Page 89 - Design of Simple and Robust Process Plants

74 Chapter 4 Process Synthesis and Design Optimization
± Apply process simplification
± Select reactor configuration and raw materials
± Select reactor conversion and selectivity
. Separation
± Collect physical, chemical, hazardous/toxicity properties, and equilibrium
data for relevant phase separations, of all involved components
± Develop an input and output process stream diagram, and identify all input
and output impurities by thoroughly detailed analysis of the reactor's inlet
and outlet, as well as any degradation product of additives as inhibitors
± Evaluate potential separations
± Select separations
± Apply process simplification
± Evaluate sequence of separations and select two to three flowsheets for inte-
gration studies
. Process integration
± Evaluate major options for integration within defined constraints (see next
paragraph)
± Apply exergy and pinch analysis technique to minimize targets for utility con-
sumption and integration opportunities
± Evaluate preliminary site integration alternative
± Apply process simplification
. Controllability analysis ± static
± Steady-state analysis for controllability and resilience (C&R) for flowsheet
alternatives
. Controllability analysis ± dynamic
± Determine dynamic C&R analysis
. Process flowsheet optimization
± Select the best flowsheet for optimization
± Divide process in sections and determine intermediate values and incremen-
tal values for recycle streams
± Optimize section by section
± Optimize overall flowsheet
. Logistics and site integration
The process synthesis methodology has been completed with two business decision
points, see Table 4.1. It is important to include these activities in the development
process as they have updated design input and ultimately require recent economics
next to there business input to support a stop or go decision.
The approach for a process synthesis methodology practical for industry is sum-
marized as:

. Selection of a starting point of the synthesis being the evaluation of existing
process technology resulting in a preliminary selected feasible flowsheet.
. Development of a hierarchical structural (layered) methodology based on the
interactive onion model.