《海水预处理ppt课件.ppt》由会员分享，可在线阅读，更多相关《海水预处理ppt课件.ppt（20页珍藏版）》请在三一办公上搜索。
1、海水预处理系统 Sea Water Pretreatment System,西北发电运行有限责任公司Shaanxi Northwest Power Generation Operation Co., Ltd.,海水预处理系统流程Sea Water Pretreatment System Flow,海水预处理设备图示Graphic Display of Sea Water Pretreatment Equipment,孔板式净水混合器设备图示Drawing of Orifice Plate Purified Water Mixer,海水预处理设备图示Graphic Display of Sea
2、Water Pretreatment Equipment,小孔眼格网设备图示Drawing of Small orifice Grids,海水预处理设备图示Graphic Display of Sea Water Pretreatment Equipment,小间距斜板设备图示Drawing of Small-Spacing Skew Plate,海水预处理设备图示Graphic Display of Sea Water Pretreatment Equipment,自动冲洗过滤器设备图示Drawing of Automatic Flushing Filter,海水预处理设备图示Graphic
3、 Display of Sea Water Pretreatment Equipment,沉淀池设备外形图External view of sedimentation basin equipment,混凝原理Coagulation Principle,凝聚和絮凝的全过程称为混凝。The whole process of coagulation and flocculation is called coagulation.（1）胶体的脱稳凝聚(1) Destabilization and coagulation of colloid向水中投加电解质，可起到压缩双电层使胶体脱稳的作用。其主要机理是
4、向水中加入铝盐或铁盐混凝剂后，水中胶体颗粒的双电层被压缩或电性中和而失去稳定性。将混凝剂与原水快速均匀混合并产生一系列化学反应而脱稳，这一过程所需时间很短，一般在1min左右。一些阳离子型的高分子聚合物也能对水中胶体起到脱稳凝聚作用，这类高分子聚合物在水中呈长链结构，带有正电荷，它们对水中胶体的脱稳凝聚是由于范德华力吸附和静电引力共同作用的。,Putting electrolyte into water can play a function of compressing electric double layer to cause colloid to lose stability. The
5、 main mechanism is electric double layer of colloidal particles lose stability because they are compressed or their electrical properties are neutralized after aluminum salt or ferric salt coagulant is added in water. Mix coagulant with raw water evenly and quickly to produce a series of chemical re
6、actions to get the purpose of destabilization; this process needs a short time which is generally 1 min. or so. Some cation type macromolecule polymers can have the effect of destabilization and coagulation on colloid in water. This type of macromolecular polymers are in a long chain structure in wa
7、ter and have positive charges. The destabilization and coagulation effect on colloid by macromolecular polymers are done by Van der Waals force absorption and electrostatic attractive force together.,混凝原理Coagulation Principle,（2）絮凝和絮凝物（矾花）的形成(2) Formation of flocculation and floc 水中胶体经脱稳凝聚形成的初始絮凝物的粒
8、径一般在1m以上，这时布朗运动已不能推动它们碰撞而形成更大的颗粒。为了使初始絮凝物互相碰撞而粘合成大颗粒的絮凝体，需要另外向水中输入能量，产生速度梯度。有时需向水中加入有机高分子絮凝剂，利用絮凝剂长链分子的吸附架桥作用提高碰撞产生粘合的几率。絮凝效率通常随絮凝物浓度和絮凝时间的增加而提高。,The particle size of initial floc formed through destabilization and coagulation of colloids in water is generally more than 1m; Brownian movement could n
9、ot drive them to collide with each other to form bigger particles at this time. In order to initial floc collide with each other to agglutinate big floc, energy needs to be put in water additionally to produce velocity gradient. Sometimes, organic macromolecular flocculent needs to be added in water
10、 and make use of the absorption and bridging function of long-chain molecules of flocculent to improve the probability of agglutination production because of collision. Flocculation efficiency is improved with the increases of the floc concentration and flocculation time.,常用的混凝药剂简介Brief Introduction
11、 of Common Coagulants,为了提高混凝处理的效果，必须选用性能良好的药剂，创造适宜的化学和水力学条件。常用的混凝剂主要分为铝盐和铁盐两类，铝盐中以硫酸铝和聚合铝为主，铁盐中以三氯化铁和聚合硫酸铁居多。铁盐与铝盐相比，铁盐生成的絮凝物密度大，沉降速度快， pH适应范围宽；混凝效果受温度的影响比铝盐小；但投加铁盐时要注意，设备运行不正常时，带出的铁离子会使出水带色，并可能污染后续水处理除盐设备，如阴离子交换树脂。,In order to improve coagulation treatment effect, it must choose chemicals with good
12、 performances and create suitable chemical and hydraulics conditions. Common coagulants are mainly divided into aluminum salt and ferric salt two types. Aluminum sulfate and polymeric aluminum take a priority in aluminum salt; ferric chloride and polymeric ferric sulfate take a main part in ferric s
13、alt. Comparing with aluminum salt, the density of floc produced by ferric salt is big; the sedimentation velocity is fast; pH application range is wide; the influence caused by temperature on coagulation effect is weaker than that of aluminum salt. However, it should notice that iron ions taken out
14、will cause water to have color and might pollute sequential water treatment demineralization equipment such as anion exchange resin if the equipment is in abnormal operation during adding ferric salt.,常用的混凝药剂简介Brief Introduction of Common Coagulants,常用的混凝药剂简介Brief Introduction of Common Coagulants,常
15、用的混凝药剂简介Brief Introduction of Common Coagulants,常用的混凝药剂简介Brief Introduction of Common Coagulants,当由于原水水质等方面的问题，单独采用混凝剂不能取得良好的效果时，需要投加一些辅助药剂来提高混凝处理效果，这种辅助药剂称为助凝剂。助凝剂分无机类和有机类。在无机类的助凝剂中，有的用来调整混凝过程中的pH值，有的用来增加絮凝物的密度和牢固性。典型的无机助凝剂有氧化钙、水玻璃、膨润土；有机类的助凝剂大都是水溶性的聚合物，分子呈链状或树枝状，其主要作用有：离子性作用，即利用离子性基团进行电性中和，起絮凝作用；利
16、用高分子聚合物的链状结构，借助吸附架桥起凝聚作用。典型的有机助凝剂有聚甲基丙烯酸钠、聚丙烯酰胺（PAM）等。,Using coagulant individually can not get a good effect due to water quality problem of raw water and so on, so some assistant chemicals are added to improve coagulation treatment effect; this kind of assistant chemical is called coagulation aid.
17、 The coagulation aid is divided into organic type and non-organic type. Some of non-organic type coagulation aids are used to regulate pH in the coagulation process while some are used to increase the density and firmness of floc. Typical organic coagulation aids include calcium oxide, water glass a
18、nd bentonite; most of organic coagulation aids are water-soluble polymers whose molecules are in a chain shape or dendritic shape; the main functions are: ionicity function which is namely using ionicity group to make electrical property neutralization to playa flocculation function; using the chain structure of macromolecular polymer with the help of absorption and bridging to play a coagulation function. Typical organic coagulation aids include sodium polymethyl acrylic acid and polyacrylamide (PAM), etc.,
