进口含对苯二甲酸物品的固体废物属性鉴别方法研究

基于已完成的40余例进口含对苯二甲酸物品的固体废物属性鉴别实践,系统地介绍了所遇到的进口含对苯二甲酸物品的申报品名、每种品名所占的比例、种类以及每种种类的特征、属性鉴别的关键方法。结果表明,对于不同含对苯二甲酸物品种类的鉴别,应以得出是否为可进口的固体废物为目的,抓住关键点进行鉴别。其中申报品名主要为对苯二甲酸次级品或副牌,所占比例为42.9%;鉴别结果主要为水池料,所占比例为50.0%。     

餐饮垃圾主要成分的热解动力学研究

将餐饮垃圾的主要成分纤维素、淀粉以及脂肪分别在10 K/min的升温速率下进行TG-DTG分析,结果表明3种物质由于分子结构与物质组成的差别,其热解特性有着明显的不同;同时采用Achar(微分法)和Coats-Refern(积分法)相结合的方法对餐饮垃圾进行热解动力学分析,找出最佳的机理函数并求出每种组分的活化能Ea和指前因子lnA。     

进口粉末涂料物品的固体废物属性鉴别方法研究

基于已完成的90余例进口粉末涂料物品固体废物属性的鉴别实践,系统介绍了所遇到的进口粉末涂料物品的申报品名、每种品名所占的比例、种类以及每种种类的特征、固体废物属性鉴别的关键方法和所占的比例,其中申报品名主要为粉末涂料,所占比例为46.3%;鉴别结果主要为过期粉或者不合格粉,所占比例为41.8%。为进口粉末涂料物品的固体废物属性鉴别和监管提供参考,对将无法再生利用的废粉末涂料固体废物堵在国门之外具有重要意义。     

一种新的水质评价方法

每种水质评价方法的运用都离不开水质标准的正确选用。本文提出的一种新的水质评价方法,旨在使评价结果与国内现行的水质标准相吻合,同时,又能反映出被评价的水质所属其类别的程度。     

正渗透膜技术的研究与应用进展

近年来,正渗透膜技术因低能耗、低污染、污染物截留能力强等优势已成为国内外研究的热点之一。首先介绍了正渗透膜技术中膜材料和汲取液的研究现状,比较了醋酸纤维(CTA)膜、薄层复合(TFC)膜与新型水通道蛋白(AQP)仿生膜的性能及优缺点,综述了汲取液的种类及对应的回收方法;其次,对正渗透膜污染机理进行了分析,并总结了针对每种污染的清洗措施;此外,将正渗透膜技术在产能、水资源回收等领域的应用研究现状进行了归纳;最后,基于以上论述进行了总结,对正渗透膜的未来研究方向进行了展望。     

基于ASM2D模型对奥贝尔氧化沟工艺的模拟研究

基于活性污泥数学模型ASM2D,对西安市某污水厂奥贝尔氧化沟工艺进行模拟研究。根据实际工艺构建模型,输入实测模型组分与模型参数。参照实测出水水质对所建模型进行校准与验证。之后,通过调节污泥回流比与BOD5污泥负荷对氧化沟工艺进行优化,使其取得更好的污染物去除率。     

基于CFD的两种紫外消毒模型的比较研究

为了预测紫外反应器的消毒效率,提高模拟的准确度,对两种紫外光强模型进行了比较分析。利用CFD技术,采用数值模拟的方法,对线源和柱源两种光强模型进行了光强分布以及消毒效率的模拟,并采用生物实验进行了验证。结果表明:与柱源模型相比,线源模型在近灯管处强度高42.3%,在1.2 cm处二者趋于一致;针对同一管式紫外反应器,透光率为95%时,线源模型的模拟结果偏大,柱源结果偏小;透光率为80%时,线源及柱源模型的模拟结果都偏大,流量及模型影响较小,透光率成为主要影响因素。综合比较,柱源模型适用于小型管式紫外灯消毒数值模型的开发。     

碱式硫酸铝溶液吸收二氧化硫

为了探讨碱式硫酸铝对二氧化硫的吸收效果，对所需试剂硫酸铝和碳酸钙的适宜比例（碱度），以及碱式硫酸铝能稳定存在的铝量范围等进行了研究，测定了不同铝量和碱度的碱式硫酸铝对二氧化硫的吸收量以及pH值，并分析每种吸收液的饱和吸收量，最后将其与乙二胺/磷酸溶液的吸收情况进行对比。结果表明，碱度为40%时，铝量要保持在70 g/L以下才能在加热时不产生沉淀，吸收过程pH由4.5左右一直下降到2.0左右保持稳定，饱和吸收时间控制在140~160 min为宜，较为理想的方案是铝量32 g/L，碱度35%。     

