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天然水中当含有过量的钙,镁离子时,对人体有在,不能直接用作饮用水,应先进行软化,为了提高饮用水的质量,常用膜分离及离子交换等软化方法,由于膜分离法尚存在一一弱点,本文提出一种适合家用的离子交换处理方法。 相似文献
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《中国石油和化工标准与质量》2016,(18)
本文以高硬度饮用水作为研究对象,探讨流动注射分析仪测定高硬度饮用水中的挥发酚及相关问题。首先对流动注射分析仪下的测定标准进行了简要概述;主要是以我国北方地区的硬度水硬度过高而对其进行针对性研究;采用的方法是实验法,并根据现有实验中的具体情况,对原来的实验方法做了一些小的改进。希望能够通过本文初步论述可以引起更多的关注与更为广泛的交流,从而为高硬度饮用水中的相关指标的测定提供一些有价值的信息,以供参考。 相似文献
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根据钢铁厂外排水质高硬度低碱度的特征,采用石灰-纯碱和复配型絮凝剂的化学沉淀方法对该种废水进行处理,达到了钢铁厂废水循环回用的水质和成本要求.通过静态和动态试验确定了合理的组合处理工艺及条件. 相似文献
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以阜阳市某生活垃圾填埋场渗滤液为研究对象,针对渗滤液高硬度、低碱度的特点,考查软化+微滤膜中试工艺对填埋场总硬度的处理效能,分析微滤膜运行参数对膜通量和产水流量的影响.中试结果表明:软化+微滤膜工艺可有效去除水源中钙镁离子污染问题,控制软化装置的反应池pH在11.5,总硬度(以CaCO3计)的去除率在94%以上,出水总硬度(以CaCO3计)稳定<100 mg/L.软化微滤工艺对渗滤液中COD的平均去除率为16.2%.单支微滤膜正常运行,反洗频率30 min时,可将膜通量恢复至初始通量的90%以上.由中试可知,微滤膜具有良好的抗污染性能,在进膜污泥浓度为4.97 g/L及以上时,初始膜通量仍能保持较高值. 相似文献
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石灰软化-絮凝法处理地下水硬度动态中试试验研究 总被引:1,自引:0,他引:1
采用石灰软化-絮凝法处理华南地区某水厂地下水硬度。动态中试试验采用一体化处理装置,考察石灰软化工艺运行效果,并进一步探索石灰投加量和PAC投加量对试验效果的影响。试验结果表明,Ca(OH)2投加量为299.1361.3 mg/L、PAC投加量为43.6361.3 mg/L、PAC投加量为43.648.7 mg/L,处理效果较佳。处理后总硬度(以CaCO3计)降到110mg/L,总碱度(非碳酸盐碱度)降到80 mg/L,符合GB 5749—2006《生活饮用水卫生标准》要求。基于基础设施、设备投资和运行成本的分析表明,石灰软化工艺较离子交换工艺的制水成本减少0.457元/t。 相似文献
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A comprehensive review of nanofiltration membranes:Treatment, pretreatment, modelling, and atomic force microscopy 总被引:8,自引:0,他引:8
Nanofiltration membranes (NF) have applications in several areas. One of the main applications has been in watertreatment for drinking water production as well as wastewater treatment. NF can either be used to treat all kinds of water including ground, surface, and wastewater or used as a pretreatment for desalination. The introduction of NF as a pretreatment is considered a breakthrough for the desalination process. NF membranes have been shown to be able to remove turbidity, microorganisms and hardness, as well as a fraction of the dissolved salts. This results in a significantly lower operating pressure and thus provides a much more energy-efficient process. Similar to other membrane processes, a major problem in NF membrane applications is fouling. Several studies have investigated the mechanisms of fouling in NF membranes and suggested methods to minimize and control the fouling of NF membranes. For NF membrane characterizations and process prediction, modeling of NF processes and the use of atomic force microscopy (AFM) are very important. The ability to predict the performance of NF processes will lead to a lower number of experiments, saving of time and money, and help to understand the separation mechanisms during NF. A comprehensive review of NF in water treatments is presented including a review of the applications of NF in treating water as well as in the pretreatment process for desalination; the mechanism as well as minimization of NF membrane fouling problems; and theories for modelling and transport of salt, charged and noncharged organic compounds in NF membranes. The review will also address the application of AFM in studying the morphology of membrane surfaces as part of the NF membrane characterization. 相似文献
