Controlled Delivery of Heat Applied To A Subsurface Formation

Abstract

The present disclosure provides a method for controlling delivery of heat to a subsurface formation that includes (a) heating a first heater pattern; (b) determining an expected electrical conductivity; (c) calculating an estimated electrical conductivity; (d) comparing an estimated electrical conductivity to the expected electrical conductivity until the estimated electrical conductivity equals the expected electrical conductivity; (e) determining a first heater pattern reaction extent when the estimated electrical conductivity equals the expected electrical conductivity; and (f) when the first heater pattern reaction extent is within a target coke first heater pattern reaction extent range, one of (i) heating a second heater pattern instead of the first heater pattern and (ii) modifying the heating of the first heater pattern, and when the first heater pattern reaction extent is outside of the target coke first heater pattern reaction extent range repeating steps (a)-(e).

What is claimed is: 
     
         1 . A method for controlling delivery of heat applied to a subsurface formation, comprising:
 (a) heating a first heater pattern in the subsurface formation using a heater;   (b) determining an expected electrical conductivity of the first heater pattern;   (c) calculating an estimated electrical conductivity;   (d) comparing an estimated electrical conductivity of the first heater pattern to the expected electrical conductivity until the estimated electrical conductivity equals the expected electrical conductivity;   (e) determining a first heater pattern reaction extent of the first heater pattern when the estimated electrical conductivity equals the expected electrical conductivity; and   (f) when the first heater pattern reaction extent is within a target coke first heater pattern reaction extent range, one of (i) heating a second heater pattern instead of the first heater pattern and (ii) modifying the heating of the first heater pattern, and   when the first heater pattern reaction extent is outside of the target coke first heater pattern reaction extent range repeating steps (a)-(e).   
     
     
         2 . The method of  claim 2 , wherein determining the expected electrical conductivity comprises using electrical resistive tomography. 
     
     
         3 . The method of  claim 2 , wherein calculating the estimated electrical conductivity comprises determining how an experimental electrical conductivity changes as a function of an experimental coke heater pattern reaction extent and an experimental temperature. 
     
     
         4 . The method of  claim 3 , wherein determining how the experimental electrical conductivity changes comprises using a functional relationship equal to:
   σ= A (ε coke ) e   B(ε     coke     )T  
   where σ is the experimental electrical conductivity, A is a first functional characteristic, ε coke  is the experimental coke heater pattern reaction extent, e is an exponential function, B is a second functional characteristic, T is the experimental temperature, A(ε coke ) is that the first functional relationship is a function of the coke heater pattern reaction extent and B(ε coke ) is that the second functional relationship is a function of the coke heater pattern reaction extent.   
     
     
         5 . The method of  claim 3 , wherein calculating the estimated electrical conductivity further comprises calculating a first functional characteristic and a second functional characteristic. 
     
     
         6 . The method of  claim 5 , wherein calculating the first functional characteristic and the second functional characteristic comprises regressing a plot of the experimental electrical conductivity versus the experimental temperature. 
     
     
         7 . The method of  claim 6 , wherein calculating the estimated electrical conductivity comprises using the functional relationship, the first functional characteristic, the second functional characteristic, and one of an estimated temperature and an estimated first heater pattern reaction extent. 
     
     
         8 . A method for producing hydrocarbons from a subsurface formation while controlling delivery of heat applied to the subsurface formation, comprising:
 (a) heating a first heater pattern in the subsurface formation using a heater;   (b) determining an expected electrical conductivity of the first heater pattern;   (c) calculating an estimated electrical conductivity;   (d) comparing an estimated electrical conductivity of the first heater pattern to the expected electrical conductivity until the estimated electrical conductivity equals the expected electrical conductivity;   (e) determining a first heater pattern reaction extent of the first heater pattern when the estimated electrical conductivity equals the expected electrical conductivity;   (f) when the first heater pattern reaction extent is within a target coke first heater pattern reaction extent range, one of (i) heating a second heater pattern instead of the first heater pattern and (ii) modifying the heating of the first heater pattern, and   when the first heater pattern reaction extent is outside of the target coke first heater pattern reaction extent range repeating steps (a)-(e)   (g) mobilizing the hydrocarbons from at least one of the first heater pattern and the second heater pattern by heating the hydrocarbons; and   (h) producing the hydrocarbons.   
     
     
         9 . The method of  claim 8 , wherein the heater comprises heaters. 
     
     
         10 . The method of  claim 8 , wherein determining the expected electrical conductivity comprises using electrical resistive tomography. 
     
     
         11 . The method of  claim 8 , wherein calculating the estimated electrical conductivity comprises determining how an experimental electrical conductivity changes as a function of an experimental coke heater pattern reaction extent and an experimental temperature. 
     
     
         12 . The method of  claim 8 , wherein (g) and (h) occur when (f) occurs. 
     
     
         13 . The method of  claim 8 , wherein (g) and (h) occur after (f) occurs. 
     
     
         14 . The method of  claim 11 , wherein determining how the experimental electrical conductivity changes comprises using a functional relationship equal to:
   σ= A (ε coke ) e   B(ε     coke     )T  
   where σ is the experimental electrical conductivity, A is a first functional characteristic, ε coke  is the experimental coke heater pattern reaction extent, e is an exponential function, B is a second functional characteristic, T is the experimental temperature, A(ε coke ) is that the first functional relationship is a function of the coke heater pattern reaction extent and B(ε coke ) is that the second functional relationship is a function of the coke heater pattern reaction extent.   
     
     
         15 . The method of  claim 11 , wherein calculating the estimated electrical conductivity further comprises calculating a first functional characteristic and a second functional characteristic. 
     
     
         16 . The method of  claim 15 , wherein calculating the first functional characteristic and the second functional characteristic comprises regressing a plot of the experimental electrical conductivity versus the experimental temperature. 
     
     
         17 . The method of  claim 16 , wherein calculating the estimated electrical conductivity comprises using the functional relationship, the first functional characteristic, the second functional characteristic, and one of an estimated temperature and an estimated first heater pattern reaction extent. 
     
     
         18 . The method of  claim 16 , wherein (g) and (h) occur when (f) occurs. 
     
     
         19 . The method of  claim 16 , wherein (g) and (h) occur after (f) occurs.