Capital minimisation

Generally, for most fermentation processes to yield a good quality product at a competitive price, at least six key criteria must be met. (/) Fermentation is a capital intensive business and investment must be minimised. (2) The raw materials should be as cheap as possible. (J) Only the highest yielding strains should be used. (4) Recovery and purification should be as rapid and as simple as possible. (5) Automation should be employed to minimise labor usage. (6) The process must be designed to minimise waste production and efftciendy use all utilities (26,27). 

The benefits of high selectivity He in the abiUty to produce high purity cobalt in a limited number of stages. This minimises capital and operating costs. It is particularly important when the solution in question contains low concentrations of cobalt. Eor example, solutions derived from laterite deposits may only contain 0.5—2 g/L Co but 90—100 g/L Ni. 

This quantity is minimised when the stage is operated at a pressure ratio across the barrier corresponding to r = 0.285. Furthermore, if power were the only economic consideration, the stage would be operated at this pressure ratio. However, as the value of ris decreased from this optimum, although the cost of power is increased, the number of stages required and hence the capital cost of the plant is decreased. Thus, ia practice a compromise between these factors is made. 

In the chemical industry processes are often capital intensive with consistent raw materials being converted into long-life products. If a process is capital intensive it pays to run the process 24 hours a day, 7 days a week, 52 weeks a year, as far as technically possible. Labour costs are likely to be minimised by working continuously as well. 

Capital cost was to be minimised by use of innovative but proven process design. 

It should be noted that the operating parameters of the unit can be adjusted to suit the client s needs. These particular operating conditions were an attempt to maximise productivity (i.e. minimise capital cost) and minimise the waste volume. While the NaCl recovery efficiency is about 96%, the brine purity is not exceptionally good (43.4% sulphate removal). This is not considered a disadvantage, however, since the low removal efficiency can be compensated for by increasing the flow of feed that is treated by the system. If necessary, removal efficiencies of over 95 % can be obtained. 

Ultimately, the decision should reflect the criticality of the step on product quality. Thus although capital expenditure may appear undesirable, minimising process changes also reduces the risk of unanticipated differences in process performance, product quality and could facilitate regulatory approval at a later stage. 

Explanations and details of these terms can be obtained in various books and pamphlets, for instance, Allen (1980) and Liversey (1983). No one parameter is self-sufficient, and alone gives a complete view of the financial status of a project or product. Therefore a number of parameters are usually calculated, and used in conjunction. They serve to give indications of how to minimise the period over which capital needs to be committed to a specific project, to show changes in the cost-structure of the process with time, and to reduce the time taken to convert the material, labour and overhead resources (the working capital) into cash in the form of profits from sales. That is, to make the cash-flow as favourable as possible. Each comparer will have different criteria as to what constitutes an acceptable financial risk when evaluating a project. Obviously healthcare product/pharmaceutical companies have quite different criteria to companies manufacturing bulk chemicals. 

The minimisation of capital has exercised the minds of every generation of engineers, so what is new today. In spite of several years of low and relatively predictable inflation and interest rates the financial markets expectation is often for double figure growth at minimum capital investment. The hapless Chemical Company finance director seeking several hundreds of millions of pounds over 20 years is unlikely to excite the market. 

The above heuristics may produce a feasible but not always optimum sequence. In principle, the sequences can be compared by means of operation and capital costs. The first depends on the total utility consumption, proportional with the vapour rate. The second depends on the number of stages. Glinos Malone (1988) demonstrated that optimal sequencing depends less on the total number of stages, but near-optimum sequences are those minimising the total vapour rate of key components. Therefore, when the relative volatility of keys differs considerably the estimation of total vapour flow based only on partial feeds is in large error. It is worth to mention that the method described before can be used for ranking of sequences, but not to determine the effective optimal vapour flow. 

Figure 10.19 Targeting of by minimisation of capital and utility costs...

These are also optimisation variables. The number of stages can be put equal to the temperature intervals. Finding the number of matches is similar with the extended transhipment model. However, the constraint of the Pinch can be removed easier, and by consequence, leading to networks that minimise simultaneously units, capital and energy. Other structural features, as steam splitting and bypassing, can be considered. 

From steady state point of view, the size of equipment should be kept as small as possible in order to minimise the capital cost and prevent safety risks. However, a too small volume increases the sensitivity to disturbances, and in the worst case can upset the operation. Therefore, the design should provide sufficient capacity to dump fluctuations, although an excessive value would give too long transients. Hence, the design of capacities is a matter of optimisation, both from steady state and dynamic viewpoint. 

Thus, one area in which organic farmers encounter problems in the production of crops and livestock is in the maintenance of soil fertihty and avoidance of pest attacks, while minimising the environmental effects of their actions. The exact nature of the soil, pest and enviromnental issues is geographically determined. For example, in a climate where frequent small amounts of rainfall occur, weeds are more likely to be a problem, while warm and humid conditions are more conducive to fungi or pest problems in crops and livestock. Dealing with these may require a change in use of other inputs, such as labour and capital. 

Capital creators for each industry combine inputs to form units of capital. In choosing these inputs, they cost minimise subject to technologies similar to that used for current production the only difference being that they do not use primary factors. The use of primary factors in capital creation is recognised through inputs of the construction commodity. 

As moulds have a high capital cost, injection moulding is usually economic, only if more than 10000 products are made. It is preferable to reduce the cycle time than to invest in a second mould to achieve the required production rate. The mould only has a high productivity if the cooling time, which dominates the cycle time, is minimised. Consequently, the product wall thickness is minimised (Eq. 5.4 predicts the effect on the cooling time). Sections 3 and 4 of Chapter 13 consider further suitable product shapes for injection moulding. 

Batch production can therefore be useful for small businesses who wish to minimise the initial investments and working capital required for the continuous production lines. The producer can cease production any time without having to keep the plant running (which can result in losses). 

They shall make small changes to or provide additional features to existing machinery to obtain required performance with small incremental investment at a time. This can minimise additional capital required and can make maximum use of existing units. In certain cases, this approach will not work, and it will be necessary to make major changes even to start the plant (e.g. changing the complete reactor itself). 

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