A gas assisted fluid injection system for stimulating fluid-porous media interaction under in-situ conditions

Abstract

The present disclosure provides a gas-assisted fluid injection system (1000) and a method for simulating fluid-porous media interactions under in-situ conditions of high pressure and temperature. The system (1000) comprises a core holder assembly (100) configured to house a porous media (101) sample and simulate subsurface conditions, a confining oil pump (102) to apply confining pressure, and an accumulator assembly (104) connected to a gas source and a vacuum pump (105) for fluid injection. The system (1000) is equipped with a plurality of sensors (110, 111, 112, 131, 123, 130, 138) for real-time monitoring of temperature and pressure at inlet and outlet locations. A flexible metal heater (103) maintains the porous media (101) at elevated temperatures. A data logging (115) and computing device (114) facilitates continuous data acquisition and flow rate calculation. Reference Figure: Figure 1

Description

FIELD OF INVENTION

[0001] The present disclosure, in general relates to a system used insubsurface fluid transport and porous media analysis, and more particularly to agas-assisted fluid injection system designed for fluid porous media interactionstudies under controlled temperature and pressure conditions.BACKGROUND OF THE INVENTION

[0002] In many engineering fields, especially those dealing withsubsurface processes such as geothermal energy, oil and gas extraction, andcarbon capture and storage (CCS / CCUS), understanding the interaction betweenfluids and porous media under varying temperature and pressure conditions iscrucial. Accurate simulations of these interactions are essential for optimizingenergy extraction, waste disposal, and environmental protection. However,existing fluid flow setup technologies have several limitations that hinder theirability to replicate real-world conditions effectively.

[0003] A major limitation of traditional systems is their bulky andexpensive equipment. These systems often rely on multiple syringe pumps orpressure-volume controllers (PVCs) for fluid injection, which require specializedcomponents and significant space for setup, maintenance, and calibration.Consequently, these systems are often cost-prohibitive, making them inaccessibleto smaller laboratories or research institutions with limited budgets.

[0004] Another limitation is the limited fluid handling capacity. Manysystems are designed for single-phase fluid injection (e.g., water or brine), butreal-world scenarios often involve multi-phase fluid interactions, such as gasliquidmixtures. For example, in enhanced oil recovery (EOR), CO₂ sequestration,and geothermal energy extraction, fluid phases interact within porous media.Traditional systems, restricted to liquid injections, fail to accurately simulate thesecomplex interactions, limiting their usefulness in such applications.

[0005] Additionally, existing setups often struggle with simulatingrealistic temperature and pressure conditions. While pressure control may beachievable, maintaining accurate temperature control is essential for manysubsurface processes. Geothermal energy, for example, requires fluids to beinjected at high temperatures. Many systems lack the necessary temperaturecontrol, making it difficult to replicate high-pressure, high-temperatureenvironments found in deep geological formations.

[0006] Most traditional setups also lack versatility in fluid injection,typically handling only one fluid at a time. In subsurface processes like gasassistedoil recovery or CO₂ storage, gas-liquid interactions need to be studiedunder variable pressures and temperatures. Traditional systems that only handlesingle-phase fluid injections cannot replicate these complex multi-phasedynamics. Additionally, they often lack flexibility to easily switch between fluidtypes or adjust fluid parameters, further limiting their ability to simulate diversereal-world conditions.

[0007] Size and portability constraints also pose challenges, as manysystems require large infrastructure and space, making them difficult toimplement in smaller laboratories. Furthermore, they demand constant supervisionand expertise to operate, which can be prohibitive for many researchenvironments. Smaller, portable systems offer more flexibility but often lack thecapability to handle high-pressure, high-temperature fluid interactions, limitingtheir application for more demanding conditions.

[0008] Another notable issue is the inadequate multi-componentmonitoring in existing systems. Effective analysis requires the simultaneoustracking of parameters such as pressure, temperature, fluid type, flow rate, andphase behaviour. However, many systems fail to provide accurate, real-timereadings of these parameters, making it difficult to gain a comprehensiveunderstanding of fluid-porous media interactions.

[0009] Furthermore, existing setups are often inflexible in handlingdifferent core sizes and materials, which limits their applicability in experimentsinvolving varying porous media. Adapting the system to accommodate differentcore configurations is typically time-consuming and reduces its overall versatility.

