酸化赤泥吸附环丙沙星的特征、机理及过程优化

为提高赤泥的资源化利用及抗生素有机废水的深度处理,以酸化赤泥为吸附剂、环丙沙星为目标污染物,研究了酸化赤泥吸附环丙沙星的条件、特征和机理.采用响应面法中Box-Behnken设计方法,以吸附温度、溶液pH值、环丙沙星初始浓度、酸化赤泥投加量为自变量,吸附量为响应值建立4因素3水平优化模型,确定了最佳吸附条件,并对吸附过程的动力学模型、等温线模型、热力学特性及吸附机理进行了研究.结果表明,溶液pH值、环丙沙星初始浓度、酸化赤泥投加量为影响吸附量的显著因素.酸化赤泥吸附环丙沙星的最佳条件为：温度45℃、pH=3.04、环丙沙星初始浓度29.20mg/L,酸化赤泥投加量3.40g/L,预测最大吸附量为7.30mg/g.酸化赤泥吸附环丙沙星的过程遵循伪二级反应动力学模型及Langmuir-Freundilich吸附等温线模型,经过拟合最大吸附量分别为7.90和7.35mg/g.根据Van Tehoff公式计算吸附热力学状态函数ΔG⁰为-82.13~-94.37kJ/mol、ΔS⁰为0.61J/（mol·K）、ΔH⁰为100.25KJ/mol,吸附为自发进行的吸热反应.FTIR表明环丙沙星分子中-COO与酸化赤泥的Al-O键发生络合反应,C=O与Fe-O键发生微弱的静电或内球面键合作用.研究表明,酸化赤泥是一种极具潜力的廉价吸附剂,可用于处理抗生素污染废水.     

基于蒙特卡洛法的曲轴结构优化分析

目的:为减轻曲轴质量,对16缸V型柴油机的曲轴进行结构优化。方法:首先,按照柴油机真实的工作环境对曲轴单个曲柄的有限元模型进行边界条件和力的加载,求解获得最大应力及最大位移的数值及位置;然后,建立垂直曲柄中心截面的2D有限元模型,在等效加载的情况下应用ANSYS计算最大应力及位移,计算结果同三维模型进行比较,证明2D截面网格的计算合理性;最后,运用ANSYS PDS模块,基于蒙特卡洛抽样方法,对单位曲柄进行主要尺寸优化。结果:主轴颈直径150 mm、曲柄销直径125 mm、圆角半径4.5 mm时单曲柄质量降低3.37 kg,整个曲轴质量降低26.99 kg,到达优化的目的。结论:证明了二维模型替代三维模型的合理性以及运用蒙特卡洛法进行结构优化的可行性,为今后的曲轴优化提供了参考。     

CFB锅炉环保项目SNCR工艺优化提效研究

某炼化企业自备电厂循环流化床锅炉(简称CFB锅炉)环保项目所采用的脱硝方法为选择性非催化还原脱硝(简称SNCR),使用的还原剂为尿素,SNCR系统投用后,虽然能使NOX排放量显著下降,但尿素用量明显过度,增加了企业脱硝成本,并导致脱硫废水氨氮含量超标。为了应对这一情况,本研究主要通过现场调节锅炉运行参数,以及基于CFD建模的方法研究出高效可靠的SNCR工艺优化调整策略及方法,结果表明:在锅炉燃料煤∶焦=4∶1掺烧比例下,氧含量不宜超过3%,有利于降低NOX生成量;控制减少石灰石量有助于提升NOX的脱除效率;通过模拟计算发现下半部喷枪起到主要的脱硝作用,可适当减少上半部喷枪、提升环下半部喷枪的尿素喷入量来提高脱硝效率。为煤焦混烧CFB锅炉脱硝系统的优化提供指导和借鉴作用。     

人居环境的可控性

针对人居环境的复杂性、动态性以及纷繁复杂的影响因素，试图以系统论的观点考查人居环境的可能性发展空间，提出了人居环境大系统的观点，阐述了人工系统、人文系统和自然系统的构成和关系，提出并论述了通过结构优化、功能模拟、反馈控制等方法促使人居环境系统得到合理发展的观点。     

三普2#地热站供热工程设计方案优化分析

通过分析地热供热的相关概念，建立了高效利用地热能源的一系列实现途径。根据工程的基础材料，从技术和经济方面对单纯地热供热方案、地热燃气调峰方案、热泵配置方案以及最终的组合方案进行了优化和调整，从而为三普2#地热井供热工程提供了优化方案，提高了该地区的地热利用率。     

