Heat exchanger network target total cost targets

Heat Exchanger Networks III - Capital and Total Cost Targets... 

Figure 17.9 shows a heat exchanger network designed with the minimum number of units and to satisfy the energy target at ATmi = 20°C. On the basis of the following utilities and cost data, it has a total annual cost of 14.835 x 106 ( -y 1). 

Serna-Gonzalez, M. and Ponce-Ortega, J.M. (2011) Total cost target for heat exchanger networks considering simultaneously pumping power and area effects. Applied Thermal Engineering, 31, 1964-1975. 

Increasing the chosen value of process energy consumption also increases all temperature differences available for heat recovery and hence decreases the necessary heat exchanger surface area (see Fig. 6.6). The network area can be distributed over the targeted number of units or shells to obtain a capital cost using Eq. (7.21). This capital cost can be annualized as detailed in App. A. The annualized capital cost can be traded off against the annual utility cost as shown in Fig. 6.6. The total cost shows a minimum at the optimal energy consumption. 

Once a design is known for the first two layers of the onion (i.e., reactors and separators only), the overall total cost of this design for all four layers of the onion (i.e., reactors, separators, heat exchanger network, and utilities) is simply the total cost of all reactors and separators (evaluated explicitly) plus the total cost target for heat exchanger network and utilities. 

Once a design is known for the reaction and separation systems, the overall total cost is the total cost of all reactors and separators (evaluated explicitly) plus the total cost target for heat exchanger network. 

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