超临界水氧化技术处理含油污水研究

在间歇式实验装置上对超临界水氧化技术处理含油污水进行了研究,主要考察了COD的脱除率与反应时间、温度和压力的关系。实验结果表明,超临界水中的氧化反应能有效去除污水中COD,反应时间、反应温度是影响COD脱除率的重要因素。     

Wet weather impact on trihalomethane formation potential in tributaries to drinking water reservoirs

During rain storm events, land surface runoff and resuspension of bottom sediments cause an increase in Trihalomethane (THM) precursors in rivers. These precursors, when chlorinated at water treatment facilities will lead to the formation of THMs and hence impact drinking water resources. In order to evaluate the wet weather impact on the potential formation of THMs, river samples were collected before, during and after three rain storms ranging from 15.2 to 24.9 mm precipitation. The samples were tested for THM formation potential and other indicators including UV254 absorbance, turbidity and volatile suspended solid (VSS). Average levels of THMs increased from 61 μg/l during dry weather to 131 μg/l during wet weather, and then went back to 81 μg/l after rain ended. Wet weather values of THM are well above the maximum contaminant level (MCL) 80 μg/l, set by EPA for drinking water. THM indicators also exhibited similar trends. Average levels increased from 0.6 to 1.8 abs; 2.6 to 6 ntu; and 7.5 to 15 mg/l respectively for UV254, turbidity and VSS. A positive correlation was observed between THM formation and THM indicators. The t-test of significance (p-value) was less than 0.05 for all indicators, and R values ranged from 0.85 to 0.92 between THMs and the indicators, and 0.72 to 0.9 among indicators themselves.     

Multi-response optimization of Fenton process for applicability assessment in landfill leachate treatment

Fenton process, as a pretreatment method, was found to be effective in the primary treatment of mature/medium landfill leachate. However, the main problem of the process is the large amount of produced sludge that requires an accurate feasibility evaluation for operational applications. In this study, the response surface methodology was applied for the modeling and optimization of Fenton process in three target responses, (1) overall COD removal, (2) sludge to iron ratio (SIR) and (3) organics removal to sludge ratio (ORSR), where the latter two were new self-defined responses for prediction of sludge generation and applicability assessment of the process, respectively. The effective variables included the initial pH, [H₂O₂]/[Fe²⁺] ratio and Fe²⁺ dosage. According to the statistical analysis, all the proposed models were adequate (with adjusted R² of 0.9116–0.9512) and had considerable predictive capability (with prediction R² up to 0.9092 and appropriate adequate precision). It was found that all the variables had significant effects on the responses, specifically by their observed role in dominant oxidation mechanism. The optimum operational conditions obtained by overlay plot, were found to be initial pH of 5.7, [H₂O₂]/[Fe²⁺] ratio of 17.72 and [Fe²⁺] of 195 mM, which led to 69% COD removal, 2.4 (l sludge/consumed mole Fe²⁺) of SIR and 16.5 (gCOD removed/l produced sludge) for ORSR in verification test, in accordance with models-predicted values. Finally, it was observed that [H₂O₂]/[Fe²⁺] ratio and Fe²⁺ dosage had significant influence on COD removal, while Fe²⁺ dosage and [H₂O₂]/[Fe²⁺] ratio had remarkable effects on SIR and ORSR responses, respectively.     

清洁生产——实现我国工业可持续发展的必由之路

从可持续发展战略出发，阐述了目前我国在工业生产发展中面临的问题。为解决工业发展与保护环境的矛盾，实现社会与自然的协调发展，提出了以清洁生产为主，末端处理为辅，从根本上消除污染，节约原料与能源走发展工业的新路。     

Heat as emergency,heat as chronic stress: policy and institutional responses to vulnerability to extreme heat

Increasingly commonplace in cities, extreme heat events introduce multi-stress vulnerability, affecting people’s health and well-being, financial situation, mobility, social relations, and access to basic services. Planning to reduce heat vulnerability has become part of government business and to some extent community-level responses, cutting across a number of sectors including public health, emergency management, social services, critical infrastructure, and housing. This planning is often framed around heat as an emergency, focusing on preventing loss of life and severe health impacts, yet a vulnerability perspective also draws attention to the chronic and persistent impacts of heat. Our research, based on interviews and desktop research in Melbourne, Australia, found tensions between addressing heat as an emergency and heat as a source of chronic stress, with emergency responses taking precedence over responses addressing the chronic dimensions of heat. Each approach results in different but nonetheless related programmatic priorities for reducing vulnerability. In complex institutional settings, improving relations between policy and programme managers, non-government organisations, and vulnerable people themselves would enable the multiple stresses associated with extreme heat to be more effectively addressed. Policy and institutional responses that better appreciate the interconnections between the emergency and chronic aspects of heat would likely reduce vulnerability and contribute to more just approaches to urban sustainability.     

