有机磷酸酯阻燃剂降解方法的研究进展

有机磷阻燃剂(OPFRs)已取代溴代阻燃剂广泛应用于各行业,并很容易通过挥发、磨损等方式进入各环境介质中.目前,已在水体、土壤等环境介质中检测到了 OPFRs的存在.本文总结了目前已有的OPFRs在环境中的降解方式,据其原理主要可分为化学法和生物法,化学法主要包含Fenton/类Fenton氧化法、紫外-双氧水法(UV...     

Influence of Prey and Nutritional Status on the Rate of Nitrogen Uptake by Prymnesium parvum (haptophyte)1

Lindehoff, Elin, Edna Granéli, and Patricia M. Glibert, 2010. Influence of Prey and Nutritional Status on the Rate of Nitrogen Uptake by Prymnesium parvum (Haptophyte). Journal of the American Water Resources Association (JAWRA) 46(1):121-132. DOI: 10.1111/j.1752-1688.2009.00396.x Abstract: We studied how the specific nitrogen (N) uptake rates of nitrate (NO₃⁻), urea, and the amino acids, glutamic acid and glycine, by Prymnesium parvum were affected by (1) the change from N-deficient status to N-sufficient status of the P. parvum cells, (2) presence of prey from a natural Baltic Sea plankton community, and (3) the composition of prey as affected by additions of terrestrial originated dissolved organic matter (DOM) or inorganic nutrients. Nitrogen-deficient P. parvum (16 μM NO₃⁻ and 4 μM PO₄⁻, molar N:P ratio of 4:1) were mixed with a natural Baltic plankton community and given PO₄³⁻ and (1) NO₃⁻ (control) or (2) high molecular weight DOM, >1 kDa concentrated from sewage effluent (+DOM), in a molar N:P ratio of 9-10:1. With additions of ¹⁵N-enriched substrates, rates of N uptake from NO₃⁻, urea, and the amino acids glycine and glutamic acid were measured every 24 h for 72 h. Initial N-deficient P. parvum were highly toxic (3.7 ± 0.9 × 10⁻⁴ mg Sap equiv/cell) and toxic allelochemicals were released into the medium causing the natural plankton community to lyse. Rates of N uptake differed between the “control” and the “+DOM” treatments over time; total (sum of the N substrates measured) absolute uptake rates (ρ_cell, fmol N/cell/h) at ambient culture conditions were significantly higher (ANOVA, p < 0.05) in the more toxic “control” treatments compared with the “+DOM” treatments after 48 h. In the “control” treatment, the total ρ_cell increased significantly (ANOVA, p < 0.01) from time 0 to 48 h, while in the “+DOM” treatment there was no significant increase. Released organic nutrients from the lysed plankton cells may have increased uptake rates of amino acids and urea by P. parvum. All uptake rates declined in all treatments by 72 h. Total dissolved N uptake rates at ambient culture conditions were estimated to make up about 10% of the N P. parvum are potentially capable of ingesting from particulate prey.     

城镇化地区水文过程实验观测与模拟——以太湖西苕溪流域安吉实验小区为例

城镇化的发展使不透水面积不断增加,往往导致地区的水文过程发生较为明显的改变。以太湖上游西苕溪流域内的安吉城镇化实验小区为例,在对研究流域50多a长系列水文气象资料和区域城镇化特征作较详细分析的基础上,结合2005~2008年短时间尺度降雨径流观测实验,通过雨量、水位以及下垫面等数据分析,选用Storm Water Management Model这一暴雨洪水管理模型对该地区的典型洪水过程进行了模拟,对其降雨径流规律进行了分析。结果表明：该模型对该区域的模拟效果较好,误差较小,可以用于该城镇化地区的降雨径流过程模拟和洪水规律定量分析;分析该实验小区降雨径流过程可知,城镇化使该地区洪水上涨过程明显加快,6场典型洪水的峰型系数均值为305,洪峰流量增大而滞时缩短,较快的汇流速度使该地区的防洪压力较大。实验观测方法及模拟分析成果将有助于对太湖地区小流域城镇洪水过程特征与规律的认识,对我国东部城镇地区的防洪、规划与管理也具有重要的借鉴意义     

Influences of sediment dessication on phosphorus transformations in an intertidal marsh: formation and release of phosphine

