美国大气挥发性有机物控制历程及对中国的启示

鉴于大气挥发性有机物(VOCs)对中国区域大气复合污染的重要影响,基于大量文献调研,从政策、法律法规、标准和管理手段等方面系统梳理了美国VOCs的控制历程,并从VOCs总量削减和O3浓度变化等角度评估了控制效果.研究表明:美国的VOCs控制体系是卓有成效的,1970年-2010年间共削减VOCs 1 551.4万吨,降幅为50.6％;而且,通过控制VOCs的排放实现了对臭氧(O3)污染协同控制的初衰.该研究结果对中国VOCs控制具有重要借鉴意义.     

活性污泥吸附废水中的铍

探讨了活性污泥吸附处理含铍废水的吸附动力学特性及吸附模型,研究了吸附后铍在活性污泥上的存在形态。实验结果表明,铍离子在活性污泥上的吸附行为遵循二级动力学规律,活性污泥在溶液中的分散性非常好,污泥微孔内扩散效应不是吸附过程的主要控制步骤,扩散速率主要由液相向固相的传质速率所控制,铍在污泥上的吸附主要为快速的表面吸附。铍在活性污泥上的吸附数据既可用Freundlich方程描述,也符合Langmuir吸附规律,Langmuir曲线的相关性还较Freundlich曲线高,吸附过程受温度影响不大,通过对处理后污泥的连续提取实验研究可知,处理后的活性污泥中铍的主要存在形态为有机结合态、残渣态和交换态。     

《国家危险废物名录》在危险废物管理中的存在的问题

本文介绍了我国危险废物名录目前的现状,分析了危险废物名录在危险废物监管中存在的问题,对危险废物的监管提出了建设鉴定机构、严格鉴定程序、豁免制度等建议。     

Chemical composition and source apportionment of PM10 and PM2.5 in different functional areas of Lanzhou, China

To elucidate the air pollution characteristics of northern China, airborne PM_10(atmospheric dynamic equivalent diameter ≤ 10 μm) and PM_(2.5)(atmospheric dynamic equivalent diameter ≤ 2.5 μm) were sampled in three different functional areas(Yuzhong County,Xigu District and Chengguan District) of Lanzhou, and their chemical composition(elements, ions, carbonaceous species) was analyzed. The results demonstrated that the highest seasonal mean concentrations of PM_10(369.48 μg/m~3) and PM_(2.5)(295.42 μg/m~3) were detected in Xigu District in the winter, the lowest concentration of PM_(2.5)(53.15 μg/m~3) was observed in Yuzhong District in the fall and PM_10(89.60 μg/m~3) in Xigu District in the fall.The overall average OC/EC(organic carbon/elemental carbon) value was close to the representative OC/EC ratio for coal consumption, implying that the pollution of Lanzhou could be attributed to the burning of coal. The content of SNA(the sum of sulfate, nitrate,ammonium, SNA) in PM_(2.5)in Yuzhong County was generally lower than that at other sites in all seasons. The content of SNA in PM_(2.5)and PM_10 in Yuzhong County was generally lower than that at other sites in all seasons(0.24–0.38), indicating that the conversion ratios from precursors to secondary aerosols in the low concentration area was slower than in the area with high and intense pollutants. Six primary particulate matter sources were chosen based on positive matrix factorization(PMF) analysis, and emissions from dust, secondary aerosols, and coal burning were identified to be the primary sources responsible for the particle pollution in Lanzhou.     

绿色建筑小区雨水资源化综合利用技术

运用生态学原理设计绿色建筑小区已逐渐成为潮流,节水与水资源利用的问题正日益受到关注.绿色建筑小区雨水资源化综合利用技术集成优化了小区雨水收集与分散处理系统、雨水集中收集与处理系统、雨水渗透系统等技术,具有投资省、处理效果好、管理方便等优点,适合为今后的绿色建筑小区雨水资源化综合利用建设参考.     

实际污水与模拟污水活性污泥系统的特性差异

实验中经常采用人工配置的模拟生活污水,为了研究其与实际生活污水活性污泥系统的特性差异,采用2个序批式间歇反应器(SBR)进行平行实验(厌氧、好氧方式运行),系统地考察了在进水主要组分和运行参数相同的情况下,不同原水对活性污泥系统脱氮、除磷、比好氧速率、污泥絮体形态和出水水质等方面的影响。结果表明,模拟污水系统的硝化活性强于实际污水系统,两者的平均硝化速率分别为7.43 mg NH4+-N/(L.h)和5.55 mg NH4+-N/(L.h)。在前置厌氧段,模拟污水系统的释磷量比实际污水系统高出36.45%。两者在后续好氧阶段都能够充分吸磷。模拟污水系统的平均比好氧速率(SOUR)高达64.54 mg O2/(g MLSS.h),而实际污水系统的则只有32.81 mg O2/(g MLSS.h)。模拟污水系统的污泥絮体疏松,粒径小,形状不规则,沉降性差,沉后出水平均悬浮物浓度(SS)为20 mg/L;而实际污水系统的污泥絮体则密实、粒径大,沉降性好,沉后水十分清澈,SS几乎检测不出。     

碳酸钙和粉煤灰对铅胁迫下小麦毒害的缓解效应

采用室内盆栽和网室盆栽的方法,研究了碳酸钙和粉煤灰对铅污染土壤的小麦幼苗生物效应、成熟期籽粒含铅量和蛋白质含量及生物产量的影响,探讨了碳酸钙和粉煤灰缓解铅毒害小麦的生理机制.结果表明,在轻度铅污染(铅为350 mg/kg)的小麦农田,1.0 g/kg碳酸钙或50 g/kg粉煤灰对小麦生长有明显的促进作用.能有效缓解铅对小麦的毒害;在重度铅污染(铅为600mg/kg)的小麦农田,1.0～2.0 g/kg碳酸钙或50～100 g/kg粉煤灰对小麦铅毒害缓解效果较好.     

Self-feedback LSTM regression model for real-time particle source apportionment

1. Download : Download high-res image (303KB)
2. Download : Download full-size image