从制碱二次盐泥废渣中提取特种碳酸钙的研究

从制碱二次盐泥废渣中提取特种碳酸钙的研究胡云霞（山东建材学院）刘惠凤（山东海化集团）中图分类号Ｘ７８１引言制碱过程中，需要净化盐水。盐水净化时产生的钙、镁等的沉淀就是盐泥。镁的沉淀称为一次盐泥，其主要成分是Ｍｇ（ＯＨ）２，钙的沉淀称为二次盐泥，其主要...

芬兰矿业的废渣和废水的处理

本文简介芬兰矿山废弃物的处理及其技术，使其危害降至最低。

Investigation and analysis of hazardous waste in the Three Gorges Area of Chongqing region

This article describes the investigation of hazardous waste (HW) in the Three Gorges Area of Chongqing region, which indicates that by May 2002, the dumped HW therein amounted to 14 600 t and was mainly distributed in five districts and counties with 11 000 t in Fuling, 1 650 t in Fengdu, 950 t in Wanzhou; 630 t in Wushan and 430 t in Yunyang. The total amount was composed of 9 670 t chromic residue, 2 310 t waste oil and residue, 410 t waste (false) fertilizer, 28 t waste chemical medicine, 26 t waste materials and 2 200 t other things including acid residue, waste asbestos, fluorine silicate, pigment, additive, waste acid, alkali, nitric acid, vitriol, lead mud, storage battery, calcium carbide, potassium cyanide, polluted soil, discard dynamite, waste packing barrel of cyanides, etc. In all of the HW, 578 t can be treated by chemical neutralization and stabilization technology such as redox, chemical precipitation, acid and alkali neutralization, etc., and the rest is temporarily untreatble and should be removed and piled at a temporary storage site above the 177 m water level of the dam with an aim to be transported to a future disposal site for innocuous treatment.

Facilities Management Carbon Footprints： An Audit of Critical Elements of Management and Reporting

Concern for the environmental impact of organizations＇ activities has led to the recognition and demand for organizations to manage and report on their carbon footprint. However, there is no limit as to the areas of carbon footprints required in such annual environmental reports. To deliver improvements in the quality of carbon footprint management and reporting, there is a need to identify the main elements of carbon footprint strategy that can be endorsed, supported and encouraged by facility managers. The study investigates carbon footprint elements managed and reported upon by facility manager in the UK. Drawing on a questionnaire survey of 256 facility managers in the UK, the key elements of carbon footprints identified in carbon footprint reports are examined. The findings indicate that the main elements are building energy consumption, waste disposal and water consumption. Business travel in terms of using public transport, air travel and company cars are also recognized as important targets and objectives for the carbon footprint strategy of several FM （facilities management） organizations.

A Review of Chemical Industry Wastewater Treatment

With the development of China＇ s industry, the domestic industrial parks greatly emerge and thus give rise to the diversity of pollutants in chemical wastewater. In this paper, the main sources of China＇ s chemical industry wastewater, main pollutants types and the wastewater characteristics of the chemical industry＇ s different branches are introduced, the related technologies and methods mainly applied to chemical industry wastewater treatment at home and abroad are analyzed and the application of different chemical wastewater treatment process is explained, and also all sorts of treatment technologies, methods, and processes are reviewed, and finally the study achievements and problems of all technol^ogies are concluded.

Comparative Study on the E-waste Recycling Systems in Japan and China

This study aims to identify processes, current situations and issues of recycling systems for four home appliances, namely, air conditioners, television receivers, refrigerators, and washing machines, among e-wastes in China and Japan for understanding and comparison of their characteristics. In accordance with results of a literature search, review of information disclosed online, and questionnaire survey conducted, the findings of this study are summarized in the following two points： （1） The results show that in Japan most of the home appliances mentioned above have been collected through home appliance recycling tickets, resulting in an issue of ＂requiring some effort＂ in treatment and recycling stages, and most plants have contracted out their e-waste recycling; （2） It is found out that advantages of the recycling system in Japan include easiness to monitor concrete data and thorough environmental friendliness ensured while its disadvantages include illegal dumping and export. It becomes apparent that advantages of the recycling system in China include a high reuse rate, low treatment cost, and fewer illegal dumping while its disadvantages include less safe reused products, environmental pollution caused by e-waste treatment, illegal import and difficulty in obtaining data.

