CN119466604A - Oil pipe assembly for gas well and gas well hydrate prevention and control method - Google Patents
Oil pipe assembly for gas well and gas well hydrate prevention and control method Download PDFInfo
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- CN119466604A CN119466604A CN202311001412.2A CN202311001412A CN119466604A CN 119466604 A CN119466604 A CN 119466604A CN 202311001412 A CN202311001412 A CN 202311001412A CN 119466604 A CN119466604 A CN 119466604A
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/02—Couplings; joints
- E21B17/04—Couplings; joints between rod or the like and bit or between rod and rod or the like
- E21B17/042—Threaded
- E21B17/0426—Threaded with a threaded cylindrical portion, e.g. for percussion rods
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B19/00—Handling rods, casings, tubes or the like outside the borehole, e.g. in the derrick; Apparatus for feeding the rods or cables
- E21B19/08—Apparatus for feeding the rods or cables; Apparatus for increasing or decreasing the pressure on the drilling tool; Apparatus for counterbalancing the weight of the rods
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B36/00—Heating, cooling or insulating arrangements for boreholes or wells, e.g. for use in permafrost zones
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- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Mechanical Engineering (AREA)
- Filling Or Discharging Of Gas Storage Vessels (AREA)
- Thermal Insulation (AREA)
Abstract
The invention discloses an oil pipe assembly for a gas well, which comprises a lifting mechanism, a heat preservation oil pipe and a penetrating oil pipe, wherein the lifting mechanism is connected with a fixed oil pipe, the fixed oil pipe is vertically arranged, the lifting mechanism can enable the fixed oil pipe to lift along the axial direction, the fixed oil pipe is provided with a safety valve, the heat preservation oil pipe is coaxially and detachably connected with the fixed oil pipe, the heat preservation oil pipe is coated with a heat preservation sleeve, and the penetrating oil pipe is coaxially and detachably connected with one end of the heat preservation oil pipe, which is far away from the fixed oil pipe. The water jacket furnace ground heating and hydrate inhibitor adding device can replace two measures, and solves various problems caused by water jacket furnace ground heating and hydrate inhibitor adding on the premise of ensuring that hydrate is not generated after throttling. The gas well hydrate control method can solve the problem of hydrate generation after surface throttling.
Description
Technical Field
The invention relates to the technical field of oil production engineering in the petroleum industry, in particular to an oil pipe assembly for a gas well and a gas well hydrate control method.
Background
In the production process of the natural gas well, because the wellhead pressure is high, the wellhead pressure needs to be reduced to the output pressure through throttling, the natural gas temperature is suddenly reduced due to the fact that the throttling generates a sharp pressure drop, if the throttled temperature is lower than the hydrate generation temperature corresponding to the throttled pressure, hydrates are generated, a shaft and a ground gas production pipeline are blocked, and normal production of the gas well is affected.
Production sites typically employ water jacket furnace surface heating, hydrate inhibitor injection or downhole throttling depressurization to prevent hydrate formation. The essence of the water jacket furnace ground heating is that the temperature of the air flow is increased to be higher than the temperature for generating hydrate, and the air flow is indirectly heated by taking water and steam as heat transfer media; hydrate inhibitors are added to lower the dew point of natural gas so that the gas stream does not form hydrates at lower temperatures. The antifreezing agent is various, such as methanol, glycol, diethylene glycol, calcium chloride aqueous solution and the like, and glycol is commonly used in gas production, so that a large amount of hydrate generation and aggregation are effectively inhibited under low dosage, but the problems of complex treatment process, high cost, environmental protection and the like of the alcohol-containing sewage exist. The underground throttling technology adopts rope operation to sit down an underground throttle at a proper position of a shaft, realizes throttling and depressurization of fluid in the shaft through a throttle nozzle, thereby reducing the pressure of the shaft mouth, absorbing formation heat by the throttled fluid, leading the temperature of the throttled fluid to be higher than the hydrate generation temperature, preventing the generation of hydrate.
Disclosure of Invention
The first object of the invention is to provide an oil pipe assembly for a gas well, which can replace two measures of water jacket furnace ground heating and hydrate inhibitor adding, and solve various problems caused by water jacket furnace ground heating and hydrate inhibitor adding on the premise that hydrate is not generated after throttling.
The second object of the invention is to provide a gas well hydrate control method which can solve the problem of hydrate generation after surface throttling.
