Heat exchange for indirect boiling

Abstract

Systems and methods relate to vaporizing water into steam, which may be utilized in applications such as bitumen production. The methods rely on indirect boiling of the water by contact with a substance such as solid particulate heated to a temperature sufficient to vaporize the water. Heating of the solid particulate may utilize pressure isolated heat exchanger units or a hot gas recirculation circuit at a pressure corresponding to that desired for the steam. Further, the water may form part of a mixture that contacts the solid particulate and includes a solvent for the bitumen in order to limit vaporization energy requirements and facilitate the production.

1 . A method of vaporizing water, comprising:
 heating solid particulate by heat exchange with hot fluids separated from the solid particulate by a thermally conductive material;   introducing the water into contact with the solid particulate heated to a temperature that results in vaporizing the water into steam; and   separating the steam from the solid particulate.   
     
     
         2 . The method according to  claim 1 , wherein the solid particulate is fluidized during the introducing of the water into contact therewith. 
     
     
         3 . The method according to  claim 1 , wherein the hot fluids include one of combustion exhaust and heated liquid sodium. 
     
     
         4 . The method according to  claim 1 , wherein the hot fluids include heated liquid sodium. 
     
     
         5 . The method according to  claim 1 , wherein the hot fluids are at a lower pressure than that surrounding the solid particulate during the heating. 
     
     
         6 . The method according to  claim 1 , wherein the heating of the solid particulate and the introducing of the water occurs in a single vessel. 
     
     
         7 . The method according to  claim 1 , further comprising circulating the solid particulate between a first vessel where the heating of the solid particulate occurs and a second vessel where the introducing of the water occurs. 
     
     
         8 . The method according to  claim 1 , wherein the heating of the solid particulate and the introducing of the water occur in separate vessels maintained at a common pressure. 
     
     
         9 . The method according to  claim 1 , wherein the water vaporizes in a riser that circulates the solid particulate back to a vessel for the heating of the solid particulate. 
     
     
         10 . The method according to  claim 1 , wherein the solid particulate includes at least one of sand, metals and cracking catalyst. 
     
     
         11 . The method according to  claim 1 , further comprising supplying the water from separated production fluid associated with a steam assisted gravity drainage bitumen recovery operation and injecting the steam into a formation during the bitumen recovery operation. 
     
     
         12 . A system for vaporizing water, comprising:
 a heat exchanger for heating solid particulate with hot fluids separated from the solid particulate by a thermally conductive material;   an inlet to a steam generating vessel to supply the water into contact with the solid particulate heated to a temperature that results in vaporizing the water into steam; and   an output to the steam generating vessel to convey the steam separated from the solid particulate.   
     
     
         13 . The system according to  claim 12 , wherein the hot fluids include one of combustion exhaust and heated liquid sodium. 
     
     
         14 . The system according to  claim 12 , wherein the heat exchanger is disposed inside the steam generating vessel. 
     
     
         15 . The system according to  claim 12 , further comprising a heating vessel that contains the heat exchanger and is coupled for circulation of the solid particulate between the steam generating vessel and the heating vessel. 
     
     
         16 . The system according to  claim 12 , further comprising a heating vessel that contains the heat exchanger and is in open pressure communication with the steam generating vessel. 
     
     
         17 . The system according to  claim 12 , wherein the steam generating vessel includes a riser that circulates the solid particulate back to a heating vessel for the heating of the solid particulate. 
     
     
         18 . The system according to  claim 12 , wherein the solid particulate includes at least one of sand, metals and cracking catalyst. 
     
     
         19 . The system according to  claim 12 , wherein the water is separated from production fluid associated with steam assisted gravity drainage bitumen recovery and the output is coupled to inject the steam into a formation. 
     
     
         20 . The system according to  claim 12 , wherein the thermally conductive material forms a tube of the heat exchanger through which one of the hot fluids and the solid particulate flow.