高含固污泥水热预处理中碳、氮、磷、硫转化规律

以城市污水处理厂脱水污泥为对象,探讨其在165℃下经50 min水热预处理的碳、氮、磷、硫转化规律.结果表明,水热预处理可有效水解污泥中有机组分,VSS水解率达43.35%.碳、氮、磷、硫在水热预处理过程中表现出不同的转化规律,蛋白质和碳水化合物的水解率分别为54.36%和65.12%,溶解态有机物的主要组分为溶解态蛋白质(52.18%);不溶态有机氮的水解率54.23%,氨氮占溶解态凯氏氮的22.13%,水解液中的氮主要以有机氮形式存在;总磷水解率为30.52%,磷酸盐占溶解态总磷的79.84%,说明在水热预处理过程中聚磷酸盐在聚磷菌细胞破碎后极易被水解为磷酸盐;总硫水解率为50.03%,硫化物占溶解态总硫的0.50%,而有机硫很难水解为硫化物.通过水热预处理后物质转化及组分分析,旨在为高含固污泥有效处理提供一定的理论参考.     

电化学氧化法处理含盐苯醌模拟废水

利用钛基二氧化铅电极(Ti/PbO2)作为电催化活性阳极,通过电化学氧化技术对苯醌进行降解矿化,考察常见共存无机盐对苯醌废水降解效率的影响。结果表明,NaCl存在下苯醌废水溶液的COD去除率相比硝酸盐提高了62%,相比硫酸盐提高了45%,NaCl能够显著增强电氧化去除苯醌的电流效率。苯醌的降解对氯离子非常敏感,存在少量的氯离子即可以引起氧化效率明显增加。氯离子浓度越高,苯醌模拟废水的COD去除率越高;但当氯离子浓度高于0.3 mol·L-1时,COD去除率反而有所下降。pH为8的弱碱性环境更有利于含氯离子苯醌废水的电氧化降解反应。提高电流密度可增大COD去除率;但升高温度会降低COD去除率。在pH为8、NaCl浓度为0.3 mol·L-1、电流密度为10 mA·cm-2、温度为20 ℃的条件下,初始浓度为100 mg·L-1的苯醌经3 h电化学氧化降解后COD去除率可达80.9%。通过高效液相色谱对电氧化降解苯醌的中间产物进行分析,发现氯离子存在下苯醌的降解速度显著提高,中间产物顺丁烯二酸的生成速度更快,这说明由氯离子生成的强氧化剂对苯醌具有极强的开环能力。     

Detection of Phaeocystis globosa using sandwich hybridization integrated with nuclease protection assay (NPA-SH)

Phaeocystis globosa Scherffel is one of the common harmful algae species in coastal waters of the southeastern China. In this study, sandwich hybridization integrated with nuclease protection assay (NPA-SH) was used to qualitatively and quantitatively detect P. globosa. Results showed that this method had good applicability and validity in analyzing the samples from laboratory cultures and from fields. The linear regression equation for P. globosa was obtained, and the lowest detection number of cells was 1.8×104 cells. Statistics showed that there was no distinct difference between the results of detecting the microalgae by NPA-SH and traditional microscopy. This technique has good reliability, accuracy, and can give a remarkably high sample processing rate. Sandwich hybridization integrated with nuclease protection assay will provide an efficient alternative to microscopic method for monitoring and investigating the bloom of P. globosa.     

Characteristics and removal mechanism of the precursors of N-chloro-2,2-dichloroacetamide in a drinking water treatment process at Taihu Lake

