Numerical simulation of the large-scale malignant environmental pollution incident

With the development of economy, the expansion in industrial production resulted in the increase in the number of malignant environmental pollution incidents. The dispersion of toxic gaseous materials was chosen for study in detail, which took the ‘12.23’ Kaixian blowout accident in Chongqing as an example. This paper firstly reviewed the ‘12.23’ Kaixian blowout accident. Then, the physical boundary conditions including initial conditions were outlined to form an integrated mathematical problem. Thirdly, the blowout accident was simulated for a period of 5 h. In term of criteria for acute poisoning, simulation results were analyzed using the concentration slices that can serve for the decision-making. Finally, based on the analysis of simulation result, four important conclusions were put forward that can be used for the design of emergency evacuation routes.     

复杂山区地形高含硫气井安全防护距离研究

通过对国内某重大高含硫井喷事故进行调查,采用大涡模拟方法对3口井井喷气体扩散进行模拟,计算不同风速风向在事故中造成的灾难后果,得出地形因素对于灾难的影响。通过计算不同浓度下的扩散距离,提出分析及计算安全防护距离的方法。根据计算结果的综合分析可以看到,其浓度扩散的最远距离位于带状分布以内。     

Solubility of organic acids in various methanol and salt concentrations: the implication on organic acid sorption in a cosolvent system

The well-known cosolvency-induced sorption model is not applicable to predict the sorption of carboxylic acids in cosolvent system. To investigate the phenomenon, sorption and solubility of chlorinated phenols (2,4-dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP)) and carboxylic acids (benzoic acid and 2,4-dichlorophenoxyacetic acid (2,4-D)) were measured in soil-methanol mixture with various ionic strengths. The sorption (K_m) of chlorinated phenols was explained by a cosolvency-induced sorption model; the inverse log-linear relationship between the K_m and methanol volume fraction (f_c). However, the K_m of carboxylic acids increased with increasing f_c. This discrepancy was attributed to the effect of the carboxylic moiety. To explain the effect, solubility was measured for benzoic acid and 2,4,6-TCP from various liquid conditions. For both solutes, the cosolvency power (σ) increased with CaCl₂ concentrations and the salting constant (K^s) became smaller as f_c increased. However, the σ value at a given salt concentration and the K^s value at a given f_c were greater for 2,4,6-TCP than for benzoic acid, both of which were due to the greater hydrophobicity of the former. Overall, the solubility profiles of the both solutes on combination of f_c and CaCl₂ concentration evidenced no specific role of the carboxylic moiety. Therefore, it can be reasonably concluded that the positive relationship between K_m and f_c for carboxylic organic acid can be attributed to the modification of the activity coefficient occurred in the solid phase, which cannot be traceable by cosolvency-based model.     

Quality control for sampling of PCDD/PCDF emissions from open combustion sources

Both long duration (>6 h) and high temperature (up to 139 °C) sampling efforts were conducted using ambient air sampling methods to determine if either high volume throughput or higher than ambient air sampling temperatures resulted in loss of target polychlorinated dibenzodioxins/dibenzofurans (PCDDs/PCDFs) from a polyurethane foam (PUF) sorbent. Emissions from open burning of simulated military forward operating base waste were sampled using EPA Method TO-9A for 185 min duration using a filter/PUF/PUF in series combination. After a 54 m³ sample was collected, the sampler was removed from the combustion source and the second PUF was replaced with a fresh, clean PUF. An additional 6 h of ambient air sampling (171 m³) was conducted and the second PUF was analyzed to determine if the PCDD/PCDF transferred from the filter and the first PUF. Less than 4.4% of the initial PCDD/PCDF was lost to the second PUF. To assess the potential for blow off of PCDD/PCDF analytes during open air sampling, the mobility of spiked mono- to hepta-PCDD/PCDF standards across a PUF sorbent was evaluated from ambient air temperatures to 145 °C with total volumes between 600 L and 2400 L. Lower molecular weight compounds and higher flow amounts increased release of the spiked standards consistent with vapor pressure values. At 600 L total sampled volume, the release temperature for 1% of the tetra-CDD (the lowest chlorinated homologue with a toxic compound) was 87 °C; increasing the volume fourfold reduced this temperature to 73 °C.     

环境工艺方法论研究——取长补短法

取长补短法是哲学意义上的一类非常重要的方法。本文论述了取长补短法的定义,列举了此法在环境工艺中的成果,并对其哲学内涵进行了探讨。     

运用首次全国污染源普查结果 指导制定县域低碳经济发展规划

本文阐述了依据首次全国污染源普查成果,指导县域低碳经济建设规划制定的基本理念和方法。     

选矿浮选电机烧坏原因分析

分析了浮选电机烧坏的原因,提出了防止电机烧坏的措施。     

邯钢炼铁系统粉尘污染防治技术分析

重点介绍了邯钢新建2000m^3高炉（7^#高炉）出铁场和槽下上料系统粉尘污染治理方面的成功经验，并对应用电除尘器处理粉尘的技术进行了简要分析。     

灰色关联分析在地下采空区危险度评价中的应用

首先介绍了灰色关联分析的基本思想和分析步骤，在找出影响采空区危险度的主要因素之后，确定各因素指标的权重，用灰色关联分析方法求出因素的关联度。最后通过实例分析，说明了该方法在评价采空区危险度中的科学性和有效性。     

Systematic studies of shop and leisure voucher incentives for household recycling

This work reports on a series of medium scale trials of various voucher based incentives schemes for household recycling carried out in England. They show that increases of 10–20% in participation rates can be achieved with 3-month schemes. The results are drawn from 15 sub-projects carried out in 6 districts where parameters such as voucher value, types of shops used, demographics and community types were varied overall, allowing their effects to be explored. Surprisingly, the results show that the success does not depend on the affluence of the areas. Statistically strong data shows little difference across deprivation indices. Successful schemes were those where the vouchers were awarded on an individual household basis (very important), the value of each voucher was over £1 (€0.60), and the shops or facilities they are valid for were within half a mile (with suggestions from the public that if usable at supermarkets they would travel further). Although some improvements were seen in areas where participation rates were already over 65%, the schemes are more successful in areas which are not already achieving so highly, right down to those below 20%. Although schemes can be designed for maximum effect in small targeted areas, they could also be used on a large scale if e.g. supermarket vouchers were used. The study also reports on the costs of the schemes, which range from £5.15 per household to £12.10 per household over 3 months (including monitoring work). Possible savings of up to 50% are indicated.