Capital cost profiles

The utilisation and the on/off cycles of a CHP system affect its potential benefit. Furthermore, higher overall efficiency leads to lower fuel consumption, while longer lifetimes lead to lower annualised capital costs. Concerning the relative influence of the demand profile, the nominal electric capacity, the efficiency and the lifetime of AFC, PAFC, PEMFC and SOFC systems, target costs were found to lie in a rather wide range. 

In this expression, Fb, Fcd represent the production rates of B and CD, respectively, and Fao is the amount of fresh feed. The first term corresponds to the product value, while the second term corresponds to the cost of waste treatment for undesired products C and D. The third term corresponds to the reactor capital cost, while the fourth and the fifth terms correspond to the recycling costs. The costs incurred for maintaining a desired separation profile, C ep, is given in (PI4). 

Rolls crushers consist of two counter-rotating rolls, one of which is fixed and the other is spring-loaded. They draw feed material into a nip point , where it is crushed (Fig. 5.5). The rolls may be smooth, or profiled, which helps to draw the rock through the crusher and to reduce the slabbiness of the crushed product. Reduction ratios of only 4 1 are achievable, but the production of fines is low. The head-room requirement is lower than for impactors, but the capital cost is higher. 

Key reasons for the selection of Ausmelt technology for lead smelting by Metaleurop, Tsumeb and Korea Zinc are the excellent environmental performance, capital and operating cost profiles and process flexibility provided in a compact high intensity smelter system. 

Six standard basis profiles are available within Aspen IPE for estimating the capital cost. These model the nature of the contractor to execute the project, depending on the size of the project, as shown below. Three of the profiles are for projects to be executed by an Owner company (0, 1, and 2), and the other three are for projects to be executed by Engineering and Construction firms (3, 4, and 5). For the small depropanizer project of this example, the LOCAL CONTRACTOR is appropriate. 

To select a standard basis profile for a project, in the Project Basis view, right-click on the Basis for Capital Costs. Click Select to choose the most appropriate profile. 

The Basis for Capital Costs includes specifications for process controls, plant location, currency, wage rates, units of measure, and contractor profiles. Default values are provided for all entries, most of which need not be adjusted. 

The total exhaust stack length for the design in question is 24.4 m. The weight of platform steelwork required to fuUy support such a system would consequently be 45 tons. Recent North Sea developments have tended to be on more marginal fields, and therefore consideration of capital costs versus revenue has become crucial. With a typical installed platform cost of 3500 per ton of steelwork weight saving now takes a high profile. 

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