Methods and systems for monitoring well integrity and increasing the lifetime of a well in a subterranean formation

Abstract

A system for increasing the detecting degradation of a wellbore. The system comprises a computer memory configured for storing computing instructions and a processor operably coupled to the computer memory. The system comprises a sensor operably coupled to the computer memory and is configured to determine the presence of at least one chemical species indicative of degradation of the wellbore in a fluid exiting the wellbore. Methods of monitoring a wellbore for corrosion or other degradation of one or more components of wellbore equipment are disclosed as are methods of increasing the lifetime of a wellbore.

What is claimed is: 
     
         1 . A method of monitoring degradation of a wellbore, the method comprising:
 predicting at least one reaction between at least one of a formation fluid, a drilling fluid, a stimulation fluid, a completion fluid, an injected fluid, a component of wellbore equipment, a formation, and another of the formation fluid, the drilling fluid, the stimulation fluid, the completion fluid, the injected fluid, the component of wellbore equipment, and the formation using at least one of thermodynamic equations and chemical reaction kinetics equations;   identifying at least one property of a fluid exiting the wellbore, wherein the at least one property is indicative of the at least one reaction; and   analyzing the fluid exiting the wellbore for changes in the at least one property.   
     
     
         2 . The method of  claim 1 , further comprising determining a composition of at least one of the formation fluid, the drilling fluid, the stimulation fluid, the completion fluid, the injected fluid, the component of wellbore equipment, and the formation and predicting the at least one reaction using the composition of the at least one of the formation fluid, the drilling fluid, the stimulation fluid, the completion fluid, the injected fluid, the component of wellbore equipment, and the formation. 
     
     
         3 . The method of  claim 2 , wherein determining a composition of at least one of the formation and the formation fluid comprises at least one of wellbore logging the formation and sampling the at least one of the formation and the formation fluid to determine a property indicative of a concentration of at least one chemical species within the at least one of the formation and the formation fluid. 
     
     
         4 . The method of  claim 1 , wherein predicting at least one reaction using at least one of thermodynamic equations and chemical reaction kinetics equations comprises predicting the at least one reaction employing at least one of a subsurface temperature and a subsurface pressure. 
     
     
         5 . The method of  claim 4 , wherein the at least one of a subsurface temperature and a subsurface pressure is measured with a sensor. 
     
     
         6 . The method of  claim 4 , wherein predicting the at least one reaction employing at least one of a subsurface temperature and a subsurface pressure comprises predicting the at least one reaction with at least one of a predicted temperature and a predicted pressure within the wellbore. 
     
     
         7 . The method of  claim 1 , wherein analyzing the fluid exiting the wellbore for changes in the at least one property comprises analyzing the fluid within the wellbore or analyzing a sample of the fluid outside the wellbore. 
     
     
         8 . The method of  claim 1 , wherein identifying at least one property of a fluid exiting the wellbore comprises identifying a concentration of one or more ions, elements, compounds, molecules, substances, or materials that are indicative of the at least one reaction. 
     
     
         9 . The method of  claim 1 , wherein analyzing the fluid exiting the wellbore for changes in the at least one property comprises analyzing the fluid exiting the wellbore for changes in a concentration of at least one of iron, chromium, nickel, magnesium, cobalt, lead, manganese, copper, and titanium. 
     
     
         10 . The method of  claim 1 , wherein analyzing the fluid exiting the wellbore for changes in the at least one property comprises analyzing the fluid exiting the wellbore for changes in at least one of strontium and lithium. 
     
     
         11 . The method of  claim 1 , wherein analyzing the fluid exiting the wellbore for changes in the at least one property comprises analyzing the fluid for changes in a concentration of an elastomer. 
     
     
         12 . The method of  claim 1 , wherein analyzing the fluid exiting the wellbore for changes in the at least one property comprises analyzing the fluid exiting the wellbore for changes in at least one of a pH, a redox potential, a resistivity, a conductivity, and a salinity of the fluid. 
     
     
         13 . The method of  claim 1 , further comprising:
 forming at least a portion of the wellbore equipment from a material comprising a plurality of layers, forming the at least a portion of the wellbore equipment comprising:   forming an exposed first portion comprising a first material; and   forming an initially unexposed second portion comprising a second material.   
     
     
         14 . The method of  claim 13 , wherein analyzing the fluid exiting the wellbore for changes in the at least one property comprises analyzing the fluid exiting the wellbore for changes a concentration of at least one of the first material and the second material. 
     
     
         15 . The method of  claim 13 , wherein:
 forming an exposed portion comprising a first material comprises forming an exposed first layer comprising the first material; and   forming an initially unexposed second portion comprises forming an initially unexposed second layer comprising the second material.   
     
     
         16 . The method of  claim 1 , wherein analyzing the fluid exiting the wellbore for changes in the at least one property comprises adding a dye to a fluid entering the wellbore and monitoring the fluorescence of the fluid exiting the wellbore. 
     
     
         17 . A method of reducing degradation of a wellbore, the method comprising:
 determining a composition of at least one of a formation and a formation fluid within a wellbore;   predicting at least one reaction between the formation fluid and at least one of wellbore equipment, the formation, a drilling fluid, a stimulation fluid, an injected fluid, and a completion fluid;   identifying at least one chemical species in the fluid exiting the wellbore, wherein the at least one chemical species is indicative of the at least one predicted reaction; and   adjusting a composition of the injected fluid into the wellbore responsive to detection of the at least one chemical species indicative of the at least one predicted reaction in the fluid exiting the wellbore.   
     
     
         18 . The method of  claim 17 , wherein adjusting a composition of the injected fluid comprises increasing a concentration of at least one of a corrosion inhibitor, an oxygen scavenger, and an H 2 S scavenger in the injected fluid. 
     
     
         19 . The method of  claim 18 , further comprising determining a concentration of the at least one of the corrosion inhibitor, the oxygen scavenger, and the H 2 S scavenger in a produced fluid exiting the wellbore. 
     
     
         20 . A system for detecting degradation of wellbore equipment within a wellbore, the system comprising:
 a computing system comprising:
 a computer memory configured for storing computing instructions; and 
 a processor operably coupled to the computer memory and configured for retrieving the computing instructions from the computing memory and executing the computing instructions to predict a composition of a subsurface formation fluid and at least one reaction between the subsurface formation fluid and at least one of a drilling fluid, a stimulation fluid, a completion fluid, an injected fluid, and at least one component of wellbore equipment; and 
   a sensor operably coupled to the computing system, the sensor located and configured to detect at least one property of a produced fluid, wherein the at least one property is indicative of the at least one reaction.