Capital cost estimating

Estimation of the capital cost required to build a plant is a critically important step in process design. Capital costs of process equipment can be estimated using commercial software or from correlations based on accumulated project data. Components of capital cost are introduced. The accuracy of capital cost estimates depends on the amount of detailed design information and vendor information available and increases as projects proceed. The AACE International cost estimate classes are described. Simple methods for cost estimating such as step-count methods, reverse engineering, and unit-level correlations are described. Approximate correlations for plant costs and for costs of typical unit operations and types of process equipment are given. Installed costs can be estimated by applying an installation factor to the basic equipment (bare module) cost. Methods for updating cost estimates based on historic data and for estimating costs in different locations are given. The use of commercial cost estimating tools such as Aspen Capital Cost Estimator and Cleopatra Enterprise is introduced.