CAST工艺在制革废水处理中的应用

皮革生产企业由于污染严重,污水处理工艺简单、设备落后,最终出水各项指标超标,对环境造成严重污染。CAST工艺处理制革废水,反应条件在缺氧和厌氧之间变化,活性污泥通过酶的作用,不断经历高负荷的基质积累和低负荷的基质降解过程,迅速吸附降解污水中大部分可溶性有机物,抑制丝状菌的生长,有效地防止污泥膨胀,并达到脱氮、除磷的目的。运行结果表明,当进水BOD5为960~1250 mg/l,CODcr为2250~2780mg/l,出水达到《污水综合排放标准》(GB8978-1996)二级标准。     

Impacts of Social and Demographic Factors on Residents’ Subjective Well-being in Rural China

Abstract

The objective of social development is to construct a harmonious society. In China, the key to a harmonious society is the happiness of more than 900 million farmers living in the rural areas. This study aimed to measure rural residents’ subjective well-being (SWB) through the day reconstruction method, as well as to analyze SWB’s influencing factors through a variety of statistical methods. The results showed that the average U index was 12.79%, indicating that respondents were unhappy 12.79% of the time. Twenty-seven percent of the population had a U index greater than 0, with the average value being 47%, indicating that these people were unhappy 47% of the time. The study also found that SWB varied according to the characteristics of the respondents. Logistic regression analysis showed that social and demographic factors, including age, education, county, household size, generation number, per capita income, migration status and social networking, which significantly affected rural residents’ SWB. The size of the impact varied with the different factors.     

Research on the exploitation and utilization degree of mineral water based on ecological base flow in the Changbai Mountain basalt area,northeast China

Environmental Geochemistry and Health - Mineral water from the Changbai Mountain basalt area is China's most important source of drinking water. Mineral water with abundant output and enriched...     

Highly efficient catalytic reduction of 4-nitrophenol and organic dyes by ultrafine palladium nanoparticles anchored on CeO2 nanorods

Environmental Science and Pollution Research - Uniformly dispersed Pd nanoparticles on certain supports exhibit exceptional catalytic performance toward various environmental applications. In this...     

Effects of biowaste-derived biochar on the dynamic behavior of cadmium fractions in soils

Environmental Science and Pollution Research - As a commonly used amendment to soil contaminated by heavy metals, biochar has attracted great attention and has been applied for decades due to the...     

Identifying potentially contaminated areas with MaxEnt model for petrochemical industry in China

Environmental Science and Pollution Research - The presence of heavy metal and organic pollutants in wastewater effluents, flue gases, and even solid wastes from petrochemical industries renders...     

Integrating life cycle assessment and a farmer survey of management practices to study environmental impacts of peach production in Beijing,China

Environmental Science and Pollution Research - While intensive peach production has expanded rapidly in recent years, few studies have explored the environmental impacts associated with specific...     

Simulated adsorption of iodine by an amino-metal-organic framework modified with covalent bonds

Environmental Science and Pollution Research - Radioactive iodine in nuclear waste is increasingly harmful to the human body and the environment because of its strong radioactivity, high fluidity,...     

基于ARIMA模型对扬州市PM2.5的分析和预测

针对扬州市PM2.5浓度变化的时间序列分布特征,应用求和自回归移动平均(ARIMA)模型,分别预测扬州市1月、4月、7月和10月每月的1-5日的PM2.5日均浓度,结果表明,所预测天数中约60％的PM2.5日均浓度与实测值较接近,但仍有极个别天数的PM2.5日均浓度存在较大偏差,说明运用ARIMA模型对扬州市PM2.5...     

促生剂投量对菌剂-促生剂协同修复沉积物的影响

采用5个110 L的模拟河道反应器,在投加菌剂的基础上(底泥稳定后向底泥和水中分别注射浓度为0.09%和0.03%的菌剂),生物促生剂投量分别设计为0(空白对照实验)、0.08、0.09、0.10和0.11 g·L~(-1),通过为期115 d的修复实验研究菌剂与促生剂协同作用时底泥微生物群落特征变化规律,进而分析其对底泥修复效果的影响.实验表明,投加促生剂后,115 d时Chloroflexi、Proteobacteria、Firmicutes、Betaproteobacteria及Bacteroidetes等主要功能菌群相对丰度增加,脲酶活性与蛋白酶活性后期时总体上低于单独投加菌剂组.促生剂投量为0.10 g·L~(-1)时,上覆水COD_(Cr)稳定浓度为16.82 mg·L~(-1),低于其余各组;底泥TOC含量由初始的0.808%下降至第115 d时的0.687%,去除率为14.9%,显著高于其余各组;促生剂投量为0.11 g·L~(-1)时,底泥全氮去除率最高为14.8%.生物促生剂促使微生物群落向更适宜降解去除氮素及有机质的方向演替,有效改善底泥环境.