城市垃圾填埋场防渗浆材的实验研究

针对垃圾填埋场防渗的特殊要求,通过大量正交实验研究,研制了一种低渗透系数并对污染物有良好阻滞作用的浆材,即膨润土-水泥-粉煤灰(BCF)浆材,包括S型、N型和Z型3种类型。该浆材可泵期可调,结实率>99.6%,结石体28d渗透系数<0.65×10-7cm/s,N型的无侧限抗压强度<1.2MPa,弹性模量在200MPa左右。浆材结石体对COD、氨氮和磷的阻滞率均达到了82%以上,对酞酸酯和常见重金属离子的阻滞率均在99.6%以上。对浆材结石体的防渗性与对污染物阻滞性能的机理进行了研究,并提出渗滤沉积作用和吸附滞留作用阻滞机理。     

An emerging market for groundwater remediation in China: Policies,statistics, and future outlook

There is a rapidly emerging and potentially huge market for the remediation of contaminated groundwater in China. The Chinese government published a Water Action Plan in April 2015, a Soil Action Plan in May 2016, and a draft Soil Pollution Prevention and Control Law in June 2017. All of these new policies and regulations put pressures on local governments and contaminated site owners, obliging them to conduct site investigation and to cleanup contaminated groundwater. The Chinese population in northern regions heavily depend on groundwater, with nearly 70% of water supply coming from aquifer sources in the Beijing-Tianjin-Hebei region. However, poor groundwater quality due to natural geochemical background and anthropogeic pollution is a serious concern, with poor or very poor quality water observed in nearly 80% of groundwater monitoring wells in 17 northern provinces. Shallow groundwater in many areas has been contaminated by toxic pollutants such as heavy metals and chlorinated organic compounds. There is an urgent need to better understand the situation and to conduct groundwater remediation at contaminated sites. The Chinese government is investing heavily in the research and development for groundwater remediation, which is expected to greatly add to the quality and quantity of groundwater remediation projects in the near future.     

我国污染场地修复决策系统研究进展

自2016年《土壤污染防治行动计划》实施以来,随着污染土壤修复工作的推进,因场地污染类型、污染程度以及土地规划类型等因素的不同,如何筛选出科学、合理、高效、低耗的修复技术显得尤为重要。在此背景下场地修复决策系统应运而生,即通过输入修复过程所有要素并结合专家判断,修复决策系统运算得出最佳修复模式,为管理者提供决策依据。本文在分析国内外修复决策系统的发展现状、特点以及优势和劣势基础上,以焦化污染场地为例拟开发基于WebGIS的污染场地修复辅助决策系统,以找出适合我国污染场地修复决策的模式,为从事相关工作的研究者和决策者提供参考。     

污染场地卤代烃非生物自然衰减研究进展

传统的卤代烃自然衰减研究主要关注生物降解过程,然而近年有研究发现卤代烃可以被地层中的活性矿物还原降解.对天然活性矿物介导下卤代烃非生物自然衰减的研究进展总结显示,可以还原降解卤代烃的天然矿物主要包括铁硫矿物、铁氧矿物和含铁黏土矿物等,其中铁硫矿物在含水层中分布最为广泛.常见的反应机制包括还原消除、氢解、自由基加成、自由基偶联、脱卤化氢、水解,其中还原消除和氢解是其中最重要的两种反应机制,常见于卤代烷烃和卤代烯烃的非生物降解.卤代烃的非生物降解产物主要取决于还原降解途径和母体卤代烃.不同矿物对卤代烃的降解活性大致表现为马基诺矿?黄铁矿>黑云母>蛭石≈绿锈>磁铁矿≈蒙脱石.卤代烃的降解速率除受矿物种类影响外,还受到卤代烃种类、pH、硫化物浓度、共存金属离子、天然有机物、矿物形态等因素的影响.现有的研究已经确证活性矿物的还原降解是卤代烃自然衰减的重要机制,但该领域中仍然有一些重要知识点有待进一步研究.关于活性铁矿物Fe（Ⅱ）类型和反应能力之间的关系、还原卤代烃过程中Fe（Ⅱ）的结构变化以及结构态Fe（Ⅱ）向卤代烃的电子转移方式等仍然不清楚,建议进行更深入的研究;现有研究大都基于实验室小试装置,实际场地的研究不多,建议今后进一步探究实验室发现的规律是否符合场地中的实际情况;地下水位波动导致活性矿物间歇性暴露在溶解氧中,可能产生羟自由基（·OH）实现并导致卤代烃的氧化降解,这方面的研究目前尚存在不足,建议给予更多关注.      