[0010] In the prior art of CN118655009A a device for simulating the gasadsorption on coal samples and study chemical modification and displacement isdisclosed. However, they are limited to lower pressure and temperature ranges,unsuitable for testing heavier rocks like sandstones and granites. Additionally,these systems require complex gas-liquid metering and chemical modificationsetups, which are not needed in the present invention.

[0011] In the prior art of CN118549316A a device for testing themigration of supercritical carbon dioxide used as a fracture propping agent isdisclosed. However, it requires an X-ray instrument and imaging device foroperation and cannot operate at high temperatures for liquid injection.

[0012] In the prior art of CN118518559A a device designed forpermeability measuring for coal rock samples is disclosed. However, it requires apower gas storage, injection tank, and gas pressure controller for operation.

[0013] Therefore, there is still a need in the art for a compact, costeffective,and versatile fluid injection system capable of accurately simulatingmulti-phase fluid interactions within porous media under high-pressure and hightemperatureconditions.OBJECT OF THE INVENTION

[0014] It is the primary object of the present disclosure to provide a gas25assisted fluid injection system for stimulating fluid porous media interaction underin-situ conditions.

[0015] It is another object of the present disclosure to provide a method forsimulating fluid-porous media interaction under in-situ conditions.SUMMARY OF THE INVENTION

[0016] In an aspect of the present disclosure, a gas-assisted fluid injectionsystem for stimulating fluid porous media interaction under in-situ conditions isdisclosed.

[0017] In an aspect of the present disclosure, the gas-assisted fluidinjection system comprises a core holder assembly that houses a porous media,wherein the core holder assembly is mounted on a housing using one or moreholding clamps and the core holder assembly is wrapped around in a flexiblemetal heater for heating a. A confining oil pump is operatively connected to thecore holder assembly to provide confining pressure within the assembly,simulating in situ geostatic conditions. An accumulator assembly is mounted on aside of the housing and is connected to a fluid reserve containing a working fluid,with fluid transfer facilitated by a vacuum pump. The accumulator assembly isfurther connected to at least one of a gas cylinder or an air compressor, whichinjects pressurized gas to drive the working fluid into the porous media throughthe core holder assembly and is collected at a fluid collector. A plurality ofsensors is positioned at the inlet and outlet sides of the core holder assembly forreal-time measurement of pressure and temperature at the respective sides.

[0018] In an aspect of the present disclosure, the plurality of sensors (110,111, 112, 131, 123, 130, 138) are connected to a computing device (114) througha data logger (115). The plurality of sensors (110, 111, 112, 131, 123, 130, 138) isselected from thermocouple, inlet and outlet pressure sensors, delta pressuresensor, back pressure sensor, and confining pressure sensor.

[0019] In an aspect of the present disclosure, the flexible metal heater(103) further is wrapped around in a flexible insulating jacket (117).

[0020] In an aspect of the present disclosure, the core holder assembly(100) is detachably connected to a cylindrical end flange at both the left and rightends through a plurality of screws. The left cylindrical end flange (121) comprisesan extended protrusion comprising a hexagonal nut and a threaded circularextension, positioned at the center for attaching a first fluid inlet pipe (119) to thecore holder assembly (100). The left cylindrical end flange (121) furthercomprises an opening comprising a hexagonal nut and a threaded circularextension, positioned at a distance from the extended protrusion for housing a ktypethermocouple. The right cylindrical end flange (122), comprises a hollowthreaded cavity at the center for connecting a hollow cylindrical threadedarrangement for holding the porous media (101) within the core holder assembly(100).

[0021] In an aspect of the present disclosure, a temperature sensor (123) ispositioned inside the hollow cylindrical threaded arrangement for measuring thetemperature of the porous media (101).

[0022] In an aspect of the present disclosure, the accumulator assemblycomprises a regulator knob for controlling the injection of a working fluid into theaccumulator assembly, a gas pressure valve attached at the top of the regulatorknob, directing an injected gas into the core holder assembly, a vacuum inlet pipe,and a protrusion having a hexagonal nut at a base, wherein the regulator knob isattached to the accumulator assembly (104) through the protrusion.

[0023] In an aspect of the present disclosure, the system comprises atemperature controller (127) integrally mounted within the housing for controllingthe temperature inside the core holder assembly (100).

