七道湾污水厂污泥重金属形态特征研究

采用Tessier连续提取法对乌鲁木齐七道湾污水厂夏季和冬季污泥中的Cu、Zn、Pb、Cd进行了含量和形态分析,研究了污泥中重金属的生物有效性。结果表明:该污水厂污泥中重金属含量Zn>Cu>Pb>Cd,4种重金属含量均低于污泥农用污染物控制标准限值。Cu、Zn、Pb主要以残渣态和有机结合态形式存在,Cd主要以残渣态、铁锰氧化态和碳酸盐结合态形式存在。Zn、Cu的生物不可利用态含量高,所占比例在60%以上,对污泥农用有利,Pb、Cd两种元素的生物有效态和潜在有效态之和所占比例在50%以上,有较强的生物可利用性,在污泥农用时存在一定潜在风险。     

玻璃窑高温烟气净化工艺设计

通过分析已实施的工程运行情况,总结了玻璃窑烟气采用湿法净化系统存在的一些问题:一是高温腐蚀非常严重,二是结垢堵塞严重,再就是水处理系统的冷热水分层问题。供类似工程的方案设计参考。     

创新安全教育教学思路增强安全教育实效

在安全教育教学实践中,创新安全教育教学思路,采用互动式教育法、正反例证教育法、安全文化教育法、格言警句教育法等职工乐于接受的方式方法,对于增强安全教育效果有重要的作用。针对不同的教育对象,方法上要有所侧重。同时安全教师应选择新近、及时的安全教育内容,并不断提高自身素质。     

室内环境安全及污染控制

近年来室内装修污染健康危害事件不断发生,成为居民投诉的热点,室内环境安全也已成为学术界和政府部门关心的焦点.本文以九江地区室内环境质量状况为例,指出了室内空气污染的来源,分析了各种室内主要污染物对人体健康的影响,对如何防治室内污染,达到居住环境安全的问题进行初步的探讨.     

直缝埋弧焊管氧化铁及粉尘的吸附处理装置

为了克服氧化铁厦粉尘等杂物滞留在直缝焊管缝内,设计并制作了吸附处理装置。介绍了该装置的结构照成、装置特点厘工作流程等＋实际应用表明,这套装置吸附分离效果良好。     

压缩比和EGR对自由活塞发动机HCCI爆震燃烧的影响

基于AVL FIRE仿真平台建立了液压自由活塞发动机气缸的三维仿真模型,使用大涡模拟（large eddy simulation, LES）耦合甲醇的详细化学反应动力学机理研究了压缩比和废气再循环（exhaust gas recirculation, EGR）率对均质压燃（homogeneous charge compression ignition, HCCI）爆震燃烧过程的影响。结果表明:甲醇的HCCI燃烧需要一定的进气加热;随着压缩比的提高,最小进气温度逐渐降低,缸内的最高燃烧温度、最大爆发压力和爆震强度均明显增加;在高压缩比工况下引入EGR时可以降低爆震强度,但EGR率较小时效果并不明显,因此需要较大的EGR 率来抑制爆震;最后,对压力振荡曲线的频谱特性进行了分析,发现爆震燃烧时压力振荡的峰值频率位于10～15 kHz区间内。     

沙尘与大雾天气对京津石空气质量影响

采用北京、天津、石家庄2001-2010年沙尘与大雾天气的统计数据以及城市空气污染指数（API）,分析北京、天津、石家庄3市空气污染指数变化特征及大雾和沙尘天气下北京、天津、石家庄3市空气质量情况,进而得出沙尘大雾天气对京津石空气质量的影响。结果表明：2001-2010年间北京、天津、石家庄3市API总体呈下降趋势,天津、石家庄相对于北京空气质量改善较为明显,且空气质量夏季〉秋季〉春冬季。沙尘天气条件下,北京、天津、石家庄3市API平均值分别为255、179和167,空气质量出现良的比率天津为24%,北京、石家庄为10%左右,出现重污染的比率北京高达50%以上,天津和石家庄均在20%左右;3市沙尘天气高频次均出现在3-5月份,但北京沙尘天气发生次数远大于天津和石家庄。大雾天气条件下,北京、天津、石家庄3市API平均值为185、130和167,空气质量出现优或良的比率：天津〉石家庄〉北京,北京和石家庄出现重污染的比率均接近30%,天津不到10%,所以大雾天气对3市空气质量影响较小,大雾天气频次的变化波动并未对该地区空气质量的年际变化造成显著影响,3市高频次大雾天气集中在10-12月份,对该时段内空气污染呈现加重趋势有一定的贡献。所以沙尘和大雾天气均对北京、天津和石家庄空气质量存在不利影响,其中对北京影响最为严重,对天津影响最轻。整体上沙尘对3市的空气质量影响较大,大雾天气影响较小。     

