抄録
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.
