膜生物反应器处理生活污水的实验研究和工程设计

通过浸没式膜生物反应器处理生活污水的实验研究,在给定气水比、停留时间、污泥负荷、污泥浓度、膜出水工作压力等设计参数的条件下得出膜生物反应器对有机物、氨氮的去除效果以及洗膜的方法。并以工程实例介绍膜生物反应器（MBR）处理生活污水的设计与计算方法。     

氯气干燥工艺的改进与优化

为解决原离子膜烧碱项目中氯气处理工艺存在的问题,在新建的20万t/a离子膜烧碱项目中采用2种塔型串联的氯气处理模式,并计算和绘制了塔的负荷性能图。按照负荷性能图对操作系统进行了优化。实践证明,改进后的干燥系统操作稳定,不但使处理后的氯气质量达到工艺指标,而且大大降低了浓硫酸的用量。既降低了生产成本,又减少了排放量。     

斜板沉降器及油水体系的分离研究

介绍了斜板沉降器的结构特性及处理负荷与结构尺寸、体系物性的关系。实验研究了苯水体系在不同分散相浓度下 ,斜板间距和板倾角与沉降器比负荷及容积利用效率的关系 ,表明对一定的分散带厚度、板间距、板倾角存在着最宜设计。     

液滴在斜板层膜上聚结时间的计算

在对聚结过程和分离界面处液滴与层膜流体力学特性分析的基础上,建立了单个液滴在斜板层膜上聚结时间模型,模型计算值与BlassE等人报道的实验结果误差小于10％。     

CO_2汽提塔的计算与分析

利用液体穿孔的流量公式,推导出CO_2汽提塔液体分布器上的液体分布孔流速与液位高度的关联公式,可计算出汽提塔单管负荷。根据湿壁塔内液膜厚度公式,计算出尿素-甲铵液在不同类型CO_2汽提塔中的停留时间。通过热力学计算,归纳总结了不同生产负荷下CO_2汽提塔的热负荷和传热系数。计算结果表明,理论计算值与实际生产数据基本吻合。     

斜板沉降器的分离特性及实验研究

介绍了斜板沉降器的分离特性及结构原理，通过实验研究了斜板沉降器的板间距、板倾角等结构参数对处理负荷的影响，同时提出了结构参数的一般设计原则，为斜板沉降器的工业化设计提供了理论及实验依据     

峰谷用电负荷调整的经济效益分析

探讨了离子膜电解槽采用峰谷分时用电负荷调整的可行性,制定出峰谷分时用电负荷调整方案.计算不同方案的经济效益,指出执行峰谷分时用电负荷调整时的注意事项.     

温度与负荷对厌氧膜生物反应器运行特性的影响研究

研究了浸没式厌氧膜-生物反应器(AnMBR)在35、25℃以及高COD负荷(3.0 kg/(m~3·d))、低COD负荷(1.5 kg/(m~3·d))4种工况下对污水的处理效果及膜运行特性。结果表明,温度是影响AnMBR膜运行特性最主要的因素,其次是有机负荷。中温低负荷有利于AnMBR的长期稳定运行,膜污染速率最低。4个工况的COD去除率均达到90%以上,其中,低负荷运行的AnMBR启动到稳定的时间最短。温度对表观甲烷产率有一定的影响,而有机负荷的影响较小;中温、低负荷运行的污泥粒径较常温、高负荷运行的小,较高的温度导致更小的颗粒粒径和较低的污泥黏度,使得膜孔阻力增加;滤饼层阻力占膜总阻力的90%以上,蛋白质是膜的溶解性污染物主要成分。     

精密过滤+气态膜分离法处理线路板生产氨氮废水研究

介绍了一种线路板企业排放的氨氮废水膜分离法处理装置,该处理装置包括由左向右依次连接设置的一级pH调节系统、精密过滤器、一级膜处理系统、二级pH调节系统、二级膜处理系统。一级pH调节系统和二级pH调节系统结构相同,一级膜处理系统和二级膜处理系统结构相同。该装置减少企业后端污水处理设施氨氮负荷,保障线路板企业氨氮废水达标排放。     

