Process for producing Hydrocarbon fluids combining in situ heating, a power plant and a gas plant

Abstract

An in situ method of producing hydrocarbon fluids from an organic-rich rock formation is provided. The method may include heating an organic-rich rock formation, for example an oil shale formation, in situ to pyrolyze formation hydrocarbons, for example kerogen, to form a production fluid containing hydrocarbon fluids. The method may include separating the production fluid into at least a gas stream and a liquid stream, where the gas stream is a low BTU gas stream. The low BTU gas stream is then fed to a gas turbine where it is combusted and is used to generate electricity.

1 . An in situ method of producing hydrocarbon fluids from an organic-rich rock formation, comprising:
 a) heating an organic-rich rock formation in situ;   b) producing a production fluid from the organic-rich rock formation, the production fluid having been at least partially generated as a result of pyrolysis of formation hydrocarbons located in the organic-rich rock formation, the production fluid comprising hydrocarbon fluids;   c) separating the production fluid into at least a first gas stream and a first liquid stream, wherein the first gas stream comprises greater than 10 mole percent hydrocarbon gas and greater than 10 mole percent carbon dioxide;   d) passing the first gas stream through a first gas turbine to form a first gas turbine exhaust stream, the first gas turbine being configured to provide energy to a first electrical generator; and   e) generating electricity in the first electrical generator in response to the gas turbine exhaust stream.   
   
   
       2 . The method of  claim 1 , wherein the formation hydrocarbons in the organic-rich rock formation comprise heavy hydrocarbons. 
   
   
       3 . The method of  claim 1 , wherein the organic-rich rock formation is an oil shale formation. 
   
   
       4 . The method of  claim 3 , further comprising:
 f) passing at least a portion of the generated electricity from the first electrical generator to a heater, the heater providing at least a portion of the in situ organic-rich rock formation heating.   
   
   
       5 . The method of  claim 4 , wherein the heater is an electrical resistance heater located in the organic-rich rock formation. 
   
   
       6 . The method of  claim 3 , wherein the step a) of heating the organic-rich rock formation in situ results in at least a portion of the organic-rich rock formation reaching a temperature of 270° C. or greater. 
   
   
       7 . The method of  claim 3 , wherein the step c) of separating the production fluid further comprises producing an LPG stream comprised primarily of C 3  and C 4  hydrocarbons. 
   
   
       8 . The method of  claim 3 , wherein the step c) of separating the production fluid further comprises removing hydrogen sulfide from the first gas stream. 
   
   
       9 . The method of  claim 3 , wherein the first gas stream is comprised primarily of C 1  and C 2  hydrocarbons on a molar basis. 
   
   
       10 . The method of  claim 3 , wherein the first gas stream has a CO 2  content that is greater than 20 mole percent. 
   
   
       11 . The method of  claim 10 , wherein the CO 2  content of the first gas stream is less than 45 mole percent. 
   
   
       12 . The method of  claim 3 , wherein the first gas stream has a lower heating value of less than 800 BTU/SCF. 
   
   
       13 . The method of  claim 12 , wherein the first gas stream has a lower heating value of greater than 150 BTU/SCF. 
   
   
       14 . The method of  claim 3 , wherein the production fluid contains a condensable hydrocarbon portion and a non-condensable hydrocarbon portion, and the ratio of the non-condensable hydrocarbon portion to the condensable hydrocarbon portion is greater than 700 standard cubic feet of gas per barrel of liquid. 
   
   
       15 . The method of  claim 3 , wherein the first gas stream further comprises hydrogen gas, the amount of hydrogen gas in the first gas stream being greater than 50 percent of the hydrogen gas contained in the production fluid. 
   
   
       16 . The method of  claim 3 , wherein the first gas stream has a substantially constant H 2  to CO 2  molar ratio. 
   
   
       17 . The method of  claim 16 , wherein the first gas stream has an H 2  to CO 2  molar ratio between 0.1 to 2.0. 
   
   
       18 . The method of  claim 3 , wherein the first gas stream has a substantially constant ethane to CO 2  molar ratio. 
   
   
       19 . The method of  claim 18 , wherein the ethane to CO 2  molar ratio of the first gas stream on an average daily basis varies by less than 15 percent over a 7 day period. 
   
