Low-temperature and low-density cement slurry mixing device and mixing process

Abstract

This invention relates to the field of oilfield cementing equipment, and more particularly to a low-temperature, low-density cement slurry preparation and mixing equipment and process, aiming to alleviate the technical problem of difficulty in controlling temperature and mixing uniformity during cement slurry preparation in related technologies. The low-temperature, low-density cement slurry preparation and mixing equipment includes a mixing tank comprising an inner cylinder and an outer cylinder, with an annular space formed between the inner and outer cylinders. An upper and lower opening is provided on the side wall of the mixing tank. A stirring mechanism is used to stir the mixture within the inner cylinder. A temperature control mechanism includes a temperature sensor, a first guide screw, and a first drive assembly. The temperature sensor is located inside the inner cylinder, the first guide screw is located within the annular space, and the first drive assembly is drively connected to the first guide screw and also communicatively connected to the temperature sensor. This low-temperature, low-density cement slurry preparation and mixing equipment can ensure the mixing uniformity during cement slurry preparation and control the temperature, ensuring that the quality of the prepared cement slurry meets requirements.

Description

Technical Field

[0001] This invention relates to the field of oilfield cementing equipment, and more particularly to a low-temperature, low-density cement slurry mixing and preparation equipment and mixing process. Background Technology

[0002] Low-temperature, low-density cement slurry is a building material widely used in the oil and gas industry. It is used to reinforce and protect oil and gas storage and transportation facilities to ensure their stability and safety.

[0003] During preparation, various raw materials need to be mixed and stirred to ensure that the quality and performance of the cement slurry reach the required level. However, the temperature and mixing uniformity during the preparation process are often difficult to control, resulting in adverse effects. For example, excessively high temperatures will cause the cement slurry to harden too quickly, affecting its strength and stability; conversely, excessively low temperatures will cause the cement slurry to harden too slowly, affecting its construction efficiency and quality. Incomplete mixing of raw materials will lead to unstable performance of the cement slurry, affecting its strength and durability. Summary of the Invention

[0004] The purpose of this invention is to provide a low-temperature, low-density cement slurry preparation and mixing equipment and mixing process to alleviate the technical problem of difficulty in controlling temperature and mixing uniformity during cement slurry preparation in related technologies.

[0005] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows:

[0006] In a first aspect, the present invention provides a low-temperature, low-density cement slurry mixing and adjusting device, comprising: a mixing tank, including an inner cylinder and an outer cylinder, wherein an annular space is formed between the inner cylinder and the outer cylinder, and an upper opening and a lower opening are provided on its side wall; a stirring mechanism for stirring the mixture in the inner cylinder; and a temperature control mechanism, including a temperature sensor, a first guide screw, and a first drive assembly, wherein the temperature sensor is disposed in the inner cylinder, the first guide screw is located in the annular space, and the first drive assembly is drively connected to the first guide screw and also communicatively connected to the temperature sensor.

[0007] Furthermore, the first drive component includes a rotating ring and a first driver;

[0008] The rotating ring is sleeved on the inner cylinder and rotates with the mixing box, and a first toothed ring is fixed on it;

[0009] One end of the first feed guide screw is fixed to the rotating ring;

[0010] The output of the first driver is connected to a first gear, which meshes with the first gear ring.

[0011] Furthermore, the low-temperature, low-density cement slurry mixing and adjusting equipment also includes a defoaming mechanism, which includes a feed cylinder and a negative pressure pump;

[0012] The feed tube is a cylindrical shape with openings at both ends. One end is located outside the mixing tank and is connected to the negative pressure pump. The other end extends axially into the inner cylinder and is fixed with a tapered tube. A flow hole communicating with the upper opening is provided on its side wall.

[0013] Furthermore, the defoaming mechanism also includes a second guide screw and a second drive assembly;

[0014] The second guide screw is located inside the guide cylinder and between the upper opening and the lower opening, and its extension direction is consistent with the axial direction of the guide cylinder;

[0015] The second drive assembly is connected to the second guide screw to drive the second guide screw to rotate about its own axis.

