Equipment cost example

Phase separation is controlled by phase equilibrium relations or rate-based mass and heat transfer mechanisms. Chemical reactions are controlled by chemical equilibrium relations or by reaction kinetics. For reactive distillation to have practical applications, both these operations must have favorable rates at the column conditions of temperature and pressure. If, for instance, the chemical reaction is irreversible, it may be advantageous to carry out the reaction and the separation of products in two distinct operations a reactor followed by a distillation column. Situations in which reactive distillation is feasible can result in savings in energy and equipment cost. Examples of such processes include the separation of close-boilers, shifting of equilibrium reactions toward higher yields, and removal of impurities by reactive absorption or stripping. 

As an example of this technique, the estimated equipment costs for a large coal gasification project have been correlated and programmed for a computer. Thus, it is vei7 easy to get the cost of any one piece, or of many pieces of equipment, for a coal gasification or hydrocarbon processing project once the specification sheets are completed. 

For instance, in the aforementioned heat exchanger example, the FOB equipment cost was 40,100. If this exchanger is to operate in an oil refinery (primarily a fluid processing plant), the fixed capital investment is 4.83 x 40,100 - 193,700. 

Example 7.4-3. Minimiz.ation of equipment cost.s for a single-product plant (after Loonkar and Robinson, 1970)... 

The objective function, Eqn. 7.4-31, will be minimized subject to the horizon constraints of Eqn. (7.4-54) and other conventional constraints, imposed by limits on equipment sizes, etc. Example 7.4-6 illustrates the use of the above model for the minimization of equipment costs in the design of a batch plant. 

The cost of specialised equipment, which cannot be found in the literature, can usually be estimated from the cost of the components that make up the equipment. For example, a reactor design is usually unique for a particular process but the design can be broken down into standard components (vessels, heat-exchange surfaces, spargers, agitators) the cost of which can be found in the literature and used to build up an estimate of the reactor cost. 

TES-based systems are usually economically justifiable when the annualized capital and operating costs are less than those for primary generating equipment supplying the same service loads and periods. TES is often installed to reduce initial costs of other plant components and operating costs. Lower initial equipment costs are usually obtained when large durations occur between periods of energy demand. Secondary capital costs may also be lower for TES-based systems. For example, the electrical service equipment size can sometimes be reduced when energy demand is lowered. 

It should be emphasized that capital cost estimates using installation factors are at best crude and at worst highly misleading. When preparing such an estimate, the designer spends most of the time on the equipment costs, which represents typically 20 to 40% of the total installed cost. The bulk costs (civil engineering, labor, etc.) are factored costs that lack definition. At best, this type of estimate can be expected to be accurate to 30%. To obtain greater accuracy requires detailed examination of all aspects of the investment. Thus, for example, to estimate the erection cost... 

Charts, correlations, and tables in the sources cited earlier relate capital costs to various parameters characteristic of the equipment to be evaluated. Table B.2 lists typical parameters used to correlate equipment costs for common types of process equipment. Figure B.3 is an example of such correlations for the cost of heat exchangers as a function of exchanger area. These forms of cost curves generally appear as nearly straight lines on log-log plots, indicating a power-law relationship between capital cost and capacity, with exponents typically ranging from 0.5 to 0.8. 

Example 5 Fixed Capital Investment Using the Lang, Hand, and Wroth Methods The following is a list of the purchased equipment costs for a proposed processing unit ... 

The major drawback of this reaction system is the high energy and equipment costs due to the use of high pressures. In addition, the use of supercritical carbon dioxide can have adverse effects on enzymes, for example, by decreasing the pH of the microenvironment of the enzyme, by the formation of carbamates owing to covalent modification of free amino groups at the surface of the protein and by deactivation during pressurisation-depressurisation cycles [4]. 

No one curing process posesses all the virtues and those which may appear to be most desirable may be rejected on grounds of initial cost and maintenance of the equipment. For example even an autoclave curable rubber lined vessel can be cured in open steam at atmospheric pressure and this method can be adopted while the autoclave is down for repairs and maintenance. 

Table 3.15 summarizes the advantages and disadvantages of various extraction techniques used in the analysis of semivolatile organic analytes in solid samples. They are compared on the basis of matrix effect, equipment cost, solvent use, extraction time, sample size, automation/unattended operation, selectivity, sample throughput, applicability, filtration requirement, and the need for evaporation/concentration. The examples that follow show the differences among these techniques in real-world applications. 

Since the first multilayer ceramic capacitor (MLCC) was introduced in the early part of World War II there have been two principal development trends. One is towards smaller sizes and higher capacitance values, that is towards maximizing volumetric efficiency, and the other is cost reduction. These developments have had to be accompanied by improved reliability, which assumes increasing relevance as the number of capacitors in a given piece of equipment, for example a PC or mobile phone, steadily increases. 

High- and medium-value products such as pharmaceuticals and foods are manufactured within a regulated environment which imposes various legislation and guidelines on manufacturers. These regulatory constraints will also influence the choice of bioseparation equipment. For example, to maintain appropriate levels of cleanliness or sterility for certain products requires specialized equipment at a premium cost. 

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