城镇污水处理厂污泥处置与资源化利用

由于城市污水处理厂不断建成与使用,污泥量的增加速度越来越快,大量未稳定处理的污泥已成为沉重的负担,如果污泥不及时处埋,将会引起严重的二次污染。通过对当前污泥处理与处置技术发展现状、经济属性的分析,结合实例,探讨了我国城市污水处理厂污泥的处理和处置的主要途径并分析其优缺点,从而使我国城市污水处理厂污泥达到无害化处理、资源化利用与产业化发展的目的。     

净水厂沉淀池排泥水回用及其生物稳定性

基于净水厂沉淀池排泥水回用的中试试验,探析排泥水回用工艺出水水质安全和生物稳定特性,探讨净水厂排泥水回用的可行性。试验表明:排泥水的AOC和BDOC浓度均值分别为98. 16μg/L和1. 92mg/L,且AOC和BDOC浓度与水温呈显著线性相关特性;污泥回流比(泥水∶原水)为3%时,出水未检出细菌总数,且出水浑浊度、氨氮、CODMn等指标均满足《生活饮用水卫生标准》(GB5749-2006);出水的AOC和BDOC浓度均值分别为88. 67μg/L和0. 21 mg/L,保障了水质的生物稳定性。因此,净水厂在合理控制回流比条件下,排泥水回用不仅具有可实施性,而且实现了净水厂节能减排的可持续发展理念。     

H2O2、Fenton试剂与活性炭联用对CODCr去除效果的对比试验研究

为了开发高效低成本、达到回用水质标准的污水处理工艺,本试验采用H2O2、Fenton试剂与活性炭联用对CODCr进行去除的对比试验研究。结果表明：在室温下200 mL水样,当pH为3,震荡强度为150 rpm时,Fenton试剂-活性炭联用与H2O2-活性炭相比,活性炭用量少200 mg,时间缩短10 h,CODCr去除率高17.6%。试验揭示了Fenton试剂-活性炭联用的反应机理：Fe2＋与活性炭共同催化分解H2O2生成大量.OH,能快速氧化降解有机物,使CODCr浓度迅速降低。从工程应用角度和技术经济方面考虑,Fenton试剂-活性炭联用的pH值在5～7适宜;且处理成本更低。Fenton试剂-活性炭联用是处理二级出水CODCr高效、低耗的方法,值得进一步研究和推广应用。     

Use of Stable Isotopes to Trace Municipal Wastewater Effluents into Food Webs within a Highly Developed River System

Many anthropogenic inputs, such as municipal wastewater effluents (MWWEs), affect stable isotope signatures (δ¹³C and δ¹⁵N) at the base of exposed food webs creating spatial patterns reflecting their incorporation into aquatic food webs. The Grand River in southern Ontario, Canada, is a heavily modified, rapidly urbanizing river that assimilates wastewater from 30 municipal wastewater treatment plants. Stable isotope analysis was applied to resident aquatic invertebrates and fish influenced by three different wastewater outfalls in early, middle, and late summer to determine how values shifted seasonally and with differing effluent quality. There was a slight increase in δ¹³C in both invertebrates and fish in late summer downstream from the three outfalls, but it is difficult to separate effects of the effluents from downstream gradients. Downstream of two of the three outfalls, the δ¹⁵N tended to increase relative to upstream, while the remaining effluent, of the poorest quality, decreased δ¹⁵N values of both invertebrates and fish. Spatial trends in stable isotopes became more pronounced as the summer progressed with the greatest between‐site differences occurring in late summer. This study reflects the complex nutrient dynamics associated with MWWE inputs to rivers and contributes to our understanding and application of stable isotope analysis in impacted lotic ecosystems. Copyright © 2014 John Wiley & Sons, Ltd.     

