用钢渣处理含砷废水

对用钢渣处理含硫废水进行了试验，用配水探讨了钢渣投加量，水样，ＰＨ，混合时间等因素对除砷效果的影响，结果表明，钢渣具有较好的除砷效果。     

Statistical analysis as a tool for discriminating dioxin formation pathways

Typical thermal fingerprints are rather evenly composed of all available polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) congeners, a feature also linked with CuCl₂-catalysis. Conversely, chlorophenol condensation patterns are supported strongly by CrCl₃-, ZnCl₂- and CdCl₂-catalysis; they feature selective formation of, e.g., 1,3,6,8- and 1,3,7,9-TCDD arising from mainly 2,4,6-trichlorophenol, a chlorophenol well-represented in incinerator flue gas. Just few, well-defined PCDD-congeners steadily emerge from chlorophenols. Surprisingly, it is experimentally established that these are not generally formed by parallel processes. Additionally, the formation of four important 2,3,7,8-substituted TCDD/F- and PeCDD/F-congeners is statistically quasi-unrelated. Apparently, external (α) or lateral (β)-chlorination occurs as a chance event, contrary to observations and hypotheses in earlier studies. These statements are corroborated by selected congener-to-congener representations. For performing this statistical analysis, simple techniques are followed. Cross-correlation matrices show a relationship for each pair of PCDD/F-congeners in a particular data set: PCDD/F-congener pairs statistically correlate, anti-correlate, or appear rather neutral. In this paper, these novel concepts were applied on data, established during tests on Model Fly Ash (MFA); principal component analysis was used to demonstrate the relevance of MFA-data in relation to municipal solid waste incineration signatures.     

Modeling Water Quantity and Sulfate Concentrations in the Devils Lake Watershed Using Coupled SWAT and CE‐QUAL‐W2

Devils Lake is an endorheic lake in the Red River of the North basin in northeastern North Dakota. During the last two decades, the lake water level has risen by nearly 10 m, causing floods that have cost more than 1 billion USD in mitigation measures. Another increase of approximately 1.5 m in the lake water level would cause spillage into the Sheyenne River. To alleviate this potentially catastrophic spillage, two artificial outlets were constructed. However, the artificial drainage of water into the Sheyenne River raises water quality concerns because the Devils Lake water contains significantly higher concentrations of dissolved solids, particularly sulfate. In this study, the Soil and Water Assessment Tool (SWAT) was coupled with the CE‐QUAL‐W2 model to simulate both water balance and sulfate concentrations in the lake. The SWAT model performed well in simulating daily flow in tributaries with E_NS > 0.5 and |PBIAS| < 25%, and reproduced the lake water level with a root mean square error of 0.35 m for the study period from 1995 to 2014. The water temperature and sulfate concentrations simulated by CE‐QUAL‐W2 for the lake are in general agreement with the field observations. The model results show that the operation of the two outlets since August 2005 has lowered the lake level by 0.70 m. Furthermore, the models show pumping water from the two outlets raises sulfate concentrations in the Sheyenne River from ~100 to >500 mg/L. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.     

Decreasing the knowledge gap among different socioeconomic status groups on the issue of climate change

Climate change is causing severe negative consequences to small low-lying islands. To mitigate and adapt to climate change, it is important to improve public knowledge on its causes and consequences. As a social issue that needs collective action to address, the knowledge gap among different segments of population would be a barrier to people’s behaviors toward mitigation and adaption to climate change. This study aims to investigate public knowledge acquisition of climate change by revisiting the knowledge gap hypothesis. A nationally representative random computer-assisted telephone interview survey (N?=?1093) was conducted in Singapore. Quantitative analyses revealed that both newspaper reading and television viewing could reduce the knowledge gap between high and low socioeconomic status individuals. We recommend that governments and relevant authorities should utilize mass media to disseminate information and cultivate public understanding of climate change.     

