Electrolytic manganese metal industry experience based China’s new model for cleaner production promotion

Cleaner production has long been viewed as an environmental management tool in China and many other countries. This understanding in recent years has become a major barrier that prevents CP from playing its full functions. This article introduces the approach, results and result dissemination of a project set up by the central government of China aiming at controlling the serious pollution of the electrolytic manganese metal industry. Based on experience of this project and our practical experiences of CP audits in more than 200 companies we propose a new model for CP promotion. A preliminary definition of the new model is presented.     

Effect of streambed substrate on macroinvertebrate biodiversity

Macroinvertebrates are important components of stream ecosystems, and are often used as indicator species for the assessment of river ecology. Numerous studies have shown that substrate is the primary physical environmental variable affecting the taxa richness and density of macroinvertebrates. The aim of this work is to study the effects of the characteristics of streambed substrate, such as grain size, shape, and roughness, on the composition and biodiversity of macroinvertebrates. A field experiment was done on the Juma River, a second-order mountain stream in northern China. Substrata of cobbles, hewn stones, pebbles, coarse sand, and fine sand were used to replace the original gravel and sand bed in a stretch of 30 m in length. The sampling results indicated that the macroinvertebrate assemblage is significantly affected by the grain size, porosity and interstitial dimension of the substrate, while it is rarely affected by the shape and the surface roughness of the experimental substrata. Macroinvertebrate compositions in cobbles and hewn stones were stable and changed least over time. The taxa richness and density of individuals in the substrata of cobbles, hewn stones, and pebbles are much higher than in those of the coarse sand and fine sand.     

Recovery of valuable materials from waste liquid crystal display panel

Associated with the rapid development of the information and electronic industry, liquid crystal displays (LCDs) have been increasingly sold as displays. However, during the discarding at their end-of-life stage, significant environmental hazards, impacts on health and a loss of resources may occur, if the scraps are not managed in an appropriate way. In order to improve the efficiency of the recovery of valuable materials from waste LCDs panel in an environmentally sound manner, this study presents a combined recycling technology process on the basis of manual dismantling and chemical treatment of LCDs. Three key processes of this technology have been studied, including the separation of LCD polarizing film by thermal shock method the removal of liquid crystals between the glass substrates by the ultrasonic cleaning, and the recovery of indium metal from glass by dissolution. The results show that valuable materials (e.g. indium) and harmful substances (e.g. liquid crystals) could be efficiently recovered or separated through above-mentioned combined technology. The optimal conditions are: (1) the peak temperature of thermal shock to separate polarizing film, ranges from 230 to 240 °C, where pyrolysis could be avoided; (2) the ultrasonic-assisted cleaning was most efficient at a frequency of 40 KHz (P = 40 W) and the exposure of the substrate to industrial detergents for 10 min; and (3) indium separation from glass in a mix of concentrated hydrochloric acid at 38% and nitric acid at 69% (HCl:HNO₃:H₂O = 45:5:50, volume ratio). The indium separation process was conducted with an exposure time of 30 min at a constant temperature of 60 °C.     

遥感资料在分析城市布局结构中的应用

本文介绍了应用彩红外航片，黑白航片分析呼和浩特市城市居民区、工业区、商业贸易区布局结构的技术。     

Atomic force microscopy study on the microtopography of natural organic matter and newly formed hydrous MnO2

To understand the water purification mechanism of potassium permanganate as a coagulation-aid during the preoxidation process, the microtopography of its reductive products, the newly formed hydrous manganese dioxide and the aged hydrous manganese dioxide, was investigated. The morphology of natural organic matter (NOM) adsorbed by the newly formed hydrous manganese dioxide was also compared with that of NOM alone. By using the tapping mode atomic force microscopy (AFM), the observation results show that the newly formed hydrous manganese dioxide possess a perforated sheet (with a thickness of 0–1.75 nm) as well as some spherical particle structures compared with the hydrous manganese dioxide with 2 h aging time, which demonstrated that the newly formed hydrous manganese dioxide had a large surface area and adsorption capacity. When 1 mmol/L newly formed hydrous manganese dioxide was added, the microtopography of NOM molecules shifted from a loosely dispersed pancake shape (with adsorption height of 5–8.5 nm) to a densely dispersed and uniform spherical structure. These results provide a valid proof that it is the perfect adsorption capability of the newly formed hydrous manganese dioxide that might result in the coagulation aid effect of potassium permanganate preoxidation.     