   
       20 . The method of  claim 3 , further comprising:
 f) feeding the first gas turbine exhaust stream to a steam boiler, the first gas turbine exhaust stream thereby providing heat to the steam boiler;   g) producing steam in the steam boiler; and   h) feeding the steam to a steam turbine, wherein the steam turbine is configured to provide energy to a second electrical generator.   
   
   
       21 . The method of  claim 20 , wherein greater than 80 percent of the energy used to heat the organic-rich rock formation in situ is provided by electricity generated in the first electrical generator and the second electrical generator. 
   
   
       22 . The method of  claim 20 , wherein the steam boiler is a supercritical boiler or a supplementally fired steam boiler. 
   
   
       23 . The method of  claim 3 , wherein the first gas stream is monitored for one or more properties selected from gas composition, temperature, heating value, specific gravity, Wobbe Index, Modified Wobbe Index, dew point, flammability limit, flame velocity, and combinations thereof. 
   
   
       24 . The method of  claim 3 , wherein the step of separating the production fluid is adjusted to meet a specification of the first gas stream, the first liquid stream, or both. 
   
   
       25 . The method of  claim 24 , wherein the specification is for the first gas stream and the specification includes the concentration of one or more of C 2  and higher hydrocarbons, C 3  and higher hydrocarbons, carbon dioxide, hydrogen gas, ethane, ethylene, propane and combinations thereof. 
   
   
       26 . The method of  claim 24 , further comprising:
 f) blending a second gas stream with the first gas stream to meet the specification, the second gas stream including hydrocarbon gas from a source other than the production fluid.   
   
   
       27 . The method of  claim 3 , wherein the step of heating the organic-rich rock formation in situ includes:
 i) heating a first portion of the organic-rich rock formation in situ commencing at a first time;   ii) heating a second portion of the organic-rich rock formation in situ commencing at a second different time.   
   
   
       28 . The method of  claim 27 , wherein the second time is chosen to meet a specification of the first gas stream. 
   
   
       29 . The method of  claim 8 , wherein removing hydrogen sulfide from the first gas stream is accomplished using an iron redox process. 
   
   
       30 . An in situ method of producing hydrocarbon fluids from an organic-rich rock formation, comprising:
 a) heating an organic-rich rock formation in situ;   b) producing a production fluid from the organic-rich rock formation, the production fluid having been at least partially generated as a result of pyrolysis of formation hydrocarbons located in the organic-rich rock formation, the production fluid comprising hydrocarbon fluids;   c) separating the production fluid into at least a first gas stream and a first liquid stream, wherein the first gas stream comprises greater than 10 mole percent hydrocarbon gas and has a lower heating value of less than 800 BTU/SCF (British thermal unit per standard cubic foot);   d) passing the first gas stream through a first gas turbine to form a first gas turbine exhaust stream, the first gas turbine being configured to provide energy to a first electrical generator; and   e) generating electricity in the first electrical generator in response to the gas turbine exhaust stream.   
   
   
       31 . The method of  claim 30 , wherein the formation hydrocarbons in the organic-rich rock formation comprise heavy hydrocarbons. 
   
   
       32 . The method of  claim 30 , wherein the organic-rich rock formation is an oil shale formation. 
   
   
       33 . The method of  claim 32 , further comprising:
 f) passing at least a portion of the generated electricity from the first electrical generator to an electrical resistance heater located in the organic-rich rock formation, the heater providing at least a portion of the in situ organic-rich rock formation heating.   
   
   
       34 . The method of  claim 32 , wherein the step a) of heating the organic-rich rock formation in situ results in at least a portion of the organic-rich rock formation reaching a temperature of 270° C. or greater. 
   
   
       35 . The method of  claim 32 , wherein the first gas stream is comprised primarily of C 1  and C 2  hydrocarbons on a molar basis. 
   
   
       36 . The method of  claim 35 , wherein the first gas stream has a CO 2  content that is greater than 10 mole percent. 
   
   
       37 . The method of  claim 36 , wherein the first gas stream has a CO 2  content that is greater than 20 mole percent. 
   
