Introducing a new parameter for evaluating the degree of integration in cryogenic liquid recovery processes

Supplying the required refrigeration is one of the most important parameters in design of cryogenic liquid recovery processes and different configurations have been introduced in order to gain higher liquid recoveries or minimum total cost. However, due to the advantages and disadvantages of current invented configurations and changeable operating conditions of such processes and the different prices of the products and operating costs, selection of a configuration as the best one is not easy. In this work a new parameter for evaluating the degree of integration of such processes is introduced. This parameter can evaluate the degree of integration based on the recovered refrigeration from the process streams against the required refrigeration which is gained by different sources. The exergy concept was used in order to calculate the Integration Degree (IDG). IDG was defined for two kinds of processes; with and without external refrigeration. The results showed that the kind of configuration is a basic variable which can affect the IDG significantly, and influences of the other parameters are not significant in comparison. Consequently it can be said that with increasing IDG the process performance and integrity of the process increase and it can be used in optimization problems.