Estimation of apparent rate coefficients for phenanthrene and pentachlorophenol interacting with sediments

To gain information on organic pollutants in water-sediment systems, a compartment model was applied to study the sorption course of phenanthrene and pentachlorophenol (PCP) in sediments. The model described the time-dependent interaction of phenanthrene and PCP with operationally defined reversible and irreversible (or slowly reversible) sediment fractions. The interactions between these fractions were described using first order differential equations. By fitting the models to the experimental data, apparent rate constants were obtained using numerical optimization software. The model optimizations showed that the amount of reversible phase increased rapidly in the first 10 d with the sorption time, then decreased after 10 d, while the amount of irreversible phase increased in the total sorption course. That suggested the mass transport between reversible phase and irreversible phase. The extraction efficiency with hot methanol ranged from 36% to 103% for phenanthrene and from 65% to 101% for PCP, with the trend of decreasing with sorption time.     

高氨氮对厌氧生物法处理城市垃圾渗沥液的影响

研究了高浓度氨氮对厌氧膜生物法处理城市垃圾渗沥液的影响。结果表明，COD去除率、沼气产量、沼气产率、辅酶F420和最大比产甲烷活性均随氨氮浓度的增加而减小；当氨氮浓度〈3600mg/L时，不会对厌氧膜生物反应器的运行产生明显的影响；氨氮对厌氧污泥产甲烷活性的50％抑制浓度为4350mg／L；高浓度氨氮会造成系统VFA浓度增加；当氨氮浓度由4800mg／L降低到2000mg/L后，受重度抑制的厌氧微生物的活性可以在20d里恢复到未受抑制时的活性水平。     

影响活性污泥脱氮效率的因素

活性污泥对氮的去除主要通过硝化和反硝化作用来进行。温度、pH、溶解氧浓度、污泥龄、毒性物质、污水性质(有机物含量、氮浓度)都会对系统脱氮能力产生影响。一般较高的pH、延长污泥龄、较低的溶解氧浓度和较低的有机碳浓度均能提高系统的硝化能力,反硝化/硝化系统具有投资省、脱氮效率高等优点。除甲醇外,其它一些工业废弃物也可作为促进反硝化作用的碳源。由于厌氧环境有利于反硝化作用,所以厌氧/好氧(A/O)法和间歇式活性污泥法(SBR)具有极高的脱氮效率。     

石油污染土壤生物通风修复及其强化技术

处理石油污染土壤的诸多方法中 ,生物通风法是一种很有效的治理方法。本文通过对生物通风法的技术、经济分析 ,得出该方法的可行性。另外 ,还介绍了生物通风的强化技术。     

医疗废物中有机质的热解动力学研究

在空气气氛下,对医疗废物中几种有代表性的有机质进行非等温热解实验。分析实验结果发现,热解失重曲线与N2气氛下不同,出现多个DTG峰。利用Freeman Carroll法求出了各有机质的表观动力学参数,并建立了能较好反映各物料失重过程的表观多步反应动力学模型。针对混合物料无法直接求出表观动力学参数,建立了多组分反应动力学模型。     

新型湿式湍流除尘器及在电厂输煤系统中的应用

介绍了针对火电厂输煤系统作业环境粉尘治理而研制开发的新型湿式湍流除尘器的设计思路、设备结构、技术特点及在电厂输媒系统的应用情况。     

Shifted power-law relationship between NO2 concentration and the distance from a highway: A new dispersion model based on the wind profile model

In this paper, a shifted power-law model, based on the wind profile model, had been supposed to simulate concentration gradient of nitrogen dioxide (NO₂) with distance from a highway. Field experiments were performed for NO₂ gradients from a highway in Shanghai by using passive samplers. The shifted power-law model was fitted well with experimental results of field experiments both in this study and in the literature. The results not only verified the validity of shifted power-law relationship between NO₂ concentration and the distance from a highway, but also partially demonstrated that there were some significant similarities between wind profile and air pollutants concentration profile near highway. With known concentration of chosen reference point and appropriate value of the parameter k, the model could be practically applied for predicting the NO₂ distributions near a highway. The methods of determining the parameter k were also discussed for further detailed studies.     

医疗废物中有机质的热解动力学研究

在空气气氛下，对医疗废物中几种有代表性的有机质进行非等温热解实验。分析实验结果发现，热解失重曲线与N2气氛下不同，出现多个DTG峰。利用Freeman—CarroⅡ法求出了各有机质的表观动力学参数，并建立了能较好反映各物料失重过程的表观多步反应动力学模型。针对混合物料无法直接求出表观动力学参数，建立了多组分反应动力学模型。     

水解-酸化法在味精废水处理中的应用

结合江苏南通天字味精厂的工程实例,介绍了以水解-酸化法为主体的味精废水处理工艺的原理、特点和应用中注意的问题.该工艺运行结果表明:在治理味精废水方面具有较佳的耐冲击性能;出水稳定达标;操作运行管理方便;投资成本和运行费用均较低.从其优势看有良好的应用前景.     

交联聚乙烯亚胺螯合树脂对锌离子的吸附研究

以聚丙烯腈 (PAN)大孔树脂为载体 ,将活性组分聚乙烯亚胺 (PEI)通过化学涂敷手段交联在其表面 ,制备出一种新型交联螯合树脂。本文考察了此树脂对溶液中锌离子的吸附性能 ,开展了饱和吸附容量、等温吸附曲线、pH影响曲线以及吸附速度曲线等实验。结果表明 ,此交联螯合树脂具有对锌离子吸附能力强、吸附速度快等特点 ,可望用于含锌废水的处理及回收。