The invention is realized by the following technical scheme:
The oil pipe assembly for the gas well comprises a lifting mechanism, a heat preservation oil pipe, a penetrating oil pipe and a penetrating oil pipe, wherein the lifting mechanism is connected with a fixed oil pipe, the fixed oil pipe is vertically arranged, the lifting mechanism can enable the fixed oil pipe to lift along the axial direction, the fixed oil pipe is provided with a safety valve, the heat preservation oil pipe is coaxially and detachably connected with the fixed oil pipe, the heat preservation oil pipe is coated with a heat preservation sleeve, and the penetrating oil pipe is coaxially and detachably connected with one end, far away from the fixed oil pipe, of the heat preservation oil pipe.
Optionally, the fixed oil pipe, the heat preservation oil pipe and the penetrating oil pipe are connected in a coaxial and detachable mode through threads.
Optionally, the heat preservation cover includes first half hoop, second half hoop and a plurality of mounting, first half hoop with second half hoop can hug and form the heat preservation cover, the mounting can maintain first half hoop with the state of hugging of second half hoop.
Optionally, the fixing piece is annular, and the fixing piece is sleeved outside the first half hoop and the second half hoop which are in hugging.
The insulation sleeve comprises a pair of fixing pieces, wherein the outer diameters of the two ends of the first anchor ear and the second anchor ear in the length direction are smaller than the outer diameter of the middle part, so that supporting edges are formed at the two ends respectively, the inner diameters of the fixing pieces are matched with and sleeved with the outer diameters of the two ends of the first anchor ear and the second anchor ear in the length direction, and the fixing pieces are attached to the supporting edges.
Optionally, the outer walls at the two ends of the first anchor ear and the second anchor ear in the length direction are provided with external threads, the corresponding ends of the fixed oil pipe and the penetrating oil pipe are provided with internal threads, and the fixing piece is clamped between the support edge and the corresponding ends of the fixed oil pipe or the penetrating oil pipe.
Optionally, an insulation layer is sandwiched between the insulation sleeve and the insulation oil pipe, the insulation layer is uniformly coated on the outer wall of the insulation oil pipe and compacted by the insulation sleeve, and the insulation layer is made of any one or more of aerogel felt, microporous calcium silicate, titanium ceramic insulation board, aluminum silicate fiber blanket, platy aerogel and aerogel coating.
A method for controlling gas well hydrates, comprising the steps of:
Obtaining the preset length of the thermal insulation oil pipe;
And (3) after the heat-insulating oil pipe of any one of the oil pipe assemblies for the gas well is lowered into the well for the preset length, performing ground throttling.
Optionally, the obtaining the preset length of the thermal insulation oil pipe includes the following steps:
establishing a shaft temperature-pressure coupling model;
obtaining the hydrate generation temperature after ground throttling and the wellhead temperature without generating hydrate according to the shaft temperature-pressure coupling model;
fitting any parameter of the oil pipe assembly for the gas well with a shaft temperature-pressure coupling model to obtain a thermal insulation oil pipe run-in length-wellhead temperature model;
and carrying the wellhead temperature which does not generate hydrate into a thermal insulation oil pipe run-in length-wellhead temperature model to obtain the preset length.
Optionally, the building of the wellbore temperature-pressure coupling model includes the steps of:
Establishing a calculation formula of the total heat transfer coefficient of the shaft:
The heat-insulating heat-conducting sleeve comprises a heat-conducting sleeve body, wherein U is the total heat-conducting coefficient of a shaft, R 1 is the heat-conducting heat resistance of a production fluid and the inner wall of the oil pipe, the unit is (m 2) DEG C/W, R 2 is the heat-conducting heat resistance of the oil pipe, the unit is (m 2) DEG C/W, R 3 is the heat-conducting heat resistance of an insulating layer, the unit is (m 2) DEG C/W, R 4 is the radiation heat-conducting heat resistance of an annular medium, the unit is (m 2) DEG C/W, R 5 is the heat-conducting heat resistance of the annular medium, the unit is (m 2) DEG C/W, R 6 is the heat-conducting heat resistance of a sleeve pipe, the unit is (m 2) DEG C/W, and R 7 is the heat-conducting heat resistance of a cement layer;
according to a calculation formula of the total heat transfer coefficient of the shaft, introducing the thermal physical property space distribution of the stratum, and establishing a shaft temperature-pressure coupling model, wherein the shaft temperature-pressure coupling model meets the following calculation formula:
The method comprises the steps of enabling theta to be included angle of a shaft and a horizontal plane, enabling dz to be a trace element body which is long along the shaft, enabling cp to be constant pressure specific heat capacity, enabling the cp to be the unit of J/(kg DEG C), enabling alpha v to be the volume expansion coefficient, enabling K -1;rins to be the outer diameter of an insulating layer, enabling G to be the unit of mass flow of produced liquid, enabling Te to be the original stratum temperature, enabling Ke to be the stratum heat conductivity coefficient of the place where the trace element section is located, enabling f (t D) to be the dimensionless temperature, enabling Tm to be the temperature of produced liquid in an oil pipe, enabling Ti to be the inner diameter of the oil pipe, enabling Km to be the heat conductivity coefficient of the produced liquid in the oil pipe, enabling v m to be the average flow rate of the produced liquid in the oil pipe, enabling lambda to be the darcy friction coefficient, and enabling ρm to be the average density of the produced liquid to be the unit of kg/m 3.
