CN-114687688-B - High-temperature shale gas long horizontal well drilling temperature control system and method

Abstract

The invention discloses a high-temperature shale gas long horizontal well drilling temperature control system and a high-temperature shale gas long horizontal well drilling temperature control method, which belong to the technical field of drilling engineering. The drilling assembly includes a rotary steerable tool, a screw motor, and a drill rod. Meanwhile, the invention also discloses a high-temperature shale gas long horizontal well drilling temperature control method. According to the invention, the bottom hole circulating temperature of the drilling fluid is simulated by adopting methods of theoretical analysis, field test data fitting and the like, and the conditions of different parameters on the bottom hole circulating temperature of the drilling fluid are simulated and observed by adjusting the density of the drilling fluid, the displacement of a slurry pump, the drilling tool assembly, the revolution of the drilling tool assembly and the like, so that a reference basis is provided for optimizing the construction parameters of a deep high-temperature drilling field.

Inventors

• FENG MING
• YANG HENGLIN
• WANG YUAN
• FU LI
• GUO KAIJIE
• CHEN GANG

Assignees

• 中国石油天然气集团有限公司
• 中国石油集团工程技术研究院有限公司

Dates

Publication Date

20260512

Application Date

20220107

Claims (3)

1. 1. A high-temperature shale gas long horizontal well drilling temperature control method is characterized in that a high-temperature shale gas long horizontal well drilling temperature control system is adopted, the high-temperature shale gas long horizontal well drilling temperature control system comprises a drilling tool assembly (114), a ground cooling device (118), a slurry pump (110), a top drive (113) and a solid control device (103), the drilling tool assembly (114) is arranged in a well bore (116) to form an annulus with the well bore (116), drilling fluid returned from a drilling horn (101) enters the solid control device (103) along an overhead tank (102), part of solid phase content is removed, the drilling fluid enters a conical tank (104) through a runner of a conical tank (104) at the lower part of the solid control device (103), the conical tank (104) is connected with a vertical heat exchanger (107) through a valve (105), a centrifugal pump (106) and a pipeline (117), the obtained low-temperature fluid returns to an upper cement slurry tank (109) after the first-stage cooling is carried out by the valve (105), the slurry fluid enters the pipeline (117), the drilling fluid enters a pump (110) and enters a vertical heat exchanger (113) through a top drive hose (112), and is circulated again through the drilling fluid (112) after the drilling fluid enters the bottom pump (116), repeating the above process, wherein the ground cooling device (118) consists of a valve (105), a centrifugal pump (106), a vertical heat exchanger (107), a cooling tower (108) and a pipeline (117); the high-temperature shale gas long horizontal well drilling temperature control method comprises the following steps: Step 1, acquiring vertical depth, inclined depth, borehole track, mechanical rotation speed, displacement, drilling fluid density, drilling fluid rheological parameters, drilling fluid thermophysical parameters, geothermal gradient, stratum thermophysical parameters and well structure parameters of a well; Step 2, predicting that when the highest circulating temperature of the well drilling fluid at the bottom of the well exceeds 135 ℃, the well should be provided with a ground cooling device; Step 3, adopting a sectional circulation mode in the drilling process, circulating the borehole for more than 15 minutes when the static temperature reaches a well section at 125 ℃, circulating 5 upright posts once in each subsequent drilling operation, wherein the circulation time is more than 15 minutes each time, and continuously pumping the subsequent well section to drill when the temperature is still higher than the well section at 125 ℃ after the drilling operation; Step 4, before the drilling is carried out to a horizontal section, a well team should ensure that a slurry pump (110) and a ground pipeline (117) are in a ready-to-use state, and a ground cooling device (118) service side should ensure that the ground cooling device (118) is synchronously and continuously used in a high-temperature drilling circulation process; Step 5, when the well bottom circulating temperature exceeds 135 ℃ and reaches the early warning temperature of a rotary guiding tool of a drilling tool assembly (114) during horizontal section drilling, the drilling tool is in a stand column range, the top drive rotating speed is controlled to adopt drilling displacement for circulating cooling, and the drilling can be resumed when the temperature is stably reduced to 135 ℃ or the requirement of the rotary guiding tool is met; Step 6, stopping the pump later and starting the pump earlier when the stand column is connected so as to reduce the time of stopping the pump as much as possible, starting the pump to the drilling displacement after the stand column is connected, and then rotating the top drive, wherein the drilling tool is strictly forbidden to rotate when the pump is stopped, and when a maintenance flushing pipe or other maintenance operations are met, a construction team shall establish underground continuous circulation to continuously reduce the underground temperature; step 7, respectively calculating the circulation temperature of the drilling fluid in the drilling tool assembly (114), the circulation temperature of the drilling fluid in the annulus and the temperature of the drilling fluid entering the well through the following formulas; the temperature control equation in the drilling assembly (114) is as follows: drilling fluid heat transfer model within drilling assembly (114): ; Drilling tool assembly (114) wall heat transfer model: ; annulus drilling fluid heat transfer model ; Stratum, well cementation cement ring and casing heat transfer model ; Wherein Q p is the heat generated by friction in the drilling tool assembly (114), W/m; is the density of drilling fluid in the drilling tool assembly (114), kg/m 3 , q is the volume flow of the drilling fluid, m 3 /s;C p is the specific heat capacity of the drilling fluid, T p is the temperature of drilling fluid in the drilling assembly (114), C, T w is the temperature of drilling fluid in the drilling assembly (114), C, T a is the temperature of drilling fluid in the annulus, C, T f is the temperature of stratum near the well wall, C, T is the temperature of stratum, cement sheath and casing, C, z is depth, m, r p is the inner radius of the drilling assembly (114), m, r a is the outer radius of the drilling assembly (114), m, r o is the radius of the borehole (116), m, r is the radial distance from the center of the borehole 116, m, h p is the convective heat transfer coefficient of the inner wall of the drilling assembly (114), H a is the heat convection coefficient in the annulus of the borehole (116), T is time, s; And 8, optimizing the drilling fluid density, the rotating speed of the drilling assembly (114) in drilling parameters and the discharge capacity of a slurry pump (110) after obtaining the drilling fluid circulation temperature in the drilling assembly (114) and the drilling fluid circulation temperature in the annulus of the borehole (116) according to the step 7 to obtain the subsequent drilling fluid bottom hole circulation temperature, and continuously taking part in the circulation cooling of the drilling fluid returning to the drilling horn mouth (101) in the next stage.
2. 2. The method for controlling the temperature of long horizontal well drilling of high-temperature shale gas according to claim 1, wherein the system parameters are a slurry pump (110), a displacement of 30L/s, a rotation speed of a drilling tool assembly (114) of 80rpm, a torque of the drilling tool assembly (114) of 10 kN.m, the drilling tool assembly (114) adopts 139.7mm+127mm combination, the density of drilling fluid is 2.1g/cm 3 , and the well entering temperature of the drilling fluid at the drilling tool assembly (114) is 30 ℃.
3. 3. The method of controlling the temperature of a long horizontal well drilling of a high temperature shale gas as claimed in claim 1, wherein in step 3, the slurry pump (110) is circulated using the drilling displacement.

