Eliminating fouling in hydrocarbon pipelines by electrical techniques

Abstract

A method for eliminating hydrocarbon fouling and reducing pumping power during hydrocarbon transportation. A dielectric layer covers the inner surface of a pipeline for transporting a water-hydrocarbon mixture. A proximity electrode is immersed in the water-hydrocarbon mixture, and an electrical voltage is applied across the dielectric layer. A buffer layer of water is formed on the dielectric layer since water is electrically attracted from the water-hydrocarbon mixture. This water layer, located between the dielectric layer and the water-hydrocarbon mixture, eliminates hydrocarbon fouling on the inner surface of the pipeline or any other internal surface that needs fouling protection. Alternatively, the dielectric layer covers an outer surface of the pipeline and is covered by an external conducting layer. Applying a potential difference between the proximity electrode and the external conducting layer still forms a water buffer layer between the inner surface and the water-hydrocarbon mixture, which eliminates hydrocarbon fouling.

1 . A method for eliminating hydrocarbon fouling in transporting and storing a water-hydrocarbon mixture, the method comprising:
 covering an inner surface of a pipeline for transporting and storing said water-hydrocarbon mixture with a dielectric layer;   applying a potential difference across said dielectric layer established by applying an electrical potential to a proximity electrode immersed in a solution of said water-hydrocarbon mixture and applying an electrical potential to said pipeline; and   forming a buffer layer of water on top of said dielectric layer by electrically attracting water from said water-hydrocarbon mixture to said buffer layer by applying said potential difference across said dielectric layer, wherein said water buffer layer is located between said dielectric layer and said water-hydrocarbon mixture thereby eliminating hydrocarbon fouling on said inner surface of said pipeline.   
     
     
         2 . The method as recited in  claim 1 , wherein hydrocarbons in said water-hydrocarbon mixture comprise one or more of the following: asphaltenes, waxes, hydrates and scales. 
     
     
         3 . The method as recited in  claim 1 , wherein said dielectric layer has antifouling chemical properties and/or low surface energy. 
     
     
         4 . The method as recited in  claim 1 , wherein said dielectric layer comprises one of the following: an oxide, a polymer and a ceramic. 
     
     
         5 . A transportation mechanism for transporting hydrocarbons, the mechanism comprises:
 a pipeline for transporting a water-hydrocarbon mixture;   a dielectric layer covering an inner surface of said pipeline;   a proximity electrode immersed in said water-hydrocarbon mixture, wherein a potential difference is applied across said dielectric layer established by applying an electrical potential to said proximity electrode and applying an electrical potential to said pipeline; and   a buffer layer of water on top of said dielectric layer, wherein said water buffer layer comprises water electrically attracted from said water-hydrocarbon mixture by applying said potential difference across said dielectric layer, wherein said water buffer layer is located between said dielectric layer and said water-hydrocarbon mixture thereby eliminating hydrocarbon fouling on an inner surface of said pipeline.   
     
     
         6 . The transportation mechanism as recited in  claim 5 , wherein hydrocarbons in said water-hydrocarbon mixture comprise one or more of the following: asphaltenes, waxes and hydrates. 
     
     
         7 . The transportation mechanism as recited in  claim 5 , wherein said dielectric layer has antifouling chemical properties and/or low surface energy. 
     
     
         8 . The transportation mechanism as recited in  claim 5 , wherein said dielectric layer comprises one of the following: an oxide, a polymer and a ceramic. 
     
     
         9 . A method for eliminating hydrocarbon fouling in transporting and storing a water-hydrocarbon mixture, the method comprising:
 covering an outer surface of a pipeline for transporting and storing said water-hydrocarbon mixture with a dielectric layer;   covering said dielectric layer with an external conducting layer;   applying a potential difference across said dielectric layer established by applying an electrical potential to a proximity electrode immersed in a solution of said water-hydrocarbon mixture and applying an electrical potential to said external conducting layer; and   forming a buffer layer of water on top of an inner surface of said pipeline by electrically attracting water from said water-hydrocarbon mixture to said buffer layer by applying said potential difference across said dielectric layer, wherein said water buffer layer is located between said inner surface of said pipeline and said water-hydrocarbon mixture thereby eliminating hydrocarbon fouling on said inner surface of said pipeline.   
     
     
         10 . The method as recited in  claim 9 , wherein hydrocarbons in said water-hydrocarbon mixture comprise one or more of the following: asphaltenes, waxes and hydrates. 
     
     
         11 . The method as recited in  claim 9 , wherein said dielectric layer comprises one of the following: an oxide, a polymer and a ceramic. 
     
