การออกแบบโรงงานทางวิศวกรรมเคมี ( Chemical Engineering Plant Design)

1. การออกแบบโรงงานทางวิศวกรรมเคมีการออกแบบโรงงานทางวิศวกรรมเคมี (Chemical Engineering Plant Design)

2. Design • 1. Conceptual design: develop a preliminary flowsheet using approximate methods. • 2. Preliminary design: use rigorous simulators to evaluate steady-state and dynamic performance of proposed flowsheet. • 3. Detailed design: specify type of trays, no. of sieve tray holes, piping, pumps etc. 2

3. CHAPTER 1 THE NATURE OF PROCESS SYNTHESIS AND ANALYSIS

4. 1.1 Creative Aspects of Process Design The propose of engineeringis to create new material wealth. Process and plant designis the creative activity whereby generate idea and then translate them into equipment and processes for producing new materials or for significantly upgrading the value of existing materials.

5. In any particular company, we might try to generate new idea: • To produce a purchased raw material • To convert a waste by-product to a valuable product • To create a completely new material (synthetic fibers, food, bioprocessing) • To find a new way of producing an existing product (a new catalyst, a bioprocessing alternative) • To exploit a new technology (genetic engineering, expert systems) • To exploit a new material of construction (high-T or high-P-operation, specialty polymer)

6. Level of Engineering Designs Frome A. Pikulik and H.E. Diaz, “Cost Estimating Major Process Equipment,” Chem. Eng., 84(21): 106(1977)

7. TABLE 1.1-2 Engineering Costs to Prepare estimates(1977) Frome A. Pikulik and H.E. Diaz, “Cost Estimating Major Process Equipment,” Chem. Eng., 84(21): 106(1977)

8. 1.2 A Hierarchical approach to Conceptual Design Example Hydrodealkylation of Toluene

9. HDA Process Basic information: 1. Reactions take place between 1150-1300 F. 2. Pressure is about 500 psi. 3. Excess hydrogen (5/1 ratio) prevents coking. 4. Effluent gas must be quenched to 1150 F in order to prevent coking.

10. HDA Process

11. HDA Process 11

12. HAD Process 12

13. Vapor Recovery System As a vapor recovery system we could use one of these • Condensation(high P or low T, or both) • Absorption • Adsorption • A membrane process

14. Simplified Flowsheet for the Separation Systems 14

15. Recycle Structure of the Flowsheet 15

16. Input-Output Structure of the Flowsheet 16

17. Possible Limitation Hierarchy of decisions______________ 1. Batch versus continuous 2. Input-output structure of the flowsheet 3. Recycle structure of the flowsheet 4. General structure of the separation system a. vapor recovery system b. liquid recovery system 5. Heat-exchanger network______________ The goal 0f conceptual design is to find the “best” alternative 17

18. Shortcut Solutions Decomposition Procedures for Existing Processes • Remove all the heat exchangers, drums, and storage vessels. • Group all the distillation columns (liquid separation system block) • Simplify the general structure of the separation system (similar to fig. 1.2-5) • Lump (group all units in single box) the complete separation system (similar to fig. 1.2-6) • Lump the complete process. 18

19. IPA Plant 19

20. Ethybenzene Process 20