Systems and methods for optimizing formation fracturing operations
Systems and methods generate optimized formation fracturing operational parameters by iteratively optimizing bottom hole temperature design, perforation design, fracturing fluid pulse design, and proppant design based on formation properties, proppant properties, candidate selection, flow and geomechanical modeling, and engineering design, where the systems and methods as implemented on a digital processing unit.
1. A method of optimizing proppant placement in a subterranean formation; comprising the steps of:
(a) obtaining:
(1) formation, site and well properties and characteristics including formation depth, formation pore pressure gradient, formation temperature, formation natural fractures, formation cohesion, formation friction angle, formation anisotropy, formation zones, formation shale play zones, formation permeability, formation porosity, formation Young's modulus, formation Poisson's ratio, and formation effective stress,
(2) proppant properties and characteristics including type, zeta potential, coating type, diameter, and strength, and
(3) fracturing fluid properties and characteristics including base fluid type, viscosity, elasticity, proppant density, proppant diameter, proppant concentration, aggregating composition type, aggregating composition concentration, coating crosslinking composition concentration type, and coating crosslinking composition concentration;
(b) generating response surfaces for different proppant island and flow channel configurations based on the obtained properties and characteristics, a bottom hole pressure (BHP) design, a perforation design, a fracturing fluid rate and pulse design, and a proppant design;
(c) simulating island transport properties based on the obtained properties and characteristics, the BHP design, the perforation design, the fracturing fluid rate and pulse design, and the proppant design;
(d) simulating island embedment and fracture closure properties based on the obtained properties and characteristics, the BHP design, the perforation design, and the fracturing fluid rate and pulse design;
(e) generating fracturing operational parameters based on the simulated island transport properties and the simulated island embedment and fracture closure properties to determine flow channels and fracture lengths;
(f) adjusting the BHP design, the perforation design, and the fracturing fluid rate and pulse design;
(g) repeating steps (e) through (f), until the generated fracturing operational parameters are optimized to generate optimized fracturing operational parameters that are designed to produce an optimized proppant island and flow channel configuration;
wherein:
the optimized perforation design includes perforation hole diameter, perforation hole density, perforation length, perforation spacing, and total perforation length,
the optimized fracturing fluid rate and pulse design includes a series of proppant-free fracturing fluid pulses and proppant-containing fluid pulses, inlet velocities, pulse rates, pulse frequencies, and pulse intervals,
the optimized BHP design includes bottom hole pressure and temperature,
at least one of the fracturing fluids includes an aggregating composition comprising: 1) an amine/phosphate reaction product, 2) an amine component and an amine/phosphate reaction product, 3) a polymeric amine; 4) a polymeric amine and an amine/phosphate reaction products, 5) a polymeric amine, an amine component, and an amine/phosphate reaction product, 6) an amine component, 7) a coacervate aggregating composition, or 8) mixtures and combinations thereof,
at least one of the fracturing fluids includes a coating crosslinking composition comprising inorganic crosslinking agents, organic crosslinking agents, or mixtures and combinations thereof,
at least one of the fracturing fluid types include proppants,
the aggregating composition forms a coating on the proppant causing the coated proppant to aggregate into pillars in the fractures in accord with the proppant island and flow channel configuration, and
the coating crosslinking composition forms crosslinks in the coating stabilizing and strengthening the pillars within the proppant island and flow channel configuration.
2. The method of claim 1 , further comprising:
(h) transmitting the optimized fracturing operational parameters to a field location for implementation;
(i) fracturing the formation utilizing the optimized fracturing operational parameters;
(j) collecting near real time data while fracturing; and
(k) adjusting one, some or all of the optimized fracturing operational parameters while fracturing.