地方政府推进循环经济发展的局限性及对策研究——以山东省日照市为例

在分析日照市发展循环经济的路径、措施和难题的基础上，研究了地方政府的自利性、选择性偏差、调控手段和行政分割等方面的局限性，提出了规范中央政府和地方政府关系、构建科学的政绩考核体系、加强区域分类指导、加快立法与强化执法、制定相应的经济制度与政策等发展循环经济的建议。     

CONJUNCTIVE SURFACE AND GROUND WATER MANAGEMENT IN THE JAKARTA REGION,INDONESIA1

ABSTRACT: This study investigates the degree of economic inefficiency of the current institutional arrangements for surface and ground water management in meeting urban water demand in the Jakarta region. A numerical model of integrated surface and ground water management is developed using GAMS (General Algebraic Modelling System) software. The model maximizes the net present value of social benefits from piped water and ground water consumption across all users over time from 1999 to 2025. Four policy scenarios are examined: the status quo, the social planner's solution, and two ground water pumping quota scenarios: an aggregate ground water pumping quota and a partial quota applied to commercial and industrial users. Three variations in each policy scenario are considered: investment in water infrastructure of the Jakarta water enterprise (PAM Jaya), water demand growth, and discount rates. The status quo, depending on the investment option, the growth of water demand, and the discount rate, results in a 7.4 to 47.8 percent loss in economic efficiency relative to the social planner's solution. The partial quota is the most feasible, applicable, and manageable scenario. The optimal investment option could increase the volume of piped water supply and reduce the cost of water production. The volume of water delivery could increase by up to 156 percent, but it implies only a 35 percent increase in the surface raw water demands above the current level. However, it does not significantly reduce cumulative ground water extraction over the time period considered.     

丹江口水库水质要素变化特征及其相互关系

采用丹江口水库 1987～ 1996年间的水环境常规监测资料 ,应用因子分析方法探讨了丹江口水库不同区域水环境要素变化特征及其相互关系 ,分析表明 :丹江口水库目前水质良好 ,大多数情况下能满足地面水一类水质标准要求 :库区不同断面水体水质要素及污染因子间的相互关系可以用 6个主导因子表达。同一主导因子不同断面标识因子的差异反映了库区不同区域水质分布差异及产生这种差异的环境过程 ;影响库区水质的主要因素是上游随降水产生的面源污染、库周点源排放、水体自净以及气候因素 ,不同断面水质影响因素及其程度存在差异。     

MULTIPLE CRITERIA ANALYSIS FOR WATER QUALITY MANAGEMENT IN THE NITRA BASIN1

ABSTRACT: This paper presents the implementation of one element of a decision support system (DSS) for regional water quality management, applied to the Nitra River Basin in Slovakia. A model-based, aspiration-led methodology for multicriteria decision support has been used for the study. Several reusable, modular software tools have been developed and implemented: a problem-specific generator to produce the core part of the mathematical programming model, tools for the generation and interactive modification of multicriteria problems, and a solver for the resulting mixed-integer optimization problem. Provided in the paper are the following: a complete formulation of the mathematical model (including the imbedded water quality model), a summary of the aspiration-reservation-led multiple criteria optimization approach applied to decision support, and an overview of results that illustrate the applied approach and provide some interesting insights to the case study.     

Public Participation and Effective Water Governance at the Local Level: A Case Study from a Small Under-Developed Area in Chile

The concept of participation in rural development has been evolutionary for the past two decades with those involved, such as development agencies and governments, particularly in rural water supply, re-evaluating their active role. The move towards effective community participation has encouraged a shift from the traditional top-down to a bottom-up approach whereby there is a decentralisation of unevenly distributed resources and power to empower a community and allow mobility of ‘people participation’. The Molinos water project is the first large-scale development project of its kind introduced into the village of Molinos in an under-developed area of Chile, where there has been no tradition of people participation. The project objective was to implement a low technology, low budget water treatment plant to the village of Molinos. Various aspects have hindered the continued development of the project including both technical and financial. In terms of people participation, the initial approach used was the top-down approach. There was a failure to fully integrate the community or inform the community in a formal manner about the project and consult them regarding key project issues. This case study illustrates that the lack of comprehensive consultation and the low level of participation of the community on the participatory scale does not achieve much in terms of people-centred benefits. For governance at the local level to be effective, participation should be inclusive and communicative so as to enhance transparency throughout the project lifetime. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.