停机过程中锅炉高温受热面蒸汽侧氧化膜的应力分析

电站锅炉高温受热面蒸汽侧氧化膜在机组停机降负荷时可能发生脱落,对安全性构成严重威胁。通过建立有限元分析模型,对锅炉停机过程中受热面蒸汽侧氧化膜内的应力进行了计算和分析。对铁素体合金和奥氏体合金进行了研究,其中铁素体合金以T91为代表,奥氏体合金以TP347H为代表。通过对各应力分量以及von Mises等效应力进行分析,揭示机组降负荷过程中两种合金管蒸汽侧氧化膜内应力的变化规律,阐明两种合金管蒸汽侧氧化膜可能的失效模式,同时得出了铁素体合金管和奥氏体合金管蒸汽侧氧化膜分别在负荷降低后期和初期容易发生脱落的结论。     

A theoretical model of a free flow solution over an inclined long flat plate solar still

This analysis is used to investigate a free flow inclined flat plate solar still.To study the effect of significant parameters on a laminar falling liquid solution over an inclined long flat plate solar still, a mathematical two dimensional flow analysis is carried out based on continuity, momentum and energy equations for liquid and vapor phases together with the interface. As far as the liquid film is concerned, the velocity, film thickness, pressure, temperature and the hourly evaporated water volume profiles are found. It is shown that the significant parameters which affect the solar still are the initial film thickness (i.e, the initial mass flow rate), the plate inclination, the still length and the absorber heat flux (i.e., the solar radiation reaching the plate). It is also shown that the variation in liquid film thickness down the still has a significant effect on the evaporation rate (i.e., the condensed water) and should not be neglected particularly in the case of a long inclined solar still.     

Etude numérique de l'influence de l'inclinaison sur l'évaporation d'un film liquide s'écoulant sur une paroi plane isotherme ou à flux de chaleur imposé

The authors study numerically, by using an implicit centred difference method with non-uniform grid, the effects of inclination on the evaporation of liquid film flowing on a horizontal or inclined isotherm flat plate with the assumption of existing two-dimensional laminar boundary-layers with variable physical properties. In the case of an humid air-water system, they compare their results with those of other authors and study the influence of the entrance air velocity and the inclined angle of plate. They show that for an isotherm plate, the inclined angle effects heat and mass transfer, especially for low flow air velocity and for an inclined angle less than 10°. In this domain, the interfacial temperature is so high as the inclined angle increases which causes an increase of the density of flux of vapor, of the latent heat of vaporization and a reduction of draining length. For the heated plate, it is always for an inclined angle than 10°, that the effects of this parameter and air velocity are very important on the film thickness and its interfacial velocity. Opposite to the case of an isotherm plate, air velocity increase causes a reduction of interfacial temperature; inclined angle has less effect on temperature, density of latent heat of vaporisation and on heat and mass transfer at the interface. Generally, for an isotherm or heated plate, heat transfer is dominated by liquid-vapor phase transition.     

EXPERIMENTAL STUDY OF GRAVITY-DRIVEN FILM FLOW OF NON-NEWTONIAN FLUIDS

In this research the problem of a thin layer of a power law liquid falling down an inclined plate was studied experimentally. Three different carboxymethyl cellulose (CMC) solution concentrations (1.1%, 1.5%, and 2%), which are extensively used in industry, have been selected as the operating fluid, and their rheology, surface tension, and contact angle have been determined. Dynamics of the falling film has been studied by image acquisition techniques, and by using image processing methods the velocity of falling film, film thickness, and the shape of the falling film have been investigated. The inclined plate with different inclination angles φ (0 < φ < π/2), and nonidentical surfaces (ceramic, aluminum, and glass) were used to study the effect of inclination, rheological properties, and contact angle on the vital parameters mentioned earlier. These variables are embedded in dimensionless groups, Weber (We), Reynolds (Re), and Froude (Fr) numbers, and some correlations were devised to relate dimensionless velocity distribution parameters and film thickness to these dimensionless groups.     

