Capital reliability

Finally, analytical methods can be compared in terms of their need for equipment, the time required to complete an analysis, and the cost per sample. Methods relying on instrumentation are equipment-intensive and may require significant operator training. For example, the graphite furnace atomic absorption spectroscopic method for determining lead levels in water requires a significant capital investment in the instrument and an experienced operator to obtain reliable results. Other methods, such as titrimetry, require only simple equipment and reagents and can be learned quickly. 

The choice of a particular mass spectrometer to perform a given task must take into account the nature of the substances to be examined, the degree of separation required for mixtures, the types of ion source and inlet systems, and the types of mass analyzer. Once these individual requirements have been defined, it is much easier to discriminate among the large number of instruments that are commercially available. Once suitable mass spectrometers have been identified, the final choice is often a case of balancing capital and running costs, reliability, ease of routine use, after-sales service, and the reputation of the manufacturer. 

Improving the economics of gas plant design, construction, and operations is essential to ensure the approval of future de-bottlenecking, capacity expansion, and new projects. The economics include not only capital investment, life cycle operations, and maintenance costs, but also the monetary equivalents of safety, reliability, and availability. 

Type of Plant Capital Cost /kW Heat Rate Btu/kWh kJ/kWh Net Efficiency Variable Operation Maintenance ( /MWh) Fixed Operation Maintenance ( /MWh) Availability Reliability Time from Planning to Completion Months... 

A utility area superintendent once made the remark to me, Others have only one process unit to worry about, but in utilities, everybody s problem is my problem. Utilities have a way of being taken for granted until a problem develops. In the study phase of a project, it is well to attach great importance to utilities, making sure that this portion of the capital estimate is large enough to provide reliability and sufficient spare capacity. 

The guidelines are quite general, but will at least act as introduction to the types of turbines available to the process designer. Sometimes the decision on which type turbine to select is not obvious. The back pressure turbine is most frequently selected. It has lower capital cost, simple construction, is the most suitable turbine for high speeds, and is generally more reliable. 

In general, slower speed units will be larger, heavier, and more costly than higher speed units. Slower speed units have the advantages of higher reliability, greater fuel efficiency, and lower maintenance costs than higher speed machines. The overall economics of initial capital cost, reli-abilit, fuel cost, maintenance costs, etc., must be considered to determine the most appropriate version for a particular installation. 

Although turbocharging an engine increases the bhp for a nominal additional capital cost, it has the disadvantage of increasing maintenance costs and decreasing engine reliability. 

The choice of whether to purchase or generate electricity and decisions on generator or cable configuration and sparing are often not obvious. An economic study evaluating capital and operating costs and system reliability of several alternatives may be required. 

Even when the time comes to make a purchasing decision, an energy-efficient motor purchase is not a certainty. Sometimes an energy-efficient motor will be the economically efficient choice at other times, not. The capital investment decision is based on the cost in relation to performance, efficiency and reliability. Moreover, the decision depends on the application and the amount of time the motor is in operation. It can be the major component of a product (drill or mixer), or a minor component (computer disk drive) it can be the major component cost of a product (fan), or it can be a minor component cost (stereo tape deck) it can run almost constantly (fan, pump, and machinery), or only a few minutes a day (vacuums and power tools). For example, contractors purchase circular saws almost solely based on performance and reliability. Time is money, and since the saw is operating only a few minutes a day and the contractor is often not responsible for the electricity costs to run the motor, energy efficiency is not a consideration performance and reliability are what matter most. On the other hand, an industrial user, who runs huge electric motors twenty-four hours a day to work pumps, machinery, and ventilation equipment, is very concerned tvitli energy efficiency as well as performance and reliability. 

System integration involves numerous miscellaneous development activities, such as control software to address system start-up, shut-down and transient operation, and thermal sub-systems to accomplish heat recovei y, heat rejection and water recoveiy within the constraints of weight, size, capital and operating costs, reliability, and so on. Depending on the application, there will be additional key issues automotive applications, for example, demand robustness to vibrations, impact, and cold temperatures, since if the water freezes it will halt fuel cell operation. 

Where small and/or single contaminant effluents are encountered, packaged treatment plants may be acceptable. Consideration should, however, be given to capital cost, payback period, reliability of equipment, maintenance, plant-life expectancy and contaminant-removal efficiencies. 

Microfiltration and ultrafiltration have recently been introduced for the removal of particles down to any desired size. Their capital cost is relatively high. Experience with them is limited, and a short trial with a small-scale pilot element is advisable. Prediction of full-scale performance from such trials is normally quite reliable. 

The main consideration in the selection of a compressor plant is the production of an adequate supply of compressed air at the lowest cost consistent with reliable service. The installation of a compressed air system, as with all forms of power transmission, calls for capital investment with consequent operating and maintenance costs. The information on which the selection of plant is based should be as accurate as possible. Important factors to be considered are the following. 

What facility is there for evaluation (e.g. life-cycle costing, capital write-off/replacement, design, reliability) ... 

Repeat Problem 4.19 for C = 0.6 and 1.0. Note that more reactors will affect more than just the capital costs. Additional equipment will lower system reliability and increase operating costs. Which value of C is the more conservative Is this value of C also the more conservative when estimating the installed cost of an entire plant based on the cost of a smaller plant ... 

Conclusions concerning further process studies can be drawn from this simple analysis. (1) There is a need to try to reduce foaming at stage 2 of process A. If the requirement concerning the volume of vessel 2 in process A could be reduced by 40%, tank AE2500 with a capacity of 3.46 m might be sufficient, which would significantly decrease the capital costs. (2) Physical properties of all mixtures should be determined and thermokinetic data for the second steps of both processes provided to make calculations of the schedule more reliable. 

Capital cost estimates for chemical process plants are often based on an estimate of the purchase cost of the major equipment items required for the process, the other costs being estimated as factors of the equipment cost. The accuracy of this type of estimate will depend on what stage the design has reached at the time the estimate is made, and on the reliability of the data available on equipment costs. In the later stages of the project design, when detailed equipment specifications are available and firm quotations have been obtained, an accurate estimation of the capital cost of the project can be made. 

Many issues need to be considered when choosing the most appropriate combination of drivers. Choosing the best combination is a trade-off between capital costs, operating costs, system flexibility and reliability. 

Because of high capital costs and potential HE of steel pipelines for high-pressure hydrogen transport, the investigation of fiber reinforcement or other plastic composites as substitutes for steels is one of the major R D tasks within the DOE hydrogen delivery program. The purpose of the work is to achieve reduction in installation costs, better reliability, and safer operation of hydrogen pipelines. 

An inherently safe plant1112 relies on chemistry and physics to prevent accidents rather than on control systems, interlocks, redundancy, and special operating procedures to prevent accidents. Inherently safer plants are tolerant of errors and are often the most cost effective. A process that does not require complex safety interlocks and elaborate procedures is simpler, easier to operate, and more reliable. Smaller equipment, operated at less severe temperatures and pressures, has lower capital and operating costs. 

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