Migration of Heavy Metals from Polluted Soil to Plants and Lichens under Conditions of Field Experiment on the Kola Peninsula

Russian Journal of Ecology - We have carried out a field experiment to study the migration of Ni, Cu, and Co from the organic horizon of Al–Fe-humus podzols polluted with heavy metals (HMs)...     

炭化紫茎泽兰吸附生活污水中的有机物

紫茎泽兰目前已被列入我国首批外来入侵物种,排在第一位。为达到有效防控紫茎泽兰扩散的目的,对紫茎泽兰进行资源化利用是相对较佳的途径。通过对紫茎泽兰炭化处理后用于处理生活污水中的有机物,实现以害制废。采用等温吸附实验研究了炭化紫茎泽兰用作吸附剂吸附生活污水中有机物的吸附特性,并讨论了炭化紫茎泽兰吸附生活污水中COD的初始浓度、吸附时间、吸附温度、吸附剂投加量等影响因素。结果表明,当炭化紫茎泽兰的投加量为0.05 g,吸附接触时间为2 h,吸附温度为20℃,180 r/min,生活污水中进水COD浓度大于1 000 mg/L时,去除率可达62.9%。采用Langmuir、Freundlich吸附等温式对吸附平衡数据进行了拟合,结果表明吸附等温线符合Freundlich模型。     

皂化改性橘子皮生物吸附剂对重金属离子的吸附

以生物废料橘子皮(OP)为原料,经乙醇、氢氧化钠处理,得到改性橘子皮生物吸附剂SOP,将其用于对重金属离子Cu2+、Pb2+、Cd2+、Zn2+和Ni2+的吸附。研究了溶液pH、吸附时间和重金属离子初始浓度对SOP吸附性能的影响。结果表明,重金属离子在生物吸附剂上的吸附速率快,符合准二级动力学方程。SOP对重金属离子的吸附等温线符合Lang-muir模型,根据Langmuir模型计算SOP对Cu2+、Pb2+、Cd2+、Zn2+和Ni2+的饱和吸附量分别为56.82、152.4、66.27、33.90和23.02 mg/g,均高于改性前。常见阳离子的存在对重金属离子吸附的影响较小,改性后的橘子皮生物吸附剂可以再生重复使用4次以上,是性能良好的重金属离子吸附剂。     

Effects of sludge characteristics on electrical resistance and energy consumption during electro-dewatering process

The increase of electrical resistance (ER) and energy consumption (EC) during the later stage of dewatering is a major problem hindering the development of electro-dewatering (EDW) technology. As the variations of sludge characteristics are significant during the EDW process, the relationships between sludge characteristics and ER and EC during EDW remain unclear. In this study, the effects of moisture content (MC), thickness, pH, conductivity, zeta potential, temperature, and gas volume on the ER and EC during the EDW process were statistically investigated using correlation and multiple linear regression analyses. Herein, the results showed that the ER of the sludge near the anode was primarily affected by pH, whereas the sludge near the cathode was primarily affected by the MC and conductivity. Further, sludge temperature and conductivity were the most reliable indicators to predict the EC near the anode and cathode, respectively. The results of this study provide theoretical guidance useful for solving the increase of ER and EC during the later stage of the EDW process.     

Ecotoxicity assessment of heavy metals and crude oil based on biological characteristics of chernozem

Soil pollution with Cr, Cu, Ni, and Pb oxides or crude oil has an adverse effect on biological properties of ordinary chernozem. The degrees of their deterioration in laboratory and field experiments do not differ statistically, indicating that the results of laboratory modeling may be correctly extrapolated to the field scale. Pollution of ordinary chernozem with oil affects biological properties of both topsoil and subsoil horizons, while Pb is harmful only for the upper soil horizon. Concentrations in excess of 25 mg/kg for Pb and 0.25% for oil in ordinary chernozem are not ecologically safe (not allowable).     

多级微氧生物流化床预处理高浓度丙烯酸废水

采用多级微氧生物流化床反应器预处理高浓度丙烯酸废水,考察了进水负荷的影响,并对丙烯酸的降解产物进行了分析.结果表明,反应器在水力停留时间为12 h,水温25℃,进水丙烯酸为3 000～9 000 mg.L-1,丙烯酸容积负荷为6.0～18.0kg.(m3.d)-1的条件下,对丙烯酸去除率在95%以上,COD去除率为15%～30%,出水中丙烯酸浓度<150 mg.L-1.丙烯酸降解的主要中间产物为乙酸和丙酸,平均每1.00 mol的丙烯酸可转化成0.22 mol乙酸和0.36 mol丙酸.多级微氧生物流化床可实现丙烯酸废水的高负荷预处理.     

Effects of heavy metal pollution on the ecological and biological characteristics of common chernozem

A detailed comprehensive study on the effects of heavy metals on the biological activity and other characteristics of common chernozem of the southern European facies was performed. This involved the analysis of various microbiological and biochemical indices characterizing soil biological activity, their dynamics, a set of several metals and their different chemical forms, and a wide range of metal concentrations in the soil. New important aspects of the effects of heavy metals on biological processes in the soil were revealed. An integral method was proposed for assessing changes in the total biological activity of the soil on the basis of informative indices used in the monitoring, diagnosis, and indication of soils polluted with heavy metals. Geographic trends in changes of soil resistance to heavy metal pollution were analyzed within the common chernozem subtype and by comparing chernozem with other soils.     

高层建筑利用竖井排烟的全尺寸实验研究

通过开展全尺寸实验,对不同竖井高度、火源功率下,室内、补风口、竖井的温度变化,以及补风口、竖井内速度变化进行分析研究。结果表明:竖井内温升随距离竖井底部距离增加呈指数规律衰减,竖井内排烟速度随距离竖井底部距离增加逐渐减小。火源功率一定时,竖井高度增加,烟囱效应增强,控烟效果变好,当竖井高度由2.8 m增加至5.6 m时烟囱效应增加最显著;火源功率增大,烟囱效应也增强,但室内热压力的增大不利于补风口控烟,需适当提高排烟竖井高度或减小补风口面积。