A method to refine the start-up scheme of compression and refrigeration systems in ethylene plants via dynamic simulation

Selection of a suitable start-up scheme for compression and refrigeration system of ethylene plants is a multi-objective problem balancing the SS production, safe operating range and precooling time. In this paper, a method is developed to select start-up schemes with sufficient safe operating range and good effort of emission reduction and energy saving based on plant devices and resources. It is found that higher SS consumption increases the process energy loss, but yields shorter precooling time and safer operating range. The method to select and determine a suitable start-up scheme is validated using industrial data.123