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991.
High-quality potable water can be produced at a reasonable cost if reverse osmosis (RO) technology is applied to renovate secondary/tertiary urban wastewater effluent. Such implementation would yield many advantages to Kuwait, namely: satisfying the increasing agricultural, industrial and domestic demands for good quality water that is free from viruses and bacteria and other microbials present preserving the natural strategic water resources; reducing the environmental pollution resulting from the direct discharge of secondary/tertiary municipal effluents to the sea; and meeting unexpected emergency cases of shortages in freshwater produced from the desalination of seawater for certain domestic applications. The main aims of this work are to assess the technical viability and the economic feasibility of implementing RO technology to renovate Kuwaiti wastewater treated effluent. The paper describes the design of pretreatment, experimental set-up, results, and data analysis of desalinating municipal wastewater by RO. The results indicate that wastewater can be treated to produce an excellent permeate quality almost devoid from salts and pollutants. 相似文献
992.
Bing H. Chen 《Chemical engineering science》2007,62(12):3178-3184
In this paper, we have integrated process characterisation and reaction kinetic data for a transketolase catalysed carbon-carbon bond formation to build a comprehensive reaction model. Based on the synthesis of erythrulose from β-hydroxypyruvate and glycolaldehyde, the model includes component degradation as a function of time and concentration as well as glycolaldehyde toxicity towards the enzyme. Using the ratio of initial substrate concentration as a process variable, simulations and analysis based on this model allowed process options to be evaluated. The model links bioconversion to upstream fermentation for enzyme production and downstream product purification and this could provide guidelines for process development. 相似文献
993.
Recent development of the dynamic analysis technique has made it possible to measure separately kinetic parameters of a catalytic reaction as well as to study the effect of catalyst preparation parameters. But its application is still limned to first-order reaction. This work is aimed to demonstrate in some detail that,by comparison of the reaction rate expressions with the two-step mechanism used in catalytic kinetics and dynamic analysis, these methods can be extended to non-first-order reaction, and the kinetic parameters measured by dynamic techniques are interpreted for different reaction mechanisms. 相似文献
994.
石油化工装备的失效,由于所处理的物料常常是易燃易爆的化学品,所以往往导致发生燃烧、爆炸等,还可以波及附近的其它装置和设备发生连锁的失效和爆炸。为了分析这种严重事故可能造成的影响,研究防止这种事故的发生,近年来研究和发展了一种定量估计这种失效后果严重程度的方法,称为后果分析(Consequence Analysis)。通过分析,从这些设备的失效概率、可能发生的失效形式,研究设备内物料的泄漏形式、可能发生的后果、影响范围的大小、对周围装置、环境和人员的危害程度等,从而提出在设备设计、工厂的总图设计中采取的措施,以减轻其危害的程度。 相似文献
995.
996.
Small angle scattering (SAS) techniques offer a number of advantages for the investigation of the nature and behavior of porous materials. In particular, with respect to carbons, the essentially non-intrusive nature of SAS means that along with the more traditional, pre- and post-treatment characterization of carbons, in principle, characterization can also be performed in situ during adsorption and activation processes. In the current communication, the application of the techniques of small angle X-ray (SAXS) and neutron (SANS) scattering is reviewed specifically with respect to porosity characterization in carbons. First, the basis of these techniques is presented. More recent applications of SAXS and SANS to carbon porosity are presented, and their relative attributes are contrasted, including the related technique of contrast matching with SANS to distinguish “closed” from “open” porosity, and its application to elucidation of pore development mechanisms. Applications of other related techniques, such as μSAXS and TGA/SAXS, to carbon characterization and porosity development are also discussed. 相似文献
997.
阐述催化裂化装置5×104t/aFCCU技改为7×104t/aARGG的技改内容及工艺特点,并对装置运行现状进行分析。重点就进一步提高液化气收率以及稳定、优化装置长周期、高效运行进行探讨、研究。 相似文献
998.
999.
如何在众多污水处理厂PPP项目中挑选出风险低、回报适宜的优质项目不仅是社会资本方关注的重点,也是推动PPP项目顺利开展的关键。从社会资本方的角度出发,建立政府能力及环境、项目特征、项目影响3个方面的较为完善的污水处理厂PPP项目评价体系,采用聚类分析法从类别内、类别间两方面综合计算专家权重,以此修正AHP法确定的指标权重,并结合TOPSIS模型对众多污水处理厂PPP项目进行比较,优选出最适宜投资的项目。通过实例验证,此方法可行、有效,且社会资本方对项目特征、政府能力及环境两方面非常重视。 相似文献
1000.
基于KPCA-PSO-SVM的径流预测研究 总被引:1,自引:0,他引:1
为提高径流预测模型的准确性与稳定性,对KPCA-PSO-SVM的径流预测方法进行了研究。在分析径流影响因素的基础上,利用核主成分分析(KPCA)法对径流影响因子进行非线性特征提取,获得主成分作为支持向量机(SVM)的输入变量,建立了径流预测SVM模型,其中模型参数通过粒子群算法(PSO)进行优化。模型建立后,以新疆伊犁河雅马渡站中长期径流预测为例进行分析。预测分析结果表明,在拟合和检验阶段模型的平均相对误差分别为0.77%和7.64%,与其他预测模型比较,基于KPCA-PSO-SVM方法建立的径流预测模型有较好的预测和泛化能力,是一种行之有效的中长期径流预测方法。 相似文献