基于最佳聚类数的水环境生态补偿标准研究

在污染治理成本法确定生态补偿标准已有研究的基础上,对大样本重叠数据进行最佳聚类分析,以聚类后的样本数据建立拟合曲线模型,并对建立的模型方程进行统计检验,通过统计检验的方程确定为核算生态补偿标准的模型方程.同时,以河南省辖淮河流域63座城市污水处理厂数据进行实证分析,在确定最佳聚类分组后,采用SPSS软件进行曲线拟合,并对拟合的方程进行检验和选择,最终确定生态补偿标准.     

非点源污染负荷估算方法研究进展及对北京市的应用

非点源污染是目前影响北京市水环境质量的主要污染源之一,对国内外水环境非点源污染负荷估算方法的研究进展及应用情况进行了总结和分析,介绍了污染负荷当量法、径流分割法、经验相关关系法等经验统计方法,并重点对SWMM模型、输出系数模型等模型估算方法的原理、特点及对北京市的应用情况进行了概括分析。     

Biodegradation and bio-sorption of antibiotics and non-steroidal anti-inflammatory drugs using immobilized cell process

In the present study, the removal mechanisms of four antibiotics (sulfamethoxazole, sulfadimethoxine, sulfamethazine, and trimethoprim) and four non-steroidal anti-inflammatory drugs (acetaminophen, ibuprofen, ketoprofen, and naproxen) in immobilized cell process were investigated using batch reactors. This work principally explores the individual or collective roles of biodegradation and bio-sorption as removal routes of the target pharmaceuticals and the results were validated by various experimental and analytical tools. Biodegradation and bio-sorption were found as dominant mechanisms for the drug removal, while volatilization and hydrolysis were negligible for all target pharmaceuticals. The target pharmaceuticals responded to the two observed removal mechanisms in different ways, typically: (1) strong biodegradability and bio-sorption by acetaminophen, (2) strong biodegradability and weak bio-sorption by sulfamethoxazole, sulfadimethoxine, ibuprofen and naproxen, (3) low biodegradability and weak bio-sorption by sulfamethazine and ketoprofen, and (4) low biodegradability and medium bio-sorption by trimethoprim. In the sorption/desorption experiment, acetaminophen, sulfamethoxazole and sulfadimethoxine were characterized by strong sorption and weak desorption. A phenomenon of moderate sorption and well desorption was observed for sulfamethazine, trimethoprim and naproxen. Both ibuprofen and ketoprofen were weakly sorbed and strongly desorbed.     

Chemical degradation and biodegradability increase

The mill waste water holds a large amount of polyphenols, preventing the biodegradation processes because of their inhibitory action on microbial growth. Thus, its disposal represents an environmental problem for the great olive oil producing countries in the Mediterranean area. In this work, we present the preliminary results from the application of a photo-oxidative process on mill waste water to evaluate the organic matter degradation potential and the biodegradability of the treated residue. The total organic carbon is reduced up to 35% after 6 hours but the cost-effectiveness is unfavourable. In contrast, the aim of toxicity reduction is less expensive and shows good applicable chances; after 2 h, the polyphenols concentration drops by 60%.     

The Use of Parametric Statistics id Biological Treatability Studies

Conclusions concerning the biodegradability of contaminants in samples from a given site are drawn from biological treatability studies. These conclusions are reached on the basis of statistical comparisons of time-dependent, contaminant-reduction data between biologically active and inhibited control samples. Several statistical methods are applicable to analyze such data, but some frequently used statistical procedures lead to bias in the interpretation of results. This paper discusses the appropriateness of various statistical models for determining the significance of biotreatability study results.     

Laboratory simulation of biodegradation of chemicals in surface waters: closed bottle and respirometric test

Microbial degradation is the most dominant elimination mechanism of organics from the environment. For evaluation of biodegradability of pure chemicals many standardized tests are available, but no standardized procedure for assessment of biodegradability of chemicals in surface water is agreed upon. Rates of in-situ biodegradation are usually estimated in laboratory simulation where environmental factors are reproduced to some extent. The aim of our study was to compare standardised ready biodegradability assessment, test (Closed bottle test) and its modifications employing the basic agreements on test conditions to simulate biodegradation in surface water. Standard test was modified using various natural river waters to simulate the natural environment in a simplified way. The impact of different types and amounts of nutrients and microorganisms on biodegradation was confirmed. The conditions in the recipient should be examined to extrapolate the results from ready biodegradability tests to real surface water.     