   
       38 . The method of  claim 37 , wherein the CO 2  content of the first gas stream is less than 45 mole percent. 
   
   
       39 . The method of  claim 38 , wherein the first gas stream has a lower heating value of less than 600 BTU/SCF. 
   
   
       40 . The method of  claim 39 , wherein the first gas stream has a lower heating value of greater than 150 BTU/SCF. 
   
   
       41 . The method of  claim 32 , wherein the production fluid contains a condensable hydrocarbon portion and a non-condensable hydrocarbon portion, and the ratio of the non-condensable hydrocarbon portion to the condensable hydrocarbon portion is greater than 700 standard cubic feet of gas per barrel of liquid. 
   
   
       42 . The method of  claim 32 , wherein the first gas stream further comprises hydrogen gas, the amount of hydrogen gas in the first gas stream being greater than 50 percent of the hydrogen gas contained in the production fluid. 
   
   
       43 . The method of  claim 32 , wherein the first gas stream has a substantially constant H 2  to CO 2  molar ratio. 
   
   
       44 . The method of  claim 43 , wherein the first gas stream has an H 2  to CO 2  molar ratio between 0.1 to 2.0. 
   
   
       45 . The method of  claim 32 , wherein the first gas stream has a substantially constant ethane to CO 2  molar ratio. 
   
   
       46 . The method of  claim 35 , wherein the first gas stream is greater than 20 mole percent methane. 
   
   
       47 . The method of  claim 32 , further comprising:
 f) feeding the first gas turbine exhaust stream to a steam boiler, the first gas turbine exhaust stream thereby providing heat to the steam boiler, and   g) producing steam in the steam boiler.   h) feeding the steam to a steam turbine, wherein the steam turbine is configured to provide energy to a second electrical generator.   
   
   
       48 . The method of  claim 47 , wherein greater than 80 percent of the energy used to heat the organic-rich rock formation in situ is provided by electricity generated in the first electrical generator and the second electrical generator. 
   
   
       49 . The method of  claim 47 , wherein the steam boiler is a supercritical boiler or a supplementally fired steam boiler. 
   
   
       50 . The method of  claim 32 , wherein the first gas stream is monitored for one or more properties selected from gas composition, temperature, heating value, specific gravity, Wobbe Index, Modified Wobbe Index, dew point, flammability limit, flame velocity, and combinations thereof. 
   
   
       51 . The method of  claim 32 , wherein the step of heating the organic-rich rock formation in situ includes:
 i) heating a first portion of the organic-rich rock formation in situ commencing at a first time;   ii) heating a second portion of the organic-rich rock formation in situ commencing at a second different time.   
   
   
       52 . An in situ method of producing hydrocarbon fluids from an organic-rich rock formation, comprising:
 a) heating an organic-rich rock formation in situ;   b) producing a production fluid from the organic-rich rock formation, the production fluid having been at least partially generated as a result of pyrolysis of formation hydrocarbons located in the organic-rich rock formation, the production fluid comprising hydrocarbon fluids;   c) separating the production fluid into at least a first gas stream and a first liquid stream, wherein the first gas stream comprises at least hydrocarbon gas;   d) monitoring the first gas stream to determine a first property of the first gas stream prior to substantial combustion of the first gas stream in a first gas turbine combustor;   e) adjusting a control measure to change the first property of the first gas stream;   f) passing the first gas stream through a first gas turbine to form a first gas turbine exhaust stream, the first gas turbine being configured to provide energy to a first electrical generator; and   g) generating electricity in the first electrical generator in response to the gas turbine exhaust stream.   
   
   
       53 . The method of  claim 52 , wherein the formation hydrocarbons in the organic-rich rock formation comprise heavy hydrocarbons. 
   
   
       54 . The method of  claim 52 , wherein the organic-rich rock formation is an oil shale formation. 
   
   
       55 . The method of  claim 54 , further comprising:
 f) passing at least a portion of the generated electricity from the first electrical generator to an electrical resistance heater located in the organic-rich rock formation, the heater providing at least a portion of the in situ organic-rich rock formation heating.   
   
   
       56 . The method of  claim 54 , wherein the step a) of heating the organic-rich rock formation in situ results in at least a portion of the organic-rich rock formation reaching a temperature of 270° C. or greater. 
   
