Equipment purchase costs centrifugal

To a first approximation, the cost of a single MPI is assumed to vary with scale (vessel volume or process throughput) on an exponent of 0.7. The value of this exponent does vary from one plant item type to another and while it typically lies in the range 0.5-0.9 [40, 42] for some equipment types (e.g., centrifuges) it may be at or above unity. This indicates that the purchased cost of equipment per unit production rate, say /(tons per year), generally increases as manufacturing scale decreases well known as economies of scale, related to large bulk chemical plants. 

Purchase Costs of the Most Widely Used Process Equipment 517 Centrifugal backward-curved fan ... 

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