[0024] In an aspect of the present disclosure, the housing comprises aconfining pressure gauge (128) for monitoring and controlling the pressure of theaccumulator assembly (104). Further the system comprises an inlet pressure gauge(130) for measuring and monitoring the pressure of the working fluid (107).

[0025] In an aspect of the present disclosure, the system comprises aplurality of valves comprising a back pressure valve (134), confining controlvalve (135), vacuum valve (136), liquid injection valve (137) and protectiongauge valve (138) for controlling a plurality of operations. The system furthercomprises a protection gauge (133).

[0026] In an aspect of the present disclosure, the porous media is selectedfrom one of a rock and concrete.

[0027] In an aspect of the present disclosure, the working fluid id selectedfrom one of a CO2, water, or any organic fluid.

[0028] In yet another embodiment, a method for simulating fluid-porousmedia interaction using the gas-assisted fluid injection system is disclosed. Themethod includes placing a porous media as a core component in the core holderassembly, supplying the working fluid into the accumulator assembly through asecond fluid inlet pipe by attaching the vacuum pumping of 1 / 2 hp to a vacuuminlet pipe, confining the pressure of the core holder assembly using the confiningoil pump, and injecting the working fluid through a first fluid inlet pipe into thecore holder assembly by injecting a gas into the accumulator assembly through agas cylinder. The method further includes measuring the inlet / outlet pressure andtemperature of the working fluid continuously during the process by the pluralityof sensors and calculating the flow rate of the produced fluid collected in a fluidcollector.

[0029] These and other objects, features, and advantages of the presentdisclosure will become apparent to those of ordinary skill in the art from a readingof the following detailed description.BRIEF DESCRIPTION OF DRAWINGS

[0030] The exemplary embodiments of the present disclosure have beendescribed with reference to the accompanying drawings below:

[0031] Figure 1 illustrates a schematic diagram of the gas-assisted fluidinjection system for stimulating fluid porous media interaction under in-situconditions, in accordance with the present disclosure.

[0032] Figure 2 illustrates a cross-sectional view of the core holderassembly in accordance with the present disclosure.

[0033] Figure 3 illustrates a cross-sectional view of the end flange of thecore holder assembly in accordance with another embodiment of the presentdisclosure.

[0034] Figure 4 (a) illustrates a side view of the left cylindrical end flangeof the core holder assembly in accordance with another embodiment of the presentdisclosure.

[0035] Figure 4 (b) illustrates a side view of the right cylindrical endflange of the core holder assembly in accordance with another embodiment of thepresent disclosure.

[0036] Figure 5 illustrates a cross-sectional view of the accumulatorassembly in accordance with another embodiment of the present disclosure.

[0037] Figure 6 illustrates another schematic diagram of the gas-assistedfluid injection system for stimulating fluid porous media interaction under in-situconditions in accordance with another embodiment of the present disclosure.

[0038] Figure 7 illustrates a flowchart depicting the method of simulatingfluid-porous media interaction under in situ conditions, in accordance with thepresent disclosure.

[0039] Figure 8, illustrates the tabular representation of the pressure, flowrate, and temperature readings obtained during the testing of rock cores at hightemperature and pressure, in accordance to an embodiment of the presentinvention.

[0040] Figure 9 illustrates a graphical representation of the variation ofmass flow per unit area as a function of pressure drop along the length of the rockcore as a function of (a) confining pressure and (b) temperature, in accordance toan embodiment of the present disclosure.DETAILED DESCRIPTION OF THE INVENTION

[0041] The invention will be described in detail below with reference tothe drawings and specific embodiments. This embodiment is implemented on thepremise of the technical solution of the present invention, and detailedimplementation manners and specific operation procedures are given, but thescope of protection of the present invention is not limited to the followingembodiments.

[0042] Referring to Figure 1, illustrates a schematic diagram of a gasassistedfluid injection system for stimulating fluid porous media interaction underin-situ conditions, in accordance with the present disclosure. The gas-assistedfluid injection system (1000) comprises multiple subsystems integrated tosimulate fluid flow through porous materials under controlled conditions ofpressure and temperature. The system enables fluid saturation, permeabilitytesting, heat transfer coefficient determination, long-term dissolution, andadsorption / desorption experiments in rock or other porous media.

