14Design 1 Choice of Process Type (revised).pdf

DESIGN METHODOLOGY:
CHOICE OF PROCESS TYPE
GOAL -- Choose the process type appropriate
to the plant to be designed
1/31/99 Choice of Process Type 1
MAJOR PROCESS TYPES
uCONTINUOUS STEADY-STATE
ð Used for world-scale production modity chemicals
ð Large, centrally located plants
uBATCH
ð Used for small-scale production of high value-added chemicals
uJIT MINIPLANT
ð Used for on-site production of hazardous or difficult to transport
chemicals
Continuous Steady-State is the dominant process type.
1/31/99 Choice of Process Type 2
CONTINUOUS STEADY-STATE
(Continuous Steady State)
uWHEN USED
ð Large scale production (50 - 1000 MM Kg/yr)
ð Mostly for vapor/liquid processes
uADVANTAGES
ð Low cost of production through economy of scale
ð Allows on-site support infrastructure
uDISADVANTAGES
ð Large plant s often located in environmentally sensitive areas
ð Require storage and transportation of hazardous chemicals
ð Large on-site inventories of hazardous materials
ð Emissions control a problem
1/31/99 Choice of Process Type 3
BATCH
uWHEN USED
ð Small scale production (1 - 10,000,000 Kg/yr)
ð Fouling materials
ð Recipe driven process technology
uADVANTAGES
ð Flexibility of operation
ð Multiple product slates
ð Maintenance of sterile conditions for bioprocessing
uDISADVANTAGES
ð Labor in