优质页岩陶粒滤料的制备与基本性能研究

以天然页岩为原料,分别采用破碎法和成球法制成滤料生料,经焙烧,膨胀,制备了陶粒滤料.对这2种方法制备的陶粒滤料的孔隙率、孔径和酸碱可溶率等指标进行了分析比较.结果表明,2种方法均可制备出性能优异的陶粒滤料.陶粒滤料的制备方法对其性能影响不大,而焙烧程序对陶粒滤料的性能有较大影响.实际生产时,可根据页岩特性、生产成本等确定陶粒滤料的制备方法.     

粉煤灰/污泥烧结陶粒的研制与应用

以粉煤灰和工业污水处理站的剩余污泥为主要原材料,采用烧结法研制复合陶粒.分析了不同配方和不同烧结温度对陶粒性能的影响,以陶粒吸水率、容重为评价指标确定最佳配比和最佳烧结温度,并对陶粒用于铺设景观水底、治理城市水体进行了可行性分析.粉煤灰/污泥陶粒的容重为0.79～0.90 g/m3,吸水率为68.95%～80.01%.陶粒对水中氨氮和总磷吸附容量分别为0.03～0.05 mg/g和0.01～0.02 mg/g.     

物料下落过程中可吸入颗粒物产生特性及控制技术

利用实验室新设计开发的一套装置,研究物料自由下落过程影响可吸入颗粒物产生的因素.通过实验分别测定不同物料、质量流量、含水量、粒径组成和下垫面5个因素对可吸入颗粒物产生的影响.实验结果表明,不同物料可吸入颗粒物产生率不同;随着质量流量和物料含水量的增加,可吸入颗粒物产生率减小,加水是减少可吸入颗粒物排放的最有效方法之一;不同粒径组成和不同下垫面对可吸入颗粒物产生也有影响,但作用并不显著.     

应用POMS复合膜分离去除废气中挥发性有机污染物

依靠POMS平板单层膜或POMS卷式膜上选择性分离层的选择性溶解和渗透作用,常温负压分离回收废气中乙酸乙酯等挥发性有机污染物(VOC)组分.结果表明,膜两侧操作压差和原料气流量对乙酸乙酯分离效率影响较大;当原料气处理量为1.770 0～2.810 0 m3/(m2·h)、膜两侧操作压差为0.08 MPa,POMS卷式膜乙酸乙酯渗透速率可达7.86 × 10-7 mol/(s·m2·Pa);乙酸乙酯为1 500～4 500 mg/m3时,其去除率可达80%.测得几种VOC组分在POMS复合膜中的溶解吸附量都比较可观,由此预测该膜处理废气中VOC可取得很好的净化效果.甲苯在POMS复合膜中的溶解吸附量低于乙酸乙酯,其实验测得渗透速率也小于乙酸乙酯.甲苯去除率也能达到80%.     

柴油车尾气颗粒物净化用SiC过滤材料的研究与应用

近年来,SiC材料作为一种新型的柴油车尾气颗粒物过滤材料获得了迅速发展,正逐步取代目前广泛应用的堇青石多孔陶瓷材料.结合堇青石和SiC过滤材料的性能特点,重点概述了2种SiC改性过滤材料(重结晶SiC.RSiC和硅结合SiC,Si-SiC)的研究和应用进展,并介绍了SiC颗粒物过滤器的市场现状和发展前景.     

城市垃圾焚烧飞灰重金属药剂配伍稳定化实验研究

以飞灰中富含的Pb和Zn为目标重金属,对飞灰中重金属药剂配伍稳定化效果了实验研究.选用EDTA、Na2S、NaH2PO4等稳定化药剂和pH值控制,首先将试剂单独投加飞灰中测定重金属浸出浓度,分析各试剂的稳定化效果;然后通过系列试验观察现象,确定试剂最优投加顺序;最后,按照试剂性质制定4个配伍方案,按照最优投加顺序投加试剂,测定分析各个配伍方案的稳定化效果.结果表明:pH值保持在弱碱性(10左右),重金属稳定化效果较好.EDTA二钠、NaH2PO4和Na2S重金属稳定化效果明显,而有机试剂EDTA二钠稳定化效果明显优于NaH2PO4和Na2S;稳定化药剂投加顺序以Na2S、EDTA二钠、NaH2PO4顺序投加处理效果为最佳;配伍方案4处理效果明显优于其他方案,可以实现稳定化药剂配伍相合,提高飞灰中重金属稳定化效果,同时减少有机螯合剂的使用量,从而降低处理成本.     