[0043] The gas-assisted fluid injection system (1000) comprises a coreholder assembly (100) that houses a porous media (101), wherein the core holderassembly (100) is mounted on a housing using one or more holding clamps (141a,141b) and the core holder assembly (100) is wrapped around in a flexible metalheater (103) for heating the porous media (101). A confining oil pump (102) isoperatively connected to the core holder assembly (100) to provide confiningpressure within the core holder assembly (100), simulating in situ geostaticconditions. An accumulator assembly (104) is mounted on a side of the housingand is connected to a fluid reserve (106) containing a working fluid (107), withfluid transfer facilitated by a vacuum pump (105). The accumulator assembly(104) is further connected to at least one of a gas cylinder (108) or an aircompressor, which injects pressurized gas to drive the working fluid (107) into theporous media (101) through the core holder assembly (100) and is collected at afluid collector (109). A plurality of sensors (110, 111, 112, 131, 123, 130, 138) ispositioned at the inlet and outlet sides of the core holder assembly (100) for realtime measurement of pressure and temperature at the respective sides.

[0044] Referring to Figure 2, illustrates a cross-sectional view of the coreholder assembly (100), designed to simulate fluid flow through porous media(101) under in situ pressure and temperature conditions, in accordance withanother embodiment of the present disclosure. The core holder housing isfabricated from SS 304 stainless steel and has a total length of 208 mm, an outerdiameter of 88 mm, and a thickness of 14 mm, ensuring high mechanical strength,corrosion resistance, and thermal stability under high temperature (flexible metalheater 20 to 200 °C) and high pressure [100 to 10,000 psi (0.7 to 70 MPa)]conditions. The core holder assembly (100) comprises one or more detachablespacers for handling varied rock cores from 70 to 105 mm in length.

[0045] Referring to Figure 3, illustrates a cross-sectional view of the endflange of the core holder assembly (100) in accordance with another embodimentof the present disclosure. The core holder assembly (100) is detachably connectedto a cylindrical end flange (121, 122) at both the left and right ends through aplurality of screws. The cylindrical end flanges (121, 122) made of SS 316, eachmeasuring 120 mm in diameter and 20 mm in thickness. These cylindrical endflanges (121, 122) are secured to the housing using eight screws, spaced 45 mmfrom the center and 44.7 mm apart from each other center-to-center, ensuring aleak-proof and pressure-resistant connection. Further the end flanges (121, 122)comprises a vent for capturing the outlet gases that is used for subsequent analysisusing standard equipment such as gas chromatography, FTIR, and NMR coupledwith mass spectroscopy.

[0046] Referring to Figure 4 (a), illustrates a side view of the leftcylindrical end flange (121) of the core holder assembly (100) in accordance withanother embodiment of the present disclosure. The left cylindrical end flange(121) of the core holder assembly (100) features a central extended protrusion thatfacilitates the connection of the first fluid inlet pipe (119) to the core holderassembly (100). This extended protrusion includes a hexagonal nut with 8 mmside length and 4 mm thickness, and a threaded circular extension of 6 mmdiameter, allowing for secure attachment of the fluid injection line. Located 10mm away from this central extended protrusion is an additional opening similarlyfitted with a hexagonal nut and threaded circular extension, specifically designedto house a k-type thermocouple for monitoring the porous media (101)temperature during experiments.

[0047] Referring to Figure 4 (b), illustrates a side view of the rightcylindrical end flange (122) of the core holder assembly (100) in accordance withanother embodiment of the present disclosure. The right end flange (122), whilesimilar in its flange assembly, contains a central hollow threaded cavity of 40 mmdiameter and 20 mm thickness, into which a hollow cylindrical threaded end stemis inserted. This end stem, which secures the core in place and provides a passagefor the outlet fluid, is 90 mm long and 30 mm in diameter, and is fused at the topwith another cylindrical section of 65 mm diameter and 25 mm thickness, havingcrisscross threading for enhanced grip. A temperature sensor (123) is positionedinside the hollow cylindrical threaded arrangement for measuring the temperatureof the porous media (101).

[0048] In an embodiment of the present disclosure, the core holderassembly (100) is mounted on the housing using two aluminum-made holdingclamps (141a, 141b), each having dimensions of 170 mm x 150 mm x 25 mm.These holding clamps (141a, 141b) are fastened to the main body of the system(1000) using four SS 316 bolts of 10 mm diameter, providing strong mechanicalsupport and minimizing vibrations or displacement during operation.

