Leaching behavior of heavy metals and PAHs from MSWI bottom ash in a long-term static immersing experiment

Bottom ash is the main solid residue (in weight) which is produced by municipal solid waste incineration (MSWI) facilities. This material is composed of a mineral matrix and may be used as secondary raw material for construction purpose. However, for this specific application the leaching behavior of the environmentally relevant elements under field conditions is different from the predicted behavior based on results obtained from the standardized leaching test. Therefore, a 70-day simulative experiment has been carried out in this study to investigate the release of major heavy metals (Cu and Pb) and polycyclic aromatic hydrocarbons (PAHs) from several particle fractions of bottom ash under a static leaching condition, where bottom ash was immersed in water at different initial pH values. Results showed that: (1) the leaching behavior of Cu and Pb was much similar with that depicted by the standardized leaching tests, and fit well with the solubility-controlling mechanism; (2) the sorption mechanism on the neoformed phases may control the solubility of Pb, whereas the dissolved organic carbon (DOC) may play an important role in the solubility of Cu; and (3) the leached PAHs were degraded during the later period of leaching process.     

Investigation of the accumulation of ash,heavy metals,and polycyclic aromatic hydrocarbons to assess the stability of lysis–cryptic growth sludge reduction in sequencing batch reactor

The accumulation of ash, heavy metals, and polycyclic aromatic hydrocarbons (collectively called potential accumulating substances, PAS) was evaluated to ascertain the stability of lysis–cryptic growth sludge reduction process (LSRP) for municipal sludge treatment. One sequencing batch reactor (SBR) incorporated with homogenization was run to test the LSRP and another SBR as a control. The continuous monitoring results for 2 months showed that the ash and heavy metals slightly increased, and the polycyclic aromatic hydrocarbons decreased by 18.0%, indicating that there may be negligible accumulations during the LSRP. Their accumulations met pattern I, as demonstrated by statistical analysis, proving no PAS accumulation for LSRP. This was further confirmed by sludge activity and system performance. Moreover, the mechanism for no PAS accumulation was discussed. It was concluded that the LSRP was stable with no worries about PAS accumulation under the operational conditions.     

贵州珍稀濒危药用植物与可持续开发利用

通过调查贵州珍稀濒危药用植物的种类、分布、现状及用途，为该省珍稀濒危药用植物的合理开发利用提供依据。采用实地调查、资料查阅、市场调研，然后作出评估与评价。结果表明，贵州珍稀濒危药用植物种类较多，具有良好的开发应用前景。贵州珍稀濒危药用植物的开发利用应走深度开发、可持续利用模式。     

Knowledge map and global trends in extreme weather research from 1980 to 2019: a bibliometric analysis

Environmental Science and Pollution Research - There is an increasing number of studies focusing on extreme weather all over the world, but global trends and research topics related to extreme...     

废铁屑-改性粉煤灰联用处理铬渣渗滤液

针对铬渣严重污染环境问题,以"以废治废"为研究目标,采用室内静态实验方法,进行废铁屑-改性粉煤灰联用处理铬渣渗滤液中Cr(Ⅵ)和总铬实验研究。实验结果表明,废铁屑与聚合氯化铝改性粉煤灰联用处理Cr(Ⅵ)和总铬效果优于单独采用其中一种物质;处理Cr(Ⅵ)浓度208 mg/L、总铬浓度260 mg/L的200 mL高浓度含铬废水最佳反应条件为:反应时间30 min,总投加量40 g,配比为1:1, pH值4.1,对应Cr(Ⅵ)去除率99.93%,总铬去除率99.72%。处理后水质满足《污水综合排放标准》(GB 8978-1996)要求。     

添加剂升温烧蚀法在制备新型介孔水环境净化材料中的应用

首次探索了一种破坏式造孔与有机复合相结合的新方法以制备介孔复合水环境净化材料,使最终产品成为一种具有广谱孔结构分布的复合环境材料。详细介绍了该方法的第二步工艺即添加剂升温烧蚀法,在优化后的最佳条件下,产品的孔径得到了进一步扩大,其中部分孔道直径可达至介孔级,同时材料的表面得到了进一步活化。经此步工艺后,所制备的中间产品染料吸附量是原材料的194倍,是酸洗刻蚀后产品的122倍;24h吸湿率是原材料的38倍,是酸洗刻蚀后产品的19倍。     

进出料频率对牛粪两相厌氧发酵特性的影响

以牛粪为发酵原料,在中温(35±2)℃的条件下,采用自行设计的两相厌氧发酵中试装置,在水力停留时间确定的前提下,酸化原料分别以每天、间隔1 d和间隔2 d 3种不同进出料频率加入产甲烷罐,观察挥发性固体(VS)产气率和甲烷含量的变化情况。实验结果表明:保持产酸相与产甲烷相水力停留时间(HRT)分别为3 d和17 d,每天进出料产气效果最佳,原料VS产气率和甲烷含量最大值分别为0.29 m3/(kg·VS)和58.36%。     

How can green building development promote carbon emission reduction efficiency of the construction industry?——Based on the dual perspective of industry and space

Environmental Science and Pollution Research - Green building development(GBD) plays an important role in improving carbon emission reduction efficiency of the construction industry(CEEOCI), and...     

天津市医疗废物处置规划及策略研究

以天津市医疗废物管理现状为研究对象，对处置方式进行深入探讨，分析目前分散处置和集中处置存在的缺陷，提出“区域集中处置”设想；并运用模糊决策模型理论，建立较完善的处置方式评价指标体系，应用模糊综合评价模型得出“区域集中处置”是最佳的医疗废物处置方式，同时提出了相应的区域集中处置策略。     

Influence of Al-oxide on pesticide sorption to woody biochars with different surface areas

Biochars’ properties will change after application in soil due to the interactions with soil constituents, which would then impact the performance of biochars as soil amendment. For a better understanding on these interactions, two woody biochars of different surface areas (SA) were physically treated with aluminum oxide (Al-oxide) to investigate its potential influence on biochars’ sorption property. Both the micropore area and mesopore (17～500 Å in diameter) area of the low-SA biochar were enhanced by at least 1.5 times after treatment with Al-oxide, whereas the same treatment did not change the surface characteristics of the high-SA biochar due partly to its well-developed porosity. The enhanced sorption of the pesticide isoproturon to the Al-oxide-treated low-SA biochar was observed and is positively related to the increased mesopore area. The desorption hysteresis of pesticide from the low-SA biochar was strengthened because of more pesticide molecules entrapped in the expanded pores by Al-oxide. However, no obvious change of pesticide sorption to the high-SA biochar after Al-oxide treatment was observed, corresponding to its unchanged porosity. The results suggest that the influence of Al-oxide on the biochars’ sorption property is dependent on their porosity. This study will provide valuable information on the use of biochars for reducing the bioavailability of pesticides.