Liquid-phase decomposition of particulate mercury from hydrocarbon streams

Abstract

Particulate mercury is removed from crude oil by thermally treating the crude oil or condensate at temperatures in a range from 150° C. to 350° C. and at a sufficient pressure with subsequent cooling under maintenance of pressure to provide irreversible conversion to elemental mercury, which may be preferentially removed in a mercury removal unit.

What is claimed is: 
     
         1 . A method for the removal of mercury from a crude oil comprising:
 increasing the pressure on the crude so that it remains essentially in the liquid state for a subsequent heating step;   heating the pressurized crude to temperature in a range from 150° C. to 350° C.;   processing the crude in a thermal decomposition reactor operating in a liquid phase at LHSV of greater than or equal to 0.1 hr −1  and less than or equal to 10 hr −1  to convert at least a portion of the particulate mercury to elemental mercury)(Hg 0 );   maintaining the pressure while concurrently cooling the product from the thermal decomposition reactor to greater than or equal to 40° C. and less than or equal to 150° C.,   feeding the cooled reaction product from the thermal decomposition reactor to a unit for the preferential removal of elemental mercury.   
     
     
         2 . The method of  claim 1 , wherein the first temperature is in a range from 200° C. to 275° C. 
     
     
         3 . The method of  claim 1 , wherein the first pressure is in a range from 250 psig to 1500 psig. 
     
     
         4 . The method of  claim 1 , wherein the product is cooled from the thermal decomposition reactor to a temperature range of 70° C. or less.