The Use of Ground Penetrating Radar in Municipal Solid Waste Landfill Geotechnical Investigation

The use of GPR （ground penetrating radar） as an auxiliary tool in geotechnical and environmental site investigations has increased in Brazil during the past few years. GPR has been used to delineate contamination plumes, to aid in geological modelling, to detect buried structures and in archaeological surveys. This paper describes and discusses the results ofa GPR site investigation carried out at Gramacho Municipal Solid Waste Landfill in the State of Rio de Janeiro, Brazil. A field study was conducted to detect failure surfaces in its slopes and within the waste mass. The results have shown that： （l） Slip surfaces could be indicated by small continuous voids within the waste mass since there is a good contrast between the dielectric constant of air and municipal waste; （2） Greenhouse gases pools could also be indicated by large voids within the waste mass since there is a good contrast between the dielectric constant of carbon dioxide, methane and municipal waste; （3） Leachate pools present a high electric conductivity that could be easily detected by GPR.

Soil Contamination due to Activities： A Review with E-Waste Disposal and Recycling Special Focus on China

This paper presents a review of soil contamination resulting from e-waste recycling activities, with a special focus on China, where many data have been collected for a decade. Soils in the e-waste areas are often contaminated by heavy metals and organic compounds, mainly polycyclic aromatic hydrocarbons （PAHs）, polybrominated diphenyl ethers （PBDEs）, polychlorinated and polybrominated biphenyls （PCBs and PBBs）, dechlorane plus （DP）, hexabromocyclododecanes （HBCDs）, polychlorinated and polybrominated dibenzo- p-dioxins （PCDDs and PBDDs）, and polychlorinated and polybrominated dibenzofurans （PCDFs and PBDFs）, while other compounds, not systematically monitored, can be found as well. Pollutants are generally present in mixtures, so pollution situations are complex and diversified with a gradient of contamination from agricultural soils to hot spots at e-waste sites and mainly in open burning areas. It has been proved that pollutants were transferred to the food chain via rice in China, and that the population was threatened since high levels of various pollutants were detected in blood, placentas, hair, etc., of residents of e-waste sites. Eventually, soil remediation techniques are reviewed. Although there are many available techniques devoted to heavy metals and persistent organic pollutants, the current techniques for the e-waste sites, where these contaminants coexist, are very sparse. Phytoremediation has been investigated and co-cropping appears as a promising approach for the slightly contaminated agricultural soils. In some cases, different remediation techniques should be combined or trained, while the influence of coexisting contaminants and the removal sequence of contaminants should be considered. In hot spots, physical and chemical techniques should be used to reduce high pollution levels to prevent further pollutant dissemination. This review highlights the urgent needs for 1） characterization of pollution status in all the countries where e-wastes are recycled, 2） research on fate and toxicity of pollutant mixtures, and 3） development of combined techniques and strategies to remediate agricultural fields and hot spots of pollution.

Intensive photocatalytic activity enhancement of Bi5O7I via coupling with band structure and content adjustable BiOBrxI1-x

Band structure and component content are the key factors for determining the activity of semiconductor heterojunction. In this study, a novel Bi5O7I/BiOBrxI1-x heterostructure was synthesized by a simple hydrobromic （HBr） acid etching method through transforming partial of Bi5O7I to I ion doped BiOBr （BiOBrxI1-x） at room temperature without adding extra dopant. Both the band structure and component content of Bi5O7I/BiOBrxI1-x alter with the additive HBr acid. The Bi5O7I/BiOBrxI1-x （S3.0） sample exhibits the best photocatalytic activity, 6 times higher than that of pure Bis071, for the degradation of methyl orange under visible-light （2 〉 420 nm）. The activity enhancement of Bi5O7I/BiOBrxI1-x is primarily ascribed to the improved separation efficiency of photocharges, originated from the adjustable band structure and component content, The significant findings of this paper provide a facile way to construct highly efficient semiconductor heterojunction via playing the synergetic effect of adjustable band struc- ture and component content for purifying organic pollutants in wastewater.