Compared with the prior art, the invention has the following advantages and beneficial effects:
The invention provides an oil pipe assembly for a gas well, which is characterized in that a heat preservation oil pipe is arranged, a heat preservation sleeve is coated on the heat preservation oil pipe to greatly reduce the heat conductivity coefficient of the heat preservation oil pipe, so that the heat loss of a shaft is reduced, the temperature of a well mouth is increased to be higher than the generation temperature of hydrate, the problem that the hydrate is generated after the ground of the gas well throttles and cools is solved, the heat preservation oil pipe assembly is detachably connected with the heat preservation oil pipe by arranging a fixed oil pipe, a connection foundation is provided for the heat preservation oil pipe, a lifting mechanism is further arranged to be connected with the fixed oil pipe, the heat preservation oil pipe can be indirectly driven to extend into the well by utilizing the lifting mechanism, the extending length of the heat preservation oil pipe is adjusted, and the temperature of the well mouth is adjusted. Through the mutual matching of the components, the oil pipe component for the gas well can solve the problem of hydrate generation after throttling, and can replace two measures of ground heating and hydrate inhibitor adding of a water jacket furnace, so that the problems of the two measures are directly avoided.
Drawings
The accompanying drawings, which are included to provide a further understanding of embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings:
FIG. 1 is a schematic illustration of an oil line assembly for a gas well provided in an embodiment of the present invention;
FIG. 2 is a side cross-sectional view of an oil line assembly for a gas well provided in an embodiment of the present invention;
FIG. 3 is a schematic illustration of an embodiment of the present invention providing an oil conduit assembly for a gas well in operation;
FIG. 4 is a flow chart of a method for controlling gas well hydrates provided by an embodiment of the present invention;
fig. 5 is a calculation flow chart of a simulated three-dimensional crack propagation model numerical solution program of the gas well hydrate control method provided by the embodiment of the invention;
FIG. 6 is a seepage model diagram of a fracture of a gas well hydrate control method provided by an embodiment of the invention;
FIG. 7 is a graph of a wellbore temperature-pressure coupling model for a gas well hydrate control method provided by an embodiment of the present invention;
fig. 8 is a thermal insulation tubing run-in length-wellhead temperature model diagram of a gas well hydrate control method provided by an embodiment of the invention.
In the drawings, the reference numerals and corresponding part names:
10-fixed oil pipe, 11-safety valve, 20-heat-insulating oil pipe, 21-heat-insulating sleeve, 211-first half hoop, 212-second half hoop, 213-fixing piece, 214-supporting edge, 22-heat-insulating layer and 30-penetrating oil pipe.
Detailed Description
For the purpose of making apparent the objects, technical solutions and advantages of the present invention, the present invention will be further described in detail with reference to the following examples and the accompanying drawings, wherein the exemplary embodiments of the present invention and the descriptions thereof are for illustrating the present invention only and are not to be construed as limiting the present invention.
Referring to fig. 1 to 3, the present embodiment provides an oil pipe assembly for a gas well, which comprises a lifting mechanism, wherein the lifting mechanism is connected with a fixed oil pipe 10, the fixed oil pipe 10 is vertically arranged, the lifting mechanism can enable the fixed oil pipe 10 to lift along an axial direction, the fixed oil pipe 10 is provided with a safety valve 11, the second oil pipe assembly comprises a heat preservation oil pipe 20, the heat preservation oil pipe 20 is coaxially and detachably connected with the fixed oil pipe 10, the heat preservation oil pipe 20 is coated with a heat preservation sleeve 21, and the third oil pipe assembly comprises a penetrating oil pipe 30, and the penetrating oil pipe 30 is coaxially and detachably connected with one end, far away from the fixed oil pipe 10, of the heat preservation oil pipe 20.
