Automated PVT Characterization and Flow Metering

Abstract

A pressure-volume-temperature (PVT) modeling system includes a sensing device configured to obtain a fluid measurement of a production fluid in a downhole portion of a well system or in a surface portion of the well system, and a processor comprising a PVT model builder, the processor configured to receive the fluid measurement from the sensing device, apply the fluid measurement as an input into the PVT model builder, and generate a PVT model.

We claim: 
     
         1 . A pressure-volume-temperature (PVT) modeling system for modeling production fluid from a well system, comprising:
 a sensing device configured to obtain a measurement of a condition of the production fluid in a downhole portion or in a surface portion of the well system; and   a processor configured to receive the measurement from the sensing device, apply the fluid measurement as an input into a PVT model builder, and generate a PVT model.   
     
     
         2 . The PVT modeling system of  claim 1 , wherein the measurement of a condition of the fluid includes at least one of downhole flow rate, surface flow rate, downhole fluid temperature, surface fluid temperature, downhole fluid pressure, surface fluid pressure, gas rate, oil rate, water rate, gas gravity, water salinity, or any combination of such. 
     
     
         3 . The PVT modeling system of  claim 1 , wherein the PVT model builder includes a system of equations configured to use the fluid measurement and known parameters of the well system to solve for a set of PVT model parameters. 
     
     
         4 . The PVT modeling system of  claim 3 , wherein the PVT model is defined by the PVT parameters. 
     
     
         5 . The PVT modeling system of  claim 3 , wherein the PVT parameters include a solution gas ratio, a bubble point pressure, an oil formation volume factor, an oil viscosity, a gas viscosity, or any combination of such. 
     
     
         6 . The PVT modeling system of  claim 1 , wherein the PVT model is a black-oil PVT model. 
     
     
         7 . The PVT modeling system of  claim 1 , wherein the PVT model is a compositional PVT model. 
     
     
         8 . The PVT modeling system of  claim 1 , wherein the PVT model is updated when the fluid measurement changes. 
     
     
         9 . A method of generating a PVT model for a production fluid from a well system, comprising:
 receiving, from a sensing device, a measurement of a condition of the production fluid in a downhole portion or a surface portion of the well system; and   generating a PVT model from the measurement.   
     
     
         10 . The method of  claim 9 , further comprising:
 inputting the measurement into a PVT model builder;   
     
     
         11 . The method of  claim 10 , further comprising:
 determining a set of PVT parameters from the measurement; and   generating the PVT model of the production fluid using the PVT parameters.   
     
     
         12 . The method of  claim 9 , wherein the PVT model is a black-oil PVT model. 
     
     
         13 . The method of  claim 9 , wherein the PVT model is a compositional PVT model. 
     
     
         14 . The method of  claim 9 , wherein the measurement includes a downhole flow rate, a downhole fluid temperature, a downhole fluid pressure, or any combination of such received from a first sensing device disposed within the well. 
     
     
         15 . The method of  claim 9 , wherein the measurement includes at least one of surface flow rate, surface fluid temperature, surface fluid pressure, or any combination of such received from a second sensing device coupled to a surface pipeline. 
     
     
         16 . The method of  claim 10 , further comprising:
 inputting the measurement into a system of equations; and   solving the system of equations for the PVT parameters.   
     
     
         17 . The method of  claim 9 , wherein the PVT model is generated in quasi-real time upon receiving the measurement. 
     
     
         18 . The method of  claim 9 , comprising:
 updating the PVT model when the measurement changes, at predetermined times, or upon receiving a command.   
     
     
         19 . The method of  claim 11 , further comprising determining the set of PVT parameters from the measurements and at least one known parameter of the well system. 
     
     
         20 . The method of  claim 9 , wherein the measurement of a condition of the production fluid includes at least one of downhole flow rate, surface flow rate, downhole fluid temperature, surface fluid temperature, downhole fluid pressure, surface fluid pressure, gas rate, oil rate, water rate, gas gravity, water salinity, or any combination of such.