Incineration of paper sludge in a prototype vortexing fluidized bed combustor

All experiments were carried out in a prototype vortexing fluidized bed combustor (VFBC). The dimension of the combustion chamber is 0.7 x 1.4 x 2 m, and the freeboard section is 1 m i.d. and 4 m in height. Paper sludge was used as the feeding material. Two types of coal particles were employed as the supplementary fuel. In order to understand the characteristics of the VFBC system for paper sludge incineration, the effect of various operating parameters, such as the primary airflow, excess air ratio, and secondary airflow rates, on temperature distribution, ash elutriation, combustion efficiency, and pollutant emissions were investigated.     

Adsorption-desorption characteristics of mercury in paddy soils of China

Mercury (Hg) has received considerable attention because of its association with various human health problems. Adsorption-desorption behavior of Hg at contaminated levels in two paddy soils was investigated. The two representative soils for rice production in China, locally referred to as a yellowish red soil (YRS) and silty loam soil (SLS) and classified as Gleyi-Stagnic Anthrosols in FAO/UNESCO nomenclature, were respectively collected from Jiaxin County and Xiasha District of Hangzhou City, Zhejiang Province. The YRS adsorbed more Hg(2+) than the SLS. The characteristics of Hg adsorption could be described by the simple Langmuir adsorption equation (r2 = 0.999 and 0.999, P < 0.01, respectively, for the SLS and YRS). The maximum adsorption values (Xm) that were obtained from the simple Langmuir model were 111 and 213 mg Hg(2+) kg(-1) soil, respectively, for the SLS and YRS. Adsorption of Hg(2+) decreased soil pH by 0.75 unit for the SLS soil and 0.91 unit for the YRS soil at the highest loading. The distribution coefficient (kd) of Hg in the soil decreased exponentially with increasing Hg(2+) loading. After five successive desorptions with 0.01 mol L(-1) KCl solution (pH 5.4), 0 to 24.4% of the total adsorbed Hg(2+) in the SLS soil was desorbed and the corresponding value of the YRS soil was 0 to 14.4%, indicating that the SLS soil had a lower affinity for Hg(2+) than the YRS soil at the same Hg(2+) loading. Different mechanisms are likely involved in Hg(2+) adsorption-desorption at different levels of Hg(2+) loading and between the two soils.     

经得起时间考验的水资源开发与管理(Ⅰ)

此文是由专家组为联合国环境计划署准备的报告。文章指出,环境意义上的完善与发展,并不是高不可攀的事。我们在工程与某些区域,在综合环境因子的考虑上,已取得较好水平。然而与此同时,我们在国家政策与计划水平上,在设计有效地将环境各因子综合化的手段上,还没有得到最后的成功。     

Electron affinity coefficients of nitrogen oxides and biodegradation kinetics in denitrification of contaminated stream water

During the dry season in Korea, rivers become more vulnerable to contamination by biochemical oxygen demand (BOD) and nitrogen. It is hypothesized that the natural characteristics of the streams in Korea allow the contaminated water to be treated at the tributaries. Down-stream river water quality in Korea may be improved by spraying the contaminated stream water from the tributaries over the surrounding floodplains. The consequent water filtration through the soil could remove the contaminants through aerobic and denitrifying reactions. In this study, the kinetics parameters of the denitrifying reaction in floodplain filtration were determined using contaminated stream water. For the electron donor the Monod kinetics was used, while the competitive Michaelis-Menten model was employed for the electron acceptors. The parameters to the competitive Michaelis-Menten model were found using continuous denitrifying reactions, instead of the batch reactions employed in previous studies, to match the conditions needed to apply the competitive Michaelis-Menten kinetics. From the result, it was found that continuous reactions as well as batch reactions could be used to determine the affinity coefficients in denitrification. The results of this study also showed that the affinity coefficient of NO2, using continuous reactions, was similar to that of other studies in the literature found via batch reactions, whereas the affinity coefficient of N2O was much larger than that acquired with batch reactions. The parameters obtained in this study will be used in future work to simulate the contaminant behaviors during floodplain filtration using a mathematical model.     