[0016] Furthermore, the second drive assembly includes a rotating shaft, a second gear, a second gear ring, a third gear, and a second driver.

[0017] One end of the rotating shaft is located outside the guide cylinder and the mixing box, and the other end extends along the axial direction of the guide cylinder into the guide cylinder;

[0018] The second gear is located outside the mixing box and rotates with the mixing box, and is also fixedly connected to the rotating shaft;

[0019] The inner and outer sidewalls of the second gear ring mesh with the second gear and the third gear, respectively;

[0020] The output of the second driver is connected to the third gear.

[0021] Furthermore, the defoaming mechanism also includes a stirring rod and a liquid level sensor located inside the feed cylinder;

[0022] The shredding rod is also located between the upper opening and the second guide screw blade, and the second drive assembly is also connected to the shredding rod in a transmission manner;

[0023] The liquid level sensor is communicatively connected to the negative pressure pump, and is located on the side of the upper opening away from the second feed screw blade in the axial direction of the feed cylinder.

[0024] Furthermore, the stirring mechanism includes a stirring shaft, an inner stirring blade, an outer stirring blade, and a third driver;

[0025] The stirring shaft passes through the inner cylinder along the axial direction and is rotatably connected to the mixing box;

[0026] The inner stirring plate is sickle-shaped, with one end fixedly connected to the side wall of the stirring shaft and the other end inclined towards the top of the mixing tank;

[0027] The inner stirring blades are provided in multiple groups, and the multiple groups of inner stirring blades are distributed at intervals along the axial direction of the stirring shaft. In each group, multiple inner stirring blades are distributed at intervals along the circumferential direction of the stirring shaft.

[0028] The external stirring plate is also sickle-shaped, with one end fixedly connected to the side wall of the stirring shaft and the other end inclined away from the top of the mixing tank;

[0029] The outer stirring blades are also provided in multiple sets, and the multiple sets of outer stirring blades are staggered with the inner stirring blades along the axial direction of the stirring shaft, and in each set, multiple outer stirring blades are also distributed at intervals along the circumferential direction of the stirring shaft.

[0030] The third driver is connected to the stirring shaft via a drive mechanism.

[0031] Furthermore, heat dissipation fins are provided on the outer wall of the outer cylinder.

[0032] Furthermore, the mixing chamber also includes a cover, which covers the inner cylinder and has multiple feed pipes communicating with the inner cylinder.

[0033] The bottom of the inner cylinder is provided with a discharge pipe, which is connected to the inner cylinder.

[0034] Secondly, the present invention also provides a low-temperature, low-density cement slurry preparation and mixing process, which is based on the low-temperature, low-density cement slurry preparation and mixing equipment described above, and includes the following steps;

[0035] S1: The required cement slurry mixture is introduced into the inner cylinder through each feed pipe;

[0036] S2: Start the third drive to rotate the stirring shaft;

[0037] S3: Start the first driver to drive the first guide screw to spiral upward, so that the cement slurry in the inner cylinder enters the annulus through the lower port and is transmitted upward by the first guide screw;

[0038] S4: Start the second driver to drive the shaft to rotate, causing the second guide screw to spiral downwards and guide the material. At the same time, start the negative pressure pump and monitor whether the cement slurry has submerged the liquid level sensor. If so, reduce the exhaust power of the negative pressure pump; otherwise, increase the exhaust power of the negative pressure pump.

[0039] S5: The temperature range ΔT of the preset temperature sensor is set. When the monitored temperature T is lower or higher than ΔT, feedback is sent to the first driver to reduce or increase the operating power of the first driver accordingly, until the monitored temperature T is at the middle value of ΔT, and then the operating power of the first driver is maintained at this time.

