Lesson 4 Chemical Reaction Engineering
化学反应工程
A1 Every industrial chemical process is designed to produce economically a desired product from a variety of starting materials through a succession of treatment steps.
每一个工业化学过程的目的是从不同的原材料，经过一系列的处理步骤生产经济所需的产品。
2 Fig. 4-1 shows a typical situation.
图 4-1展示了一个典型的情况。
3 The raw materials undergo a number of physical treatment steps to put them in the form in which they can be reacted chemically.
鳄鱼肉怎么做原料进行了一些物理处理的步骤，使它们能够发生化学反应。
4 They then pass through the reactor.
然后让他们通过反应器。
5 The products of the reaction must then undergo further physical treatment- -parations, purifications, etc. - for the final desired product to be obtained.
产物要经历进一步的物理处理——分离，净化提纯等等，以获得期望的最终产品。
B1 Design of equipment for the physical treatment steps is studied in the unit operations.
物理处理步骤设备的设计在单元操作中研究。
2 Here we are concerned with the chemical treatment step of a process.
在这里我们关心的是一个过程的化学处理步骤。
3 Economically this may be in inconquential unit, say a simple mixing tank .
从经济的角度说，这可能是个不重要的单元，比如说一个简单的搅拌槽。
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4 More often than not, however, the chemical treatment step is the heart of the process, the thing that makes or breaks the process economical.
然而通常，化学处理步骤是一个过程的核心，它决定这个过程经济的成败。
C1 Design of the reactor is no routine matter, and many alternatives can be propod for a process .
反应器的设计不是普通的事，对于一个过程有许多可供选择的建议。
2 In arching for the optimum it is not just the cost of reactor that must be minimized.
寻找最佳的条件，不仅是反应器成本的最小化。
3 One design may have low reactor cost, but the materials leaving the unit may be such that their treatment requires much higher cost than alternative designs.
一个设计可能反应器的成本较低，但材料离开装置可能比其他的设计需要更高的处理费。
4 Hence, the economics of the over-all process must be considered.
因此，必须要考虑整个过程的经济。
D1 Reactor design us information, knowledge, and experience from a variety of areas thermodynamics, chemical kinetics, fluid mechanics, heat transfer, mass transfer, and economic.
反应器的设计使用了各个领域的信息，知识和经验，比如热力学，化学动力学，流体力学，传热，传质，和经济学。
2 Chemical reaction engineering is, the synthesis of all the factors with the aim of properly designing a chemical reactor.
化学反应工程，是这些因素的综合学科，旨在设计出正确的化学反应器。
E1 The design of chemical reactors is probably the one activity which is unique to chemical engineering, and it is probably this function more than anything el which justifies the existence of chemical engineering as a distinct branch of engineering.
化学反应器的设计对于化学工程而言可能是一个独特的活动，它的这个功能可能比任何东西都更能证明化学工程作为一个独特的分支工程的存在。
F1 In chemical reactor design there are two questions which must be answered:
(i) What change can we expect to occur？ (ii)How fast will they take place？
化学反应器的设计有两个必须回答的问题：
（1）我们预期发生什么变化？（2）他们发生的有多快？
2 The first question concerns thermodynamics, the cond the various rate process- -chemical kinetics, heat transfer, etc.
第一个问题涉及热力学，第二个问题涉及各种速率过程——化学动力学，传热等。
3 Putting the all together and trying to determine how the process are interrelated can be an extremely difficult problem; hence we start with the simplest of situations and build up our analysis by considering additional factors until we arc able to handle the mor
e difficult problems.
把这些放在一起，试图确定这些过程是怎样相关联的， 是一个非常困难的问题；因此，我们从最简单的情况着手，考虑附加因素，建立我们的分析，直到我们能处理更难的问题。
G Thermodynamics 热力学
1 Thermodynamics gives two important pieces of information needed in design, the heat liberated or absorbed during reaction and the maximum possible extent of reaction.
热力学给出设计中需要的两条重要的信息，在反应中会放出和吸收热量，而且最大值可能表示反应的程度。
2 Chemical reactions are invariably accompanied by the liberation or absorption of heat, the magnitude of which must be known for proper design. Consider the reaction
马桶堵住了怎么办aA→rR+sS ,ΔHr
涂鸦移动
positive, endothermic ; negative , exothermic
化学反应总是伴随着热量的释放或吸收，为了合理的设计，必须知道它的大小，考虑下面的反应：aA→rR+sS ,ΔHr ,正反应，吸热；逆反应，放热。
H1 The heat of reaction at temperature T is the heat transferred from surroundings to the reacting system when a moles of A disappear to formqq密码泄露 r moles of R and 赞美祖国大好河山的诗句s悠悠球大赛 moles of S, with the system measured at the same temperature and pressure before and after reaction.
温度为T时， a mol的A消失生成了r mol的R和s mol的S，反应的热量是环境传递给反应体系的，这是在反应前后相同的温度和压力下对体系测量的结果。
2 With heats of reaction known or estimable from thermochemical data, the magnitude of the heat effects during reaction can be calculated.