立式加热炉节能减排可行性研究

大庆油田原稳装置采用立式加热炉,烟气中存在大量的废热。在现有装置运行中,烟气直接排放,浪费了大量的热量。通过在实验装置中可回收废热资源及废热回收技术研究,采用热管技术回收烟气废热,用于预热空气,不仅会节能降耗,给企业创造可观的经济效益,还会减少大气污染,创造良好的社会效益。     

Treatment of digestate from a co-digestion biogas plant by means of vacuum evaporation: Tests for process optimization and environmental sustainability

Vacuum evaporation consists in the boiling of a liquid substrate at negative pressure, at a temperature lower than typical boiling temperature at atmospheric conditions. Condensed vapor represents the so called condensate, while the remaining substrate represents the concentrate.This technology is derived from other sectors and is mainly dedicated to the recovery of chemicals from industrial by-products, while it has not been widely implemented yet in the field of agricultural digestate treatment. The present paper relates on experimental tests performed in pilot-scale vacuum evaporation plants (0.100 and 0.025 m³), treating filtered digestate (liquid fraction of digestate filtered by a screw-press separator). Digestate was produced by a 1 MW_e anaerobic digestion plant fed with swine manure, corn silage and other biomasses. Different system and process configurations were tested (single-stage and two-stage, with and without acidification) with the main objectives of assessing the technical feasibility and of optimizing process parameters for an eventual technology transfer to full scale systems.The inputs and outputs of the process were subject to characterization and mass and nutrients balances were determined.The vacuum evaporation process determined a relevant mass reduction of digestate.The single stage configuration determined the production of a concentrate, still in liquid phase, with a total solid (TS) mean concentration of 15.0%, representing, in terms of mass, 20.2% of the input; the remaining 79.8% was represented by condensate. The introduction of the second stage allowed to obtain a solid concentrate, characterized by a content of TS of 59.0% and representing 5.6% of initial mass.Nitrogen balance was influenced by digestate pH: in order to limit the stripping of ammonia and its transfer to condensate it was necessary to reduce the pH. At pH 5, 97.5% of total nitrogen remained in the concentrate. This product was characterized by very high concentrations of total Kjeldhal nitrogen (TKN), 55,000 mg/kg as average.Condensate, instead, represented 94.4% of input mass, containing 2.5% of TKN. This fraction could be discharged into surface water, after purification to meet the criteria imposed by Italian regulation. Most likely, condensate could be used as dilution water for digestion input, for cleaning floor and surfaces of animal housings or for crop irrigation.The research showed the great effectiveness of the vacuum evaporation process, especially in the two stage configuration with acidification. In fact, the concentration of nutrients in a small volume determines easier transportation and reduction of related management costs. In full scale plants energy consumption is estimated to be 5–8 kWh_e/m³ of digestate and 350 kWh_t/m³ of evaporated water.     

电解法处理含镍废水及纯镍的回收

采用电解回收法处理Ni2+含量为2g/L的废水,在阴极回收纯镍。研究了电解电流、极距、NH4Cl浓度、pH值等因素对Ni2+去除率、槽压、阴极能耗的影响,得出最优工艺参数为:温度20℃,电解时间20min时、电解电流300mA,极距15mm,NH4Cl浓度5g/L,pH值8.0,该条件下Ni2+去除率为96.926%,槽压16.21V,阴极能耗22.418kW.h/kg,在阴极可得到沉积6.45μm厚的镍板。     

成都市城市效应对大气环境的影响

本文利用1979—1981年气象资料用统计方法分析了城市热岛效应对主要气象要素时空分布特征的影响(例如:温度、无霜期、风速、日照、云量、降水量、雷暴、雨日、雾日和土壤温度),结果表明:城市效应对市区大气环境的影响是明显的。     

新型电极及其电解阳离子染料染色模拟液研究

本文研制了一种可用于废水处理的新型阳极和阴极，研制电极电解处理离子染料色模拟液时，分解电压低，脱色率高，电能消耗少。