3. A system for fracturing a subterranean formation comprising:
a fracturing parameter generation subsystem implemented on a digital and/or analog processing unit that:
(a) obtains:
(1) formation, site and well properties and characteristics including formation depth, formation pore pressure gradient, formation temperature, formation natural fractures, formation cohesion, formation friction angle, formation anisotropy, formation zones, formation shale play zones, formation permeability, formation porosity, formation Young's modulus, formation Poisson's ratio, and formation effective stress,
(2) proppant properties and characteristics including type, zeta potential, coating type, diameter, and strength,
(3) fracturing fluid properties and characteristics including base fluid type, viscosity, elasticity, proppant density, proppant diameter, proppant concentration, aggregating composition type, aggregating composition concentration, coating crosslinking composition concentration type, and coating crosslinking composition concentration;
(b) generates response surfaces for different proppant island and flow channel configurations based on the obtained properties and characteristics, a bottom hole pressure (BHP) design, a perforation design, and a fracturing fluid rate and pulse design;
(c) simulates island transport properties based on the obtained properties and characteristics, the BHP design, the perforation design, and the fracturing fluid rate and pulse design;
(d) simulates island embedment and fracture closure properties based on the obtained properties and characteristics, the BHP design, the perforation design, and the fracturing fluid rate and pulse design;
(e) generates fracturing operational parameters based on the simulated island transport properties and the simulated island embedment and fracture closure properties to determine flow channels and fracture lengths;
(f) adjusts the BHP design, the perforation design, and the fracturing fluid rate and pulse design;
(g) repeats steps (e) through (f), until the generated fracturing operational parameters are optimized to produce optimized fracturing operational parameters,
wherein:
the optimized perforation design includes perforation hole diameter, perforation hole density, perforation length, perforation spacing, and total perforation length,
the optimized fracturing fluid rate and pulse design includes a series of proppant-free fracturing fluid pulses and proppant-containing fluid pulses, inlet velocities, pulse rates, pulse frequencies, and pulse intervals,
the optimized BHP design includes bottom hole pressure and temperature,
at least one of the fracturing fluids includes an aggregating composition comprising: 1) an amine/phosphate reaction product, 2) an amine component and an amine/phosphate reaction product, 3) a polymeric amine; 4) a polymeric amine and an amine/phosphate reaction products, 5) a polymeric amine, an amine component, and an amine/phosphate reaction product, 6) an amine component, 7) a coacervate aggregating composition, or 8) mixtures and combinations thereof,
at least one of the fracturing fluids includes a coating crosslinking composition comprising inorganic crosslinking agents, organic crosslinking agents, or mixtures and combinations thereof,
the aggregating composition forms a coating on the proppant causing the coated proppant to aggregate into pillars in the fractures in accord with the proppant island and flow channel configuration, and
the coating crosslinking composition forms crosslinks in the coating stabilizing and strengthening the pillars within the proppant island and flow channel configuration;
a delivery subsystem that fractures the formation according to the optimized formation fracturing parameters produces an optimized proppant island and flow channel configuration, and
a control subsystem in communication with the fracturing parameter generation subsystem and the delivery subsystem that receives the optimized formation fracturing parameters form the fracturing parameter generation subsystem, transmits the parameters to the delivery subsystem, and controls the delivery subsystem during formation fracturing.
4. The system of claim 3 , further comprising:
a sensor subsystem including a plurality of sensors that measure one, some or all of the fracturing operational parameter in real-time or near real time,
a parameter adjustment subsystem that receives sensor data and modifies or adjusts one, some, or all of the optimized formation fracturing parameters based on the received sensor data,
wherein the sensor subsystem and the parameter adjustment subsystem are in communication with the control subsystem and the control subsystem transmits the adjusted parameters to the delivery subsystem while fracturing.
5. The system of claim 3 , wherein the delivery subsystem comprises a pump.
6. The system of claim 5 , wherein the delivery subsystem further comprises a mixer.
7. The system of claim 5 , wherein the delivery subsystem further comprises a blender.
8. The system of claim 7 , wherein the blender comprises a programmable optimum density (POD) blender.
9. The system of claim 7 , wherein the blender comprises a tub blender.
10. The system of claim 4 , wherein the sensor is selected from the group consisting of pressure sensor, seismic sensor, tilt sensor, radioactivity sensor, magnetic sensor and electromagnetic sensor.
11. The system of claim 4 , wherein the sensor comprises an array of sensors.
12. The system of claim 4 , wherein the sensor comprises a noisy particulate material and a noisy particulate material sensor that detects a detonation, ignition or exothermic reaction of the noisy particulate material.
13. The system of claim 12 , wherein the noisy particulate material sensor includes a transmitting device that actively transmits location data and the sensor subsystem comprises a sensor for receiving the transmitted location data.
14. The method of claim 1 , wherein the optimized proppant island and flow channel configuration produces high conductivity fractures.
15. The method of claim 14 , wherein the optimized proppant island and flow channel configuration comprises an elongated island and flow channel structure comprising a central proppant pillar, a plurality of radially elongated proppant pillars, elongated boundary pillars, and elongated flow paths interposed between the pillars.
16. The method of claim 15 , wherein the pillars comprise crosslinked, aggregating composition coated proppant having improved crush strength, wherein the aggregating composition has a Zeta potential between −10 mV and −15 mV, between −5 mV and −10 mV, or between +3 mV and −5 mV.
17. The system of claim 3 , wherein the optimized proppant island and flow channel configuration produces high conductivity fractures.
18. The system of claim 17 , wherein the optimized proppant island and flow channel configuration comprises an elongated island and flow channel structure comprising a central proppant pillar, a plurality of radially elongated proppant pillars, elongated boundary pillars, and elongated flow paths interposed between the pillars.
19. The system of claim 18 , wherein the pillars comprise crosslinked, aggregating composition coated proppant having improved crush strength, wherein the aggregating composition has a Zeta potential between −10 mV and −15 mV, between −5 mV and −10 mV, or between +3 mV and −5 mV.