镍、铬对活性污泥真实产率的影响

采用两个直流完全混合式反应器,研究了Ni(Ⅱ) 、Cr(Ⅵ) 对好氧活性污泥真实产率系数(YH)、COD去除率、MLSS和污泥呼吸作用的影响.结果表明,当Ni(Ⅱ) 、Cr(Ⅵ) 为3 mg/L时,YH(MMLSS/MCOD)从无重金属的0.388分别升高到Ni(Ⅱ) 的0.427和Cr(Ⅵ) 的0.408;COD的去除率不受影响,MLSS增加了7.5%;污泥呼吸作用增强了5%.随着Ni(Ⅱ) 、Cr(Ⅵ) 浓度的进一步增加,YH、COD去除率、MLSS和呼吸作用都迅速下降.当Ni(Ⅱ) 、Cr(Ⅵ) 为15 mg/L时,YH(MMLSS/MCOD)分别为0.289和0.218;而Ni(Ⅱ) 、Cr(Ⅵ) 为25 mg/L时,对污泥呼吸的抑制作用分别达43%和60%.总体来看,Cr(Ⅵ) 比Ni(Ⅱ) 对系统的毒性更大.     

微生物絮凝剂的制备及其絮凝活性

从土壤和活性污泥中筛选获得性能稳定、对高岭土悬浮液的絮凝率达75%以上的菌株20株,其中编号为Ⅰ-18的菌株培养液对高岭土悬浮液的絮凝率达85%以上,经鉴定为球形芽孢杆菌Bacillus sphaericus.实验表明,该菌株以质量分数为2%的蔗糖为碳源,以质量分数均为0.15%的蛋白胨与尿素组合为氮源;生长与分泌絮凝剂的合适温度为30℃,适宜的pH为7.0,最佳培养时间为80 h.利用该微生物絮凝剂处理水性油墨废水效果明显,15 min浊度去除率达98.7%.     

微囊藻毒素生物降解的研究进展

蓝藻水华污染造成的最主要危害之一是产生和释放以微囊藻毒素(microcystins,MCs)为主的多种藻毒素,其在饮用水中的存在可以导致人类癌症,因此对人们的健康构成了严重威胁.从MCs降解微生物菌种、酶催化降解途径和降解基因3个方面,介绍了近年来国内外MCs生物降解的研究进展.     

生活垃圾可持续化填埋

通过对中国填埋场现状分析,提出了"可持续填理"的概念.认为生活垃圾填埋场将从单纯的最终处置场所演变为填埋与中转相结合的场所.填埋场的可持续发展也将从两方面得到体现:一为垃圾降解过程及其副产品处理中以能量形式得到利用,另一方面为稳定化后的垃圾及填埋场本身空间得到再一次的利用.     

Sources and fate of PCDD and PCDF

PCDD and PCDF were found in urban air particulates from St. Louis and Washington, D.C., and in sediments from the Great Lakes and Siskiwit Lake, Isle Royale. The similarity between the PCDD and PCDF found in air particulates and sediment samples and the presence of PCDD and PCDF in sediment from Siskiwit Lake (a location which can receive only atmospheric inputs) suggest that these compounds are emitted to the atmosphere from combustion sources. The historical input of PCDD and PCDF to dated sediment cores shows a strong increase since 1940, and this suggests that the incineration of chlorinated organic compounds is an important source of PCDD and PCDF to the environment.     

