ASsessment Of Alcohol Ethoxylate Surfactants And Fatty Alcohols Mixtures In River Sediments And Prospective Risk Assessment

A feasible and relatively readily available analytical method was adapted for the assessment of alcohol ethoxylates (AE) and fatty alcohols (FA) in sediments. This study illustrates the simultaneous measurement of 38 of 114 possible alcohol ethoxylate ethoxymers (AE) and fatty alcohols (FA) found in commercially important AE products. We predicted toxicity for all identified fractions, as well as the total mixture toxicity, relative to three exposure scenarios via sewage treatment plants (STP) for these widely used chemicals in consumer products and hence generate a preliminary environmental risk screening for AE and FA in sediments. The method is based on derivatization of solvent or solid-phase extracts with 2-fluoro-N-methylpyridinium p-toluenesulfonate (Pyr+). The derivatized extracts were analyzed with liquid chromatography/mass spectrometry (LC/MS) operating in the positive ion electrospray mode. The extraction efficiency of AE and FA in three different sediments of varying composition was evaluated with spike-recovery studies, ranging from 64% to 80%. The detection limits for individual ethoxymers typically ranged from 1 to 5ngg⁻¹on a dry weight basis. The mean limit of detection (LOD) was 6ngg⁻¹and the median LOD was 3ngg⁻¹. AE and FA in sediments were found to be stable for two weeks if preserved with 3% (v/v) formalin and stored at 4–6^∘C. Based on equilibrium partitioning, background concentrations of AE and FA were predicted to be below concentrations known to elicit chronically toxic effects. Total worst case mixture toxicities for all AE ethoxymers combined with FA were predicted to result in a risk quotient less than 0.6. Activated sludge treatment (STP) significantly reduced the release of total AE and FA by four-fold, suggesting that the total mixture risk quotient would be < 0.15 for sediment dependent organisms.     

有毒液体泄漏渗流污染后果分析

有毒液体泄漏后,沿地表扩散的同时亦会发生渗流现象.有毒液体渗流会直接或间接地对土壤和地下水及周边环境造成一定的污染,甚至会对人体造成很大危害,导致中毒等重大事故的发生.为分析泄漏后毒物的浓度在时间和空间上的变化规律,建立了二维渗流方程,开发了二维渗流事故后果分析软件.分析结果表明,在假设前提下,毒物泄漏后发生渗流时,毒物浓度沿二维渗流平面呈椭圆形向四周扩散,泄漏点的浓度随泄漏时间的推移而逐渐降低,此结论对于有毒液体泄漏的预防与控制具有重要的意义.     

Evaluation of fungal potentiality for bioconversion of domestic wastewater sludge

This study was undertaken to screen the filamentous fungi isolated from its relevant habitats (wastewater, sewage sludge and sludge cake) for the bioconversion of domestic wastewater sludge. A total of 35 fungal strains were tested against wastewater sludge (total suspended solids, TSS 1%-5% w/w) to evaluate its potentiality for enhancing the biodegradability and dewaterability using liquid state bioconversion(LSB) process. The strains were divided into five groups i. e. Penicillium, Aspergillus, Trichoderma, Basidiomycete and Miscellaneous, respectively. The strains WWZP1003, SCahmA103, SCahmT105 and PC-9 among their respective groups of Penicillium,Aspergillus, Trichoderma and Basidiomycete played potential roles in terms of separation (formation of pellets/flocs/filaments),biodegradation(removal of COD) and filtration(filterability) of treated domestic wastewater sludge. The Miscellaneous group was not considered due to its unsatisfactory results as compared to the other groups. The pH value was also influenced by the microbial treatment during fermentation process. The filterability of treated sludge was improved by fungal treatment, and lowest filtration time was recorded for the strain WWZP1003 and SCahmA103 of Penicillium and Aspergillus groups respectively compared with other strains.     

湿法冶锌废渣中有价金属回收研究进展

综述了电化学法、沉淀法、吸附法、离子交换法、浮选法和液膜分离法等在分离回收湿法冶锌废渣中有价金属及相关领域的研究进展,阐述了吸附法和液膜分离法的原理,指出了湿法冶锌废渣中有价金属回收的研究方向:吸附法拥有巨大的潜力,是今后的研究重点;离子交换法的研究热点是开发新型树脂基体;液膜分离法的研究方向一是提升液膜稳定性,二是研发能够高效单一分离有价金属的载体。     

三种液体稳定剂对过氧乙酸稳定效果的实验研究

利用绝热加速量热仪对三种过氧乙酸液体稳定剂的稳定效果进行了实验分析,并与常规实验方法获得的结论进行了比较。绝热条件下加入三种液体稳定剂后,初始分解温度分别提高了1.85℃、17.52℃和14.73℃,绝热温升分别升高了3.77℃、降低了12.56℃和17.88℃,到达最大温升速率的时间分别延长了508.93min、319.92min和247.92min,稳定效果为磷酸乙酸丁酯磷酸三丁酯,对过氧乙酸的安全生产、储存和使用具有一定指导意义。     

利用Matlab模拟多烟团模式计算危险液体泄漏的研究

关于危险性液体泄漏扩散模型有许多,但是目前常用的主要是比较成熟的高斯模型.在<环境风险评价技术导则>推荐采用的多烟团模式基础上,利用Matlab的可视化界面对变天情况下的多烟团模式模拟某乙醇厂乙醇泄漏,其结果与高斯烟团理论一致.利用该软件,连续输入实际天气情况值,可实时追踪危险性液体在时空中的变化,为环境风险评价管理、风险工程设计、风险责任保险等领域及应急计划制定、事故抢险工作实施提供有效的工具.     

厨余垃圾-蔬菜废物协同生产液肥项目技术经济分析

厨余垃圾-蔬菜废物协同生产液肥项目,需要建立科学、高效的运行管理机制和投入产出机制,以提高其经济效益。系统研究银川市某液肥项目的设备投资和运行费用等情况,目前该项目处理规模约为10.6 t/d,运行负荷率为35.3%,导致处理成本高达337.9元/t。因此,提高运行负荷率,是降低处理成本的关键。     

3,3'-二氯联苯胺盐酸盐合成工业酸性废水中污染物的高效液相色谱法测定

利用高效液相色谱法测定了３,３’－二氯联苯胺盐酸盐合成工业酸性废水中的污染物,色谱柱为Ｚｏｒｂａｘ－ＯＤＳ,流动相为乙腈－水(７０/３０,Ｖ/Ｖ),流速为０．５ｍｌ·ｍｉｎ－１,柱温４２℃,检测波长２８０ｎｍ．建立了废水水样预处理方法,主要污染物回收率在９０%以上．酸性废水中污染物包括３,３'－二氯联苯胺盐酸盐、邻氯苯胺等．     

高效液相色谱法检测与化感现象相关的5种酚酸

建立了香草酸、对羟基苯甲酸、丁香酸、香豆酸和阿魏酸等5种酚酸的高效液相色谱测定方法,利用本方法在土壤溶液和残茬腐解产物中进行5种酚酸的检测,结果表明,大豆生长一段时间后,在灭菌土壤中、未灭菌土壤中和不同茬口的土壤中,均检测到丁香酸,在残茬腐解产物中检测到香草酸、丁香酸、香豆酸和阿魏酸。     

防止大气采样器倒吸装置

在大气采样器上加装防止倒吸装置,可防止吸收液倒吸进入流量计,收集到液的体直观可见,只需将采样管出气口拔掉,倒吸液就会自动流出。