废旧硬质聚氨酯泡沫塑料的木质素改性及再生

采用含有二乙二醇(DEG)和乙醇胺(ETA)的双组分解交联剂降解废旧硬质聚氨酯泡沫塑料(PU硬泡),并利用降解得到的低聚物多元醇与木质素复合制备出性能增强的再生PU硬泡。通过对制备的再生PU硬泡的红外光谱、密度、吸水率、抗压强度、热稳定性、导热系数、热重曲线等进行分析测试,考察m(DEG)∶m(ETA)对再生PU硬泡性能的影响。实验结果表明:m(DEG)∶m(ETA)=1∶3时废旧PU硬泡的降解效果最好;木质素加入量为2.0%(w)时再生PU硬泡的密度低、抗压强度高、保温性能良好,达到国家标准《建筑绝热用硬质聚氨酯泡沫塑料》(GB/T 21558—2008)的品质要求。     

吸附—电化学法组合工艺处理废乳化液

以季铵盐改性硅藻土为吸油剂,采用吸附—电化学组合工艺处理拉丝废乳化液,优化了工艺条件。实验结果表明,在乳化液pH为5.0、吸油剂加入量为20 g/L、反应温度为25 ℃的最优条件下吸附除油15 min,然后在清液pH为8.5、阳极电流密度为4 A/dm²的最优条件下电化学反应4 h后,废水无色无味,COD为43 mg/L,ρ（NH₃-N）=0,ρ（Cu）= 1.6 mg/L,ρ（Zn）= 3.7 mg/L,浊度为1.1 NTU,达到GB 8978—1996污水综合排放标准。     

生物滴滤塔处理模拟甲硫醚废气

在常温条件下,采用生物滴滤塔处理模拟甲硫醚废气,考察了气体空床停留时间(EBRT)、容积负荷、喷淋密度及营养液pH对生物滴滤塔性能的影响。实验结果表明:当EBRT为90 s、进气甲硫醚质量浓度为150 mg/m~3、喷淋密度为0.65 m~3/(m~2·h),营养液pH为6.8时,甲硫醚去除率为90%;容积负荷高于15 g/(m~3·h)时,对生物滴滤塔的性能产生抑制作用;EBRT为90 s及60 s时,最佳喷淋密度分别为0.56~0.65 m~3/(m~2·h)及0.65~0.75 m~3/(m~2·h);降解甲硫醚的微生物对pH的变化较敏感,最适营养液pH为6~7。     

Producing biodiesel from waste animal oil by modified ZnO

Biodiesel produced by transesterification of waste animal oil is a promising green fuel in the future. ZnO-Al₂O₃ and ZnO/Zn₂Al composition oxides were prepared by co-precipitation method and impregnation method, respectively. The above catalysts were characterized by X-ray diffraction (XRD), Brunauer--Emmett--Teller (BET) and CO₂ adsorption and temperature-programmed desorption (CO₂-TPD) and show that the high activity for the catalyst is attributed to its high alkalinity. The reaction parameters were optimized and the results show that the transesterification ratio of waste animal oil can reach 98.7% with 10% ZnO/Zn₂Al catalyst after 2 h. Moreover, 10%ZnO/Zn₂Al compound oxides can be active for the successive cycles. The glycerol as a predominant by-product after transesterification is of high purity with high use value.     

Some happy,others sad: exploring environmental justice in solid waste management in Kinshasa,The Democratic Republic of Congo

This paper explores the concept of environmental justice (EJ) in solid waste management (SWM) in Kinshasa, the Democratic Republic of Congo (DRC). It evaluates the extent to which EJ occurs in SWM and discusses the factors accounting for this state of affairs. The paper examines the relevant theoretical framework(s) and mechanisms that would facilitate the attainment of EJ in Kinshasa. It is argued that solid waste (SW) often ends up in the poorest and least powerful communities in the cities of the DRC. A qualitative research methodology, which includes exhaustive critical review of the literature, system analysis, reflections from best practices through case studies and discussion with stakeholders, was used for this study. Findings revealed that SWM in Kinshasa is a duty entrusted to publicly-funded municipal authorities. There are evidences of a clear divide between the rich and poor neighbourhoods in the manner SW is managed. This is an inequality that has only recently begun to be recognised as injustice practices in SWM. It is argued that a politico-cultural mechanism on remedying SWM inequities could enable changes that will address EJ in Kinshasa. Such a solution will go directly against the prevailing notion “some happy, others sad”.     

