连续流反应器中培养好氧颗粒污泥的运行效能研究

在连续流完全混合反应器(CSTR)中,采用不同进水方式,以乙酸钠作为碳源配制的人工配水作为原水,对好氧颗粒污泥的运行效能进行了试验研究。研究表明,采用不同进水方式运行的2个反应器在颗粒污泥出现后,运行效能差别不大;好氧颗粒污泥反应器运行高效稳定,在水力停留时间为1.5h、COD容积负荷为1.0kg/(m3·d)的条件下,对COD、TP、NH4+-N和TN的去除率分别为90%、85%、95%和60%,并具有明显的脱氮除磷效果;反应器中存在同步硝化反硝化现象。     

生物转鼓过滤器反硝化净化NO的效率研究

采用自行研制的生物转鼓过滤器(RDB)反硝化净化NO。结果表明,在实验温度为25～30℃、pH为7.0～7.5、转鼓转速为1.0r/min、空床停留时间(EBRT)为86.40s、营养液用量为5.0L、营养液更换频率为0.2L/d的条件下,RDB在30d内完成挂膜;RDB稳定运行期间,当NO进气质量浓度为90～433mg/m3时,NO去除率维持在42.9%～85.2%,平均去除负荷为10.40g/(m3.h);转鼓转速决定了生物膜表面的更新速率和液膜厚度,当转速为0.5r/min时,NO去除率达到最大值(75.0%);将营养液用量控制在1.3～3.0L较为合理;EBRT是决定反硝化效率的重要因素,当EBRT为345.60s时,NO去除率不受其进气浓度的影响,且去除率高达95%以上,当EBRT为43.20s、NO进气质量浓度从98mg/m3增加到1095mg/m3时,NO去除率从62.5%下降到30.7%,当进气负荷为50.00g/(m3.h)时,NO去除负荷达到最大值(27.50g/(m3.h))。     

低浓度Pb2+、Cd2+对鲫鱼肝脏组织中 HSP70诱导的影响

以鲫鱼(Carassius auratus)作为实验对象,经过40 d Pb2+、Cd2+不同浓度的暴露后,运用SDS-PAGE和Western Blotting方法检测鱼肝脏组织内应激蛋白HSP70的诱导表达情况.结果表明,在实验浓度下,与对照组相比,Pb2+、Cd2+对鱼肝脏内HSP70有显著的诱导(P＜0.05),但在Cd2+浓度为0.2 mg/L有停止表达HSP70的现象,可能是由于浓度过高造成了组织病理损伤而破坏了诱导表达机制.实验还发现,在实验浓度低于国家渔业用水标准时,HSP70仍然表现为明显诱导(P＜0.05),充分说明运用分子生物学指标要比传统的环境检测指标敏感,具有对污染物早期预警的作用.     

壬基酚及其短链聚氧乙烯醚在污泥和土壤中的存在和降解

壬基酚聚氧乙烯醚(NPnEO)是广泛使用的表面活性剂．在污水处理厂中会降解为具有内分泌干扰效应的短链产物和最终产物壬基酚(NP)。剩余污泥是其进入环境的重要途径。介绍了NP和短链NPnEO在污泥中的存在情况、污泥处理过程对其存在的影响、以及这些物质随污泥处置过程进入土壤后的降解。     

垃圾填埋场对地下水污染的模拟研究

在对长春市某垃圾填埋场进行野外调查的基础上 ,于室内进行了垃圾淋滤模拟实验。分析了垃圾渗滤液污染组分的自然衰减规律 ,建立了垃圾填埋场地下水污染的数值模型 ,采用FEFLOW软件对其进行模拟和预报 ,并取得了较好的效果 ,最后提出防止和防治垃圾填埋场污染地下水的若干措施。     

SBR处理生活污水好氧颗粒污泥的培养研究

采用SBR,以生活污水为进水,在常温条件下,接种苏州某污水厂活性污泥,对好氧颗粒污泥进行培养,并对反应器的运行效能进行了研究。研究表明,经100多天的运行,培养出粒径在4~8 mm间,结构松散,外观灰白色的好氧颗粒污泥;用城市生活污水培养的颗粒污泥对污染物的去除效果不好,无明显的脱氮除磷能力。     

