Systems and processes for separating emulsified water from a fluid stream

Abstract

Low-water content organic phases can be difficult to achieve at high fluxes when water is present in an emulsified form, such as in a water-in-oil emulsion. Processes for de-emulsifying a fluid stream containing emulsified water, such as water-in-crude oil emulsions, include introduction of the fluid stream into a vessel that defines a coalescence zone. The vessel is configured to provide for simultaneous application of a centrifugal force and an electric field to the fluid stream within the coalescence zone. The simultaneous application of the centrifugal force and the electric field to the fluid stream provides for the coalescence of a portion of the emulsified water into a bulk aqueous phase. Continuous phases of the organic component and the bulk aqueous phase form in the coalescence zone and are separately removed from the vessel. The bulk aqueous phase is removed from the underside of the vessel.

1 . A process comprising:
 introducing a fluid stream comprising an organic component and emulsified water to a vessel defining a coalescence zone, the vessel configured to simultaneously apply a centrifugal force and an electric field to the fluid stream within the coalescence zone;   simultaneously applying the centrifugal force and the electric field to the fluid stream within the coalescence zone to coalesce a portion of the emulsified water into a bulk aqueous phase within the coalescence zone; and   separately removing from the vessel continuous phases of the organic component and the bulk aqueous phase, the bulk aqueous phase being removed from an underside of the vessel.   
     
     
         2 . The process of  claim 1 , wherein the vessel is a hydrocyclone. 
     
     
         3 . The process of  claim 2 , wherein the electric field is applied with an electrically insulated electrode having an elongated body located within the coalescence zone of the vessel. 
     
     
         4 . The process of  claim 3 , wherein the electrically insulated electrode has a non-concave exterior. 
     
     
         5 . The process of  claim 4 , wherein the vessel has a longitudinal axis and the electrically insulated electrode is non-parallel with respect to the longitudinal axis. 
     
     
         6 . The process of  claim 5 , wherein the vessel has a longitudinal axis and is inclined with respect to the earth's surface, thereby making an incident angle with the earth's surface in a range from 20 degrees to 60 degrees. 
     
     
         7 . The process of  claim 6 , wherein the organic component comprises a crude oil or a partially dewatered crude oil. 
     
     
         8 . The process of  claim 7 , wherein the fluid stream comprises less than 10% water by volume. 
     
     
         9 . The process of  claim 8 , wherein the fluid stream is introduced to the vessel after passing through a mechanical screen, an electrified screen, an electrocoagulator, an electroprecipitator, or any combination thereof. 
     
     
         10 . The process of  claim 9 , further comprising:
 adding a chemical to the fluid stream to further promote coalescence of the emulsified water into the bulk aqueous phase.   
     
     
         11 . The process of  claim 10 , wherein at least one of the continuous phases is removed from the vessel on a continuous basis.