• N-Cl-DCAM, an emerging N-DBP in drinking water was investigated. • A new BAC has a better removal efficiency for N-Cl-DCAM precursors than an old BAC. • N-Cl-DCAM precursors are more of low molecular weight and non-polar. • Adsorption of GAC plays a major role in removal of N-Cl-DCAM precursors by an O₃-BAC. N-chloro-2,2-dichloroacetamide (N-Cl-DCAM) is an emerging nitrogenous disinfection by-product (N-DBP) which can occur in drinking water. In this study, an analytical method based on liquid chromatography with tandem mass spectrometry (LC-MS/MS) was developed to validate the concentration of N-Cl-DCAM, which was found to be 1.5 mg/L in the effluent of a waterworks receiving raw water from Taihu Lake, China. The changes of N-Cl-DCAM formation potential (N-Cl-DCAMFP) in the drinking water treatment process and the removal efficiency of its precursors in each unit were evaluated. Non-polar organics accounted for the majority of N-Cl-DCAM precursors, accounting for 70% of the N-Cl-DCAM FP. The effect of conventional water treatment processes on the removal of N-Cl-DCAM precursors was found to be unsatisfactory due to their poor performance in the removal of low molecular weight (MW) or non-polar organics. In the ozonation integrated with biological activated carbon (O₃-BAC) process, the ozonation had little influence on the decrease of N-Cl-DCAM FP. The removal efficiency of precursors by a new BAC filter, in which the granular activated carbon (GAC) had only been used for four months was higher than that achieved by an old BAC filter in which the GAC had been used for two years. The different removal efficiencies of precursors were mainly due to the different adsorption capacities of GAC for individual precursors. Low MW or non-polar organics were predominantly removed by GAC, rather than biodegradation by microorganisms attached to GAC particles.     

废旧电池的回收处理方法比较

废旧电池用完后不加以回收处理，不但对环境严重污染，危害人类健康，而且浪费了宝贵的金属资源，因此，合理回收处理废旧电池，对于环境保护及重金属的回收再生极为重要。本文分析了我国现阶段废旧电池回收处理方法，并与少数发达国家的回收处理方法作比较。     

紫外活化过硫酸钠技术处理水溶液中的1,1,1-三氯乙烷

分别采用不同的紫外光源(UV、VUV)活化Na₂S₂O₈处理水溶液中的TCA(1,1,1-三氯乙烷),考察溶液初始pH、阴离子及HA(腐殖酸)对TCA降解过程的影响. 结果表明:UV/Na₂S₂O₈体系和VUV/Na₂S₂O₈体系中,TCA可分别在60和30 min内完全去除,氧化降解过程符合准一级反应动力学方程,反应动力学常数分别为0.06和0.14 min-1;溶液初始pH越高越不利于TCA的降解;Cl-和HCO₃-的存在能够抑制TCA降解,HCO₃-的抑制效果较Cl-更为显著;ρ(HA)大于10 mg/L时能明显降低TCA的去除率. 2种体系均能使TCA基本脱氯,不产生二次污染.      

生活垃圾焚烧发电碳排放计算方法研究

生活垃圾焚烧发电,利用垃圾焚烧处理的余热发电,在节约能源的同时,也减少了二氧化碳的排放。本文中结合某垃圾焚烧发电无害化处理工程,依据CDM方法学AM0025对该项目的碳减排量进行了计算,结果表明,10a该项目共减少二氧化碳排放量477560t,给我国带来了可观的环境效益和经济效益。     

合金镀铁修复深孔类零件工艺及应用

阐述了对各种深孔类零件内表面磨损以后进行槽外流镀的方法 ,克服了大件及无法绝缘件的镀铁困难问题 ,并确定了最佳工艺过程     

韦伯命题与环境伦理的演变

生态环境问题始终沿着人类社会发展的轨迹演进,探究这一现象背后的精神动因,会发现新教伦理既推动了人类社会的发展,又与人类中心主义的思想渊源相契合,使生态环境状况日益恶化。生态中心主义否定了人类统治自然的合法性,将价值主体沿着新教伦理的逻辑方向扩大到自然,但却忽视了人类在环境演变进程中的能动作用。而人与自然和谐相处的思想则是对人类中心主义和生态中心主义的择优,既张扬了人类的理性和智慧,又承认了自然与人类的平等地位,这是韦伯命题的又一巨大贡献。     

地下车库空气中苯系物浓度的时间分布特征与污染评价

采用气相色谱法定量分析了地下车库空气中苯系物(苯、甲苯、二甲苯)的浓度并于不同时间段采集地下车库的空气样品,研究了地下车库内苯系物的浓度随时间的变化特征及污染状况。研究结果表明:①在实验色谱条件下,用外标法测定苯系物的准确度较高,回收率为90%~110%;②苯系物浓度随时间的变化呈现明显的周期性,苯系物单体浓度与总量浓度随时间的分布特征相似,表现为早晨的浓度大于中午及傍晚;③苯系物总量和单体浓度远远高于室外;④地下车库苯系物浓度低于中国室内空气质量标准限值,但检测结果表明地下车库存在苯系物的污染,长期累积对人体健康构成潜在威胁。