According to the oil pipe assembly for the gas well, the heat preservation oil pipe 20 is arranged, the heat preservation sleeve 21 is coated on the heat preservation oil pipe 20 to greatly reduce the heat conductivity coefficient of the heat preservation oil pipe, so that the heat loss of a shaft is reduced, the temperature of the shaft mouth is increased, the heat preservation oil pipe is higher than the generation temperature of hydrate, the problem that the hydrate is generated after the ground of the gas well throttles and cools is prevented, the heat preservation oil pipe assembly is detachably connected with the heat preservation oil pipe 20, a connection foundation is provided for the heat preservation oil pipe 20, the lifting mechanism is further arranged to be connected with the heat preservation oil pipe 10, the heat preservation oil pipe 20 can be indirectly driven to extend into the shaft by the lifting mechanism to adjust the extending length of the heat preservation oil pipe 20, and therefore the temperature of the shaft mouth is adjusted, on the basis, the length of the heat preservation oil pipe 20 is compensated by the arrangement of the penetrating oil pipe 30, and the whole oil pipe assembly can extend deep into the gas well to collect natural gas. Through the mutual matching of the components, the oil pipe component for the gas well can solve the problem of hydrate generation after throttling, and can replace two measures of ground heating and hydrate inhibitor adding of a water jacket furnace, so that the problems of the two measures are directly avoided.
It should be noted that, the lifting mechanism can be any lifting mechanism used for the oil pipe in the prior art, and the connection mode is generally a holding type, so that the oil pipe is convenient to be put on or taken off.
Preferably, in order to facilitate the make-up and break-out, the fixed oil pipe 10, the insulating oil pipe 20 and the penetration oil pipe 30 are coaxially and detachably connected by screw threads.
To further explain the specific structure of the insulating sleeve 21, the insulating sleeve 21 includes a first half hoop 211, a second half hoop 212, and a plurality of fixing members 213, where the first half hoop 211 and the second half hoop 212 can be clasped to form the insulating sleeve 21, and the fixing members 213 can maintain the clasped state of the first half hoop 211 and the second half hoop 212.
Through the arrangement, the heat preservation sleeve 21 is assembled in a cohesion mode, on one hand, butt joint of two ends of the heat preservation oil pipe 20 is not affected, and on the other hand, other heat preservation materials are conveniently arranged between the outer wall of the heat preservation oil pipe 20 and the inner wall of the heat preservation sleeve 21.
To further explain the specific shape and the fixing manner of the fixing member 213, the fixing member 213 is in a ring shape, and the fixing member 213 is sleeved outside the first half hoop 211 and the second half hoop 212.
Through the arrangement, the first half hoop 211 and the second half hoop after cohesion are limited and fixed in a sleeving and tightening mode, and the installation is convenient.
Preferably, in order to limit the mounting position of the fixing member 213 and prevent it from unnecessarily sliding along the axial direction of the insulating oil pipe 20, the insulating sleeve 21 includes a pair of fixing members 213, the outer diameters of the two ends of the first anchor ear 211 and the second anchor ear 212 in the length direction are smaller than the outer diameter of the middle portion, so as to form supporting edges 214 at the two ends, respectively, the inner diameter of the fixing member 213 is matched with and sleeved with the outer diameters of the two ends of the first anchor ear 211 and the second anchor ear 212 in the length direction, and the fixing member 213 is attached to the supporting edges 214.
Through the arrangement, the mounting position of the fixing piece 213 is limited at two axial ends of the heat preservation sleeve 21, the first hoop 211 and the second hoop 212 after cohesion are hooped from the two ends, the installation is convenient, the sleeved depth of the fixing piece 213 is limited through the support edge 214, and the fixing piece 213 is prevented from sliding to the middle part of the heat preservation oil pipe 20 along the axial direction of the heat preservation oil pipe 20.
In order to further improve the heat insulation performance of the heat insulation oil pipe 20 and the heat insulation sleeve 21 and to further limit the fixing piece 213, the outer walls of the two ends of the first anchor ear 211 and the second anchor ear 212 in the length direction are provided with external threads, the corresponding ends of the fixed oil pipe 10 and the penetrating oil pipe 30 are provided with internal threads, and the fixing piece 213 is clamped between the supporting edge 214 and the corresponding end of the fixed oil pipe 10 or the penetrating oil pipe 30.
Through the arrangement, when the heat preservation oil pipe 20 is connected with the fixed oil pipe 10 and the penetrating oil pipe 30, the two ends of the length direction of the heat preservation sleeve 21 are screwed into the fixed oil pipe 10 and the penetrating oil pipe 30, the contact area of the sealing surface of the connecting end is improved, the heat preservation performance of the heat preservation oil pipe 20 is further improved, the end faces of the fixed oil pipe 10 and the penetrating oil pipe 30 can be tightly pressed against the fixing piece 213, the fixing piece 213 is thoroughly limited, and the structure is more stable.