拦截斜板沉降技术研究

拦截斜板沉淀是一项集拦截、斜板沉淀技术优点于一体的新型水处理工艺与技术。该文以章江水加高岭土配制而成的水为研究对象，研究了拦截斜板沉淀随运行时间的延长后的处理效果。结果表明．拦截斜板沉淀能很好地解决拦截沉淀技术中由于运行时间的增长而出现出水浊度上升的问题．同时指出下一步研究中应注意或急需解决的问题。     

波纹壁面上流动液膜涡的生成特性

针对液膜在非平整壁面上流动过程中生成涡的现象,基于VOF方法,采用FLUENT软件模拟了三维波纹壁面上的液膜流动。研究了波纹结构内涡结构的演化过程,分析入口Reynolds数、波纹结构、壁面倾角、流体黏度和表面张力对波纹结构内涡结构的影响。结果表明：随着时间的演化,涡的大小和形状不断变化,最终达到稳定。且涡结构变化对自由液面的波动影响显著。较低Re和波形度时,波纹结构内不易形成涡,随着Re和波形度增大,产生涡且涡呈增大趋势,涡的形态也随之改变,自由液面位置升高,其相位滞后于波纹壁面。当壁面倾角改变时,波纹结构内的涡特性变化较大,液膜厚度略有增加,而自由液面相位不明显。表面张力对涡结构有显著影响,液膜流动过程中不容忽视。流体黏性改变时,波纹结构内涡的大小和形状无明显的变化。黏度变小和忽略表面张力时,液膜厚度均变薄。以上结果为工业设备生产、运行和设计提供了一定参考依据。     

An analysis of laminar forced convection film boiling

A study of forced convection film boiling on a horizontal isothermal plate is made using a treatment based on boundary layer theory. For the vapour, the velocity and temperature distributions are obtained from equations of motion and energy. For the liquid layer, the Howarth approximation for flow over a plate is used. Then, by employing interface matching conditions, the significance of the rhμ ratio between the vapour and the liquid on the variation of Nusselt number is examined.     

Etude numérique de l'évaporation dans un courant d'air humide laminaire et turbulent d'un film d'eau ruisselant sur une plaque inclinée

The authors have proposed an appropriate model based on the liquid film transfer equations which are one‐dimensional, partially two‐dimensional and two‐dimensional. They have compared their results with those of other works and studied the influence of the liquid mass flow rate and the inclined angle. They have shown that the interracial heat transfer is dominated by the latent heat transfer; the contribution of the sensible heat is only important in the turbulent region where the interfacial temperature and the evaporating mass flux are practically constant and the thickness of the liquid film is uniform. For the adiabatic plate, the liquid mass flow rate and the inclined angle have no influence on the transfers. For the isothermal or the heated plate, the liquid mass flow rate essentially influences the turbulent region by reducing the interrfacial temperature and the heat and mass transfer coefficients. However, the inclination angle affects mainly the laminar region by increasing the interfacial velocity, reducing the film thickness and has little effects on the transfer coefficients.     

倾斜波纹板上液膜流动的CFD研究

利用VOF法建立了液膜在倾斜波纹板上的气-液两相流CFD模型,并根据液膜流动特点提出了表面张力动量源项和气液界面作用力动量源项.模拟结果与文献实验值吻合较好,表明本文提出的CFD液膜流动模型具有一定的可靠性.通过模拟不同性质的液体在不同表面结构波纹板上的流动过程发现,波纹板表面微观结构以及液体性质尤其是液体的表面张力对连续液膜的形成有重要作用,表明通过改变波纹板面微观结构以及降低液体的表面张力可以促进连续液膜的形成,对提高气液之间的传质效率有重要意义.