微砂+磁沉降快速除污工艺试验研究

为了探讨微砂在磁沉降快速除污工艺中的应用,设计了微砂和聚合氯化铝(PAC)的最佳组合试验,分析影响微砂在磁絮凝中絮凝效果的因素。结果表明:当微砂投加量为300 mg/L,PAC投加量为80 mg/L,磁场强度为300 mT,pH为6时,微砂在磁絮凝中具有最佳处理效果,对TSS、COD和TP去除率分别达到最大值93.66%、74.29%和89.10%。同时在投加微砂和磁沉降的共同作用下,水力停留时间仅为8 min。     

松花江哨口至松花江村段浮游植物光合作用产氧模型研究

为研究松花江哨口至松花江村江段的水环境容量,本文从浮游植物光合作用机理出发,利用连续３年多项指标实测资料,采用外包线法,初步确定一种浮游植物光合作用产氧率计算关系式。将这种方法应用于研究江段效果较好,经相关性检验,r＝0.90,r＞r_0.01,相关性极显著。该计算式能否用于哨口至松花江村以外的江段,尚需进一步验证。     

化学沉淀与高级氧化法处理乙烯裂解废碱液的研究

采用化学沉淀与高级氧化(UV／H2O2)法去除乙烯裂解废碱液中的硫化物及有机物。考察了影响效果的各种因素。试验结果表明：化学沉淀在反应温度为20℃、反应时间为30min、CuO与Na2S的摩尔比为1．45：1;高级氧化反应温度为40℃、反应时间为120min、H2O2的加入量(H202／COD质量比)为0．8的条件下,废碱液中S^2-的去除率可达98％以上,COD总去除率可达87％,BOD5／COD由处理前的0．21提高至0．54。     

New models for calculating the electrical resistivity of loess affected by moisture content and NaCl concentration

Environmental Science and Pollution Research - Saline loess is an important cause of environmental geo-issues in northwest China. In this research, electrical resistivity of loess with different...     

Improving immobilization efficiency and mechanism analysis of sodium hexametaphosphate on MgO-based cementitious material solidified MSWI FA

Journal of Material Cycles and Waste Management - MgO-based cementitious material (MCM) is a potential green substitute for solidifying municipal solid waste incineration fly ash (MSWI FA). Sodium...     

Investigation of microplastic pollution on paddy fields in Xiangtan City,Southern China

Microplastics (MPs) have become a hot issue of environmental pollution. However, insufficient evidence exists regarding the distributions and fates of MPs in terrestrial environment, especially in farmlands. The distributions of MPs in paddy fields were investigated in Xiangtan City, a typical rice production area in China. The abundance of MPs in paddy seedling raising fields was 3805?±?511 n·kg^?1, which increased by approximately 9 times than that in common paddy fields. Transparent films became the dominant forms due to the huge usage of mulching films, corresponding to that the proportion of polyvinyl chloride (PVC) increased to 17% there. Moreover, an industrial plant nearby also contributed considerably to the MP pollution; the proportion of PVC (33%) in the paddy fields nearby increased to approximately 4 times of common paddy fields, while polyvinyl alcohol (PVA; 13%) used as an important chemical raw material to synthesis in various applications was uniquely detected there. These results highlight the input of MPs from agricultural and industrial activities in farmlands. Their contributions to the MP pollution in farmlands should be continuously investigated.

     

From waste tire to high value-added chemicals: an analytical Py-GC/TOF–MS study

Environmental Science and Pollution Research - A Pyroprobe 5000 pyrolyzer connected to a gas chromatography-time-of-flight mass spectrometry (Py-GC-TOF–MS) was used to analyze the...     

Physicochemical and nutritional features of Gleditsia japonica shell biochar under different pyrolysis conditions

Journal of Material Cycles and Waste Management - This study aimed to investigate the effects of pyrolysis temperature (200–700 °C) and duration (2 h, 4 h) on...     

建筑垃圾资源化利用项目中特许经营模式的适用和争议——基于江苏省的实践启示

特许经营模式能够较好地发挥市场化、效率化、竞争化导向作用,充分发挥市场机制在资源配置中的决定性作用,在建筑垃圾资源化利用项目中得到了一定的应用。本文在分析江苏省建筑垃圾资源化利用项目中特许经营模式的实践经验和面临问题的基础上,总结了特许经营模式典型的交易结构,从物品属性、市场逻辑、风险分担和垄断之争四个方面对存在的争议问题和观点进行辨析,提出了国家层面制定规则、科学选择运作方式、确保采购充分竞争、合理确定项目补贴、加强政府规制作用和持续优化营商环境等政策建议,以期为未来建筑垃圾资源利用推广采用特许经营模式提供参考和启示。