ANALYSIS OF PROCESS SYSTEM EFFICIENCY

Abstract

First, the relation between installation of storage and propagation of subsystem failure through the system is discussed in connection with cost. Criterion formula is derived.
Example : NH₃ and urea plant
Efficiency ; NH₃ 98% CO₂ 99% Urea 96%. Then instantaneous capacity of NH₃ and
Urea plant shall be +2% and +5% over average capacity, provided that storage
for NH₃ only is installed and not for CO₂. This result is actual design practice.
Another theme is active parallel redundancy, which is thought to be favorable for system
efficiency improvement.
Basic criterion for the above is
∫p¹(τ)dτ ?? 2∫p²(τ)dτ
where P¹ and P² are production function for a single stream and one stream of a two-stream system, respectively. Some factors and conditions for estimation of this production function are discussed.