Fenton试剂-石灰法预处理土霉素废水

采用Fenton试剂-石灰法预处理土霉素废水,结果表明,在适宜条件下对不同浓度的废水进行处理,CODcr去除率可达71％以上,废水的可生化性(BOD5／CODcr)由0．1提高到0．4以上;实验还对土霉素纯品进行处理,通过对处理前后的Uv—Vis光谱分析证实了彻底去除土霉素是废水可生化性提高的主要原因。     

Modeling and interpreting bioavailability of organic contaminant mixtures in subsurface environments

Bioavailability often controls the fate of organic contaminants in surface and subsurface aquatic environments. Bioavailability can be limited by sorption, mass transfer, and intrinsic biodegradation potential and can be further altered by the presence of other compounds. This paper reviews current perspectives on the processes influencing subsurface contaminant bioavailability, how these processes are modeled, and how the relative role of the various processes can be assessed through bioavailability indices. Although these processes are increasingly well understood, the use of sophisticated models and indices often are precluded by an inability to estimate the many parameters that are associated with complex models. Nonetheless, the proper representation of sorption, mass transfer, biodegradation, and co-solute effects can be critical in predicting bio-attenuation. The influence of these processes on contaminant fate is illustrated with numerical simulations for the simultaneous degradation of toluene (growth substrate) and trichloroethylene (nongrowth cometabolite) in hypothetical, aerobic, solid-water systems. The results show how the relative impacts on contaminant fate of the model's various component processes depends upon system conditions, including co-solute concentrations. Slow biodegradation rates increase the inhibition effects of a cometabolite and suppress the rate enhancement effects of a growth substrate. Irrespective of co-solute effects, contaminant fate is less sensitive to biodegradation processes in systems with strong sorption and slow desorption rates. Bioavailability indices can be used to relate these findings and to help identify appropriate modeling simplifications. In general, however, there remains a need to redefine such indices in order that bioavailability concepts can be better incorporated into site characterization, remediation design, and regulatory oversight.     

Evaluation of laboratory-made sludge for an anaerobic biodegradability test and its use for assessment of 13 chemicals

Laboratory-made sludge for a biogas based anaerobic biodegradability test was prepared as an alternative for digested sludge from wastewater treatment plants (WWTPs). Biodegradation activities and background gas productions of digested sludge from various WWTPs were found to vary significantly depending on the source, which adversely affected test reliability. Subsequently, test conditions such as sludge concentration and sludge washing were examined with the laboratory-made sludge and a sludge concentration of 1.0 g-SS/L without washing was determined to be most suitable. Under these conditions, biodegradability tests were conducted for 13 select chemicals and their relative toxicities to methanogenic bacteria were evaluated. The results of biodegradability tests showed that chemicals with -OH and -CH2OH radicals were readily biodegraded and those with -Cl, -NO2, -NH2, -SO3H and -CH3 had inhibited degradation responses m-nitriphenol and 2,4,6-trichlorophenol were highly toxic to methanogenic bacteria, with m-nitrophenol completely inhibiting methane fermentation as low as 20 mg/L.     

Biodegradation of multiple cyanobacterial metabolites in drinking water supplies

The fate of multiple cyanobacterial metabolites was assessed in two Australian source waters. The saxitoxins were the only metabolites shown to be non-biodegradable in Myponga Reservoir water, while microcystin-LR (MCLR) and geosmin were biodegradable in this water source. Likewise, cylindrospermopsin (CYN) was shown to be biodegradable in River Murray water. The order of ease of biodegradability followed the trend: MCLR > CYN > geosmin > saxitoxins. Biodegradation of the metabolites was affected by temperature and seasonal variations with more rapid degradation at 24 °C and during autumn compared with 14 °C and during winter. A microcystin-degrading bacterium was isolated and shown to degrade four microcystin variants within 4 h. This bacterium, designated as TT25, was shown to be 99% similar to a Sphingopyxis sp. based on a 16S rRNA gene fragment. Isolate TT25 was shown to contain a homologue of the mlrA gene; the sequence of which was 99% similar to that of a previously reported microcystin-degrader. Furthermore, isolate TT25 could degrade the microcystins in the presence of copper sulphate (0.5 mg L⁻¹ as Cu²⁺) which is advantageous for water authorities dosing such algicides into water bodies to control cyanobacterial blooms.