   
       57 . The method of  claim 54 , wherein the first gas stream is comprised primarily of C 1  and
 C 2  hydrocarbons on a molar basis.   
   
   
       58 . The method of  claim 54 , wherein the first gas stream has a CO 2  content that is greater than 20 mole percent. 
   
   
       59 . The method of  claim 54 , wherein the first gas stream has a lower heating value of less than 800 BTU/SCF. 
   
   
       60 . The method of  claim 59 , wherein the first gas stream has a lower heating value of greater than 150 BTU/SCF. 
   
   
       61 . The method of  claim 54 , wherein the production fluid contains a condensable hydrocarbon portion and a non-condensable hydrocarbon portion, and the ratio of the non-condensable hydrocarbon portion to the condensable hydrocarbon portion is greater than 700 standard cubic feet of gas per barrel of liquid. 
   
   
       62 . The method of  claim 54 , wherein the first gas stream has a substantially constant H 2  to CO 2  molar ratio. 
   
   
       63 . The method of  claim 62 , wherein the first gas stream has an H 2  to CO 2  molar ratio between 0.1 to 2.0. 
   
   
       64 . The method of  claim 54 , wherein the first gas stream has a substantially constant ethane to CO 2  molar ratio. 
   
   
       65 . The method of  claim 57 , wherein the first gas stream is greater than 20 mole percent methane. 
   
   
       66 . The method of  claim 54 , further comprising:
 f) feeding the first gas turbine exhaust stream to a steam boiler, the first gas turbine exhaust stream thereby providing heat to the steam boiler, and   g) producing steam in the steam boiler.   h) feeding the steam to a steam turbine, wherein the steam turbine is configured to provide energy to a second electrical generator.   
   
   
       67 . The method of  claim 66 , wherein greater than 80 percent of the energy used to heat the organic-rich rock formation in situ is provided by electricity generated in the first electrical generator and the second electrical generator. 
   
   
       68 . The method of  claim 54 , wherein the first property is one or more properties selected from gas composition, temperature, heating value, specific gravity, Wobbe Index, Modified Wobbe Index, dew point, flammability limit, flame velocity, and combinations thereof. 
   
   
       69 . The method of  claim 54 , wherein the step of separating the production fluid is adjusted to meet a specification of the first gas stream, the first liquid stream, or both. 
   
   
       70 . The method of  claim 69 , wherein the specification is for the first gas stream and the specification includes the concentration of one or more of C 2  and higher hydrocarbons, C 3  and higher hydrocarbons, carbon dioxide, hydrogen gas, ethane, ethylene, propane and combinations thereof. 
   
   
       71 . The method of  claim 69 , further comprising:
 f) blending a second gas stream with the first gas stream to meet the specification, the second gas stream including hydrocarbon gas from a source other than the production fluid.   
   
   
       72 . An in situ method of producing hydrocarbon fluids from an organic-rich rock formation, comprising:
 a) heating the organic-rich rock formation in situ with an electrical resistance heater configured to produce heat from electricity;   b) producing a production fluid from the organic-rich rock formation, the production fluid having been at least partially generated as a result of pyrolysis of formation hydrocarbons located in the organic-rich rock formation, the production fluid comprising hydrocarbon fluids;   c) separating the production fluid into at least a first gas stream and a first liquid stream, wherein the first gas stream comprises greater than 5 mol percent hydrocarbon gas;   d) passing the first gas stream through a gas turbine to form a gas turbine exhaust stream, the gas turbine being configured to provide energy to a first electrical generator;   e) generating electricity in the first electrical generator in response to the gas turbine exhaust stream;   f) passing the gas turbine exhaust stream to a steam generator to produce steam;   g) passing the steam through a steam turbine, the steam turbine configured to provide energy to a second electrical generator in response to the steam; and   h) generating electricity in the second electrical generator.   
   
   
       73 . The method of  claim 72 , wherein the formation hydrocarbons in the organic-rich rock formation comprise heavy hydrocarbons. 
   
   
       74 . The method of  claim 72 , wherein the organic-rich rock formation is an oil shale formation. 
   
