Thermal Design and Analysis of Deethanizer Thermosiphon Reboiler in Bushehr Ethane Recovery and Fractionation Plant (CRFP) Thermal Analysis and calculation performed by Aspen HYSYS V7.3 and HTRI Xchanger Suite 6.0

The following description briefly explains, thermal analysis and calculation has been performed by EIED Heat Transfer Equipment team (Process & Mechanical Dept.) in Detail Engineering phase of Bushehr Ethane Recovery and Fractionation Plant (CRFP).In Busheher Ethane Recovery project, Ethane Rich Feed Gas after sweetening, dehydration, removing the Mercaptans, Hg and As will be transferred to C2 Recovery and Fractionation Plant (CRFP) consists of four main process Units as C2 Recovery Unit, C3 + Polishing Unit, Fractionation Unit and Refrigerants Systems.The purpose of the C2 Recovery Unit is processing of sweetened dried gas from Dehydration Unit to recover most of the ethane and heavier components from the natural feed gas by means of Demethanizer and Deethanizer sections.Referring to Fig.1, in Deethanizer Column (05-310-T-2) being operated at approximately 22 barg (at the top) the Ethane Product are recovered at the top while the heavier components (C3 +) are removed in the bottom.The Deethanizer Reboiler (05-310-E-8) supplies the necessary heat in the column.The Deethanizer Column temperature is controlled by temperature controller located in the lower section of the column in cascade with flow controller on the LP steam inlet to the Deethanizer Reboiler (05-310-E-8). In Detail Design stage of CRFP Bushehr project, EIED Heat Transfer Equipment team has checked thermal design of Deethanizer thermosiphon reboiler had been performed by the Basic thermal Designer. After studying, analyzing and software calculation we detected design of the mentioned thermosiphon reboiler shall be changed in order to have a proper natural circulation and achieving required heat duty for the column accordingly. You can find an abstracted report from our thermal observation in the following sections.