Remediation of soil heavily polluted with polychlorinated biphenyls using a low-temperature plasma technique

Polychlorinated biphenyls （PCBs） were removed by low-temperature plasma technique （dielectric barrier discharge） from heavily polluted soil and their intermediate products were analyzed. The removal rate ranged from 40.1 to 84.6% by different treatments, and they were also influenced significantly （P 〈 0.01） by soil particle-size, electric power, gas flow rate and reaction time. The optimal reaction conditions of PCB removal from the soil were obtained experimentally when soil particle-size, electrical power, flow rate and reaction time were 5-10mm, 21w, 120mL. rain and 90rain, respectively. However, decreasing electrical power, flow rate and reaction time to 18 w, 60 mL. min- and 60 min respectively were also acceptable in view of the cost of remediation. This technique was characterized by the additional advantage of thorough oxidation of PCBs in the soil, with no formation of intermediate products after reaction. The technique therefore shows some promise for application in the remediation of soils contaminated with persistent organic pollutants in brown field sites in urban areas.     

Bioremediation of highly contaminated oilfield soil: Bioaugmentation for enhancing aromatic compounds removal

This study evaluated the effectiveness of different amendments--including a commercial NPK fertilizer, a humic substance （HS）, an organic industrial waste （NovoGro）, and a yeast-bacteria consortium--in the remediation of highly contaminated （up to 6% of total petroleum hydrocarbons） oilfield soils. The concentrations of hydrocarbon, soil toxicity, physicochemical properties of the soil, microbial population numbers, enzyme activities and microbial community structures were examined during the 90-d incubation. The results showed that the greatest degradation of total petroleum hydro- carbons （TPH） was observed with the biostimulation using mixture of NPK, HS and NovoGro, a treatment scheme that enhanced both dehydrogenase and lipase activities in soil. Introduction of exogenous hydrocarbon-degrading bacteria （in addition to biostimulation with NPK, HS and NovoGro） had negligible effect on the removal of TPH, which was likely due to the competition between exogenous and autochthonous microorganisms. None- theless, the addition of exogenous yeast-bacteria consor- tium significantly enhanced the removal of the aromatic fraction of the petroleum hydrocarbons, thus detoxifying the soil. The effect of bioaugmentation on the removal of more recalcitrant petroleum hydrocarbon fraction was likely due to the synergistic effect of bacteria and fungi.     

Characterizing the vegetation community in the provenance slope with high-frequency debris flow北大核心CSCD

In order to explore the characteristics and species diversity of the vegetation growing in the provenance slope with high-frequency debris flow, we selected the slopes on the north and south sides of the valley in the Jiangjiagou watershed as the research object. The structural characteristics and quantitative compositions of the communities of vegetation growing on different positions of the slopes were investigated. The species composition, important value, species diversity, and ground and underground biomass of the different communities on the slope were statistically analyzed, and the correlations of the ground and underground biomass with the diversity were determined. The results showed that: of the total 49 species found, the herbs were the dominant flora, of which 33 were found on the northern slope and 23 were found on the southern slope. There were significant differences in the species composition and composition of the important values along the different positions on the slope, being mainly affected by the pioneer herbaceous plants. We found that Heteropogon contortus, Eulaliopsis binata, Arthraxon hispidus, and Sesbania cannabina were highly adaptable to debris flow. These four species are common to the area and can be used as the main configuration species for future ecological restoration. There were differences in the community characteristics and species diversity at different positions on the slope. For the southern slope of the valley, the Shannon-Wiener diversity index was in the order: stable zone (2.311) > instable zone (2.161) > deposit zone (2.036), and in the order: deposit zone (2.626) > stable zone (1.338) > instable zone (1.057) for the northern slope. There were significant differences in the biomass, being in the order: stable zone > instable zone > deposit zone, with higher values in the northern slope than in the southern slope. Based on the aforementioned results, we suggest that the restoration of vegetation in the area of the provenance slope having high-frequency debris flow should focus on the prevention and protection of the instable zone of the slope by natural processes of recovery. The deposit zone needs rational remediation measures. We should introduce local shrub and arbor to increase the species composition and promote the development of plant communities with vertical structures. © 2018 Science Press. All rights reserved.