This study investigated the effects of sediment dewatering on the phosphorus transformations concerning about the production and emission of phosphine in the intertidal marsh of the Yangtze Estuary. The concentrations of matrix-bound phosphine ranged from 18.62-72.53 ng kg⁻¹ and 31.14-61.22 ng kg⁻¹ within the August and January exposure incubations, respectively. The responses of matrix-bound phosphine concentrations to sediment dessication demonstrate that the production (or accumulation) of matrix-bound phosphine significantly increased with water loss at the start of the emersion incubations. However, further dehydration inhibited the formation of matrix-bound phosphine in sediments. The significant correlations of matrix-bound phosphine with the organic-P bacteria abundance and alkaline phosphatase activities implicate that the production of matrix-bound phosphine within the dessication incubations was linked closely to the microbial decomposition of organic P. The emissions of phosphine generally decreased with sediment dewatering, with the fluxes of 7.51-96.73 ng m⁻² h⁻¹ and 5.34-77.74 ng m⁻² h⁻¹ over the exposure incubations of both August and January, respectively. Also, it is observed that the releases of phosphine during the entire exposure periods were affected not only by its production but also by sediment water and redox conditions.     

农村小型生活污水处理技术研究进展

针对农村的实际情况,寻找高效低耗的农村生活污水处理技术是很有实际意义的。本文主要从活性污泥法、生物膜法、人工湿地和组合工艺这几方面介绍了农村小型生活污水的处理现状,介绍了近几年来国内外的一些农村小型生活污水处理的研究发展情况。采用生物生态组合工艺,操作管理简单,投资和运行费用较低,适宜在农村小型生活污水处理中应用。     

LCA of local strategies for energy recovery from waste in England, applied to a large municipal flow

An intense waste management (WM) planning activity is currently undergoing in England to build the infrastructure necessary to treat residual wastes, increase recycling levels and the recovery of energy from waste. From the analyses of local WM strategic and planning documents we have identified the emerging of three different energy recovery strategies: established combustion of residual waste; pre-treatment of residual waste and energy recovery from Solid Recovered Fuel in a dedicated plant, usually assumed to be a gasifier; pre-treatment of residual waste and reliance on the market to accept the ‘fuel from waste’ so produced. Each energy recovery strategy will result in a different solution in terms of the technology selected; moreover, on the basis of the favoured solution, the total number, scale and location of thermal treatment plants built in England will dramatically change. To support the evaluation and comparison of these three WM strategy in terms of global environmental impacts, energy recovery possibilities and performance with respect to changing ‘fuel from waste’ market conditions, the LCA comparison of eight alternative WM scenarios for a real case study dealing with a large flow of municipal wastes was performed with the modelling tool WRATE. The large flow of waste modelled allowed to formulate and assess realistic alternative WM scenarios and to design infrastructural systems which are likely to correspond to those submitted for approval to the local authorities. The results show that all alternative scenarios contribute to saving abiotic resources and reducing global warming potential. Particularly relevant to the current English debate, the performance of a scenario was shown to depend not from the thermal treatment technology but from a combination of parameters, among which most relevant are the efficiency of energy recovery processes (both electricity and heat) and the calorific value of residual waste and pre-treated material. The contribution and relative importance of recycling and treatment/recovery processes change with the impact category. The lack of reprocessing plants in the area of the case study has shown the relevance of transport distances for recyclate material in reducing the efficiency of a WM system. Highly relevant to the current English WM infrastructural debate, these results for the first time highlight the risk of a significant reduction in the energy that could be recovered by local WM strategies relying only on the market to dispose of the ‘fuel from waste’ in a non dedicated plant in the case that the SRF had to be sent to landfill for lack of treatment capacity.     

Degradation of atrazine using solar driven fenton-like advanced oxidation processes

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) was degraded using cobalt-peroximonosulfate (Co/PMS) advanced oxidation process (AOP). Three Co concentrations (0.00, 0.25 and 0.50 mM) and five peroximonosulfate (PMS) concentrations (0, 5, 8, 16 and 32 mM) were tested. Maximum degradation reached was 88% using dark Co/PMS in 126 minutes when 0.25 mM of cobalt and 32 mM of PMS were used. Complete atrazine degradation was achieved when the samples were irradiated by the sun under the same experimental conditions described. Tests for identification of intermediate products allowed identification and quantification of deethylatrazine in both dark and radiated conditions. Kinetic data for both processes was calculated fitting a pseudo-first order reaction rate approach to the experimental data. Having kinetic parameters enabled comparison between both conditions. It was found that the kinetic approach describes data behavior appropriately (R² ≥ 0.95). Pseudo-kinetic constants determined for both Co/PMS processes, show k value of 10^?4 for Co/PMS and a k value of 10^?3 for Co/PMS/ultraviolet (UV). This means, that, with the same Co/PMS concentrations, UV light increases the reaction rate by around one order of magnitude than performing the reaction under dark conditions.     

