Dispersion of compounds for the stimulation of biogenic gas generation in deposits of carbonaceous material

Abstract

Methods of dispersing an activation agent, nutrient, or both to a carbonaceous material to stimulate production of a biogenic gas are described. The methods may include accessing a subterranean geologic formation containing the carbonaceous material, and supplying a mixture to the formation. The mixture may include an activation agent or nutrient mixed with a dispersed phase and a continuous phase. The method may also include contacting the carbonaceous material with the mixture, and distributing at least a portion of the activation agent or nutrient over and/or into the carbonaceous material from the dispersed phase. The production of biogenic gases is increased by microorganisms that are stimulated by the distributed activation agent or nutrient to convert a portion of the carbonaceous material into the biogenic gases.

What is claimed is: 
     
         1 . A method of dispersing an activation agent to a carbonaceous material to stimulate production of a biogenic gas, the method comprising:
 accessing a subterranean geologic formation containing the carbonaceous material;   supplying a mixture to the geologic formation, wherein the mixture comprises the activation agent mixed with a dispersed phase and a continuous phase;   contacting the carbonaceous material in the formation with the mixture, wherein the dispersed phase distributes at least a portion of the activation agent over and/or into the carbonaceous material; and   increasing the production of the biogenic gas from microorganisms stimulated by the distributed activation agent to convert a portion of the carbonaceous material into the biogenic gas.   
     
     
         2 . The method of  claim 1 , wherein the dispersed phase comprises a non-polar liquid and the continuous phase comprises water. 
     
     
         3 . The method of  claim 1 , wherein the mixture comprises a multiple emulsion comprising water-in-oil-in-water, and wherein the dispersed phase comprises a non-polar liquid surrounding an aqueous solution and the continuous phase comprises water. 
     
     
         4 . The method of  claim 3 , wherein the activation agent is present in the aqueous solution in the dispersed phase. 
     
     
         5 . The method of  claim 1 , wherein the activation agent comprises at least one compound selected from the group consisting of an acetate compound, a yeast extract, an algal extract, and a phosphorus compound. 
     
     
         6 . The method of  claim 1 , wherein the activation agent comprises an aromatic compound including an ether linked group. 
     
     
         7 . The method of  claim 1 , wherein the activation agent comprises an aromatic compound including an ester linked group. 
     
     
         8 . The method of  claim 1 , further comprising metabolizing the non-polar dispersed phase by the microorganisms, wherein the metabolizing produces an acetate compound. 
     
     
         9 . The method of  claim 1 , wherein the non-polar dispersed phase comprises a fatty acid. 
     
     
         10 . The method of  claim 1 , wherein the contacting the carbonaceous material with the emulsion disperses at least a portion of the activation agent over a greater area of the formation. 
     
     
         11 . The method of  claim 1 , wherein the non-polar dispersed phase allows the emulsion to travel over and/or into the carbonaceous material without being absorbed therein. 
     
     
         12 . The method of  claim 1 , wherein the activation agent comprises sodium phosphate, potassium phosphate, a phosphorus oxyacid, a salt of a phosphorus oxyacid, an alkali metal salt of acetic acid, or an alkali metal earth metal salt of acetic acid. 
     
     
         13 . A method of providing a nutrient to a carbonaceous material to stimulate production of a biogenic gas, the method comprising:
 accessing a geologic formation containing the carbonaceous material;   delivering to the geologic formation a mixture comprising a dispersed phase and a continuous phase, wherein the nutrient is incorporated into at least one of the phases;   contacting the carbonaceous material in the geologic formation with the mixture, wherein the nutrient becomes accessible to microorganisms; and   increasing the production of the biogenic gas by stimulating the microorganisms with the nutrient to convert a portion of the carbonaceous material into the biogenic gas.   
     
     
         14 . The method of  claim 13 , wherein the dispersed phase is homogenously distributed in the mixture. 
     
     
         15 . The method of  claim 13 , wherein the dispersed phase comprises a non-polar liquid surrounding an aqueous solution and the continuous phase comprises water. 
     
     
         16 . The method of  claim 13 , wherein at least a portion of the nutrient is located in the dispersed phase. 
     
     
         17 . The method of  claim 13 , wherein the continuous phase comprises an aqueous solution in which the nutrient is partially dissolved. 
     
     
         18 . The method of  claim 17 , wherein the microorganisms consume a portion of the nutrient that is not fully incorporated in the homogenous mixture. 
     
     
         19 . The method of  claim 15 , wherein microorganisms consume the non-polar dispersed phase as an additional nutrient source. 
     
     
         20 . The method of  claim 19 , wherein consuming the non-polar dispersed phase delays the consumption of a second portion of the nutrient incorporated in the liquid mixture. 
     
     
         21 . The method of  claim 14 , wherein the homogenous mixture is an emulsion. 
     
     
         22 . The method of  claim 21 , wherein the emulsion is a microemulsion, and wherein the emulsion further comprises a surfactant. 
     
     
         23 . The method of  claim 13 , wherein the nutrient comprises an aromatic compound including an ether linked group. 
     
     
         24 . The method of  claim 13 , wherein the nutrient comprises an aromatic compound including an ester linked group. 
     
     
         25 . The method of  claim 13 , wherein the nutrient comprises methanol, ethanol, n-propanol, n-butanol, 2,3butanediol, ethanolamine, 3,4,5-trimethoxybenzoate, syringate, vanillate, glycine, cysteine, formate, yeast extract, hydrogen, or carbon dioxide. 
     
     
         26 . A method of introducing multiple portions of a compound to microorganisms in a geologic formation, the method comprising:
 accessing a geologic formation that contains carbonaceous material;   supplying an emulsion to the formation, wherein the emulsion has a continuous phase and a dispersed phase, and wherein a first portion of the compound is incorporated into the continuous phase and a second portion of the compound is incorporated in the dispersed phase;   introducing the first portion of the compound in the continuous phase to the microorganisms when the emulsion contacts the microorganisms, and introducing the second portion of the compound after the microorganisms contact the dispersed phase;   wherein the compound stimulates the microorganism to covert the carbonaceous material to one or more biogenic gases.   
     
     
         27 . The method of  claim 26 , wherein the compound comprises an activation agent or a nutrient. 
     
     
         28 . The method of  claim 26 , wherein the compound is selected from the group consisting of methanol, ethanol, n-propanol, n-butanol, 2,3butanediol, ethanolamine, 3,4,5-trimethoxybenzoate, syringate, vanillate, glycine, cysteine, formate, yeast extract, hydrogen, carbon dioxide, sodium phosphate, potassium phosphate, a phosphorus oxyacid, a salt of a phosphorus oxyacid, an alkali metal salt of acetic acid, and an alkali metal earth metal salt of acetic acid. 
     
     
         29 . The method of  claim 26 , wherein the continuous phase comprises water and the dispersed phase comprises a non-polar liquid. 
     
     
         30 . The method of  claim 26 , wherein the biogenic gases comprise hydrogen (H 2 ) or methane (CH 4 ). 
     
     
         31 . The method of  claim 26 , wherein the microorganisms consume the dispersed phase as an additional nutrient source. 
     
     
         32 . The method of  claim 31 , wherein consuming the non-polar dispersed phase produces an acetate compound. 
     
     
         33 . The method of  claim 26 , wherein the dispersed phase comprises two or more phases. 
     
     
         34 . The method of  claim 33 , wherein the dispersed phase comprises a polar-phased droplet surrounded by a non-polar-phased droplet.