Preferably, in order to further improve the heat insulation performance, a heat insulation layer 22 is sandwiched between the heat insulation sleeve 21 and the heat insulation oil pipe 20, the heat insulation layer 22 is uniformly applied on the outer wall of the heat insulation oil pipe 20 and compacted by the heat insulation sleeve 21, and the heat insulation layer 22 is made of any one or more of aerogel felt, microporous calcium silicate, titanium ceramic heat insulation board, aluminum silicate fiber blanket, plate aerogel and aerogel paint.
Referring to fig. 4 on the basis of fig. 1 to 3, the embodiment further provides a method for preventing and treating gas well hydrate, which comprises the following steps:
S0, predicting the productivity of the gas well;
s1, obtaining a preset length of the thermal insulation oil pipe;
s2, after the heat preservation oil pipe 20 of any oil pipe assembly for the gas well is lowered into the well for the preset length, ground throttling is implemented.
Specifically, step S0 includes the following specific steps:
S01, establishing a simulated three-dimensional acid etching crack extension model;
In particular, gas well reservoir reformation is an effective means of increasing gas well production, and reservoir reformation is currently being carried out prior to gas well production. The productivity after the gas well transformation is an important parameter influencing the running depth of the heat preservation oil pipe, and influences the heat preservation effect and the economy. Based on the existing two-dimensional acid fracturing model, only the flow of fluid in the fracture along the length direction of the fracture and the diffusion mass transfer along the wall surface of the fracture are considered, and the flow of acid liquor in the fracture height direction and the change of the acid liquor concentration along with time are ignored. Simulation results tend to be inaccurate when reservoir longitudinal heterogeneity is evident. Aiming at the problem of the constant change of the etching degree of the acid etching crack, a quasi-three-dimensional acid etching crack extension model considering acid etching-acid liquor fluid loss is established by adopting the Newton iteration method principle, and the prediction precision of the form of the acid etching crack is improved;
Four basic equations forming the simulated three-dimensional fracture extension model are obtained, and are respectively:
(1) Continuity equation:
(2) Equation of fluid pressure drop:
(3) Crack width equation:
w(x,t)=f2(p(x,t),H(x,t))
(4) Crack height control equation:
The four equations described above constitute a set of nonlinear equations for q (x, t), p (x, t), w (x, t), H (x, t). In order to be able to solve accurately, it is also necessary to supplement the corresponding initial conditions and boundary conditions:
Firstly, assuming that the liquid injection time is t and the crack length is L f, dividing the crack into a plurality of units along the length direction of the crack, solving a crack height control equation by using a standard fourth-order Dragon-Gerdostat method, solving the height h (x, t) and the displacement q (x, t) of each unit section by combining initial conditions and boundary conditions, and further solving the crack net pressure p (x, t) and the crack width w (x, t). The next iteration is performed using the calculated flow to the slit as a judgment condition, and finally, L f (t) is obtained by conservation of volume. The hypothetical fracture length L f is compared with the calculated L f (t) until the given accuracy requirement is met. The calculation shows that the method has good convergence and high calculation efficiency. The calculation flow block diagram is shown in fig. 5;
according to the deduction, adopting Matlab software to compile a simulated three-dimensional crack propagation model numerical solution program, and calculating the condition that the stress of a crack bottom layer and a crack cover layer is symmetrical;
S02, establishing a gas reservoir productivity prediction model based on crack morphology prediction;
Specifically, based on the tri-linear principle, a low permeability gas reservoir productivity prediction model considering crack morphology, stress sensitivity, slip effect and crack high-speed non-Darcy flow influence is established. Considering seepage of gas from a reservoir to a slot to be divided into two parts, namely a radial flow part in a gas reservoir matrix, wherein the radial flow part comprises two flow processes of radial flow taking a crack end point as a center and linear flow at two sides of the crack at the end of the crack, and the seepage part from the end of the crack to the bottom of the well in the crack is considered, and a seepage model diagram of the crack is shown in figure 6;
the flow equation between the fracture lattice and the matrix, fracture lattice is:
The model is solved from the tail end of the crack to the crack opening by adopting an iteration method, and the outflow quantity Q1 of the grid blocks of the opening is the yield of the crack, namely the yield after the fracturing transformation.
Further optionally, the obtaining the preset length of the thermal insulation oil pipe includes the following steps:
s11, establishing a shaft temperature-pressure coupling model;
S12, obtaining the hydrate generation temperature after ground throttling and the wellhead temperature without generating hydrate according to the shaft temperature-pressure coupling model;
s13, fitting any parameter of the oil pipe assembly for the gas well with a shaft temperature-pressure coupling model to obtain a thermal insulation oil pipe run-in length-wellhead temperature model;
s14, bringing the wellhead temperature which does not generate hydrate into a thermal insulation oil pipe run-in length-wellhead temperature model to obtain the preset length.
