负荷历时曲线法在梁子湖流域污染容量总量控制中的应用

采用负荷历时曲线法(LDC),基于水质保护目标,研究水体纳污能力,确定最大日负荷总量(TMDL)是当前流域污染总量控制的主要方法之一。根据梁子湖高桥河流域控制断面2008~2011年的水文、水质数据,以主要污染物COD为指标,将负荷历史曲线法运用到梁子湖高桥河等子流域污染容量总量控制中,对该流域的最大日负荷(TMDL)变化规律进行分析,提出流域不同水文条件下的污染负荷消减量。研究结果表明:梁子湖水环境受面源污染影响较大。高桥河、徐家港、张家桥港、山坡港、宁港流域,在高流量期实际负荷值均已超出了允许负荷,其削减量分别为61.36、4.33、12.98、3.84、7.13 t/d;徐家港和宁港流域在丰水期实际负荷值也超出了允许负荷,削减量分别为0.16、0.17 t/d。该研究为流域相关管理部门对湖泊水环境的污染控制提供可靠的决策依据。     

The emission patterns of volatile organic compounds during aerobic biotreatment of municipal solid waste using continuous and intermittent aeration

Because volatile organic compounds (VOCs) are one of the main concerns during municipal solid waste (MSW) treatment, the release patterns and the environmental effects of VOCs were investigated during laboratory-scale aerobic biotreatments of MSW with continuous and intermittent negative ventilation. When the same airflow amounts were used, intermittent ventilation was found to reduce the total VOC emissions from continuous ventilation process by 28%. In this study, 23 types of volatile organic compounds were analyzed, of which butyraldehyde, ethanol, and butanone were emitted in the highest concentrations of 748, 372, and 260 mg/m3, respectively. During the aerobic biotreatment process, ketones, aldehydes, and alcohols were primarily released during the first 4 days, accounting for 86-98% of the total VOC emissions during this period. The emission concentrations of malodorous sulfide compounds displayed two peaks on day 4 and day 9, with the contribution to the total VOC emissions being enhanced from less than 10% to 76-83%. The release of terpenes and aromatics lasted for more than 10 days with no significant emission peaks and the proportions of those compounds in the total VOCs increased gradually, but no more than 50% even at the end of the process. Considering the strength of the odors, aldehydes were the predominant contributors at the beginning of the experiment, whereas malodorous sulfide compounds became the most odorous compound as the biological process continued. Most of the VOCs emitted at the concentrations beneath the level causing health threat to the workers.     

好氧颗粒污泥强化解体实验与机理研究

在120r／min的搅拌及pH=1的强酸条件下，进行好氧颗粒污泥的强化解体实验，研究颗粒污泥的总数、平均粒径和粒径分布的变化情况。在15h实验时间内，搅拌强化解体的颗粒平均粒径从1230μm降至320μm，颗粒总数从30个／mL增至193个／mL。强酸强化解体结果类似，但解体时间为110h。搅拌比强酸对颗粒解体的强化作用更明显。粒径分布结果显示，小颗粒所占比例明显增加。颗粒解体过程中粒径分布均符合对数正态分布，但颗粒粒径的期望值石，随解体时间明显减小。根据颗粒的解体机理，即4种解体类型：破碎、破裂、剥落和研磨，结合实验结果，将解体过程分为对数期、平缓期、二次对数期和稳定期。     

二氧化氯应用于二次供水安全消毒的静态研究

采用二氧化氯（ClO2）作为二次供水的消毒剂进行静态实验研究，考察了ClO2投加量、氨氮与CODMn浓度及pH对ClO2衰减及消毒副产物氯酸盐（ClO3^-）和亚氯酸盐（ClO2）的生成影响，并建立了ClO3-和ClO2生成浓度的经验预测模型。结果表明：前4h内，随着消毒剂初始投加浓度提高，ClO2的衰减速率增加，4h后降解则较缓慢。ClO2加入水中，立即有ClO3^-与ClO2^-生成，4h后基本达到稳定，且随着药剂投加量的增加，ClO3^-和ClO2-的生成量逐渐增大。氨氮、CODMn及pH的升高，可加速ClO2的衰减，同时可促进ClO3^-和ClO2-的生成。其中，氨氮浓度从0．085mg／L升高到0．585mg／LClO3^-与ClO2-的生成浓度分别增加了6．49μg／L和8．32μg／L；CODMn从1．13mg／L升高到3．13mg／L，ClO3^-与ClO2-的生成浓度分别增加了13．75μg／L和9．23μg／L；pH从6．49升高到8．45，ClO3^-与ClO2-的生成浓度分别增加了13．28μg／L和10．01μg／L。     

Comparison research on waste classification between China and the EU,Japan, and the USA

