Answer Happy

QUESTION 2 [50 marks] You have been awarded a contract to conduct some conceptual synthesis of a new process according to several scenarios of interest to your client. For all scenarios, please note: - Stream FEED1 contains reactant A and inert species I. Stream FEED2 stream contains pure reactant B. - Species C is an intermediate reaction species. Species D is the desired product and species E is a by-product that will be sent for further treatment. The further treatment is out of the scope of this question. - Two separate reactors are needed to conduct the following irreversible reactions: - Reactor R1: A+B→C - Reactor R2: C→D+E - Simple distillation columns are to be used for all separations. No azeotropes or solids are present. More and less volatile species need to be correctly allocated to the top and bottom streams from each column. The columns produce perfect separations. Label the columns $1, \$2, \$3, etc. - The order of species volatility from most to least volatile is A, B, I, D, E, C. - Separation processes can be conducted before R1 and R2, between then and after them, as appropriate. - The flowsheets should show reactors, separators and all streams, including recycle streams where appropriate. Label the species present in every stream. For each of the scenarios below, sketch the flowsheet and explain the conditions that would favour use of that flowsheet: (a) Scenario 1: no feed purification, incomplete conversion of all reactants in R1 and R2, direct column sequence, no use of purge streams. [12 marks] column sequence, no use of purge streams. [12 marks] (b) Scenario 2: feed purification, incomplete conversion of both reactants in R1, complete conversion in R2, direct column sequence, no use of purge streams. [10 marks] (c) Scenario 3: no feed purification, use of excess B in R1, incomplete conversion in R2, indirect column sequence, use of a purge stream to control the I concentration if appropriate. [12 marks] In addition, considering all your flowsheets, please answer the following: (d) What other equipment items would be needed to complete the process design? Write very brief notes about the main points. [8 marks] (e) How could you check that your synthesised process was feasible and realistic? [8 marks]