Still further optionally, the establishing a wellbore temperature-pressure coupling model includes the steps of:
s111, describing the overall heat transfer performance of the shaft by using the total heat transfer coefficient, quantifying and integrating each link in the fluid lifting process, and establishing a calculation formula of the total heat transfer coefficient of the shaft by taking the outer diameter of the heat preservation layer as a reference:
The heat-insulating heat-conducting sleeve comprises a heat-conducting sleeve body, wherein U is the total heat-conducting coefficient of a shaft, R 1 is the heat-conducting heat resistance of a production fluid and the inner wall of the oil pipe, the unit is (m 2) DEG C/W, R 2 is the heat-conducting heat resistance of the oil pipe, the unit is (m 2) DEG C/W, R 3 is the heat-conducting heat resistance of an insulating layer, the unit is (m 2) DEG C/W, R 4 is the radiation heat-conducting heat resistance of an annular medium, the unit is (m 2) DEG C/W, R 5 is the heat-conducting heat resistance of the annular medium, the unit is (m 2) DEG C/W, R 6 is the heat-conducting heat resistance of a sleeve pipe, the unit is (m 2) DEG C/W, and R 7 is the heat-conducting heat resistance of a cement layer;
s112, according to a calculation formula of the total heat transfer coefficient of the shaft, introducing the thermal physical property space distribution of the stratum, and establishing a shaft temperature-pressure coupling model, wherein the shaft temperature-pressure coupling model meets the following calculation formula:
The method comprises the steps of enabling theta to be included angle of a shaft and a horizontal plane, enabling dz to be a trace element body which is long along the shaft, enabling cp to be constant pressure specific heat capacity, enabling the cp to be the unit of J/(kg DEG C), enabling alpha v to be the volume expansion coefficient, enabling K -1;rins to be the outer diameter of an insulating layer, enabling G to be the unit of mass flow of produced liquid, enabling Te to be the original stratum temperature, enabling Ke to be the stratum heat conductivity coefficient of the place where the trace element section is located, enabling f (t D) to be the dimensionless temperature, enabling Tm to be the temperature of produced liquid in an oil pipe, enabling Ti to be the inner diameter of the oil pipe, enabling Km to be the heat conductivity coefficient of the produced liquid in the oil pipe, enabling v m to be the average flow rate of the produced liquid in the oil pipe, enabling lambda to be the darcy friction coefficient, and enabling ρm to be the average density of the produced liquid to be the unit of kg/m 3.
The step S13 specifically includes the following steps:
S131, different yields are given, well head temperature and pressure are predicted by using a well shaft temperature-pressure coupling model, a well shaft and a ground flow are used as a unified production system, and according to the predicted well head temperature and pressure, the hydrate generation temperature after ground throttling and the well head temperature without hydrate generation are predicted by using a graphic method or an empirical formula method in combination with pressure transmission, and the well head temperature is specifically shown in figure 7;
it should be noted that step S14 specifically includes the following steps:
S141, setting heat preservation oil pipes with different lengths and common oil pipe combinations, giving yield parameters, and calculating wellhead temperature by using a shaft temperature-pressure coupling model. When the wellhead temperature is higher than the temperature at which hydrate is not generated, the condition that the ground is not hydrated is satisfied, namely the minimum run-in length of the thermal insulation oil pipe is determined, and the method is concretely as shown in the following table:
hydrate formation temperatures corresponding to different wellhead pressures
The thermal insulation oil pipe run-in length-wellhead temperature model is shown in fig. 8.
The foregoing description of the embodiments has been provided for the purpose of illustrating the general principles of the invention, and is not meant to limit the scope of the invention, but to limit the invention to the particular embodiments, and any modifications, equivalents, improvements, etc. that fall within the spirit and principles of the invention are intended to be included within the scope of the invention.
Claims (10)
1. An oil line assembly for a gas well, comprising:
The lifting mechanism is connected with a fixed oil pipe (10), the fixed oil pipe (10) is vertically arranged, the lifting mechanism can enable the fixed oil pipe (10) to lift along the axial direction, and the fixed oil pipe (10) is provided with a safety valve (11);
The heat preservation oil pipe (20), the heat preservation oil pipe (20) is connected with the fixed oil pipe (10) in a coaxial and detachable way, and the heat preservation oil pipe (20) is coated with a heat preservation sleeve (21);
And the penetrating oil pipe (30) is coaxially and detachably connected with one end, far away from the fixed oil pipe (10), of the heat preservation oil pipe (20).
