Brominated flame retardants and heavy metals in automobile shredder residue (ASR) and their behavior in the melting process

The End-of-life Vehicles Recycling Act went into effect on January 1, 2005, in Japan and requires the proper treatment of airbags, chlorofluorocarbons (CFCs), and automobile shredder residue (ASR). The need for optimal treatment and recycling of ASR, in particular, has been increasing year after year because ASR is regarded as being difficult to treat. Dioxin-related compounds, brominated flame retardants (BFRs), heavy metals, chlorine and organotin compounds are all present in high concentrations in ASR. The authors conducted ASR melting treatment tests using a 10-tons/day-scale direct melting system (DMS), which employs shaft-type gasification and melting technology. The results obtained showed that dioxin-related compounds and BFRs were decomposed by this melting treatment. The high-temperature reducing atmosphere in the melting furnace moved volatile heavy metals such as lead and zinc into the fly ash where they were distributed at a rate of more than 90% of the input amount. This treatment was also found to be effective in the decomposition of organotin, with a rate of decomposition higher than 99.996% of the input amount. Via the recovery of heavy metals concentrated in the fly ash, all the products discharged from this treatment system were utilized effectively for the complete realization of an ASR recycling system that requires no final disposal sites.     

枯水季和丰水季长江口海域生源硫的浓度变化特征及影响因素

为深入研究河口近岸海域DMS（二甲基硫）的生物地球化学过程,于2014年2月（枯水季）和7月（丰水季）对长江口及附近海域表层海水中DMS及其前体物质DMSP（二甲巯基丙酸内盐）的浓度分布及影响因素进行了研究,测定了DMSPd（溶解态DMSP）的降解速率和DMS的生物生产与微生物消费速率,并估算了DMS的海-气通量.结果表明:①枯水季和丰水季c（DMS）、c（DMSPd）、c（DMSPp）（DMSPp为颗粒态DMSP）的平均值±标准偏差分别为（0.54±0.28）（2.04±1.32）（6.65±5.07）和（3.99±3.70）（5.57±4.72）（14.26±9.17）nmol/L,长江口海域丰水季生源硫化物的浓度明显高于枯水季.②枯水季和丰水季c（DMSPd）与ρ（Chla）均呈弱相关,说明浮游植物在控制长江口海域DMSP的生产分布中发挥重要作用.③枯水季和丰水季c（DMS）/ρ（Chla）的平均值±标准偏差分别为（2.62±3.28）和（4.60±7.49）mmol/g,表明丰水季DMS的高产藻种（甲藻）在浮游植物生物量中所占比例高于枯水季.④枯水季表层海水中DMSPd的降解速率和DMS的生物生产速率分别介于（2.84~30.53）和（0.52~2.19）nmol/（L·d）之间,平均值分别为14.55和1.30 nmol/（L·d）,表明DMS并不是DMSPd的主要降解产物.⑤枯水季和丰水季DMS的海-气通量平均值±标准偏差分别为（0.36±0.32）和（2.17±2.98）μmol/（m2·d）,而且丰水季的硫排放量明显高于枯水季,这主要与夏季较高的c（DMS）有关.研究显示,长江口海域生源硫化物的浓度变化及分布特征呈明显的季节性差异,河口近岸海域是海洋有机硫排放的重要区域.      

2017年9月东海海水和大气中挥发性有机硫化物的浓度分布及其来源

挥发性有机硫化物（volatile organic sulfur compounds，简称VSCs）是硫循环的主要参与者，在全球气候变化和大气化学中发挥重要作用.于2017年9月运用冷阱捕集气相色谱和气-质联用法对东海海水与大气中3种重要的VSCs即羰基硫（COS）、二甲基硫（DMS）、二硫化碳（CS₂）的浓度进行了测定，并计算了它们的海-气通量.研究结果表明，秋季东海表层海水中COS、DMS和CS₂的浓度平均值分别为（0.14±0.08）、（3.58±2.81）和（0.06±0.06）nmol·L^-1.大气中COS、DMS和CS₂的平均浓度分别为（414.9±107.4）×10^-12、（39.7±29.9）×10^-12和（92.9±55.6）×10^-12，COS是大气中含量最丰富的VSCs.相关性分析表明，海水中DMS与CS₂存在相关性，推测两者具有相似的来源途径.大气中COS和CS₂的浓度相关性较为显著，显示大气中CS₂是COS的主要源.此外，海水中COS、DMS和CS₂都呈过饱和状态，海-气通量平均值分别为（0.45±0.58）、（13.15±12.66）和（0.20±0.22）μmol·m^-2·d^-1，表明秋季东海是大气中3种VSCs的源.     