Meta-analysis of time-series studies of air pollution and mortality: effects of gases and particles and the influence of cause of death,age, and season

A comprehensive, systematic synthesis was conducted of daily time-series studies of air pollution and mortality from around the world. Estimates of effect sizes were extracted from 109 studies, from single- and multipollutant models, and by cause of death, age, and season. Random effects pooled estimates of excess all-cause mortality (single-pollutant models) associated with a change in pollutant concentration equal to the mean value among a representative group of cities were 2.0% (95% CI 1.5-2.4%) per 31.3 microg/m3 particulate matter (PM) of median diameter < or = 10 microm (PM10); 1.7% (1.2-2.2%) per 1.1 ppm CO; 2.8% (2.1-3.5%) per 24.0 ppb NO2; 1.6% (1.1-2.0%) per 31.2 ppb O3; and 0.9% (0.7-1.2%) per 9.4 ppb SO2 (daily maximum concentration for O3, daily average for others). Effect sizes were generally reduced in multipollutant models, but remained significantly different from zero for PM10 and SO2. Larger effect sizes were observed for respiratory mortality for all pollutants except O3. Heterogeneity among studies was partially accounted for by differences in variability of pollutant concentrations, and results were robust to alternative approaches to selecting estimates from the pool of available candidates. This synthesis leaves little doubt that acute air pollution exposure is a significant contributor to mortality.     

Meta-Analysis of Time-Series Studies of Air Pollution and Mortality: Effects of Gases and Particles and the Influence of Cause of Death,Age, and Season

Abstract

A comprehensive, systematic synthesis was conducted of daily time-series studies of air pollution and mortality from around the world. Estimates of effect sizes were extracted from 109 studies, from single- and multipollutant models, and by cause of death, age, and season. Random effects pooled estimates of excess all-cause mortality (single-pollutant models) associated with a change in pollutant concentration equal to the mean value among a representative group of cities were 2.0% (95% CI 1.5-2.4%) per 31.3 μg/m³ particulate matter (PM) of median diameter <10 μm (PM₁₀); 1.7% (1.2-2.2%) per 1.1 ppm CO; 2.8% (2.1-3.5%) per 24.0 ppb NO₂; 1.6% (1.1-2.0%) per 31.2 ppb O₃; and 0.9% (0.7-1.2%) per 9.4 ppb SO₂ (daily maximum concentration for O₃, daily average for others). Effect sizes were generally reduced in multipollutant models, but remained significantly different from zero for PM₁₀ and SO₂. Larger effect sizes were observed for respiratory mortality for all pollutants except O₃. Heterogeneity among studies was partially accounted for by differences in variability of pollutant concentrations, and results were robust to alternative approaches to selecting estimates from the pool of available candidates. This synthesis leaves little doubt that acute air pollution exposure is a significant contributor to mortality.     

Field and laboratory studies of the fate and enantiomeric enrichment of venlafaxine and O-desmethylvenlafaxine under aerobic and anaerobic conditions

The stereoselectivity of R,S-venlafaxine and its metabolites R,S-O-desmethylvenlafaxine, N-desmethylvenlafaxine, O,N-didesmethylvenlafaxine, N,N-didesmethylvenlafaxine and tridesmethylvenlafaxine was studied in three processes: (i) anaerobic and aerobic laboratory scale tests; (ii) six wastewater treatment plants (WWTPs) operating under different conditions; and (iii) a variety of wastewater treatments including conventional activated sludge, natural attenuation along a receiving river stream and storage in operational and seasonal reservoirs. In the laboratory and field studies, the degradation of the venlafaxine yielded O-desmethylvenalfaxine as the dominant metabolite under aerobic and anaerobic conditions. Venlafaxine was almost exclusively converted to O-desmethylvenlafaxine under anaerobic conditions, but only a fraction of the drug was transformed to O-desmethylvenlafaxine under aerobic conditions. Degradation of venlafaxine involved only small stereoisomeric selectivity. In contrast, the degradation of O-desmethylvenlafaxine yielded remarkable S to R enrichment under aerobic conditions but none under anaerobic conditions. Determination of venlafaxine and its metabolites in the WWTPs agreed well with the stereoselectivity observed in the laboratory studies. Our results suggest that the levels of the drug and its metabolites and the stereoisomeric enrichment of the metabolite and its parent drug can be used for source tracking and for discrimination between domestic and nondomestic wastewater pollution. This was indeed demonstrated in the investigations carried out at the Jerusalem WWTP.     

