Process for hydrotreatment of petroleum fractions including a heat pump circuit

Abstract

This invention describes a new process for hydrotreatment or hydrodesulfurization of petroleum fractions that is thermally coupled to a process for amine treatment that employs a heat pump circuit that is established between a hot source located on the hydrotreatment process and a cold source located on the amine treatment system. The major effect of the process according to the invention is a reduction of CO2 emissions.

1 . Process for hydrotreatment of a petroleum fraction that is thermally coupled to an amine treatment process, making it possible to separate hydrogen from hydrogen sulfide, in which the hydrotreatment process has an exchanger ( 1007 ) that makes it possible to cool the effluent of the hydrotreatment reactor ( 1003 ) to a temperature of approximately 50° C., whereby said amine treatment process has a cross-section for regeneration of said amine that employs a distillation column ( 1009 ), equipped with a reboiler ( 1010 ) that operates at a temperature of approximately 130° C., and whereby said hydrotreatment process is characterized in that it incorporates a heat pump circuit that employs a coolant circulating between the reboiler ( 1010 ) that plays the role of a hot source and the exchanger ( 1007 ) that plays the role of a cold source. 
     
     
         2 . Process for hydrotreatment of a petroleum fraction that is thermally coupled to an amine treatment process according to  claim 1 , wherein the heat pump circuit uses a coolant whose circuit is as follows:
 The coolant ( 206 ,  207 ,  208 ,  209 ) in the liquid-vapor state ( 208 ) evaporates in the exchanger ( 1007 ) by extracting the calories of the reaction effluent ( 111 ) for producing a vapor ( 209 ) whose temperature and pressure are increased by the compressor ( 1011 ); the high-pressure and high-temperature vapor stream ( 206 ) obtained from the compressor ( 1011 ) is condensed in the reboiler ( 1010 ) by producing a pressurized liquid stream ( 207 ) whose temperature is lowered by expansion in the valve ( 1012 ); and the resulting liquid ( 208 ) is then partially vaporized and returns to the exchanger ( 1007 ) in the form of a liquid-vapor mixture.   
     
     
         3 . Process for hydrotreatment of a petroleum fraction that is thermally coupled to an amine treatment process according to  claim 2 , wherein the coolant ( 208 ) has a boiling point that is less than or equal to  60 ° C., and preferably less than 50° C. for a pressure that is less than 5 bar, and preferably less than 2 bar. 
     
     
         4 . Process for hydrotreatment of a petroleum fraction that is thermally coupled to an amine treatment process according to  claim 2 , wherein the coolant ( 208 ) has a condensation temperature that is greater than 120° C. and preferably greater than 130° C., for a pressure that is greater than 1 bar. 
     
     
         5 . Process for hydrotreatment of a petroleum fraction that is thermally coupled to an amine treatment process according to  claim 2 , wherein the coolant ( 208 ) that supplies the heat pump circuit is selected from the group that is formed by propane, butane, and pentane. 
     
     
         6 . Process for hydrotreatment of a petroleum fraction that is thermally coupled to an amine treatment process according to  claim 2 , wherein the coolant ( 208 ) that supplies the heat pump circuit is selected from the group that is formed by alcohols and diols, having a carbon atom number of between 3 and 10.