Installed cost heat exchanger

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 remaining elements of are satisfied by installing new heat exchangers and are considered in the investment cost... 

The heat exchangers to be used are single tube and shell pass. The installed capital cost is given... 

Exponential cost correlations have been developed for individual items of equipment. Care must be taken in determining whether the cost of the eqmpment has been expressed as free on Board (FOB), delivered (DEL), or installed (INST), as this is not always clearly stated. In many cases the cost must be correlated in terms of parameters related to capacity such as surface area for heat exchangers or power for grinding equipment. There are four main sources of error in such cost correlations ... 

For air-cooled heat exchangers, recirculation is more difficult to define or relate to standard practices. Banks of air-coolers are installed in a variety of configurations so, for a particular proposed installation, a study by specialists may be required. This study of recirculation would probably be done later in the projeet even though the results impact costs. There is a practical limit to the number of front-end studies and this is one that can be deferred until geometry is better defined. 

These anodes, like platinised Ti may be supplied in different forms e.g. rod, tube, mesh, wire, etc. They may be used for the cathodic protection of offshore structures, heat exchangers, or even pipelines as they can be installed in the soil surrounded by carbonaceous backfill, and are comparable in cost to platinised titanium. ... 

Example 2.1 A new heat exchanger is to be installed as part of a large project. Preliminary sizing of the heat exchanger has estimated its heat transfer area to be 500 m2. Its material of construction is low-grade stainless steel, and its pressure rating is 5 bar. Estimate the contribution of the heat exchanger to the total cost of the project (CE Index of Equipment = 441.9). 

The cost of a carbon steel heat exchanger needs to be adjusted for the material of construction. Because of the low pressure rating, no correction for pressure is required (Table 2.5), but the cost needs to be adjusted for the material of construction. From Table 2.4, /m =2.9, and the total cost of the installed equipment can be estimated from Equation 2.6 and Table 2.7. If the project is a complete new plant, the contribution of the heat exchanger to the total cost can be estimated to be ... 

Optimization problems in process design are usually concerned with maximizing or minimizing an objective function. The objective function might typically be to maximize economic potential or minimize cost. For example, consider the recovery of heat from a hot waste stream. A heat exchanger could be installed to recover the waste heat. The heat recovery is illustrated in Figure 3.1a as a plot of temperature versus enthalpy. There is heat available in the hot stream to be recovered to preheat the cold stream. But how much heat should be recovered Expressions can be written for the recovered heat as ... 

Objective functions that allow only discrete values of the independent variable ) occur frequently in process design because the process variables assume only specific values rather than continuous ones. Examples are the cost per unit diameter of pipe, the cost per unit area for heat exchanger surface, or the insulation cost considered in Example 1.1. For a pipe, we might represent the installed cost as a function of the pipe diameter as shown in Figure 4.2 [see also Noltie (1978)]. For... 

For continuous processes the catalytic reactor, or a hybrid process if satisfactory chemical dosing equipment is already installed, appear to be a near-optimum solution still for many installations. At moderate hypochlorite concentrations, economic benefit does accrue from using the catalyst in-loop rather than end-of-pipe, but these benefits may be offset by any required investment in heat-exchange capability. At concentrations above 10 wt% the integration of decomposition into the scrubbing process is beneficial to the overall cost base of hypochlorite treatment. 

Guthrie and Garrett. It uses equipment factors to generate separate costs for each of the "disciplines associated with the installation of equipment, such as installation labor, concrete, structural steel, and piping, to obtain direct field costs for each type of equipment, e.g., heat exchangers, towers, and reactors. 

The operating experience with all these installations is satisfactory to good only some minor technical improvements, for example, exchange of sand filters, became necessary. The flow rates and temperatures of the outflowing tunnel waters show little to no seasonal variation. Therefore, this zero-cost heat source can be considered as totally reliable and sustainable. 

Methods have been developed that are able to generate a minimum-area network for any given energy recovery, AT,. The minimum-area networks developed generally employ many heat exchangers and are not an economic solution. These may be used to start an evolutionary process to develop better networks. Rather than minimum total area, the concern should be with the way in which the area is distributed among the exchangers. The installed cost of... 

If a 100,000 heat exchanger is to be added to an existing crude unit, the cost of installing it will normally be far less than the 230,000 calculated from Table 8.2. This is because the sewers, control room, and instrument loops are already in place. The foundation, piping, and insulation of the exchanger might cost 80,000 to 160,000. It is simply not possible to estimate an installed cost of one or two items of process equipment without considering each case on an individual basis. 

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