[0040] In summary, the technical effects achieved by the low-temperature, low-density cement slurry mixing and adjusting equipment provided by this invention are as follows:

[0041] In this mixing device, the inner cylinder is a mixing chamber for cement slurry and cement slurry preparation. A temperature sensor installed inside the inner cylinder can monitor the temperature of the cement slurry in real time. As the hydration reaction of the cement slurry raw materials proceeds, the heat in the mixing chamber will continuously increase. The first drive component drives the first guide screw to spiral upward, and the cement slurry in the inner cylinder will enter the annulus through the lower port and be transferred upward in real time by the first guide screw. Then, it will return to the inner cylinder through the upper port, realizing the circulation and exchange between the inner cylinder and the annulus.

[0042] As mentioned above, during the circulation process, the cement slurry is fully mixed, ensuring the uniformity of the mixing among the raw materials. Furthermore, the heat of the cement slurry in the annulus will diffuse outward from the outer cylinder wall, thus being cooled and keeping the temperature of the cement slurry during mixing within a certain range. In addition, if the temperature detected by the temperature sensor is higher than the preset range, the operating power of the first drive component will be greater, accelerating the heat dissipation of the cement slurry in the annulus. Conversely, the operating power of the first drive component will be reduced accordingly until the monitored temperature is within the preset optimal temperature range.

[0043] It can be seen that, compared with existing technologies, this low-temperature, low-density cement slurry mixing equipment can ensure the uniformity of mixing during the cement slurry preparation process and control the temperature, so that the quality of the cement slurry produced meets the requirements. Attached Figure Description

[0044] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0045] Figure 1 This is a schematic diagram of the structure of a low-temperature, low-density cement slurry mixing and adjusting device provided in an embodiment of the present invention;

[0046] Figure 2 A partial cross-sectional view of the low-temperature, low-density cement slurry mixing equipment provided in an embodiment of the present invention;

[0047] Figure 3 This is a schematic diagram of a partial structure of a low-temperature, low-density cement slurry mixing and adjusting device provided in an embodiment of the present invention.

[0048] Icons: 100 - Mixing box; 110 - Inner cylinder; 120 - Outer cylinder; 130 - Annular space; 140 - Shell cover; 111 - Top opening;

[0049] 200 - Stirring mechanism; 210 - Stirring shaft; 220 - Inner stirring blade; 230 - Outer stirring blade; 240 - Third drive;

[0050] 300 - Temperature control mechanism; 310 - Temperature sensor; 320 - First guide screw blade; 330 - Rotating ring; 340 - First driver; 350 - First gear ring; 360 - First gear;

[0051] 400 - Defoaming mechanism; 410 - Feed guide cylinder; 420 - Negative pressure pump; 430 - Conical tube; 440 - Second feed guide vane; 450 - Rotating shaft; 460 - Second gear; 470 - Second gear ring; 480 - Third gear; 490 - Second actuator; 4100 - Agitation rod; 4110 - Liquid level sensor; 4120 - Fine screw;

[0052] 500 - Heat dissipation fins; 600 - Feed pipe; 700 - Discharge pipe. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0054] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0055] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0056] During the preparation of low-temperature, low-density cement slurry, the temperature and mixing uniformity are often difficult to control, which can have adverse effects.

[0057] In view of this, the present invention provides a low-temperature, low-density cement slurry mixing and adjusting device, including a mixing tank 100, comprising an inner cylinder 110 and an outer cylinder 120, with an annular space 130 formed between the inner cylinder 110 and the outer cylinder 120, and an upper opening 111 and a lower opening provided on its side wall; a stirring mechanism 200 for stirring the mixture in the inner cylinder 110; and a temperature control mechanism 300, comprising a temperature sensor 310, a first guide screw 320, and a first drive assembly, wherein the temperature sensor 310 is disposed in the inner cylinder 110, the first guide screw 320 is disposed in the annular space 130, and the first drive assembly is drively connected to the first guide screw 320 and also communicatively connected to the temperature sensor 310.

[0058] In this mixing device, the inner cylinder 110 is a mixing chamber for cement slurry and cement slurry preparation. The temperature sensor 310 installed in the inner cylinder 110 can monitor the temperature of the cement slurry in real time. As the hydration reaction of the cement slurry raw materials proceeds, the heat in the mixing chamber will continuously increase. The first drive component drives the first guide screw 320 to spirally guide the material upward. The cement slurry in the inner cylinder 110 will enter the annulus 130 through the lower port and be transferred upward in real time by the first guide screw 320. Then, it will return to the inner cylinder 110 through the upper port 111, realizing the circulation and exchange between the inner cylinder 110 and the annulus 130.

