A method for improving the performance of using heat in a thermodynamic cycle

摘要

A method and apparatus for implementing a thermodynamic cycle involves utilizing partial distillation of a multi-component working fluid stream. At least one main enriched solution is produced which is relatively enriched with respect to the lower boiling temperature component, together with at least one lean solution which is relatively impoverished with the respect of lower boiling temperature component. The main working fluid is expanded to a low pressure level to convert energy to a usable form. This spent low pressure level working fluid is condensed by dissolving with cooling in the lean solution to regenerate an initial working fluid for reuse. A portion of the impoverished fraction may be injected into the charged gaseous main working fluid in order to obtain added work and to increase system efficiency by decreasing the temperature of the output fluid flow when the fluid flow would otherwise have been superheated. A low pressure, low temperature expanded spent fluid may be distilled using low quality heat to create an enriched solution which has a significantly higher concentration of the lower boiling component. For this enriched solution, a reduced temperature and pressure is sufficient to enable distillation. The efficiency of the cycle may be enhanced by charging the spent fluid with the lower boiling temperature component prior to distillation. This may be accomplished by lowering the pressure of the impoverished fraction to separate an additional lower boiling temperature fraction.