化工过程设计讲义.doc

Robin Smith，Chemical Process Design， McGraw－Hill Book Co.世界图书出版公司，1995. Introduction of the Course （2学时） The steps of chemical process design: Select a series of processing steps (operation units) and connect them (little attention) Reactor Separator (distillation column, absorption, evaporator, dryer, adsorption, etc.) Heat exchanger Compressor Pump Etc. Analysis or simulation flosheet (more attention) During the synthesis of flowsheet, selection of operations is very importantmay seriously affect the capital cost, operation cost, safety, and environment. In this course, we will introduce the systematic design of reactor and separator with the emphasis on costs, safety and environment. 化工过程设计的层次 （The hierarchy of chemical process design） Introduction Synthesis of flowsheet Usually, we can’t transform raw material into desired products in one step. Generally, a chemical process is broken down into a number of steps, which are carried out through reaction, separation etc. Interconnection of individual steps to form the flowsheet Fig. 1.1a Synthesis of a chemical process including two steps: Selection of individual steps Interconnection of individual steps Simulation Fig. 1.1b Optimization Overall Process Design Is it simple to design a chemical process? Let’s take a simple example: transform feed or raw material into desired products. We can perform this transformation by reactor, as shown by Fig. 1.2(a). However, not all feed can be transformed into products, and there are some byproducts. Therefore, to get desired products with certain purity, we have to separate products from the unreacted feed and byproducts. To use raw material efficiently, the unreacted feed can be recycled to the reactor. Based on this, the whole flowsheet can be obtained. Consider the heat integration, now flowsheet can be designed and is better then the original one (Fig. 1.3). Retrofit the reactor (Fig. 1.4), and correspondingly retrofit the separation order. Again, heat integra