Temporary disaster debris management site identification using binomial cluster analysis and GIS

An essential component of disaster planning and preparation is the identification and selection of temporary disaster debris management sites (DMS). However, since DMS identification is a complex process involving numerous variable constraints, many regional, county and municipal jurisdictions initiate this process during the post‐disaster response and recovery phases, typically a period of severely stressed resources. Hence, a pre‐disaster approach in identifying the most likely sites based on the number of locational constraints would significantly contribute to disaster debris management planning. As disasters vary in their nature, location and extent, an effective approach must facilitate scalability, flexibility and adaptability to variable local requirements, while also being generalisable to other regions and geographical extents. This study demonstrates the use of binomial cluster analysis in potential DMS identification in a case study conducted in Hamilton County, Indiana.     

Dimethylsulphide and ocean–atmosphere interactions

Dimethylsulphide (DMS) is a trace sulphur gas found in most atmospheric and surface water samples, which is derived from dimethylsulphonioproprionate (DMSP). Although it has been extensively studied over the last 50 years, its natural production, consumption and cycling are still not completely understood. Until recently, DMS was believed to originate mainly from marine waters, but later studies have shown that estuaries and lakes are also an important source of DMS. DMS also originates from terrestrial plants such as maize, wheat and lichen, but it is not fully understood why. DMS is believed to have an important impact on the global environment by influencing factors such as the acidity of the atmosphere, cloud condensation nuclei (CNN) and solar insolation. The impact that humans have on the cycling of DMS and on its environmental impact is not well understood either. DMS is affected by temporal and geographical factors, as well as physical factors such as salinity and wind speed, yet when studied under El Niño conditions which modify these physical factors in vivo, there was found to be no fluctuation in the concentration of DMS in the water column. This review outlines our current state of knowledge on DMS.     

颗石藻藻源性二甲基硫丙酸（DMSP）在致死卤虫时的作用检测(The Detection of Lethal Effects of Algal Derived DMSP of Pleurochrysis carterea on Artemia salina)

颗石藻Pleurochrysis carterea具有显著致死卤虫的作用,但机理尚需进一步解明.为了分析颗石藻藻源性的二甲基硫丙酸(DMSP)及其分解产物二甲基硫(DMS)和丙烯酸是否是致死卤虫的原因所在,检测了P.carterae在受卤虫捕食压力情况下细胞DMSP及其裂解产物DMS的定量变化,以及外源DMSP、DMS和丙烯酸对卤虫的直接作用.结果显示,外源添加的高挥发性DMS对卤虫无节幼虫没有急性致死效应.外源重复添加浓度为0.08至1.0mM的DMSP和丙烯酸对卤虫的致死存在浓度和时间相关的效应,浓度越高发生卤虫大量死亡的时间越早.检测外源重复添加DMSP和丙烯酸时的pH变化发现,试剂重复添加会造成pH显著下降,这可能是致死卤虫真实的直接原因.捕食者与被捕食者系统中,检测颗石藻液中藻源性DMSP及裂解产物的定量水平并未达到显著致死卤虫的作用.但是,考虑颗石藻被卤虫重复捕食入体内的累积变化时,从理论值分析来看,颗石藻在卤虫体内的裂解可能对体内产生脉冲式的累积过低酸刺激,或许是造成卤虫的死亡原因.     

生物滴滤塔净化含硫混合废气

利用甲硫醚(DMS)降解菌Alcaligenes sp.SY1和丙硫醇(PT)降解菌Pseudomonas putida.S-1强化生物滴滤塔(BTF)处理DMS和PT的混合废气,研究了其挂膜启动及稳定运行阶段的降解性能,并考察了该系统同时去除H2S的能力.结果表明,BTF在DMS和PT进口浓度均为50 mg·m-3,EBRT为30 s的条件下,运行11 d即可完成挂膜启动,填料上的生物量明显增加,DMS、PT的去除率分别可达到90%和100%.系统稳定运行时,DMS和PT的最大去除负荷分别为8.7 g·(m~3·h)~(-1)和12.4 g·(m~3·h)~(-1),PT的去除效果更佳.DMS和PT混合废气在降解过程中,PT对DMS的降解有较明显的抑制作用,当PT进气浓度大于51 mg·m-3时,DMS的去除效率下降.BTF还能同时有效去除H2S,当混合废气中H2S浓度达到230 mg·m-3时,H2S去除率仍能高达98%,但是115 mg·m-3以上的H2S会对DMS的降解产生不利影响.     

春季厦门海域表层海水中二甲基硫的含量分布

采用固相微萃取(SPME) 气相色谱法(GC)测定了厦门海域20个站位表层海水中DMS二甲基硫的含量,并对其分布进行分析。结果表明,厦门海域DMS含量在0 65～40 69nmol·L-1,平均浓度为12 83nmol·L-1。其中,西海域的含量最高,东海域次之,同安湾最低。与其它海域海水中DMS浓度比较,厦门海域DMS含量较高,浓度变化范围大,与叶绿素a浓度及表层水温、盐度之间无明显的相关关系。