   
       75 . The method of  claim 74 , further comprising:
 f) passing at least a portion of the generated electricity from the first electrical generator to am electrical resistance heater located in the organic-rich rock formation, the heater providing at least a portion of the in situ organic-rich rock formation heating.   
   
   
       76 . The method of  claim 74 , wherein the first gas stream is comprised primarily of C 1  and C 2  hydrocarbons on a molar basis. 
   
   
       77 . The method of  claim 74 , wherein the first gas stream has a CO 2  content that is greater than 20 mole percent. 
   
   
       78 . The method of  claim 74 , wherein the first gas stream has a lower heating value of less than 800 BTU/SCF. 
   
   
       79 . The method of  claim 78 , wherein the first gas stream has a lower heating value of greater than 150 BTU/SCF. 
   
   
       80 . The method of  claim 74 , wherein the first electrical generator and second electrical generator are the same. 
   
   
       81 . The method of  claim 74 , wherein greater than 80 percent of the energy used to heat the organic-rich rock formation in situ is provided by electricity generated in the first electrical generator and the second electrical generator. 
   
   
       82 . The method of  claim 74 , wherein the step of heating the organic-rich rock formation in situ includes:
 i) heating a first portion of the organic-rich rock formation in situ commencing at a first time;   ii) heating a second portion of the organic-rich rock formation in situ commencing at a second different time.   
   
   
       83 . An in situ method of producing hydrocarbon fluids from an organic-rich rock formation, comprising:
 a) heating an organic-rich rock formation in situ at least partially through electrical resistance heating;   b) producing a production fluid from the organic-rich rock formation, the production fluid having been at least partially generated as a result of pyrolysis of formation hydrocarbons located in the organic-rich rock formation, the production fluid comprising hydrocarbon fluids;   c) separating the production fluid into at least a first gas stream and a first liquid stream, wherein the first gas stream comprises greater than 5 mole percent hydrocarbon gas and greater than 10 mole percent carbon dioxide;   d) passing the first gas stream through a first gas turbine to form a first gas turbine exhaust stream, the first gas turbine being configured to provide energy to a first electrical generator; and   e) generating electricity in the first electrical generator in response to the gas turbine exhaust stream.   
   
   
       84 . The method of  claim 83 , wherein the formation hydrocarbons in the organic-rich rock formation comprise heavy hydrocarbons. 
   
   
       85 . The method of  claim 83 , wherein the organic-rich rock formation is an oil shale formation. 
   
   
       86 . The method of  claim 85 , wherein the first gas stream is comprised primarily of C 1  and C 2  hydrocarbons on a molar basis. 
   
   
       87 . The method of  claim 85 , wherein the first gas stream has a CO 2  content that is greater than 20 mole percent. 
   
   
       88 . The method of  claim 85 , wherein the first gas stream has a lower heating value of less than 800 BTU/SCF. 
   
   
       89 . The method of  claim 88 , wherein the first gas stream has a lower heating value of greater than 150 BTU/SCF. 
   
   
       90 . The method of  claim 85 , further comprising:
 f) feeding the first gas turbine exhaust stream to a steam boiler, the first gas turbine exhaust stream thereby providing heat to the steam boiler, and   g) producing steam in the steam boiler.   h) feeding the steam to a steam turbine, wherein the steam turbine is configured to provide energy to a second electrical generator.   
   
   
       91 . The method of  claim 90 , wherein greater than 80 percent of the energy used to heat the organic-rich rock formation in situ is provided by electricity generated in the first electrical generator and the second electrical generator. 
   
   
       92 . The method of  claim 85 , wherein the step of heating the organic-rich rock formation in situ includes:
 i) heating a first portion of the organic-rich rock formation in situ commencing at a first time;   ii) heating a second portion of the organic-rich rock formation in situ commencing at a second different time.   
   
   
       93 . An in situ method of producing hydrocarbon fluids from an organic-rich rock formation, comprising:
 a) heating an organic-rich rock formation in situ at least partially through electrical resistance heating;   b) producing a production fluid from the organic-rich rock formation, the production fluid having been at least partially generated as a result of pyrolysis of formation hydrocarbons located in the organic-rich rock formation, the production fluid comprising hydrocarbon fluids;   c) separating the production fluid into at least a first gas stream and a first liquid stream, wherein the first gas stream comprises greater than 5 mole percent hydrocarbon gas and has a heating value of less than 800 BTU/SCF;   d) passing the first gas stream through a first gas turbine to form a first gas turbine exhaust stream, the first gas turbine being configured to provide energy to a first electrical generator; and   e) generating electricity in the first electrical generator in response to the gas turbine exhaust stream.   
   