模糊多属性决策在垃圾卫生填埋场选址中的应用

根据垃圾卫生填埋场选址的影响因素及其权重具有模糊性的特点,提出采用模糊多属性决策方法来解决垃圾卫生填埋场选址的问题。本文在分析垃圾卫生填埋场选址的主要影响因素的基础上,阐述了采用模糊多属性决策进行填埋场场址优选的思路、原理和方法,并通过具体算例证明了该法应用于填埋场选址的可行性与合理性。     

Efficiency and regulation of recruitment during colony emigration by the ant Temnothorax curvispinosus

Recruitment helps insect societies by bringing individuals to places where work needs to be done, but it also imposes energetic and opportunity costs. The net effect depends both on recruitment efficiency and on the ease with which insects can find work sites on their own. This study examined both of these factors for colony emigration by the ant Temnothorax curvispinosus. Emigrations were organized by a corps of active ants who transported the rest of the colony. These active ants either found new sites independently or followed tandem runs led by successful scouts. Although most tandem runs broke apart before reaching their target, even lost followers found the new site faster than did unguided searchers. When the new site was near the old nest, tandem runs were rare and summoned only a small proportion of the transporter corps. When the new site was instead distant and inconspicuous, tandem runs were common and brought roughly one third of the transporters. This pattern likely results from the quorum rule used by individual scouts to decide when to switch from tandem runs to transports. By monitoring how many nestmates have already found the nest, the ants ensure that the costs of recruitment are born only when necessary.     

某油泥堆放场地中多环芳烃的污染及其垂向分布特征

通过采集某油田油泥堆放场地及其周边24个表层土壤样品和2个剖面土壤样品,采用超声波萃取-气相色谱/氢火焰离子化检测分析方法,对美国环境保护局(USEPA)优控的16种多环芳烃(PAHs)进行定量分析.结果表明:该研究区域的PAHs污染已较为严重,污染场地内16种PAHs的检出率为100%,w(PAHs)平均值为7 770.7 ng/g;周边土壤的16种多环芳烃的检出率为58.3%～100%,二苯并［a,h］蒽及茚并［1,2,3-cd］芘的检出率相对较低,w(PAHs)平均值为2 038.8 ng/g.研究区域内主要污染物为萘、苊、二氢苊、芴、菲、蒽、荧蒽、、芘、苯并［a］蒽和苯并［a］芘.从母体PAHs与污染物来源的关系和单组分比值可以看出,污染场地内及周边土壤的污染源是石油源和燃烧源的混合源.w(PAHs)在土壤剖面中的峰值出现在40～60及20～40 cm处,不同组分的PAHs在土壤剖面中的迁移能力表现为2～3环PAHs＞4环PAHs＞5～6环PAHs.      

垃圾填埋场空气真菌群落结构和时空分布特征

为了解垃圾填埋场空气真菌的群落结构和浓度、粒径的时空分布,在北京市某垃圾卫生填埋场填埋区、渗滤液处理区、生活区分别选定监测点,利用安德森六级微生物采样器,对填埋场空气真菌进行了系统的定点取样和分析.结果表明,除无孢菌外,共出现了15属空气真菌.优势菌属依次为枝孢属(Cladosporium)、曲霉属(Aspergillus)、青霉属(Penicillium)、无孢菌群(Non-sporing).填埋区和渗滤液处理区空气真菌浓度约为1 750 CFU.m-3,明显高于生活区(p0.05).2006年4月~2007年1月空气真菌浓度变化曲线呈双峰型,2个高峰分别出现在5月和9~10月,浓度可达5 000 CFU.m-3以上.填埋区4~7月空气真菌09:00~11:00的浓度低于15:00~16:00,在8月~次年1月趋势相反.空气真菌粒子在Ⅲ~Ⅴ级约占总数的75%.填埋区和渗滤液处理区的空气真菌中值直径均为2.9μm,生活区为2.8μm,3个功能区空气真菌的中值直径没有差异(p0.05).     

加强矿山现场检查 规避矿山评价风险

针对矿山安全评价过程中现场检查的相关内容,分析了矿山现场检查的目的和意义,进一步明确了矿山现场检查的重点及要求,并探讨了矿山现场检查中应注意的问题以及规避安全评价风险的措施及建议。     

某垃圾卫生填埋场渗滤液处理工程实例及技术探讨

针对城市生活垃圾填埋场渗滤液的特点,提出了UASB＋MBR的处理工艺,结果表明,经该处理工艺,垃圾填埋场渗滤液中的NH3-N,CODCr,BOD5等指标均能达到GB16889—1997《生活垃圾填埋污染控制标准》中生活垃圾渗滤液排放限值的二级标准。