Boilers costing analysis

The cost estimate should include provisions for any required satellite boiler water analysis laboratories. The central control lab cannot normally handle analyses of widely spread boilers satisfactorily. The designers, while remembering satellite water laboratory facilities for the utilities area, might overlook similar facilities for the steam generation in the process area. 

The column shell plus auxiliary pumps, heat exchangers, boilers, and reflux drum cost anywhere from three to six times as much as the trays or packing in a typical installation that is outdoors and operating under pressure or vacuum. Specific cases can vary by orders of magnitude Sawistowski and Smittf present a cost analysis for a column where the shell plus auxiliary equipment costs less than the plates. 

Hartford Steam Boiler Inspection and Insurance Company (HSB) insures distribution transformers for power generation utility companies. The cost to HSB when an insured transformer fails often exceeds a million dollars. The possibility of losses of this magnitude has given HSB the incentive to develop a transformer fault early detection and diagnosis program, based on chemical analysis of the transformer insulating oil. 

For purposes of comparison, a fossil-fueled boiler producing by-product power was also included in the analysis. As shown in Figure 7, such a plant could be built today to produce fresh water at an estimated cost of about 35 cents a thousand gallons, assuming that the power plant would be base-loaded the same as the water plant. However,... 

Regional economics of TDF are paramount. Electric Power Research Institute (EFRI) created a computer model of TDF use in a cyclone-fired boiler. The model included an economic analysis of alternative fuel firings to account for the fact that, if boiler efficiency decreases, the company would need to purchase power to replace power lost by the boiler derating.12 These costs are called "busbar power costs".12 Even considering the decrease in the net heat rate caused by TDF use, the model found that TDF provided overall savings in levelized busbar power costs relative to 100 percent coal-firing.12... 

Boiler Feedpump Drives. Second-Law techniques are applied to a practical problem determing when to drive feedpumps with electric motors and when to use steam turbines. This analysis was performed by Fehring and Gaggioli (40) for the Wisconsin Electric Power company. The Second-Law costing procedures are straightforward, avoiding the extremely laborious calculations associated with traditional methods, and/or avoiding the erroneous conclusions often drawn when those methods are simplified. 

Study of the power-input curves shows that the hydraulic and electric couplings have the smallest power input. Their first cost, however, is usually greater than any other types of power-saving devices. To determine the return on any extra investment in power-saving devices, an economic study, including a load-duration analysis of the boiler load, must be made. 

In making a decision on which particle sizing technique to us, the analyst must consider the purpose of the analysis. What is generally required is not the size of the particles, but the value of some property that is size dependent. In such circumstances it is important whenever possible to measure the size dependent property, rather than to measure the size by some other method and then deduce the required property. For example, in determining the size of boiler (fly) ash with a view to predicting atmospheric pollution the terminal velocities of the particles should be measured in measuring the size of catalyst particles, the surface area should be measured, since this is the property that determines the reactivity. The cost of the equipment as well as the ease and the speed with which the analysis can be carried out have then to be considered. The final criteria are that the method shall measure the appropriate property of the particles, with accuracy sufficient for the particular application at an acceptable cost, in a time that will allow the result to be used. 

In illustrating the role played by available energy analysis in design optimization, one of two methods was demonstrated. The boiler problem used available energy balances to obtain all the pertinent consumptions and transports of available energy. This method reveals the relative importance of consumptions and losses with respect to the other transports of available energy into, out of, and within the system. It also provides a consistent basis for accurate costing of flow streams. 

The economic analysis to follow depends upon the evaluation of the various available-energy supplies for feedwater heating and, in turn, the costs associated with those supplies. In particular, the costs of interest, for each case, are those required to take the feedwater from the conditions at the inlet to heater number 4 to the normal temperature of feedwater entering the boiler. These costs include the cost of bleeder steam, which is used to increase the temperature of feedwater in the heater and, under the conditions of Case C, the cost of the additional boiler fuel required when the heater is out of service and the temperature of the feedwater is below normal. The hourly cost of feedwater heating for Cases A and B is given by... 

The important aspect related decision in decommissioning phase is the Optimum Replace time assessment that defines when each equipment item must be replaced due to the increase operational cost. Regarding this analysis, the boilers must be replaced at 2.34 years because despite not cause impact on system operational availability due to standby configuration the operational cost increase on time as shows the Figure 12. 

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