STUDY ON THE RECOVERY OF THERMAL ENERGY FROM TECHNOLOGICAL FLOWS IN THE COKING PLANT

Abstract

In this paper, the current heat recovery system from delayed coking in a Romanian refinery is analyzed, the current system is simulated, and an additional heat recovery variant is proposed and simulated. Currently, the raw material is preheated with the following hot streams: light and heavy diesel (LDO and HDO) as final products of the plant and recirculated heavy diesel (RDO). After preheating the raw material, the final temperatures of the hot process streams indicate a thermal energy reserve that can be harnessed. Hot technological flows, after preheating the raw material, pass through air coolers, thus a large part of the thermal energy is lost in the environment. Since the temperature level of the hot technological flows is quite high after the preheating of the raw material - the outlet temperatures LDO is 167°C, HDO is 277°C and RDO is 245°C - the paper proposes two options for recovery of the heat from technological flows that have a reserve of thermal energy, obtaining low-pressure saturated steam. The simulation of raw material preheating systems, the actual and the proposed variant, were made with the PRO/II software.

Keywords

• heat recovery
• heat regeneration
• simulation
• flow