[0049] In another embodiment, the core holder assembly (100) is wrappedaround in the flexible metal heater (103) with an inner diameter of 90 mm andthickness of 10 mm, capable of delivering uniform heating from 20 to 200 °C witha power rating of 500 Watts. A heater temperature sensor (139) is connected tothe flexible metal heater (103) to monitor and regulate the heater's performance,while a heater outlet (140) is connected to the heater to enable electrical powersupply. The core holder assembly (100) further comprises a plurality of rubbersleeves (116) for holding the porous media (101); these sleeves are made of vitonrubber, which offers high resistance to temperatures from 20 to 200 °C andpressures from 100 to 7000 psi [0.7 to 50 MPa], ensuring structural integrity andsealing under extreme test conditions. A flexible insulating jacket (117) of 20 mmthickness is wrapped around the heater to minimize heat dissipation into theatmosphere and maintain thermal efficiency. The entire core holder assembly isthus a compact, modular unit that ensures precise fluid injection, secure sensorplacement, and controlled heating, all essential for simulating subsurfaceconditions accurately in fluid-porous media interaction studies. The system (1000)comprises a temperature controller (127) integrally mounted on the housing forcontrolling the temperature inside the core holder assembly (100).

[0050] In another embodiment, the confining oil pump (102) is acylindrical unit of total length 425 mm and diameter 80 mm, securely mounted tothe pedestal on the right side of the main body. The pump features an adjustablehandle of 25 mm thickness positioned at the top, enabling manual adjustment ofconfining pressure. At the far end of the pump, a control key is provided toselectively generate or release the confining pressure in the range of 100 to 10,000Psi (0.7 to 70 MPa). This key is attached to a circular protrusion of 25 mmdiameter and 20 mm thickness, extending outward to a total length of 50 mm anda thickness of 7 mm. The confining oil pump (102) is operably connected to thecore holder assembly (100) and plays a crucial role in simulating in situ pressureconditions during the injection of a working fluid (107) into the porous media(101). This arrangement enables precise control over confinement, facilitatingrealistic simulation of subsurface conditions and supporting accurate analysis offluid-porous media interactions.

[0051] In another embodiment, the accumulator serves as a liquid reservoirfor the working fluid (107) and is essential for enabling controlled fluid injectioninto the porous media (101) housed in the core holder assembly (100). Theaccumulator assembly (104) is a cylindrical vessel with a total volume of 300 cc,made up of stainless steel (SS 304) with an overall length of 445 mm, an outerdiameter of 60 mm, and a wall thickness of 10 mm, providing robust structuralintegrity under pressurized conditions. Internally, the accumulator features anadjustable piston made of stainless steel SS 316 L, having a diameter of 38 mmand a thickness of 55 mm, which facilitates displacement of the working fluid.The vessel is equipped with connectors measuring 90 mm in length and 15 mm indiameter, reducers with a length of 30 mm and diameter of 38 mm, and endconnections of 60 mm length and 45 mm diameter, all fabricated from SS 304 fordurability and chemical resistance.

[0052] Referring to figure 5, the accumulator assembly (104) furtherincludes a protrusion at its base comprising a hexagonal nut with each sidemeasuring 15 mm and a thickness of 6 mm, onto which a threaded cylinder of 28mm diameter and 30 mm length is attached. This protrusion supports a regulatorknob, which has a diameter of 50 mm and a length of 40 mm, and is used tocontrol the injection of gas into the accumulator. Mounted on top of the regulatorknob is a gas pressure valve, having a length of 58 mm, an average width of 20mm, and a thickness of 11 mm, which allows redirection of the injected gasdirectly from the transfer vessel to the core holder assembly (100), enhancingoperational flexibility. The accumulator assembly (104) includes a vacuum inletpipe (124), through which a vacuum pump (105) draws the working fluid (107)from the fluid reserve (106) into the accumulator, the working fluid (107) in theaccumulator assembly (104) is pressurized by injecting a gas from the gascylinder (108) or air compressor, thereby injecting the working fluid (107) intothe porous media (101), the injected working fluid (107) passes through theporous media (101) and collected at a fluid collector (109).

