Chemical process industries: capital

Working capital may vaty from a very small fraction of the total capital cost to almost the whole of the invested capital, depending on the process and the industiy For example, in jewelry-store operations, the Fixed capital is veiy small in comparison with the working capital. On the other hand, in the chemical-process industries, the working capital is hkely to be in the region or 10 to 20 percent of the value of the fixed-capital investment. 

Overheads in the chemical-process industries are commonly calculated as a percentage of (I) direct materials cost, (2) direct labor cost, or (3) prime or direct costs. Other methods of allocating overheads are on the basis of (I) plant area, (2) number of employees, (3) capital value, and (4) elec tric power. 

Heat pumps are particularly suitable for recycling heat energy in the chemical-process industries. For the outlay of an additional fixed-capital expenditure Cec on a heat-pump system, a considerable reduction in the annual heating cost can be effected. 

The chemical process industries are competitive, and the information that is published on commercial processes is restricted. The articles on particular processes published in the technical literature and in textbooks invariably give only a superficial account of the chemistry and unit operations used. They lack the detailed information needed on reaction kinetics, process conditions, equipment parameters, and physical properties needed for process design. The information that can be found in the general literature is, however, useful in the early stages of a project, when searching for possible process routes. It is often sufficient for a flow-sheet of the process to be drawn up and a rough estimate of the capital and production costs made. 

The primary driver in sulfur recovery applications is not economic potential, but rather environmental regulation. The capital investment required for sulfur recovery facilities is significant. Increasing pressure to maximize recovery and throughput at minimum investment is constantly being brought to bear on the chemical process industry. 

Innovation is the key issue in today s chemical process industries. The main directions are sustainability and process intensification. Sustainability means in the first place the efficient use of raw materials and energy close to the theoretical yields. By process intensification the size of process plants is considerably reduced. The integration of several tasks in the same unit, as in reactive separations, can considerably simplify the flowsheet and decrease both capital and operation costs. 

Distillation is the baseline process for the chemical process industry, with 40,000 columns in operation in the US, handling 90-95% of all separations for product recovery and purification. The capital invested in distillation systems in the US alone is at least 8 billion [1]. 

Electrochemical reactor design is ideally a good compromise between capital and power costs. The power consumption of a cell or reactor is the most important single factor needed to evaluate its performance. Both the powar production and chemical process industries, (CPI), involve heat and electrical energy in a similar fundamental way, and so are governed by the second law of thermodynamics. The second law actually imposes an absolute natural limitation on the efficiency of any energy transformation, and therefore it provides a reliable standard with which to compare and control practical operations (30) (31) (32). 

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