给排水专业英语Unit7

Reduction half reaction？
equation----two-electron change
7.3 Important sentences
1. 2.
(第四段) Half-reaction potentials 无穷的，无限的 Because of the almost infinite number of possible reactions, there are no summary tables of equilibrium constants for oxidation-reduction reactions. Of the many properties that can be used to characterize oxidation-reduction reactions, the electrical potential (i.e, voltage) or emf of the half reaction is used most commonly. Thus ,every half reaction involving an oxidation or reduction has a
6
1.
基本概念 (第一段) Included in the following discussion is an introduction of the fundamental concepts 概述 involved in chemical oxidation, an overview of the uses of chemical oxidation in wastewater treatment , and a discussion of the use of chemical oxidation for the reduction of BOD and COD, 氨 the oxidation of ammonia ,and oxidation of nonbiodegradable organic compounds.
3.
The positive value for the E0 is taken as an indication that the reaction will proceed as written. The magnitude of the value, as will be illustrated subsequently, can be taken as a measure of the extent to which the reaction as written will proceed.
of residual organics,(2) control odors,(3) remove ammonia ,and (4) reduce the bacterial and viral content of wastewater. Chemical oxidation is especially effective for the elimination of odorous 硫醇 compounds (e.g., oxidation of sulfides and mercaptans). Now chemical oxidation is commonly used to (1) improve the treatability of nonbiodegradable (refractory) organic compounds,(2) eliminate the inhibitory effects of certain organic and inorganic compounds to microbial growth, 毒性 and (3) reduce or eliminate the toxicity of certain organic and inorganic compounds to microbial 水生植物 growth and aquatic flora. The chemical oxidation of BOD and COD, ammonia, and refractory organic compounds is considered in this section.
chemical oxidation reactions. The topics to be discussed include (1) oxidation-reduction reactions, 平衡常数 (2) half reaction potentials,(3) reaction potentials,(4) equilibrium constants for redox equations for redox equations, and (5) rate of oxidation-reduction reactions.
electromotive force
standard potential E0 associated with it.
3. 4.
（11-4）和（11-5）公式是否有错误？ The half –reaction potential is a measure of the tendency of a reaction to proceed to the right. Half reaction with large positive potential, E0, tend to proceed to the right as written. Conversely half reactions with large negative potential, E0 , tend to proceed to the left.
消毒 氯 入流 臭氧 氧化 还原 酶 催化剂 硫化物 苯
5


7.2 New words and expressions
Oxidant/Oxidizing agent 氧化剂


Reducer/Reducing agent 还原剂
Oxidation potential 氧化电势，氧化性 Reduction potential 还原电势，还原性 Advanced oxidation process 高级氧化工艺 (AOP) Hydrogen peroxide 过氧化氢 Ammonia 氨 Nonbiodegradable 不能生物降解的 Oxidation-reduction reaction 氧化还原反应
减轻，缓和
7.3 Important sentences
1.
(第六段)Rate
of oxidation-reduction reactions.
2.
As noted previously, the half-reaction potentials can be used to
predict whether a reaction will proceed as written. Unfortunately, the reaction potential provides no information about the rate at which the
快Baidu Nhomakorabea池
Gravity filter
Rapid filter
重力滤池
7.1 Words and expressions Review

Filter medium
过滤介质，滤料


无烟煤
煤-砂滤床 Dual media filter Coarse media Turbidity breakthrough
Specialized English for Water and Wastewater Engineering
给排水专业英语
主讲教师：李康
Lesson 7
Chemical oxidation
化学氧化
7.1 Words and expressions Review

Frictional resistance
7.3 Important sentences
nonbiodegradable organic compounds 难降解有机物有哪些？
oxidation and reduction (第二段) The purpose of the following discussion is to introduce the basic concepts involved in
whether a reaction comprised of two half reactions will proceed as written. The tendency of a reaction to proceed is obtained by determining the E0
reaction for the entire reaction as given by the following expression.
5.
The relationship between electrical potential and reaction?
7.3 Important sentences
1.
(第五段)Reaction
potentials
2.
The half-reaction potentials, discussed above , can be used to predict
Transition metal 过渡金属？ enzyme 酶 胃蛋白酶、胰酶、淀粉酶、消化酶
7.3 Important sentences
1. 2.
(第七段)Applications
In the past, chemical oxidation was used most commonly to (1) reduce the concentration
摩擦阻力


反冲洗
Backwashing
Interception [,intə'sepʃən] n. 拦截，截留 Electrokinetic [i,lektrəʊkai'netik] adj. 动电学的 ，电动的 Terminate [‘tə:mineit] Hydraulics ['hai'drɔ:liks] v. 终止，停止， 结束 n. 水力学
redox 氧化还原作用？
7.3 Important sentences
1. (第三段) Oxidation-reduction reactions（5min）
copper----Cu
zinc----Zn
Oxidation-reduction reactions
Oxidation half reaction？
reaction will proceed. Chemical oxidation reactions often require the
presence of one or more catalysts for the reaction to proceed or to increase the rate of reaction. Transition metal cations, enzymes, pH adjustment, and a variety of proprietary substances have been used as catalysts.
Anthracite
Coal-sand beds 双层滤料滤池 粗滤料 浊度穿透
Filter cycle
Filter effluent Filter influent
过滤周期
滤后水，滤池出水 滤前水，滤池进水
7.2 New words and expressions
Disinfection Chlorine Influent flow Ozone Oxidation Reduction Enzyme Catalyst Sulfide Benzene