[0053] In an embodiment of the present disclosure, the accumulatorassembly (104) is pressurized by injecting a gas from a nitrogen gas cylinderhaving a primary and secondary gauge of 2000 Psi and 1000 Psi, respectively oran air compressor generating air pressure of more than 1000 Psi.

[0054] Referring to Figure 6, the system (1000) further comprises acontrol panel display (129), a control and monitoring unit, positioned on the frontface of the housing and measures 110 mm in width and 65 mm in height criticalfor managing and observing experimental parameters during operation. Thedisplay (129) projects real-time readings of the inlet temperature, outlettemperature, and core (rock) temperature, as well as inlet (upstream) pressure,outlet (downstream) pressure, delta pressure, and back pressure during the testingof the porous media (101).

[0055] In another embodiment, to facilitate pressure monitoring, thesystem incorporates two precision mechanical gauges. A confining pressure gauge(128) with an outer diameter of 135 mm and inner diameter of 110 mm iscalibrated to measure pressures from 100 to 10,000 Psi [0.7 to 70 MPa]. An inletpressure gauge (130) is also included, featuring an outer diameter of 70 mm andinner diameter of 50 mm, capable of measuring pressures from 100 to 3000 Psi[0.7 to 20 MPa].

[0056] In another embodiment, to ensure complete operational control, thesystem is further equipped with plurality of valves, positioned on the front panelof the setup for controlling a plurality of operations. These include a back pressurevalve (134), confining control valve (135), vacuum valve (136), liquid injectionvalve (137), and protection gauge valve (138). Each valve measures 58 mm inlength, with an average width of 20 mm and a thickness of 11 mm, and is used toregulate the respective fluid or pressure operation during the injection process.These valves allow precise manipulation of system conditions, enablingsimulation of in situ reservoir environments with controlled variables.

[0057] In another embodiment, the system (1000) comprises the pluralityof sensor, employed to ensure real-time monitoring and precise control ofexperimental parameters during fluid-porous media interaction under in situconditions. These plurality of sensors are operatively connected to a computingdevice (114) through a data logger (115), facilitating continuous acquisition andlogging of temperature and pressure data throughout the injection process. Thesystem includes a first temperature sensor (110) positioned at the inlet side of thecore holder assembly (100) for measuring the inlet temperature of the workingfluid (107), and a second temperature sensor (111) located at the outlet side of thecore holder assembly (100) for determining the outlet temperature. Additionally, athird temperature sensor (123) is installed within a hollow cylindrical threadedarrangement inside the right cylindrical end flange (122) to accurately record theinternal temperature of the porous media (101), ensuring comprehensive thermalprofiling during testing. The system incorporates to monitor pressure variations,an inlet pressure sensor (112) for recording the injection pressure of the workingfluid (107), an inlet pressure gauge (130) for additional analog verification, and anoutlet pressure sensor (113) for measuring the fluid pressure exiting the porousmedia. A delta pressure sensor (131) is connected between the first fluid inlet pipe(119) and the second fluid outlet pipe (126) to measure the pressure differentialacross the porous media (101), which is critical for evaluating permeability andflow resistance. The second outlet pipe is 3.2 mm in diameter and is made ofPTFE (Teflon). A back pressure sensor (132) is positioned at the outlet side of thecore holder assembly to regulate and maintain back pressure within desired limitsduring the experiment. All temperature and pressure sensors may be selected fromthermocouples, resistive temperature detectors (RTDs), or strain-gauge basedpressure transducers, ensuring robust performance under high-pressure and hightemperatureconditions. The comprehensive integration of this sensor networkallows the system to accurately simulate subsurface conditions, assess fluidbehavior in porous structures, and deliver reliable experimental data with highprecision.

[0058] Referring to Figure 7, illustrates a flowchart depicting the methodof simulating fluid-porous media interaction under in situ conditions. The methodcomprising the steps of placing a porous media (101) as a core component inside acore holder assembly (100), supplying a working fluid (107) into an accumulatorassembly (104) through a second fluid inlet pipe (125) by attaching a vacuumpump (105) of 1 / 2 hp to a vacuum inlet pipe (124), confining the pressure of thecore holder assembly (100) through closing the key of a confining oil pump (102)by keeping the controlling confining valve (135) in the down direction and turningthe handle of the confining oil pump (102) up and down till the appropriateconfining pressure is achieved. Followed by injecting the working fluid (107)through a first fluid inlet pipe (119) into the core holder assembly (100) byinjecting a gas into the accumulator assembly (104) through a gas cylinder (108).The method further comprises the step of measuring the inlet and outlet pressureand temperature of the working fluid (107) continuously during the process by aplurality of sensors. The method further comprises the step of measuring the flowrate of the outlet working fluid (107) flowing into the fluid collector (109) bycalculating the time required for collecting a quantity of the working fluid (107) inthe fluid collector (109) using a computing device (114).

