests using the reagent tetrabromobisphenol A (TBBPA) and various Pd compounds to study the chemical forms of Pd obtained during the pyrolytic and oxidative decomposition of TBBPA. Thermal testing was conducted in an electric furnace at temperatures of 280°C - 800°C in an Ar or Ar-O2 (5%) atmosphere for a heating period of 40 min. Scanning electron microscopy-energy dispersive X-ray spectroscopy results revealed that Pd bromide was formed in the mixture of TBBPA and PdO after heating to 450°C in the Ar atmosphere. In addition, thermogravimetry-differential thermal analysis showed that as the heating temperature was increased from 350°C to 730°C, weight loss occurred at a nearly constant rate, indicating that Pd bromide decomposed in this temperature range.

Importance of Life Cycle Analysis of the Printed Circuit Board Computer

It is estimated that there is a generation of 307,224 ton/year [1] of waste from electronic and electronic equipment (WEEE) in Mexico, of which 10% is recycled, 40% remains stored and 50% reaches landfills or uncontrolled dumps. In the practice, even the regulatory instruments are not consolidated and the adequate management of the use of WEEE management, so the aim of this study is an analysis of life cycle of printed circuit boards (TCI) to identify the management alternatives that represent the least impact to the environment. This assessment was carried out using software SIMAPRO to determine the environmental impact of each scenario, through the comparison of impacts and the proposed improvements to reduce it, following phases of this methodology by applying standards, ISO 14040/ISO 14044 [2], using data from the INE official reports since 2006 until 2010 which concentrate the information of the WEEE problem in Mexico. These data were pooled to carry out inventories according to the availability in the information, identifying the environmental impacts generated by processing. The conclusions of the LCA will serve to identify the stage with greater environmental impact, and thus propose ideas for improvement in order to minimize this impact.

WEEE处理商激励制造商环境自我规制的逆向供应链协调策略

针对报废的电子电器设备(WEEE)环境污染严重、拆解成本高、效率低的问题,考虑制造商和处理商均进行环境自我规制,探讨处理商向环境自我规制产生溢出效应的制造商提供成本分担契约的逆向供应链决策、协调及实施策略。研究发现,处理商如果无视制造商的环境自我规制成本改善溢出,其“敲竹杠”行为将影响制造商的规制努力以及双方的长期合作和污染减排。考虑制造商环境自我规制成本改善溢出的研究发现,再制造零部件批发价格契约无法实现逆向供应链成员利润的Pareto改进;一定条件下的成本分担契约可以双双提升制造商与处理商利润,减少单位WEEE的污染排放量;制造商并不希望处理商分担更高的规制成本,可以通过Nash均衡讨价还价控制成本分担比例。不同于再制造零部件批发价格契约,在集中决策或成本分担契约下,溢出效应增加时处理商的规制努力水平也在提高。

废旧电器电子产品可回收性评价研究

回收产品品质和回收价格是决定产品再流通性的主要因素。废旧电器电子产品可回收性评价定位于回收产品的品质鉴定和价格评估。基于成新率且面向回收现场的废旧电器电子产品可回收性评价方法包括两部分,一是基于部件鉴定法的废旧电器电子产品品质鉴定,二是基于市场比较法的回收价格评估。本文采用该方法,依据成新率范围划分产品品质等级,确定产品去向,并通过实例分析验证方法的有效性,使资源得到最大化利用。

电子设备模块电液同步盲插技术研究

为解决盲插电子设备模块插拔困难、可靠性低、冷却液泄漏危害严重等问题,设计一种新型的电子设备模块电液同步盲插技术。该技术通过引入盲插电连接器与液冷盲插水接头隔离防护、漏液监测、分级导向、电连接器浮动安装、不同品种电子设备模块防错插、插拔力分配、通电顺序逻辑控制技术,通过这些技术的综合应用提高电子设备模块盲插可靠性,并通过具体应用实例验证该技术的可行性和先进性。结果表明,所设计的电子设备模块电液同步盲插技术可以达到预期效果,具有较高的实际应用价值,优于同类型的设置。

电子电器实验室质控工作评价指标体系构建与实践

检测数据是实验室提供的最终"产品",确保检测数据结果有效性是实验室质控工作的重心.如何科学、合理、有效地开展质控活动,也是电子电器实验室共同关注的话题.本文通过客观评价与主观评价相结合的方法,构建了包括组织基本情况、内部质控情况、外部质控情况、应用及推广等具有实操性的实验室质控工作评价体系,为衡量电子电器实验室质控工作提供了一个评价方法,有利于激励引导电子电器检测行业不断提升质控工作质量,促进质控工作创新.

环境规制对企业出口行为的影响——来自欧盟WEEE指令和RoHS指令的实证分析

本文以2004年欧盟各成员国WEEE指令和RoHS指令的立法通过为准自然实验,考察欧盟环境规制对2004年之前进入欧盟电器电子产品市场的中国企业相关出口行为的影响。结果发现:欧盟双指令显著降低了样本企业向欧盟出口电器电子产品的规模,且企业的出口边际和集约边际均受到了负面冲击;样本企业中,加工贸易企业、外资企业和低劳动生产率企业受欧盟双指令的负面影响较大。机制分析发现,成本提升是欧盟双指令显著降低样本企业出口的重要途径;欧盟双指令虽然促进了企业创新,但并未因此对样本企业出口造成有利影响。另外,欧盟双指令显著降低了样本企业对欧盟电器电子产品市场的依赖程度,但企业并未表现出市场退出行为。

浅谈PLC技术在机械电气控制装置中的应用

PLC技术融合电子信息与自动化技术,进一步提升机械电气控制效果,在现代机械电气控制装置中的应用日趋广泛。与此同时,PLC技术在机械电气控制装置中的运用也存在一些问题。基于此,对PLC技术在机械电气控制装置中的应用表现进行分析,结合实际案例对PLC技术的应用优势进行探讨,旨在推动技术的更广泛运用,提升机械电气系统的自动化控制水平。

典型船用通导设备低温性能试验研究

目的建立有效的低温试验检测手段及评估方法,以保障冰区航行船舶在低温环境下的通讯导航能力。方法在国军标与船标的指导下,针对典型船用通导设备磁罗经与电子罗经,开展包括试前工作测试、–25℃低温贮存试验、–20℃低温工作试验以及附加防寒措施的系列考核试验。结果试验成功复现了低温环境下磁罗经与电子罗经的性能失效模式。磁罗经经历低温后,磁力指向稳定性大幅减弱,试验前后指向刻度最大偏差可达3.3°;电子罗经经历低温后,指向误差最大可达3.7°,电流最大增长32.8%。通过遮蔽防寒、伴热措施保温后,整个试验过程中温度趋于稳定,磁罗经与电子罗经的刻度示值变化幅度减小。结论磁罗经内部部件机械阻尼的增大以及自差校正磁棒磁力的改变是引起磁罗经定位精度率波动、定位误差变大的主要原因。电子罗经天线内部电气元件的性能改变是引起指向刻度变化的主要因素。通过采取一定的防寒保温措施,减小温度变化范围,将有利于提高磁罗经与电子罗经低温工作的稳定性。

基于电力电子技术的电气设备故障诊断研究

为实现电力系统的优化运行及电气设备的高效利用,介绍了电力电子技术的基本原理及电力电子设备的主要组成,提出一种新的故障诊断方法,包括故障检测、定位及分析步骤,通过模拟实验验证了该方法的可行性及有效性。结果表明,该方法能有效识别并定位电力电子设备故障,对电压降低、能量损失等常见故障具有良好的诊断性能,有助于提高电力系统的运行稳定性及安全性。