金属冶炼进口物料的固体废物鉴别方法

建立了金属冶炼进口物料的固体废物鉴别方法,并利用该方法对海关查扣的3种金属冶炼进口物料进行了固体废物鉴别。鉴别结果显示:物料1、2和3的自然属性分别为砷含量超标铜精矿、锰阳极泥、回转窑氧化锌,产生来源分别为有害物质超标的产品、污染控制设施产生的物质、有意识加工的目标产物;物料1和2属于我国禁止进口的固体废物,物料3不属于固体废物。本文建立的固体废物鉴别方法可行,可为金属冶炼进口物料的固体废物鉴别和监管提供参考。     

生物反应器填埋的沉降加速效应

通过实验室填埋柱模拟实验,研究了生物反应器填埋操作方式对填埋层沉降的影响。结果表明：与传统卫生填埋方式相比,回灌经厌氧生物处理后渗滤液的生物反应器填埋方式能够加速填埋层的沉降,140 d内沉降提高比例达10%以上。我国填埋垃圾高含水率、高易腐有机物含量的特性,使得其填埋层的次沉降系数高于文献值。填埋垃圾有机物降解量及其引起的垃圾水分排出量与填埋层沉降有显著相关性,表明有机物降解是引起填埋层沉降的重要因素,也是造成生物反应器填埋与传统卫生填埋方式初期沉降差异的主要原因。     

生活垃圾加载介质层填埋法对初期渗滤液污染抑制效果研究

以传统卫生填埋柱R2为对照,通过往生物反应器填埋柱R1内加载可渗透反应介质层1和2进行模拟试验,主要探讨了填埋柱R1垃圾渗滤液COD、总氮、氨氮及总磷的变化趋势,探索一种新型的加载介质层垃圾填埋处理方法。试验结果表明,填埋20周后, R1柱COD浓度基本维持在40 000～45 000 mg/L间,约为R2柱的20%～30%;第24周,R1柱总氮和氨氮分别为206.5 mg/L和167.3 mg/L,在16～24周内,R1总氮和氨氮分别约为R2的14.5%～17.5%和36.2%～43.6%;18周时,R1柱总磷达最大值1.704 mg/L,至第24周降为0.673 mg/L, 整个实验过程R1柱总磷约为R2的0.15%～0.56%。     

废弃印刷线路板碘化法浸金研究

针对碘化法从废弃印刷线路板中提取金的工艺设计,分别考察了碘的质量分数、n(I₂)/n(I^-)比值、固液比、双氧水的质量分数、pH值、浸出时间和浸出温度对金浸出率的影响。结合正交设计优化实验方法,提出了从废弃印刷线路板中碘化法浸取金的最佳工艺条件：碘的质量分数为1.1％,n(I₂)∶n(I^-)=1∶10,双氧水的质量分数为1.5％,浸出时间4 h,固液比为1∶10,浸出温度为常温（25℃）,溶液pH值为中性,此时金浸出率可达97.5％。     

砒霜生产化工厂危险废物处置工程设计

通过对砒霜生产化工厂原场址废渣及污染场地调查的基础上,进行了处置方案比选及技术经济比较,确定了就地安全填埋的处置方案。根据区域性危险废物集中安全填埋场的设计经验,本工程采用先进的HDPE双层防渗的安全填埋方式,并设置了雨水分流系统、渗滤液收集系统、封场处理和填埋气体导排系统,整个场区布置合理,对周围环境的影响小,投资少,取得了良好的社会效益和环境效益,并对危险废物处理处置工程设计中应注意的问题提出了建议。