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针对天津北辰双口村的高氟水,分别考察NF270和NF90卷式纳滤膜脱氟效果。结果表明,NF90纳滤膜对F-具有较好的去除效果,截留率最高达93%;NF270纳滤膜对F-的脱除率最高为45%。NF90在处理农村高氟水上具有工业应用价值。 相似文献
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Both reverse osmosis (RO) and nanofiltration (NF) membranes have been increasingly used for water purification and desalination. However, the salt rejection of NF membranes is quite different from that of RO membranes, which makes a significant distinction in their process designs. This work started from the performance investigation of a single NF membrane element and then focused on the process design of the NF system for surface water treat-ment. In experimental tests, it was found that the observed rejection of the NF element becomes nearly constant when the concentrate flow is large enough, while the membrane flux of the NF element is quite stable regardless of the water flow across the membrane surface. These findings can be used to instruct the process design of the NF system for surface water treatment. In process design, a two-stage arrangement is sufficient for the NF system to reach the highest water recovery, while the RO system requires a three-stage arrangement. 相似文献
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纳滤工艺对铅锌冶炼工业废水的回用处理 总被引:1,自引:0,他引:1
针对铅锌冶炼废水外排水含盐量高、结垢倾向严重并含有重金属的水质特点,采用纳滤工艺对其进行回用处理,纳滤进水压力为0.6~0.75 MPa,系统回收率为75%,脱盐率为92%~95%,产水水质优于循环水水质标准可直接回用于厂区工业用水系统.浓水采用强化混凝工艺处理可迭标外排.介绍了纳滤工艺及其预处理工艺,浓水处理工艺,并对其运行情况及存在问题进行了总结分析. 相似文献
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纳滤工艺被广泛应用于分散式饮用水深度处理,能解决饮用水苦咸化,盐碱化或微污染等常规水处理工艺无法规避的用水风险,在长时间运行过程中还能有效应对重金属等突发污染风险。但重金属污染易加重纳滤膜污染,需要增设预处理装置加以缓冲,实现纳滤装置的长久稳定运行。而天然沸石具有良好的筛分性能和吸附性能,能够有效缓冲重金属对纳滤装置的冲击。试验以重金属铜为例,证明水中铜离子会造成纳滤不可逆污染比例增加,不利于系统稳定运行;天然沸石对铜离子有很好的吸附效果,静态吸附试验表明天然沸石对水中铜离子的最大吸附量为3.03 mg/g,通过正交试验合理设计吸附预处理,能够有效为纳滤工艺提供安全进水,保证纳滤进水铜离子浓度低于10 mg/L。实践工艺中,吸附预处理能有效缓解纳滤膜不可逆污染,而且吸附-纳滤组合工艺对铜离子及部分其他重金属离子表现出良好的处理效果。 相似文献
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The application of different nanofiltration membranes for the separation of pesticides, i.e., atrazine and dimethoate, from aqueous solutions is described. The nanoflitration membranes DK, NF270, NF200, and NF90 were tested for the pesticide retention performance in a stirred dead‐end filtration system. NF90 demonstrated the best pesticide retention with over 95 % for atrazine and approximately 80 % for dimethoate. All membranes consistently showed better retention of atrazine than of dimethoate. Dissolving the pesticides in river or tap water amplified the overall pesticide retention performance, indicating that filtration in water treatment plants could render superior pesticide retention. However, a lower flux was obtained for the filtration of tap and river water. 相似文献
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集成膜技术处理微污染水的工艺研究 总被引:1,自引:1,他引:0
采用0.45μm微滤膜、不同截留分子质量的超滤膜(100、80、50,30.10、5 kDa)以及不同型号的纳滤膜(NF90、NF270、NF70)为试验用膜,并将这些膜进行优化组合,直接处理浙江省某流域河水.结果表明,采用0.45μm微滤膜、截留分子质量5kD的超滤膜作为预处理工艺,经NF90处理后,COD_(Mn)去除率达到89%,离子的去除率达到83%.采用直接膜处理工艺,可用微滤、超滤替代传统给水处理中的混凝、过滤、沉淀及澄清处理等微污染水预处理工艺,集成膜分离技术能很好地实现对微污染原水的彻底处理,出水水质稳定安全,完全达到健康饮用水标准. 相似文献