Answer Happy

GUIDETO QUESTION 1 (40 MARKS) There is no choice in Question 1. It consists of a set of short answer questions. Each question is worth between 2 and 8 marks, with questions being worth 4 marks on average. Tips for answering Question 1: - Some questions ask for more than one thing; e.g. What is meant by X ? Give an example of X∗. Please make sure you answer both parts. - If you are asked to list, name or state something. you just need to list/name/state the thing asked. If you are asked to exploin X number of things, you would not get full marks just for listing the things. Here are examples of the kinds of questions that may be asked: (a) Three general approaches to process synthesis have been discussed in this unit. Explain them briefly in one or two sentences each. (b) Three broad approaches to process synthesis have been discussed in this unit. Explain one of them and give a brief example of its use. (c) What is a "heuristic"? What is one advantage and one disadvantage of using them? (d) What are two reasons for using heuristics in chemical engineering? What is an example of a heuristic you have encountered in your studies? (e) For reversible reactions, explain how the choice of optimum operating temperature differs for exothermic reactions compared to endothermic reactions. (f) Sketch a reactor system that uses cold shots. Why would they be used? (g) In the version of the Attainable Region method presented in this unit, what input information is required? (h) Say you had the reactions A+B→P and P→U, where P is the desired product and U is an undesired by-product. What type of reactor would favour production of the product? (i) Name the two main approaches used for calculating the phase equilibrium constant, K, for non-ideal systems. (j) What is meant by the term "simple separator"? Give an example of one. (k) Say you need to separate a mixture into three products ((D,, and (3) by using simple distillation columns. Sketch a flowsheet that uses the Direct Sequence to separate them. Note any assumptions used. (I) Draw x−y diagrams for an azeotropic binary mixture and a non-azeotropic binary mixture. Briefly explain how the presence of an azeotrope influences the structure of the separator network. (m) Sketch a flowsheet that shows the use of an inert heat carrier in a process with a reactor and a separation system consisting of simple separators. Briefly state the assumptions you made in drawing the flowsheet.