2. Tubing assembly for gas wells according to claim 1, characterized in that the fixed tubing (10), the insulated tubing (20) and the run-in tubing (30) are detachably connected coaxially by threads.
3. The oil tube assembly for a gas well according to claim 1, wherein the heat retaining sleeve (21) comprises a first half hoop (211), a second half hoop (212) and a plurality of fixing pieces (213), wherein the first half hoop (211) and the second half hoop (212) can be clasped to form the heat retaining sleeve (21), and the fixing pieces (213) can maintain the clasped state of the first half hoop (211) and the second half hoop (212).
4. A tubing assembly for a gas well according to claim 3, wherein the securing member (213) is annular, the securing member (213) being sleeved outside the clasped first half collar (211) and second half collar (212).
5. A tubing assembly for a gas well according to claim 4, wherein the insulating sleeve (21) comprises a pair of said fixtures (213);
The outer diameters of the two ends of the first anchor ear (211) and the second anchor ear (212) in the length direction are smaller than the outer diameter of the middle part, so that supporting edges (214) are formed at the two ends respectively;
The inner diameter of the fixing piece (213) is matched with and sleeved with the outer diameters of the two ends of the first hoop (211) and the second hoop (212) in the length direction, and the fixing piece (213) is attached to the supporting edge (214).
6. The oil pipe assembly for a gas well according to claim 5, wherein the outer walls of the two ends of the first anchor ear (211) and the second anchor ear (212) in the length direction are provided with external threads, the corresponding ends of the fixed oil pipe (10) and the penetrating oil pipe (30) are provided with internal threads, and the fixing piece (213) is clamped between the supporting edge (214) and the corresponding ends of the fixed oil pipe (10) or the penetrating oil pipe (30).
7. The oil pipe assembly for a gas well according to any one of claims 1-6, wherein an insulation layer (22) is sandwiched between the insulation sleeve (21) and the insulation oil pipe (20), the insulation layer (22) being uniformly laid on the outer wall of the insulation oil pipe (20) and compacted by the insulation sleeve (21);
The heat insulation layer (22) is made of any one or more of aerogel felt, microporous calcium silicate, titanium ceramic heat insulation board, aluminum silicate fiber blanket, platy aerogel and aerogel coating.
8. A method for controlling gas well hydrates, which is characterized by comprising the following steps:
Obtaining the preset length of the thermal insulation oil pipe;
after running a thermal tubing (20) of a tubing assembly for a gas well according to any of claims 1-7 into the well for said predetermined length, surface throttling is performed.
9. The method for preventing and controlling gas well hydrates according to claim 8, wherein the step of obtaining a preset length of the run of the insulated oil pipe comprises the steps of:
establishing a shaft temperature-pressure coupling model;
obtaining the hydrate generation temperature after ground throttling and the wellhead temperature without generating hydrate according to the shaft temperature-pressure coupling model;
Fitting parameters of the tubing assembly for a gas well of any one of claims 1-7 to a wellbore temperature-pressure coupling model to obtain a thermal tubing run-in length-wellhead temperature model;
and carrying the wellhead temperature which does not generate hydrate into a thermal insulation oil pipe run-in length-wellhead temperature model to obtain the preset length.