[0059] Working Examples: Simulating fluid-porous media interactionunder in-situ conditions [at high confining pressure (≈4000 Psi) and hightemperature (≈90 °C)]:

[0060] The Liquid permeability were determined based on Darcy's Law,which is given by:kL =14700 x Lqμ / A(P1 - P2)where: kL-liquid Permeability (mD); q- flowrate, (ml / s); μ- liquidviscosity, (cp); L-Core Length, (cm); A-cross-sectional area of the core sample,(cm2), P1 = upstream pressure, (Psi), P2 = Downstream pressure, (Psi).

[0061] The upstream (P1) and downstream (P2) pressures, confiningpressure (C), and rock temperature (T) were continuously monitored using thevarious pressure and temperature sensors installed in the gas-assisted fluidinjection system. The flow rate of the liquid coming out after passing through therock core was measured by noting the time taken to collect 1 mL of the extract ina measuring cylinder. Referring to Figure 8, illustrates the tabular representationof the pressure, flow rate, and temperature readings obtained during the testing ofrock cores at high temperature and pressure, in accordance to an embodiment ofthe present invention.

[0062] Referring to Figure 9, illustrates a graphical analysis of thevariation of mass flow per unit area as a function of pressure drop along the lengthof the rock core as a function of (a) confining pressure and (b) temperature, inaccordance to an embodiment of the present disclosure. In particular, figure 9illustrates a graphical representation between the flow rate per unit cross-sectionalarea of the rock core and the pressure difference per unit length of the sample. Theslop of the graph illustrated in figure 9, indicates the permeability of the rockcores. Further Figure 9 depicts the effect of confining pressure (varied in the rangeof 500 Psi to 4000 Psi) and rock temperature (varied in the range of 25 °C to 90°C) on the permeability of the rock cores. In can be observed from Figure 9 thatthat with the increase in confining pressure, there is a decrease in the permeabilitywhereas with the increase in the temperature, there is an increase in thepermeability of the rock sample.

[0063] The above description along with the accompanying drawings isintended to disclose and describe the preferred embodiments of the invention insufficient detail to enable those skilled in the art to practice the invention. Itshould not be interpreted as limiting the scope of the invention. Those skilled inthe art to which the invention relates will appreciate that many variations of theexemplary implementations and other implementations exist within the scope ofthe claimed invention. Various changes in the form and detail may be made therein without departing from its spirit and scope. Similarly, various aspects ofthe present invention may be advantageously practiced by incorporating all features or certain sub-combinations of the features.

Claims

1. A gas assisted fluid injection system (1000) for simulating fluid-porous media interaction under in situ conditions, comprising: a core holder assembly (100) comprising a porous media (101) as a core component, wherein the core holder assembly (100) is mounted on a housing through one or more holding clamps (141a, 141b); a confining oil pump (102) connected to the core holder assembly (100) for providing the confining pressure inside the core holder assembly (100); an accumulator assembly (104) mounted on a side of the housing; a fluid reserve (106) comprising a working fluid (107), connected to the accumulator assembly (104) via a vacuum pump (105); at least one of: a gas cylinder (108) or an air compressor connected to the accumulator assembly (104); and a plurality of sensors (110, 111, 112, 131, 123, 130, 138) positioned at an inlet side and an outlet side of the core holder assembly (100) for measuring the temperature and pressure at the respective sides; wherein the core holder assembly (100) is wrapped around in a flexible metal heater (103) for heating the porous media (101); wherein the working fluid (107) is filled inside the accumulator assembly (104) from the fluid reserve (106) via the vacuum pump (105), the working fluid (107) in the accumulator assembly (104) is pressurized by injecting a gas from the gas cylinder (108) or air compressor, thereby injecting the working fluid (107) into the porous media (101), the injected working fluid (107) passes through the porous media (101) and collected at a fluid collector (109).

