浅除盐水处理技术的应用

从小氮肥厂的应用人手,介绍了浅除盐水处理技术特点.结果表明,该技术在工业锅炉上推广应用,具有安全、经济的效果.     

应用夹点技术确定再生水用量

工业节水及废水减排已成为过程工业持续发展的前提之一。运用目标导向的夹点分析技术对过程用水网络系统进行系统地分析,可确定过程用水、再生水用量和废水排放量的最小目标。以固定再生出口浓度为基准,提出基于累积流量-累积污染质量负荷组合曲线图的夹点分析方法来确定用水网络的最小再生水流量,并给出了详细计算步骤和案例验证。     

Raw water pre-treatment methods in pharmaceutical water systems

The use of pre-treatment methods for the raw water used to produce pharmaceutical grade water is growing in popularity, especially when it results in better operating reliability and a longer operating lifetime of the downstream treatment plant and equipment. Andreas Müller and Thomas Menzel, Christ AG, Switzerland, discuss the background to pre-treatment, and explain when such systems are necessary and why membrane-based methods, and ultrafiltration in particular, can offer a number of advantages when it comes to the pre-treatment of raw water.     

基于梯级用水的工业水系统节水优化研究

水系统节水优化是一种从系统层面分析水系统节水潜力的方法,借助数学模型可实现节水的量化研究。阐述了一种基于外排水再利用的水系统节水优化模型,并利用Vogel方法实现模型的求解。以火电企业为典型用水案例进行研究,将案例企业用水系统划分为6个子系统(循环冷却水系统、灰渣水系统、化学除盐水系统、脱硫用水系统、生活消防用水系统、其他杂用水系统),在污水排放改造的基础上构建了基于成本最优的节水优化模型并进行了求解。经案例研究发现,优化带来的经济效益最为明显,其次是节水、生态效益。案例企业优化后综合发电耗水、总用水成本、新鲜水取用量降幅分别为10.3%、13.6%、11.2%,对缓解当地水环境污染以及地下水开采压力具有积极意义。     

Drinking water from sea water by forward osmosis

Potable water may be extracted from a saline source, such as the ocean, using a concentrated solution of nutrients and a semipermeable membrane. This paper applies the previously presented theory (1) of the forward osmosis extractor to this case and compares that theory with experiment. Theory and experiment are found to match well. Calculated and observed magnitudes of water extraction rate and nutrient utilization indicate that practical devices may be constructed. It is found that the volume of water obtained per mass of nutrient meets the human requirement for fluids and nutrient. Optimization of the system is discussed.     

Ultrafiltration of lake water for potable water production

Ultrafiltration with coagulation or powdered activated carbon pretreatment is used to treat water from a public water supply. While UF without pretreatment is effective in removing turbidity, pretreatment prior to UF greatly enhances the removal of natural organic matter and trihalomethane precursors. Short-term flux loss can be minimized with backflushing, while long-term irreversible fouling seems to be affected most by the type of membrane polymer.     

某南水北调水源水厂净水工艺设计

某城区供水采用南水北调中线水源。根据该城区现状,以及进水水质条件和出水水质要求,经技术经济比较确定了预氧化-常规处理-预留深度处理的工艺方案。工程运行结果表明,出水水质完全符合GB 5749—2006《生活饮用水卫生标准》的要求。     

水质模型预测配水管网水质面临的问题与对策

受配水管网系统运行工况的复杂程度、建模方法的经验性及模型初始参数的不准确性等因素的影响,水质模型的预测结果具有一定的不确定性。通过采取控制模型初始参数、延时模拟校核或多工况校验、进行模型脆弱性评价等措施可以建立水质预测风险"防火墙",为帮助供水企业更广泛地应用模型预测水质提供了理论依据。     

Permeability of water and water vapor through cellulosic membranes

To elucidate the water transport mechanism through homogeneous membranes, water and water vapor permeation through crosslinked cellulose membranes, cellulose diacetate, and cellulose triacetate membranes are studied. It is found that the water flux increases with the degree of hydration; and as for cellulose membranes, the degree of hydration is an increasing function of the degree of crosslinking. Activation energy of hydraulic permeability (K_w) is not equal to that of purely viscous flow, and is smaller than that of the water vapor diffusion coefficient (D?) for all membranes. The free-volume concept relating the molar frictional coefficient to temperature and to degree of hydration explains reasonably the temperature dependence of hydraulic permeability and of water vapor diffusion coefficient and gives adequate values for the fractional free volume of the system. The critical volume V^*, appearing in the Cohen-Turnbull expression between friction coefficient and free volume fraction, may be considered as the size of the cluster of water molecules. The value of V^* in the case of hydraulic permeability is larger than that for water vapor diffusion by several times. Furthermore, the value V^* increases with increase of degree of hydration for water permeation and water vapor diffusion.     

具有中水道的过程工业水网络设计方法

提出了一种具有中水道的过程工业水网络设计方法,该方法强调合理地确定第一中水道位置的重要性,运用一种确定某一中水道回用到它的后续过程的优先顺序的新方法精确地完成了从任意一个中水道到它的后续过程的水分配,并在设计步骤中给出了一些可能出现情况的处理方法.实例求解结果表明,具有中水道的水网络能明显减少新鲜水的消费,设计方法简便易行.     

自来水及其水源中的内分泌干扰物质

残留在自来水中的内分泌干扰物质的来源主要包括水源污染,配水管网及这些化合物质在氯消毒过程中的副产物,水源中检出频率较高的是壬基苯酚,双酚A、4-t-辛基苯酚、邻苯二甲酸乙基已基酯及来自人畜的雌酮,配水管网中的物质主要是作为塑料添加剂的壬基苯酚,双酚A等,在氯消毒过程中,双酚A及NP可以分解产生多种副产物,用酵母Two-hybrid法对这些副产物的内分泌干扰作用进行了研究,表明双酚A的副产物具有雌激素协同作用,而NP的副产物则具有雌激素拮抗作用,检测出我国某河流及自来水的内分泌干扰活性。     

优化循环水工艺综合利用水资源

对循环水系统用水平衡分析后,进行了工艺优化改造,实现了水资源的综合利用。