混凝沉淀-活性炭生物池工艺处理聚苯乙烯废水

可发性聚苯乙烯废水中含有大量表面活性剂(LAS)和其他一些难降解的苯环类物质,总磷高,可生化性差,较难处理,采用中和混凝沉淀-活性炭生物池工艺处理可发性聚苯乙烯(EPS)废水,当进水平均COD_(Cr)为1800mg/L时,出水在80mg/L左右,去除率达95.5%,出水水质稳定,各项水质指标均达到了国家一级排放标准。     

皂素生产废水的资源化综合利用实验

皂素生产废水是强酸性高浓度有机废水,富含淀粉水解后的糖类.据此特点,以皂素生产中的一次废水为原料,经中和处理后进行酒精发酵,使废水资源化.结果表明,采用工业氨水为中和剂,中和用量为5.20%(体积分数),发酵接种量为10%(体积分数),总发酵时间为60 h时,4 L废水可生产出95%的工业酒精120 mL.一次废水COD去除率达75%,后续废水量大大减少,具有明显的环境效益.经估算每生产lt工业酒精可处理4lt一次废水,与生产成本相比,具有明显的经济效益.     

泛比电阻电除尘器收尘性能实验研究

泛比电阻电除尘器是一种具有辅助电极和交错平板收尘电极的新型电除尘器.通过对其伏安特性及除尘效率的试验研究,并与传统线板式静电除尘器进行比较,结果表明辅助电极对电晕电流具有明显的抑制作用,在相同的外加电压下,泛比电阻电除尘器对高比电阻锅炉飞灰的收尘效率比普通的线板式电除尘器明显要高.     

Laser-induced breakdown spectroscopy application in environmental monitoring of water quality: a review

Water quality monitoring is a critical part of environmental management and protection, and to be able to qualitatively and quantitatively determine contamination and impurity levels in water is especially important. Compared to the currently available water quality monitoring methods and techniques, laser-induced breakdown spectroscopy (LIBS) has several advantages, including no need for sample pre-preparation, fast and easy operation, and chemical free during the process. Therefore, it is of great importance to understand the fundamentals of aqueous LIBS analysis and effectively apply this technique to environmental monitoring. This article reviews the research conducted on LIBS analysis for liquid samples, and the article content includes LIBS theory, history and applications, quantitative analysis of metallic species in liquids, LIBS signal enhancement methods and data processing, characteristics of plasma generated by laser in water, and the factors affecting accuracy of analysis results. Although there have been many research works focusing on aqueous LIBS analysis, detection limit and stability of this technique still need to be improved to satisfy the requirements of environmental monitoring standard. In addition, determination of nonmetallic species in liquid by LIBS is equally important and needs immediate attention from the community. This comprehensive review will assist the readers to better understand the aqueous LIBS technique and help to identify current research needs for environmental monitoring of water quality.     

Assessing the visual quality of green landscaping in rural residential areas: the case of Changzhou, China

Changzhou is a typical waterside municipality with approximately 2,500 years of history located south of the Yangtze River. It was an agriculturally oriented region but is becoming an industrialized region. Rural green landscaping in this region possesses characteristics of traditional Chinese gardens. This paper presents a methodology for assessing the visual quality of green landscaping in rural residential areas through public perception-based and expert/design approaches. The former approach enables us to rank green landscaping based on a survey of public preference; the latter weighs the contributions of the attributes contained in a photograph to its overall scenic beauty via correlation, regression, and factor analyses. The photographs used in the survey included road greenways, riparian greenways, residential public gardens and green landscaping around houses, with each type of landscape represented by seven photographs. In total, 141 college students and 41 other participants ranked photographs of each landscaping type from highest to lowest preference. The results indicate that the preferences of students are similar to those of the general public. Examples of green landscaping depicted in the “best” four photographs possessed more attractive qualities regarding the variety of vegetation, richness of colors and a selection of human additions compared to those depicted in the “worst” photographs. The perceived visual quality was positively influenced by, in decreasing order of importance, the variety of vegetation, color contrast, the openness of green spaces, the area of vegetation, and positive man-made elements; conversely, it was negatively influenced by the type of topography. Moreover, some suggestions were offered for future rural greening regarding perceived visual beauty.     

炼油废碱液的综合利用

炼油废碱液是石油加工过程中采用氢氧化钠溶液吸收硫化氢、碱洗油品产生的含硫废碱液和含环烷酸钠废碱液。通过研究 ,综述了炼油废碱液的利用技术主要有熬制工业硫化碱、结晶提取Na2S、废碱液造纸制浆、沉淀法再生废碱液和中和法回收环烷酸等。试验发现 ,Fe2O3、ZnO等沉淀剂对有机硫几乎无脱除效果 ,处理后碱液仍散发出恶臭味。经过大量试验和选择 ,采用CuO作沉淀剂 ,不仅沉淀了S2 - ,而且RS -也得以氧化 ,并发现滤渣对残余有机硫有强烈的吸附作用 ,得到了无色、无臭的再生碱液。