Degradation of ethylenethiourea pesticide metabolite from water by photocatalytic processes

In this study, photocatalytic (photo-Fenton and H₂O₂/UV) and dark Fenton processes were used to remove ethylenethiourea (ETU) from water. The experiments were conducted in a photo-reactor with an 80 W mercury vapor lamp. The mineralization of ETU was determined by total organic carbon analysis, and ETU degradation was qualitatively monitored by the reduction of UV absorbance at 232 nm. A higher mineralization efficiency was obtained by using the photo-peroxidation process (UV/H₂O₂). Approximately 77% of ETU was mineralized within 120 min of the reaction using [H₂O₂]₀ = 400 mg L^?1. The photo-Fenton process mineralized 70% of the ETU with [H₂O₂]₀ = 800 mg L^?1 and [Fe²⁺] = 400 mg L^?1, and there is evidence that hydrogen peroxide was the limiting reagent in the reaction because it was rapidly consumed. Moreover, increasing the concentration of H₂O₂ from 800 mg L^?1 to 1200 mg L^?1 did not enhance the degradation of ETU. Kinetics studies revealed that the pseudo-second-order model best fit the experimental conditions. The k values for the UV/H₂O₂ and photo-Fenton processes were determined to be 6.2 × 10^?4 mg L^?1 min^?1 and 7.7 × 10^?4 mg L^?1 min^?1, respectively. The mineralization of ETU in the absence of hydrogen peroxide has led to the conclusion that ETU transformation products are susceptible to photolysis by UV light. These are promising results for further research. The processes that were investigated can be used to remove pesticide metabolites from drinking water sources and wastewater in developing countries.     

旋转填充床中Fenton＋O3氧化降解模拟阿莫西林废水

以旋转填充床（RPB）作为反应装置,研究了Fenton工艺与Fenton＋O3工艺处理模拟阿莫西林废水的效果,考察了FeSO4·7H2O的投加量、温度、旋转床转速、液体流量及pH对C0D去除率的影响。实验表明,Fenton＋O3工艺的COD脱除率及BOD5／COD相对于Fenton工艺分别提升26．7％和140％。该工艺在pH为3、温度为25℃、液体流量30L／h、气体流量2．5L／h、转速800r／min、H2O2的投加量为1mmol／L及Fe2＋投加量为0．4mm01／L的条件下,100mg／L的模拟阿莫西林废水中COD的去除率达到57．9％,BOD5/COD从0增加到0．36,满足后续生化处理要求。     

重金属Cr(Ⅵ)和Ni对旱伞草富集能力及其生理生化指标的影响

采用水培方法,研究了在不同重金属Cr(Ⅵ)(0~50 mg/L)和Ni(0~50 mg/L)浓度下旱伞草(Cyperus alternifolius)的富集能力及生理生化指标的变化规律。研究结果表明:(1)旱伞草中积累的重金属含量随处理浓度的增加逐渐增加,Cr(Ⅵ)在其地上部和根部富集量分别达到958.00 mg/kg和2 874.44 mg/kg,Ni在其地上部和根部富集量分别达到1 655.46 mg/kg和2 511.20 mg/kg;(2)在Cr(Ⅵ)和Ni胁迫下,随着Cr(Ⅵ)和Ni浓度的增加,旱伞草生物量、叶绿素含量、根系活力均呈先上升后下降的趋势;(3)脯氨酸的含量随着Cr(Ⅵ)胁迫浓度的增加,呈现为先上升后降低的趋势,而随着Ni胁迫浓度的增加,则为先缓慢上升而后急剧升高。旱伞草对Cr(Ⅵ)和Ni具有较强的富集能力且主要分布在根部,虽不是Cr(Ⅵ)和Ni超积累植物,但具有较强的稳定化能力,在污染水体的修复方面有一定应用潜力。