Abstract
A method of determining rational design margin of unit operation in a process is developed by taking account of parameter uncertainties usually involved in actual process system design. Since decision variables which are to be determined in process system design consist of design variables and manipulating variables, design may be estimated rationally by considering admissible ranges of manipulating variables. The method proposed in this paper is applied to design of a simple chemical reaction process with recycle, and the result obtained by this method is compared with that obtained by the method proposed previously by the authors.