[0059] As mentioned above, during the circulation process, the cement slurry is fully mixed, ensuring the uniformity of the mixing among the raw materials. Furthermore, the heat of the cement slurry in the annulus 130 will diffuse outward from the outer cylinder 120 wall and be cooled, keeping the temperature of the cement slurry during mixing within a certain range. In addition, if the temperature monitored by the temperature sensor 310 is higher than the preset range, the operating power of the first drive component will be greater, accelerating the heat dissipation of the cement slurry in the annulus 130. Conversely, the operating power of the first drive component will be reduced accordingly until the monitored temperature is within the preset optimal temperature range.

[0060] It can be seen that, compared with existing technologies, this low-temperature, low-density cement slurry mixing equipment can ensure the uniformity of mixing during the cement slurry preparation process and control the temperature, so that the quality of the cement slurry produced meets the requirements.

[0061] The following combination Figures 1 to 3 The structure and shape of the low-temperature, low-density cement slurry mixing equipment provided in this embodiment are described in detail below:

[0062] In this embodiment, reference Figures 1 to 3The mixing chamber 100 also includes a cover 140, which is located on the top of the inner cylinder 110. A third drive 240, which is a motor, is fixed to the outside of the cover 140. A stirring shaft 210 is rotatably mounted at the center of the cover 140. The upper end of the stirring shaft 210 is connected and fixed to the output of the motor. Alternating inner stirring blades 220 and outer stirring blades 230 are provided on the side wall, and the bottom end extends to near the bottom wall of the inner cylinder 110. Multiple feed pipes 600 are connected to the shell surface of the cover 140, and a discharge pipe 700 is connected to the middle of the bottom end of the inner cylinder 110. The mixing chamber 100 is also provided with a defoaming mechanism 400 for defoaming the cement slurry.

[0063] As described above, the inner cylinder 110 and the outer cylinder 120 are concentrically arranged, with the bottom end of the inner cylinder 110 and the bottom end of the outer cylinder 120 being sealed together. The side walls of the inner cylinder 110, the side walls of the outer cylinder 120, and the bottom wall of the outer cylinder 120 enclose an annular space 130. The upper opening 111 is close to the top of the annular space 130, and the lower opening is located at the bottom of the annular space 130. A guide cylinder 410 is also installed at the top of the inner cylinder 110, extending into the inner cylinder 110 and communicating with the upper opening 111.

[0064] Regarding the temperature control mechanism 300, specifically:

[0065] refer to Figure 2 and Figure 3 The first drive assembly includes a rotating ring 330 and a first driver 340. The rotating ring 330 is installed on the top of the annular cavity 130 and rotates in cooperation with the inner wall of the outer cylinder 120 and the outer wall of the inner cylinder 110. The first driver 340 is a motor. The upper end of the first guide screw 320 is fixedly connected to the rotating ring 330, and the lower end of the first guide screw 320 extends into the bottom of the annular cavity 130. The rotating ring 330 is fitted with a first toothed ring 350, which meshes with the first gear 360 installed at the output end of the first driver 340.

[0066] The inner cylinder 110 serves as a mixing chamber for cement slurry and cement slurry preparation. As the hydration reaction of the cement slurry raw materials proceeds, the heat in the mixing chamber will continuously increase, which can easily cause some cement slurry to deteriorate and damage the composition and structure of the cement slurry raw materials during the mixing process. For example, it may harden and form hard lumps or particles, which will have a certain impact on the subsequent use and solidification of the cement slurry and affect the quality of the finished cement slurry. In this embodiment, the first drive 340 drives the first gear 360 to rotate, which in turn drives the first gear ring 350 to rotate around its own axis. The first gear ring 350 and the rotating ring 330 rotate synchronously, driving the first guide screw 320 to spirally guide the material upward. The cement slurry in the inner cylinder 110 enters the annulus 130 through the lower opening and is transferred upward in real time by the first guide screw 320, so that the cement slurry circulates and exchanges between the inner cylinder 110 and the annulus 130. The heat of the cement slurry in the annulus 130 is diffused outward by the outer cylinder 120 wall to achieve cooling, so that the temperature of the cement slurry during mixing is within a certain range, such as controlled at an optimal temperature of 5℃-30℃, to obtain a high-quality cement slurry product. In addition, the design of the annulus 130 also has the effect of heat preservation of cement slurry.

