Capital investment decisions design

Sp ecial cases of capital investment decisions include lease or buy decisions, when-to-replace decisions, which design to choose, and comparison of alternatives with unequal service lives. These special cases are covered in Park (1997) and in Ruegg and Marshall (1990), as are the other methods for capital investment decisions. 

The principal considerations involved in design of a process-scale chromatographic purification include scalability, reproducibility, safety, and validatability. Cost factors, however, must by necessity enter into all industrial decisions. Due to the high value-added nature of most biopharmaceuticals, this cost factor is driven by throughput, rather than by capital investment cost. 

Therefore, in connection with flow control system design, the first decision is whether control valves or variable-speed pumps should be used. In case of the second, flow is reduced by reducing the speed, and therefore, instead of the valve burning up the unnecessarily introduced pump head, that energy is not introduced in the first place. This reduces the operating cost of the process, but increases the capital investment, because the cost difference between variable and constant-speed pumps is usually more than the cost of control valves. 

Please prepare a preliminary design for the proposed plant. This design will be surveyed by the Process Development Division and used as a basis for further decisions on the proposed plant. Make your report as complete as possible, including a detailed description of your recommended process, specifications and cost estimates for the different pieces of equipment, total capital investment, and estimated return on the investment assuming we can sell all our product at the prevailing market price. We shall also be interested in receiving an outline of the type and amount of labor required, the operating procedure, and analytical procedures necessary. 

FMS is a capital investment-intensive and complex system. For the best economic benefits, an FMS should be carefully designed. The design decisions to be made regarding FMS implementation cover... 

In the same manner economical data from the life-cycle chain of a product application or process evaluation may also be calculated and summarized. In the end, this analysis can lead to better decisions with regard to product design, material utilization and capital investment. The rationale behind this assessment tool has been described by Saling et al. and by Landsiedel and Saling. " ... 

In addition to these evaluations on efficiencies and other design data, it is of course decisive to take capital investments into consideration. 

This simple process provides a convincing example of the need for simultaneous design. Had the decision of which alternative to build been made on just the steady-state economics of capital investment, the process would have been much more difficult to control, show larger swings in temperature and produce product of poorer quality. 

Selection of compression ratio is a major design decision and requires optimization of capital cost and energy consumption. The proper selection requires knowledge of energy costs and required return on investment. The decision will also be influenced by feed characteristics, material of construction, type of evaporator, hours of operation per year, turndown required, and type of drive. 

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