Waste and waste management have become significant global issues and common challenges that we face. Efficient and effective waste management is an essential part of civilized society. A good waste classification system is the foundation and precondition for efficient waste management. In this paper, in accordance with waste classification principles of systematicness, hierarchy, practical maneuverability and expansibility, waste classification systems in China, the EU, Japan and the USA are reviewed for collection, transportation and treatment sectors. Comparison analysis results show that waste classification methods are diversified and process-oriented classification, substance-oriented and hazardous properties classification principles are widely adopted for waste generation and transportation. For waste treatment process, all the countries and regions adopt similar classification methods based on follow-up treatment process. In general, the EU and Japan all have established their own integrated waste classification system. However, the EU’s macro–micro integration waste classification systems are more suitable for China to learn which process-oriented waste classification is used for declaration and registration at the micro-level and substance-oriented waste classification system for environmental statistics at the macro-level.     

改性陶粒对水中内分泌干扰物的吸附去除

用CTMAB(十六烷三甲基溴化铵)对陶粒进行改性.实验研究了陶粒改性前后对5种内分泌干扰物EDCs(美托洛尔MTP、磺胺甲噁唑SMZ、卡马西平CBZ、对氯苯氧异丁酸CA、17α-乙炔基雌二醇EE2)的吸附特性.结果表明,CTMAB改性处理对陶粒的孔结构和表面性质都有影响,有效吸附的孔径所占比例和陶粒表面极性升高;室温条件下,EDCs初始浓度和吸附剂浓度均为1 mg/L时,实验用改性陶粒和陶粒达到吸附平衡的时间基本相同,均为5 min左右;改性陶粒能提高大部分EDCs的吸附量,5种内分泌干扰物混合物一起吸附时存在竞争,其中SMZ和MTP竞争力强,CA最弱;吸附机理包括表面物理吸附和分配作用.实验研究拟为改性陶粒应用于水中痕量污染物的处理提供理论依据,支撑保障饮用水处理达标的目的.     

亚临界湿式氧化法脱除含油污泥中的重金属

采用亚临界湿式氧化法及金属络合剂协同亚临界湿式氧化法去除含油污泥中的重金属,考察了去除效果,优化了反应条件,并探讨了脱除重金属的含量上限。实验结果表明:在1 L反应釜内加入200 g含油污泥,在反应温度200℃、反应时间60 min、液固比(去离子水与含油污泥的质量比)0.30的优化条件下,Cu和Zn的去除率分别可达67.3%和22.0%;加入金属络合剂后,各重金属的去除率均有明显提高;在金属络合剂加入量为0.05mol/L的优化条件下,应用金属络合剂协同亚临界湿式氧化法可将2.5倍于CJ/T 309—2009《城镇污水处理厂污泥处置农用泥质》B级标准的重金属含量降至标准范围内。     

全国近岸海域水质空间插值算法精度分析

空间插值技术对近海环境数据的分析和表征具有广泛应用价值,但目前针对各类模型适用性和精度比较的研究很少。基于2009年全国近岸海域299个站位的水质监测数据,利用交叉检验法,对3种插值算法13种模型的空间拟合结果进行分析和验证。结果表明,13种模型的模拟值与实测值显著相关(r=0.643~0.750,P0.01,n=299),说明其均适用于近岸海域水质的空间模拟;综合比较模拟结果与实测结果的相关系数、平均误差、平均绝对误差、均方差及偏离程度,排序为IDW(p2)Spline-TensionIDW(p3)IDW(p4)IDW(p1)IDW(p5)IDW(p6)Kriging-GuassianKriging-Spherical,Kriging-CircularKriging-LinearKriging-ExponentialSpline-Regularized,提出IDW(p2)是精度最优的空间插值模型。     

An investigation of a heat pump system using CO2/propane mixture as a working fluid

In order to decrease the heat rejection pressure of heat pump using pure working fluid, CO₂ or R744, other natural component including hydrocarbons (R290, R600a, R600, R1270, R170, R601) and dimethyl ether (RE170) is added to CO₂, respectively, and then six binary mixtures are achieved. By environmental and thermodynamic comparisons, R290 is selected to be the most appropriate component candidate to mix with CO₂, and meanwhile to weaken the flammability and explosivity for pure R290. Then, the system performances of heat pump using mixture of CO₂ and R290 were experimentally studied when R290 is added to CO₂ with a small fraction, and compared with that of the pure CO₂. The experimental test rig is designed and set up for the transcritical heat pump system. When the refrigerant charge is variable, the heating coefficient performance, optimum heat rejection pressure, compressor power, mass flow rate of refrigerant, and total heat coefficient of gas cooler were researched. The variation ratios of heating coefficient performance and heating capacity with deviation from the optimum refrigerant charge were also investigated. The optimum refrigerant charge of CO₂/R290 is obtained and the research results show that the addition of R290 to CO₂ can efficiently reduce the heat rejection pressure and improve the system performance. The results in the present work could provide useful guidelines for the design and operation of heat pump system using CO₂-based mixture.