10. The method of gas well hydrate control according to claim 9, wherein the establishing a wellbore temperature-pressure coupling model comprises the steps of:
Establishing a calculation formula of the total heat transfer coefficient of the shaft:
Wherein:
U is the total heat transfer coefficient of the shaft;
R 1 is the convective heat transfer resistance of the production fluid and the inner wall of the oil pipe, and the unit is (m 2℃)/W;
R 2 is the heat conduction resistance of the oil pipe, and the unit is (m 2℃)/W;
R 3 is the heat conduction resistance of the heat preservation layer, and the unit is (m 2℃)/W;
r 4 is the radiation heat transfer resistance of the annular medium, and the unit is (m 2℃)/W;
R 5 is the convective heat transfer resistance of the annular medium, and the unit is (m 2℃)/W;
R 6 is the heat conduction resistance of the sleeve, and the unit is (m 2℃)/W;
r 7 is the heat conduction resistance of the cement layer, and the unit is (m 2℃)/W;
according to a calculation formula of the total heat transfer coefficient of the shaft, introducing the thermal physical property space distribution of the stratum, and establishing a shaft temperature-pressure coupling model, wherein the shaft temperature-pressure coupling model meets the following calculation formula:
Wherein:
θ is the angle between the shaft and the horizontal plane;
dz is a minor element taken along the wellbore;
cp is the specific heat capacity of constant pressure, and the unit is J/(kg DEG C);
Alpha v is the volume expansion coefficient, in K -1;
r ins is the outer diameter of the heat-insulating layer, and the unit is m;
G is the mass flow rate of the production liquid, and the unit is kg/s;
Te is the original formation temperature in degrees Celsius;
Ke is the stratum heat conductivity coefficient of the position where the infinitesimal section is located, the unit is W/(m.DEG C), and f (tD) is the dimensionless temperature;
Tm is the temperature of the produced liquid in the oil pipe, and the unit is the temperature;
ti is the inner diameter of the oil pipe, and the unit is m;
km is the heat conductivity coefficient of the produced liquid in the oil pipe, and the unit is W/(m DEG C);
v m is the average flow velocity of the produced liquid in the oil pipe, and the unit is m/s;
lambda is the darcy friction coefficient;
ρm is the average density of the produced liquid, and the unit is kg/m 3.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103114828A (en) * | 2012-02-21 | 2013-05-22 | 中国石油化工股份有限公司 | Setting method of underground throttle technological parameter |
| CN205136853U (en) * | 2015-11-18 | 2016-04-06 | 天津新翔油气技术有限公司 | Nanometer compound incubation oil pipe |
| CN106907114A (en) * | 2017-05-08 | 2017-06-30 | 刘兴仁 | Nano heat-insulating thermal insulation tubing is wrapped up in outside a kind of |
| CN108425653A (en) * | 2018-03-26 | 2018-08-21 | 杨颖辉 | Gas well Operating Pressure wellhead assembly |
| CN208152953U (en) * | 2018-04-11 | 2018-11-27 | 中国石油化工股份有限公司 | A kind of two-layer compound thermal insulation tubing |
| CN111119795A (en) * | 2019-12-09 | 2020-05-08 | 森诺科技有限公司 | Novel gas production process |
| CN111441736A (en) * | 2020-03-23 | 2020-07-24 | 深圳市百勤石油技术有限公司 | Underwater natural gas hydrate wellhead device with heat preservation function |
| US10815778B1 (en) * | 2019-12-02 | 2020-10-27 | China University Of Petroleum (East China) | Method for obtaining formation parameters of gas hydrate reservoir through well testing interpretation |
| CN112065335A (en) * | 2020-08-11 | 2020-12-11 | 中国石油天然气股份有限公司 | Heat-insulation gas production pipe column and gas production method and application method thereof |
| CN113108137A (en) * | 2021-04-14 | 2021-07-13 | 浙江千禧龙纤特种纤维股份有限公司 | Tubing with ultrahigh molecular polyethylene fiber lining pipe and production method thereof |
-
2023
- 2023-08-09 CN CN202311001412.2A patent/CN119466604B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103114828A (en) * | 2012-02-21 | 2013-05-22 | 中国石油化工股份有限公司 | Setting method of underground throttle technological parameter |
| CN205136853U (en) * | 2015-11-18 | 2016-04-06 | 天津新翔油气技术有限公司 | Nanometer compound incubation oil pipe |
| CN106907114A (en) * | 2017-05-08 | 2017-06-30 | 刘兴仁 | Nano heat-insulating thermal insulation tubing is wrapped up in outside a kind of |
| CN108425653A (en) * | 2018-03-26 | 2018-08-21 | 杨颖辉 | Gas well Operating Pressure wellhead assembly |
| CN208152953U (en) * | 2018-04-11 | 2018-11-27 | 中国石油化工股份有限公司 | A kind of two-layer compound thermal insulation tubing |
| US10815778B1 (en) * | 2019-12-02 | 2020-10-27 | China University Of Petroleum (East China) | Method for obtaining formation parameters of gas hydrate reservoir through well testing interpretation |
| CN111119795A (en) * | 2019-12-09 | 2020-05-08 | 森诺科技有限公司 | Novel gas production process |
| CN111441736A (en) * | 2020-03-23 | 2020-07-24 | 深圳市百勤石油技术有限公司 | Underwater natural gas hydrate wellhead device with heat preservation function |
| CN112065335A (en) * | 2020-08-11 | 2020-12-11 | 中国石油天然气股份有限公司 | Heat-insulation gas production pipe column and gas production method and application method thereof |
| CN113108137A (en) * | 2021-04-14 | 2021-07-13 | 浙江千禧龙纤特种纤维股份有限公司 | Tubing with ultrahigh molecular polyethylene fiber lining pipe and production method thereof |
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| CN119466604B (en) | 2026-01-02 |
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