     
         12 . A transportation mechanism for transporting hydrocarbons, the mechanism comprises:
 a pipeline for transporting a water-hydrocarbon mixture;   a dielectric layer covering an outer surface of said pipeline;   an external conducting layer covering said dielectric layer;   a proximity electrode immersed in said water-hydrocarbon mixture, wherein a potential difference is applied across said dielectric layer established by applying an electrical potential to said proximity electrode and applying said electrical potential to said external conducting layer; and   a buffer layer of water on top of an inner surface of said pipeline, wherein said water buffer layer comprises water electrically attracted from said water-hydrocarbon mixture by applying said potential difference across said dielectric layer, wherein said water buffer layer is located between said inner surface of said pipeline and said water-hydrocarbon mixture thereby eliminating hydrocarbon fouling on said inner surface of said pipeline.   
     
     
         13 . The transportation mechanism as recited in  claim 12 , wherein hydrocarbons in said water-hydrocarbon mixture comprise one or more of the following: asphaltenes, waxes and hydrates. 
     
     
         14 . The transportation mechanism as recited in  claim 12 , wherein said dielectric layer comprises one of the following: an oxide, a polymer and a ceramic. 
     
     
         15 . A method for eliminating hydrocarbon fouling in transporting and storing a water-hydrocarbon mixture, the method comprising:
 covering an outer surface of a pipeline for transporting said water-hydrocarbon mixture with an external capacitance;   applying a potential difference across said external capacitance established by applying an electrical potential to a proximity electrode immersed in a solution of said water-hydrocarbon mixture and applying an electrical potential to said external capacitance; and   forming a buffer layer of water on top of an inner surface of said pipeline by electrically attracting water from said water-hydrocarbon mixture to said buffer layer by applying said potential difference across said external capacitance, wherein said water buffer layer is located between said inner surface of said pipeline and said water-hydrocarbon mixture thereby eliminating hydrocarbon fouling on said inner surface of said pipeline.   
     
     
         16 . The method as recited in  claim 15 , wherein hydrocarbons in said water-hydrocarbon mixture comprise one or more of the following: asphaltenes, waxes and hydrates. 
     
     
         17 . The method as recited in  claim 15 , wherein said external capacitance comprises a solid-state capacitor. 
     
     
         18 . A transportation mechanism for transporting hydrocarbons, the mechanism comprises:
 a pipeline for transporting a water-hydrocarbon mixture;   an external capacitance covering an outer surface of said pipeline;   a proximity electrode immersed in said water-hydrocarbon mixture, wherein a potential difference is applied across said external capacitance established by applying an electrical potential to said proximity electrode and applying an electrical potential to said external capacitance; and   a buffer layer of water on top of an inner surface of said pipeline, wherein said water buffer layer comprises water electrically attracted from said water-hydrocarbon mixture by applying said potential difference across said external capacitance, wherein said water buffer layer is located between said inner surface of said pipeline and said water-hydrocarbon mixture thereby eliminating hydrocarbon fouling on said inner surface of said pipeline.   
     
     
         19 . The transportation mechanism as recited in  claim 18 , wherein hydrocarbons in said water-hydrocarbon mixture comprise one or more of the following: asphaltenes, waxes and hydrates. 
     
     
         20 . The transportation mechanism as recited in  claim 18 , wherein said external capacitance comprises a solid-state capacitor. 
     
     
         21 . A method for eliminating hydrocarbon fouling in transporting and storing a water-hydrocarbon mixture, the method comprising:
 covering an inner surface of a pipeline for transporting said water-hydrocarbon mixture with a dielectric layer;   applying a potential difference across said dielectric layer established by applying an electrical potential to an electrode mesh covering said dielectric layer and applying an electrical potential to said pipeline; and   forming a buffer layer of water on top of said electrode mesh by electrically attracting water from said water-hydrocarbon mixture to said buffer layer by applying said potential difference across said dielectric layer, wherein said water buffer layer is located between said electrode mesh and said water-hydrocarbon mixture thereby eliminating hydrocarbon fouling on said inner surface of said pipeline.   
     
     
         22 . The method as recited in  claim 21 , wherein hydrocarbons in said water-hydrocarbon mixture comprise one or more of the following: asphaltenes, waxes and hydrates. 
     
     
         23 . A transportation mechanism for transporting hydrocarbons, the mechanism comprises:
 a pipeline for transporting a water-hydrocarbon mixture;   a dielectric layer covering an inner surface of said pipeline;   an electrode mesh covering said dielectric layer, wherein a potential difference is applied across said dielectric layer established by applying an electrical potential to said electrode mesh and applying an electrical potential to said pipeline; and   a buffer layer of water on top of said dielectric layer, wherein said water buffer layer comprises water electrically attracted from said water-hydrocarbon mixture by applying said potential difference across said dielectric layer, wherein said water buffer layer is located between said electrode mesh and said water-hydrocarbon mixture thereby eliminating hydrocarbon fouling on an inner surface of said pipeline.   
     
     
         24 . The transportation mechanism as recited in  claim 23 , wherein hydrocarbons in said water-hydrocarbon mixture comprise one or more of the following: asphaltenes, waxes and hydrates.