Monoclonal antibody-based broad-specificity immunoassay for monitoring organophosphorus pesticides in environmental water samples

The development of easy-to-use and rapid-monitoring immunoassay methods for organic environmental pollutants in a class-selective manner is a topic of considerable environmental interest. In this work, a heterologous competitive indirect enzyme-linked immunosorbent assay (ciELISA) based on a monoclonal antibody (MAb) with broad-specificity for organophosphorus pesticides (OPs) was applied to the detection of O,O-diethyl and O,O-dimethyl OPs in water samples. The ciELISA conditions were carefully optimized to obtain a three to five-fold improvement of sensitivity for most OPs, and thirteen OPs were determined at concentrations ranging from 0.017 to 30 ng mL(-1). The determination of spiked environmental water samples showed average recoveries from 81.5% to 115.1%, with the coefficient of variation (CV) ranging from 6.1% to 20.9%, which showed satisfactory reproducibility of the developed ciELISA. To overcome the negative aspect of broad-specificity immunoassays not providing qualitative and quantitative analysis of individual OPs in blind samples, we used "percent inhibition rate" to make the developed ciELISA a semi-quantitative method, which allows the monitoring of positive samples from hundreds of negative samples. The determination of OPs in blind water samples by the developed ELISA with confirmation by HPLC-MS/MS analysis demonstrated that the assay is ideally suited as a screening method for OP residues prior to chromatographic analysis.     

我国氧化塘废水处理的现状简述

在实地考察和参阅有关文献的基础上，对我国的氧化塘建设和运行情况进行实事求是的描述，并就氧化塘的设计，选择分别进行了详细的分析，供研究和开发这项技术借鉴和参考。     

骆马湖水质保护研究及其对策

江苏省淮河以北是一个水资源缺乏的地区,随着工农业的发展,水污染加剧,使本来紧缺的水资源又受到污染而不能利用。在某种程度上,水污染已经影响人民生活水平的提高和限制了工农业的发展。因此,研究、制定水资源的保护对策具有极为重要的意义。骆马湖起着苏北京杭运河调水及泄洪的蓄水调节作用。进入八十年代,由于上、下游工农业生产的污染,使湖区水质状况越来越差。1984年7月,来自徐州市工业废水的污染,造成骆马湖突发性污染事故,近几年来,山东鲁南也区的工业污染经常给湖区造成污染,死鱼不断发生。这样,不仅影响上下游的工农业生产,也给湖区8000多渔民的生产、生活、带来了困难。因此,对骆马湖水质进行研究,并制定出切实可行的保护对策,是江苏省保护苏北京杭运河水资源、保护南水北调水质急待解决的环境问题之一。     

按照生态规律 发展乡镇经济

宿迁县大新镇地处淮北平原的陆塘河畔,全镇有24个村、43000口人、47000亩耕地。过去,这里是个灾害频繁,农业欠收,十年九荒的穷地方。自党的十一届三中全会以来,这里的干部群众,遵循生态规律,搞好生产,商品经济才得到了迅速发展。几年来,大新镇人从实践中逐步懂得了如何遵循经济规律和生态规律,他们根据本地特点,围绕商品生产这个中心,发展生态经济,形成了“六条龙”生产线。     

Growth responses of in vitro Fusarium oxysporum f. sp. niveum to external supply of tannic acid

Allelochemicals released from root exudates or decaying residues of plants play diversified roles in ecological interactions of plant-pathogen. The objective of this work was to evaluate the allelopathic effect of an externally supplied tannic acid on soil-borne in vitro Fusarium oxysporum f. sp. niveum. Results showed that the tannic acid decreased the growth of the fungus up to 9.5% at 800 mg l(-1). Conidial germination was reduced by 52.3% in comparison with the control. However, sporulation and mycotoxin production by the fungus were stimulated. The activity of pectinase and proteinase were initially increased and finally decreased with increase in concentrations of tannic acid. Tannic acid served as an ecological allelochemical, repressing the growth of the pathogen.