Description

High-temperature shale gas long horizontal well drilling temperature control system and method Technical Field The invention relates to the technical field of drilling engineering, in particular to a high-temperature shale gas long horizontal well drilling temperature control system and method. Background At present, related technologies and devices for cooling the bottom of a well of a drilling fluid mostly adopt a ground cooling method, namely, cooling the drilling fluid in a shaft by reducing the well entering temperature of the drilling fluid. However, according to the calculation result of the related theoretical model and the acquired data on site, the method for reducing the well entering temperature of the drilling fluid by the ground cooling device can only partially reduce the well bottom circulating temperature of the drilling fluid, and the further method for controlling the well temperature needs to be realized by optimizing the drilling parameters. At present, researchers develop temperature control methods through a large number of theoretical analysis and field downhole temperature test data fitting methods, and develop sensitivity analysis on the influence of various drilling process parameters on the downhole circulating temperature of drilling fluid. In the prior art, a high-temperature shale gas long horizontal well drilling temperature control system and method are needed. Disclosure of Invention The invention aims to overcome the defects in the prior art, provides a high-temperature shale gas long horizontal well drilling temperature control system and a high-temperature shale gas long horizontal well drilling temperature control method, adopts a method of theoretical analysis, field test data fitting and the like to simulate the bottom hole circulating temperature of drilling fluid, simulates and observes the conditions of different parameters on the bottom hole circulating temperature of the drilling fluid by adjusting the density of the drilling fluid, the displacement of a slurry pump, the rotation number of a top drive, a drilling tool combination and the like, and provides a reference basis for optimizing construction parameters of a deep high-temperature drilling field. Embodiments of the present invention are implemented as follows: In one aspect, the embodiment of the invention provides a high-temperature shale gas long horizontal well drilling temperature control system, which comprises a drilling tool assembly 114, a ground temperature reducing device 118, a top drive 113, a slurry pump 110 and a solid control device 103. Drilling fluid returned from the drilling horn 101 enters the solid control equipment 103 along the overhead tank 102, part of solid phase content is removed, the drilling fluid enters the conical tank 104 through a runner of a conical tank 104 at the lower part of the solid control equipment 103, the conical tank is connected with the vertical heat exchanger 107 through a valve 105, a centrifugal pump 106 and a pipeline 117, the drilling fluid enters the vertical heat exchanger 107 through the valve 105, the centrifugal pump 106 and the pipeline 117, the obtained low-temperature drilling fluid returns to the cement paste tank 109 after primary cooling, the drilling fluid enters the slurry pump 110 through the pipeline 117, enters the hose 112 through the vertical pipe 111, enters the drilling tool assembly 114 through the top drive 113, and the drilling fluid is circulated to the bottom of a well and then circulated again through the drilling horn 101 by the borehole 116, so that the above processes are repeated. The ground cooling device comprises a valve 105, a centrifugal pump 106, a vertical heat exchanger 107, a cooling tower 108 and a pipeline 117. The relative positional relationship of each component refers to the relative petroleum standard. The cooling medium of the primary vertical heat exchanger 107 and the drilling fluid are in parallel flow heat exchange, and the vertical heat exchanger 107 is all externally arranged, so that the device has the characteristics of small occupied area, high efficiency and convenience in maintenance. The cooling tower 108 is adopted to cool the high-temperature cooling medium discharged by the primary vertical heat exchanger 107, so that the cooling medium can be recycled, and the problem that the drilling operation platform has no water source or is difficult to supply water source is solved. The cooled drilling fluid is injected into the drilling assembly 114 from the wellhead through the two slurry pumps 110, the riser 111, the hose 112 and the top drive 113 at the well entering temperature and flows downwards to the bottom of the well, and in the downward flowing process, on one hand, heat exchange is carried out with the drilling fluid in the annulus, and on the other hand, heat is generated by viscous dissipation of the fluid in the flowing process in the drill pipe. The drilling fluid flows up and out of