UV-Fenton体系预处理四氢呋喃废水实验研究

采用UV-Fenton体系预处理四氢呋喃废水,实验结果表明,pH值、反应时间、Fe2+和H2O2投加量等因素对处理效果有较大的影响。实验确定的最佳反应条件为:原水pH=5,Fe2+投加量2.5 mmol/L,H2O2投加量12 mmol/L,反应时间90 min,连续曝气,在此条件下,COD去除率可达85%左右。经UV-Fenton体系处理后,废水的B/C值由0.16增至0.47,可生化性提高,可满足后续生化处理的要求。     

无硫膨胀石墨的制备及吸油性能

通过单因子实验考察了无硫膨胀石墨制备过程中氧化剂及插层剂用量、氧化反应及插层反应时间、氧化反应及插层反应温度对无硫膨胀石墨膨胀体积的影响。通过正交实验确定了制备无硫膨胀石墨的最优条件是:石墨(g)∶浓硝酸(mL)∶30%H2O2(mL)∶乙酸酐(mL)=1∶2.25∶0.25∶0.6,在30℃条件下氧化反应60 min,加入插层剂后在60℃条件下插层反应90 min,此条件无硫膨胀石墨的膨胀体积达317 mL/g使用XPS、FT-IR、XRD和SEM对无硫膨胀石墨进行了表征并对其吸油性能和再生性能进行了研究。结果表明,所制备无硫膨胀石墨对原油和柴油的最大吸附量分别为66.3 g/g和62.7 g/g。吸附原油后的无硫膨胀石墨抽滤再生后首次再生率为49.1%,原油的回收率为64.5%。     

Polychlorinated dibenzo-p-dioxins, dibenzofurans and polychlorinated biphenyls levels in human breast milk from different regions of Turkey

Human breast milk offers the optimal nutrition for all infants and have been widely used in biomonitoring programs to assess human exposure to lipophylic environmental contaminants such as polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and polychlorinated biphenyls (PCB). There are no previous reports from Turkey on chemically determined levels of PCDDs, PCDFs, and PCBs in human breast milk expressed as World Health Organization (WHO) toxic equivalents (TEQ). To get an overview of the levels of these contaminants in Turkish human milk, samples from 51 Turkish women living in the Ankara, İstanbul, Antalya, Kahramanmaraş, and Afyon provinces were analyzed by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) throughout 2007. The mean concentrations of WHO_PCDD/F-TEQ and WHO_PCB-TEQ of all samples from the five regions were 7.5 and 3.1 pg g⁻¹ on a lipid basis, respectively. PCDD/F concentrations ranged between 0.78 and 29.3 pg WHO-TEQ g⁻¹ fat (1.7 and 36.2 pg WHO-TEQ g⁻¹ fat, respectively, including PCB). Of the five studied locations, the lowest levels of ∑TEQs (PCDD/F + PCB) were found in the Afyon (6.8 pg WHO-TEQ g⁻¹ fat) and the highest in the Antalya (15.6 pg WHO-TEQ g⁻¹ fat) province. The results have been discussed in terms of regions and PCDD/F and PCBs for which analyses had been made. The mean levels of PCDD/Fs and PCBs in Turkish human milk are comparable to that found in other countries.     

Temporal dimension and water quality control in an emission trading scheme based on water environmental functional zone

Emission trading is one of the most effective alternatives to controlling water pollution. Water environmental functional zone (WEFZ) is used to determine the water quality standard and identify the zone boundary for each river or reach. In this study, a new emission trading scheme was addressed based on WEFZ, accounting for both the temporal dimension and water quality control. A temporal factor of emission trading was proposed based on variations in the environmental capacity within a year by dividing the year into three periods, including high, normal, and low periods of environmental capacity. During each period, emission trading was implemented exclusively. A water quality-control scheme was suggested based on the water quality requirement in the water functional zone, in which the water quality at the downstream boundary of the zone was required to meet the water standard following auto-purification in the stream. Two methods of calculating water quality control are addressed for point-source pollution and non-point-source pollution. The calculated temporal dimension and water quality control were located in Dongxi River of the Daning Watershed in the Three Gorges Watershed. The high period was during June, July, and August, the normal period was during April, May, September, and October, and the low period was during January, February, March, November, and December. The results from the water quality calculation demonstrated that the discharge of point-source and non-point-source pollutions led to an excess of common contaminants at the downstream boundary of WEFZ. The temporal and spatial factors above should be incorporated into the emission trading scheme based on WEFZ.