The Impact of Sustainability Aspects in the Meat Sector: A Cluster Analysis Based on Consumer Attitudes and Store Format Choice

Several consumer studies have shown considerable market potential for sustainable meat products, however, their markets shares are still marginal. In Germany, the sustainable aspects “organic,” “local origin,” and “animal welfare” are of special interest. To obtain a precise overview of potential target groups for these meat categories and their choice of store format, 620 German consumers were surveyed on their attitudes toward sustainable meat production and their shopping behavior. First, target groups based on consumers’ attitudes were identified by cluster analysis, taking into account possible overlaps. Consumers were also clustered by their store format choice and their preferred type of meat packaging. A cross tabulation of the results then provided insights into which store format and type of meat packaging is preferred by the target groups for sustainable meat products. Due to overlaps found in the target groups, the existence of important subgroups was shown. Amongst the target groups, only a slight preference for unpackaged meat products was found. Basically, the offer of sustainable meat products appears of interest for all store formats, with particular emphasis on supermarkets. The results of this study can support producers and retailers developing new and tailored marketing strategies for sustainable meat products.     

Effect of Consumption Values on Women’s Choice Behavior Toward Organic Foods: The Case of Organic Yogurt in Iran

The purpose of this study is to examine the effects of consumption values (i.e., functional value, social value, emotional value, conditional value, epistemic value, environmental value, and health value) on women’s choice behavior toward organic yogurt. Structural equation modeling is used to assess data collected by a questionnaire survey. The results indicate that functional value–quality, functional value–taste, and functional value–price; conditional value; epistemic value; and health value have positive effects on choosing organic yogurt by women, and social value, emotional value, and environmental value have no effects on the subject. Among variables, epistemic value and health value have the highest impact on consumer choice behavior toward organic yogurt. So this study concludes that the main influence factors on choice behavior regarding organic yogurt are epistemic value and health value. In fact, consumers have high knowledge about organic yogurt benefits related to their health.     

卤水用于印染废水脱色处理的研究

将卤水作为一种成本较低的水处理药剂用于印染废水脱色处理。考察pH、卤水投加量、沉降时间等对单一组分有色废水脱色效果的影响,并对实际废水进行了脱色处理试验。结果表明,卤水对试验单一有色废水具有良好的脱色效果,在Mg2+浓度为150mg/L,pH为10.5~11时,脱色率可以达到92.4%;实际废水的脱色率平均为90.6%,CODCr去除率平均为58.6%。     

一体式厌氧平板膜生物反应器处理酒厂废水的研究

研究了容积负荷、水力停留时间对一体式厌氧平板膜生物反应器处理高浓度酒厂废水效果的影响。试验结果表明,CODCr负荷为5．2～8 kg／(m3·d),水力停留时间3～5 d时,CODCr平均去除率为95％。正常运行时的碱度与VFA的比为2．5～4．5。当CODCr负荷超过10 kg／(m3·d),系统 VFA出现累积,COD去除率下降。水力停留时间对一体式厌氧平板膜生物反应器处理效果有重要影响,水力停留时间应大于70 h。     

纳滤膜对饮用水中可同化有机碳的去除效果

考察了纳滤膜对饮用水中有机物和可同化有机碳(AOC)的去除效果。对纳滤膜进水和出水进行了AOC的相对分子质量分布测定,分析AOC和有机物相对分子质量分布间的关系,探讨纳滤膜去除AOC的机理。结果表明,纳滤膜能有效地去除TOC和UV254,去除率均高达95%以上;在不同季节,自来水中AOC浓度有显著的变化,其中AOCP17约占AOC总量的60%~70%;纳滤膜对饮用水中AOC的去除率约为60%,其去除效果受到筛分效应和电荷效应的双重影响。AOC多与相对分子质量小于1000的有机物有关。     

生物助剂在制浆废水处理中的应用研究

对某制浆厂生产废水处理系统投加由多种酵素混合而成的生物助剂前后的运行效果进行详细分析.结果表明:在工艺运行参数不变的条件下,使用生物助剂能够提高生物处理系统的生物活性,增加活性生物量,使生物处理系统对CODCr、SS、色度去除率分别提高16%、17%、27%,降低了化学处理单元药剂使用量,增强了生物处理系统的耐冲击负荷能力,降低了水处理成本,对生物助剂在制浆废水处理中应用具有重要的推动作用.