2. The gas assisted fluid injection system as claimed in 1, wherein the plurality of sensors (110, 111, 112, 131, 123, 130, 138) are connected to a computing device (114) through a data logger (115).

3. The gas assisted fluid injection system as claimed in claim 1, wherein the flexible metal heater (103) further is wrapped around in a flexible insulating jacket (117).

4. The gas assisted fluid injection system as claimed in claim 1, wherein the core holder assembly (100) is detachably connected to a cylindrical end flange at both the left and right ends through a plurality of screws.

5. The gas assisted fluid injection system as claimed in claim 4, wherein the left cylindrical end flange (121) comprises an extended protrusion comprising a hexagonal nut and a threaded circular extension, positioned at the center for attaching a first fluid inlet pipe (119) to the core holder assembly (100).

6. The gas assisted fluid injection system as claimed in claim 4, wherein the left cylindrical end flange (121) further comprises an opening comprising a hexagonal nut and a threaded circular extension, positioned at a distance from the extended protrusion for housing a k-type thermocouple.

7. The gas assisted fluid injection system as claimed in claim 4, wherein the right cylindrical end flange (122), comprises a hollow threaded cavity at the center for connecting a hollow cylindrical threaded arrangement for holding the porous media (101) within the core holder assembly (100).

8. The gas assisted fluid injection system as claimed in 7, wherein a temperature sensor (123) is positioned inside the hollow cylindrical threaded arrangement for measuring the temperature of the porous media (101).

9. The gas assisted fluid injection system as claimed in 1, wherein the accumulator assembly (104) comprises a regulator knob for controlling the injection of a working fluid into the accumulator assembly; a gas pressure valve attached at the top of the regulator knob, directing an injected gas into the core holder assembly; a vacuum inlet pipe (124); and a protrusion having a hexagonal nut at a base, wherein the regulator knob is attached to the accumulator assembly (104) through the protrusion.

10. The gas assisted fluid injection system as claimed in claim 1, wherein the system comprises a temperature controller (127) integrally mounted within the housing for controlling the temperature inside the core holder assembly (100).

11. The gas assisted fluid injection system as claimed in claim 1, wherein the housing comprises a confining pressure gauge (128) for monitoring and controlling the pressure of the accumulator assembly (104).

12. The gas assisted fluid injection system as claimed in claim 1, wherein the system comprises an inlet pressure gauge (130) for measuring and monitoring the pressure of the working fluid (107).

13. The gas assisted fluid injection system as claimed in claim 1, wherein the plurality of sensors (110, 111, 112, 131, 123, 130, 138) is selected from thermocouple, inlet and outlet pressure sensors, delta pressure sensor, back pressure sensor, and confining pressure sensor.

14. The gas assisted fluid injection system as claimed in claim 1, wherein the system comprises a plurality of valves comprising a back pressure valve (134), confining control valve (135), vacuum valve (136), liquid injection valve (137) and protection gauge valve (138) for controlling a plurality of operations.

15. The gas assisted fluid injection system as claimed in claim 1, wherein the porous media (101) is selected from one of a rock, and concrete.

16. The gas assisted fluid injection system as claimed in claim 1, wherein the working fluid is selected from one of a CO2, water, or any other organic fluid.

17. A method of simulating fluid-porous media interaction under in situ conditions, the method comprising the steps of: placing a porous media (101) as a core component inside a core holder assembly (100); supplying a working fluid (107) into an accumulator assembly (104) through a second fluid inlet pipe (125) by attaching a vacuum pump (105) of 1 / 2 hp to a vacuum inlet pipe (124); confining the pressure of the core holder assembly (100) through a confining oil pump (102); and injecting the working fluid (107) through a first fluid inlet pipe (119) into the core holder assembly (100) by injecting a gas into the accumulator assembly (104) through a gas cylinder (108).

18. The method as claimed in claim 17, wherein the method comprises the step of measuring the inlet and outlet pressure and temperature of the working fluid (107) continuously during the process by a plurality of sensors (131, 110,111).

19. The method as claimed in claim 17, wherein the method comprises the step of measuring the flow rate of the outlet working fluid (107) flowing into the fluid collector (109) by calculating the time required for collecting a quantity of the working fluid (107) in the fluid collector (109) using a computing device (114).