Sorption and desorption of Cu and Cd by macroalgae and microalgae

The sorption and desorption of Cu and Cd by two species of brown macroalgae and five species of microalgae were studied. The two brown macroalgae, Laminaria japonica and Sargassum kjellmanianum, were found to have high capacities at pHs between 4.0 and 5.0 while for microalgae, optimum pH lay at 6.7. The presence of other cations in solution was found to reduce the sorption of the target cation, suggesting a competition for sorption sites on organisms. Sorption isotherms obeyed the Freundlich equation, suggesting involvement of a multiplicity of mechanisms and sorption sites. For the microalgae tested, Spirulina platensis had the highest capacity for Cd, followed by Nannochloropsis oculata, Phaeodactylum tricornutum, Platymonas cordifolia and Chaetoceros minutissimus. The reversibility of metal sorption by macroalgae was examined and the results show that both HCl and EDTA solutions were very effective in desorbing sorbed metal ions from macroalgae, with up to 99.5% of metals being recovered. The regenerated biomass showed undiminished sorption performance for the two metals studied, suggesting the potential of such material for use in water and wastewater treatment.     

Sources and distribution of polychlorinated-dibenzo-p-dioxins and -dibenzofurans in soil and sediment from the Yellow Sea region of China and Korea

Polychlorinated-dibenzo-p-dioxins and -dibenzofurans (PCDD/Fs) were measured in soils and sediments from the Yellow Sea region. Korean soils and sediments mostly contained detectable PCDD/Fs and showed a widespread distribution among locations. Soil and sedimentary PCDD/Fs from China were comparable to or less than those in Korea. The patterns of relative concentrations of individual congeners in soils were different between the two countries, but similar in sediments. Sources of PCDD/Fs in China and Korea were found to be independent of each other and their distributions reflected matrix-dependent accumulation. Spatial distribution indicated some point sources in Korea while Chinese sources were more widespread and diffuse. PCDD/Fs measured in the coastal areas of the Yellow Sea were comparable to or less than those previously reported in for eastern Asia. However, ∑TEQs in soils and sediments were near to or, in some cases exceeded environmental quality guidelines.     

剩余污泥浓缩脱水投药量优化和模型建立

应用高分子阳离子絮凝剂（CPF-100）和聚丙烯酰胺（PAM）对污水厂剩余污泥进行浓缩脱水实验，研究表明：CPF-100的浓缩脱水效果优于PAM；当CPF-00投加量为1．16‰时，污泥沉降性能改善程度为37．51％；且在CPF-100投加量逐渐增大的初始阶段，污泥沉降性能改善程度随投加量的增加而增大，但CPF-100投加量也不宜过大，当CPF-100投加量超过1．16‰后，反而会使浓缩脱水效果变差。同时，建立了污泥沉降性能改善程度与絮凝剂CPF-100投加量、沉降时间之间的数学模型，其能较好地反映污水厂剩余污泥的浓缩脱水效果。     

Experimental and statistical validation of SPME-GC-MS analysis of phenol and chlorophenols in raw and treated water

A procedure based on solid-phase microextraction (SPME) and gas chromatography coupled with mass spectrometry (GC-MS) was developed and validated in order to analyse 10 phenols in water samples. The optimised conditions were obtained using polyacrylate fibre (PA), 20ml of sample volume, 10% NaCl, pH 4.0 and direct extraction at 35 degrees C and 1000rpm, for 40min. The linear range and quantification limits for these compounds by SPME-GC-MS were defined. An evaluation of the main uncertainty sources of this method is included, which allows expanded uncertainties in the 9.4-35% range for the majority of the compounds. The main source of uncertainty is associated with matrix effects. The validated method is suitable for monitoring the production and distribution of potable water and was used, in field trials, for the analysis of samples from main intakes of water (surface or underground) and from water supply system of a large area (Lisbon and neighbour municipalities).     

骆马湖富营养化和生态状况调查与评价

为了了解骆马湖水质状况，在2005年对骆马湖富营养化状态和生态特性进行了调查，并结合“十五”期间的监测资料进行了分析。2005年骆马湖水体中总氮和总磷的平均值超《地表水环境质量标准》（GB3838-2002）中Ⅲ类，超标情况分别为0．78倍和0．54倍，达到湖库特定项目Ⅳ类水标准，骆马湖处于轻度富营养化状态。对骆马湖生态特征分析表明，由于该湖泊的形态以及“藻型浊水状态”和“泥沙型浊水状态”交替出现，遏制了湖水从高营养盐含量向全面富营养化状态演变，保障了底栖动物的良好生长环境，从而形成了骆马湖独特的环境生态平衡。