   
       94 . The method of  claim 93 , wherein the formation hydrocarbons in the organic-rich rock formation comprise heavy hydrocarbons. 
   
   
       95 . The method of  claim 93 , wherein the organic-rich rock formation is an oil shale formation. 
   
   
       96 . The method of  claim 95 , further comprising:
 f) passing at least a portion of the generated electricity from the first electrical generator to a heater, the heater providing at least a portion of the in situ organic-rich rock formation heating.   
   
   
       97 . The method of  claim 96 , wherein the heater is an electrical resistance heater located in the organic-rich rock formation. 
   
   
       98 . The method of  claim 95 , wherein the first gas stream is comprised primarily of C 1  and C 2  hydrocarbons on a molar basis. 
   
   
       99 . The method of  claim 95 , wherein the first gas stream has a CO 2  content that is greater than 20 mole percent. 
   
   
       100 . The method of  claim 95 , wherein the first gas stream has a lower heating value of less than 700 BTU/SCF. 
   
   
       101 . The method of  claim 100 , wherein the first gas stream has a lower heating value of greater than 150 BTU/SCF. 
   
   
       102 . The method of  claim 95 , wherein the first gas stream further comprises hydrogen gas, the amount of hydrogen gas in the first gas stream being greater than 50 percent of the hydrogen gas contained in the production fluid. 
   
   
       103 . The method of  claim 95 , further comprising:
 f) feeding the first gas turbine exhaust stream to a steam boiler, the first gas turbine exhaust stream thereby providing heat to the steam boiler, and   g) producing steam in the steam boiler.   h) feeding the steam to a steam turbine, wherein the steam turbine is configured to provide energy to a second electrical generator.   
   
   
       104 . The method of  claim 103 , wherein greater than 80 percent of the energy used to heat the organic-rich rock formation in situ is provided by electricity generated in the first electrical generator and the second electrical generator. 
   
   
       105 . The method of  claim 95 , wherein the step of heating the organic-rich rock formation in situ includes:
 i) heating a first portion of the organic-rich rock formation in situ commencing at a first time;   ii) heating a second portion of the organic-rich rock formation in situ commencing at a second different time.   
   
   
       106 . An in situ method of producing hydrocarbon fluids from an organic-rich rock formation, comprising:
 a) heating an organic-rich rock formation in situ;   b) producing a production fluid from the organic-rich rock formation, the production fluid having been at least partially generated as a result of pyrolysis of formation hydrocarbons located in the organic-rich rock formation, the production fluid comprising hydrocarbon fluids;   c) separating the production fluid into at least a first gas stream and a first liquid stream, wherein the first gas stream comprises greater than 5 mole percent hydrocarbon gas and has a heating value of between 200 BTU/SCF and 800 BTU/SCF;   d) passing the first gas stream through a first gas turbine to form a first gas turbine exhaust stream, the first gas turbine being configured to provide energy to a first electrical generator; and   e) generating electricity in the first electrical generator in response to the gas turbine exhaust stream.   
   
   
       107 . The method of  claim 106 , wherein the formation hydrocarbons in the organic-rich rock formation comprise heavy hydrocarbons. 
   
   
       108 . The method of  claim 106 , wherein the organic-rich rock formation is an oil shale formation. 
   
   
       109 . The method of  claim 108 , further comprising:
 f) passing at least a portion of the generated electricity from the first electrical generator to an electrical resistance heater located in the organic-rich rock formation, the heater providing at least a portion of the in situ organic-rich rock formation heating.   
   
   
       110 . The method of  claim 108 , wherein the first gas stream is comprised primarily of C 1  and C 2  hydrocarbons on a molar basis. 
   
   
       111 . The method of  claim 108  wherein the first gas stream has a CO 2  content that is greater than 20 mole percent.