Compressors purchase cost

The air compressor purchase cost was estimated on the basis of power consumption. The oxidation vessel and reactor costs were estimated using correlations appropriate for pressure vessels. Capacity formed the basis of the storage tank purchasing cost. The absorption and stripping column were costed according to diameter, operating pressure and number of trays. 

The base compressor purchase cost curves in Figure 16.9, for a CE cost index of 394, are given by the following equations, with Pc in horsepower ... 

Installation costs for the various units are estimated using the data of Ref. CE9 (Table 6 p.169). This data expresses typical installation costs for each unit as a percentage of purchase price. Compressors are rated at 30% of purchase cost heat exchangers at 35% towers/, columns at 60% metal tanks at 30%. Those items not included are estimated as having an installation cost at 30% of the purchase cost. 

The first stage of compression uses an axial compressor with steam turbine drive. It has a capacity of 511 m3/min (36 000 kg/h). Using Ref. CE9 (Figure 13.47, p.560), the estimated cost is US 300 000. This figure relates to 1979, when updated to 1986 costs and adjusted for currency differences the final Australian purchase cost is As490 000. 

The economic size for a pipe is the size with the lowest sum of annual charges for thle purchased cost of the pipe and pump and the annual power cost of running the pump or compressor needed to overcome friction. For turbulent flow, this results in an economic velocity which is practically independent jof everything but fluid density it is about 6ft/s for most liquids and about 40ft/s for air under normal conditions. 

Turton et al (2009) provide the following correlation [Equation (10.B.4)] for estimating the purchase cost of equipment (PCE) for a compressor and its drive. 

For the ammonia process, which operates at high pressure (200 atm), mostly in the gas phase, the total f.o.b. purchase cost of the on-site process equipment is 31,520,000. Installation costs boost this amount by a factor of 3.453 to a total bare-module cost of 108,830,000. As seen in Table 16.14, this cost is dominated by the gas compressors, with significant contributions from the heat exchangers and the membrane separators. Surprisingly, the reactor cost is a small fraction of the total cost. This is often the case for chemical plants. The reactor may not cost much, but it is the heart of the process and it better produce the desired results. 

Base f.o.b. purchase costs, Q, for the three major types of compressors, based on data from Garrett (1989) and Walas (1988) in Table 16.19, are plotted in Figure 16.9 as a function of consumed power, Pq, in horsepower for a cost index in mid-2000 (CE = 394). The base cost, which includes an electric motor drive, is for cast iron or carbon-steel construction. For other drives and materials of construction, the f.o.b. purchase cost is given by ... 

Figure 16.9 Base f.o.b. purchase costs for centrifugal, reciprocating, and screw compressors.

Table 16.32 Purchase Costs (f.o.b.) of Other Chemical Processing Equipment, CE Index = 394. Equations for pumps, compressors, motors, heat exchangers, and pressure vessels are in Section 16.5 ... 

These two vacuum systems can be compared on an annualized basis as discussed in Section 17.4, but it seems clear that the higher cost of the liquid-ring pump is more than offset by the much higher utility cost to operate the ejector system. The screw compressor is also a candidate, but its purchase cost, 65,000, is significantly higher and the annual electricity cost, at an overall efficiency of 70%, is only about 1,700/yr less than for the liquid-ring pump. ... 

Part Three includes chapters that provide instruction and examples of the design of heat exchangers, multistage and packed towers, and pumps, compressors, and expanders. In addition, Chapter 16 provides guidelines for selecting processing equipment and equations for estimating the purchase costs of a broad array of equipment items. Furthermore, Section 16.7 shows how to use the Aspen Icarus Process Evaluator (IPE), with the process simulators, to estimate purchase costs and the total permanent investment for a chemical plant. 

Note Compressors are high-speed rotating devices where the loss of material strength and thermal expansion is critical. It would be expected that the purchase cost of the conpressor would undergo a quantum junp for high-temperature operations. 

Figure A.1 Purchased Costs for Compressors and Drives (Cost Data for Compressors and Drives Taken from R-Books Software by Richardson Engineering Services, Inc. [4])...

Standard turboexpander-compressor sets designed and manufactured by competent manufactureres embody many of the reliability improvement and maintenance cost reduction features inherent in API (American Petroleum Institute) standards for other turbomachines. To achieve close compliance, however, the owner/purchasers must know their specific needs or requirements. Nevertheless, it may not be practical, feasible, or economically justified to achieve full compliance with API specifications, which were generally devised without giving thought to the peculiarities of turboexpanders and their sometimes differing operating environments. 

Supplier partnerships or alliances have been used to control the cost of procurement. They are based on methods developed in Japan, initially in the automobile industry. These methods have been extended into the process industry and for the purchase of such items as compressor trains. Generally as originally conceived, they were intended mainly for commodity items. By using some innovative approaches, the concept of partnerships or alliances has been extended into the purchase of custom equipment. 

Any resemblance to the first package cost and any later spare costs, unfortunately, is a coincidence. It is suggested, if funds permit, that at least the first spares be purchased with the compressor because they can be expected to come at a good price. 

Presuming that the information quoted by the vendors is accurate, then scrubber system A is effectively consuming over 30 times the "power" that system B consumes to do the same job The results, presented in Table II, show clearly that the 55.1 kPa (8 psi) pressure drop reduces all other consumptions of available energy to insignificance. If additional compressor capacity must be purchased to cover this power drain, the added capital cost would be roughly... 

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