Page 63 - Plant design and economics for chemical engineers

46 PLANT DESIGN AND ECONOMICS FOR CHEMICAL ENGINEERS

(d) The caustic treated thiophane is then batch distilled in a packed tower and sent
to storage before eventual shipment to commerical use.
(e) Recoverable THF is recycled back to the reactors from the batch column.
(fl The aqueous bottoms stream is stored for further processing in the plant.
(g) Carbon deposition on the catalyst is heavy (4 percent of THF feed) and
therefore provision for regeneration of the catalyst must be made.
Assist the consultant in analyzing this process with a complete flow sheet and
material balance, assuming 85 percent operating factor, 80 percent conversion in
the reactor, and 90 percent recovery after the reactor. Outline the types of
equipment necessary for the process. Determine approximate duties of heat
exchangers and list overall heat balances on the plant. It is known that the heat
of formation of THF is -59.4 kcal/g mol, H,S is -4.77 kcal/g mol, and
thiophane is - 17.1 kcal/g mol.
What additional information would be required in order to complete the
project analysis?
Physical properties:
THF MW=72 sp gr = 0.887 Boiling pt. = 65°C
Vap. press. at 25°C = 176 mm Hg
Thiophane, MW = 88 Boiling pt. = 121°C