变压器风扇在不同转向下冷却器散热效果分析

结合芦花220 kV变电站主变风冷系统的改造工作,分析变压器风扇在不同转向情况下散热器散热效果。分析结果表明:电力变压器风扇采用前吹方式较后吹方式能更好的发挥散热器的散热效率,且不易积累灰尘,最大限度地缩短了运行维护周期,保证了变压器的可靠运行。     

解析在科研实验过程中易发生的事故

石油化工科研的试验研究、中试生产场所、试验原料及产品储存等存在着潜在的着火爆炸、中毒、机械伤害、触电等事故。我国＂安全第一,预防为主,综合治理＂的安全生产方针,其中要把＂预防为主＂贯穿于安全管理的始终，就是要采取切实有效的措施，事先对可能发生的事故进行预防和控制。     

Assessment of the bioaccessibility of polycyclic aromatic hydrocarbons in soils from Beijing using an in vitro test

As an important human exposure pathway of contaminants, soil ingestion is of increasing concern for assessing health risk from polycyclic aromatic hydrocarbons (PAHs) in soils. A wide range of total PAH concentrations ranging from 0.112 microg g(-1) to 27.8 microg g(-1) in soils collected from different public sites, including gas stations, roadsides, bus stops, a kindergarten, primary and middle schools, a university and residential area, was detected. In general, total PAHs concentrations in soils from traffic areas were significantly higher than that from the other sites, indicating a dominant contribution from motor vehicles. Physiologically based in vitro tests were used to evaluate the oral bioaccessibility of PAHs in surface soil under different land uses in Beijing regarding both gastric and small intestinal conditions. It was found that the oral bioaccessibility of total PAHs in small intestinal condition, ranging from 9.2% to 60.5% of total PAHs in soil, was significantly higher than gastric condition, ranging from 3.9% to 54.9%. The bioaccessibility of individual PAHs in soils generally decreased with the increasing ring number of PAHs in both gastric and small intestinal conditions. However, the ratio of bioaccessibility of individual PAHs in gastric condition to that in small intestinal condition, generally increased with increasing ring number, indicating the relatively pronounced effect of bile extract on improving bioaccessibility of PAHs with relatively high ring numbers characterized by their high K(ow) values. The observation that bile extract at a level higher than critical micelle concentration could reduce the surface tension of digestive juice substantially, which may cause PAHs to be available for intestinal absorption, calls for more careful establishment of reliable soil criteria for PAHs, especially concerning the health of children who may ingest a considerable amount of PAH-contaminated soil via outdoor hand-mouth activities.     

用声强法对油田注水泵房设备声源声功率的测量分析

通过对注水泵房设备声源声功率的测量和分析,确定每个噪声源重要性的排队次序,并识别其主要频率成分,作为噪声优化控制的基础。     

SO2排放造成的森林损失计算:以湖南省为例

SO₂排放对我国的森林生态系统造成了严重的损害,因而损失计算对于SO₂控制具有重要意义,但是目前仍缺乏有效的方法计算不同排放水平下的森林损失.本研究以硫沉降超临界负荷作为计算森林损失的参数,推导了适用于我国硫沉降导致森林损失的剂量-响应函数,并以湖南省为例,以1995为基准年,计算了2000年～2020年高中低3种SO₂排放方案下的森林损失.研究结果表明,随着今后湖南省经济和能源消费的增长,森林损失将继续增加.高排放方案下2020年SO₂排放将增长1.2倍,但森林损失增长4.3倍,边际损失高于6000元/t.在当前排放水平下对SO₂排放进行削减,边际效益达到1500元/t,因此控制SO₂具有显著的经济效益.对湖南案例的不确定性分析显示,计算方法有较高的可靠性.研究结果为区域SO₂控制策略的优化提供了支持.