[0067] More preferably, refer to Figure 1 The outer wall of the outer cylinder 120 is provided with heat dissipation fins 500, which can improve the heat dissipation efficiency of the annulus 130.

[0068] Preferably, the temperature sensor 310 is disposed on the side wall of the stirring shaft 210. In this way, the center temperature of the cement slurry can be monitored in real time and fed back to the first actuator 340. As the temperature increases, the operating power of the first actuator 340 increases until the monitored temperature is within the preset optimal temperature range.

[0069] Regarding the defoaming mechanism 400, specifically:

[0070] refer to Figure 2 and Figure 3The defoaming mechanism 400 includes a negative pressure pump 420, a rotating shaft 450, a second gear ring 470, and a second driver 490. The rotating shaft 450 extends into the guide cylinder 410 and is coaxially arranged with the guide cylinder 410. A second guide vane 440 is fixed on the side wall of the rotating shaft 450, and the second guide vane 440 is located below the upper opening 111. The top end of the rotating shaft 450 extends out of the guide cylinder 410 and is fixed with a second gear 460. The second gear ring 470 is rotatably mounted on the housing cover 140, and the second gear ring 470 includes an integral part of the housing cover 140. The inner gear and the outer gear are connected. The inner gear meshes with the second gear 460, and the outer gear meshes with the third gear 480 installed at the output end of the second driver 490. The second driver 490 is a motor. A liquid level sensor 4110 is installed outside the rotating shaft 450 located inside the guide cylinder 410 and above the upper opening 111. A negative pressure pump 420 is installed on the outer side of the top of the inner cylinder 110 and is connected to the liquid level sensor 4110. Its input end is connected to the upper end of the guide cylinder 410. A tapered tube 430 is installed at the lower opening of the guide cylinder 410.

[0071] In the above design, the flow channel of cement slurry in the guide cylinder 410 is reduced by the tapered tube 430. At the same time, the second driver 490 drives the rotating shaft 450 to rotate through the third gear 480, the second gear ring 470, and the second gear 460. The rotating shaft 450 drives the second guide screw 440 to guide the cement slurry downward, which accelerates and compresses the cement slurry. The negative pressure pump 420 exhausts the cavity of the guide cylinder 410 in real time, so that the guide cylinder 410 has a negative pressure effect. In addition, the liquid level sensor 4110 monitors whether the cement slurry submerges the liquid level sensor 4110. If it does, the exhaust power of the negative pressure pump 420 is reduced; if not, the exhaust power of the negative pressure pump 420 is increased, so that the exhaust power of the negative pressure pump 420 is in the optimal state in real time. This fully removes the air bubbles inside the cement slurry flowing through the guide cylinder 410 and increases the density of the cement slurry. Correspondingly, the preparation of cement slurry with different density requirements is more convenient and accurate.

[0072] Optionally, a crushing rod 4100 is installed outside the rotating shaft 450 located above the second feed screw 440, and the height of the crushing rod 4100 is lower than the height of the upper opening 111. This design further breaks up the solidified material in the cement slurry, fully mixes the raw materials, and thus improves the mixing uniformity of the cement slurry.

[0073] Furthermore, a thin screw 4120 extending through the tapered tube 430 is fixed to the lower end of the rotating shaft 450. This helps to improve the smoothness of cement slurry discharge from the guide cylinder 410.

[0074] In this embodiment, the lower end of the feed cylinder 410 is lower than the height of the cement slurry level in the inner cylinder 110.

[0075] In this embodiment, reference Figure 2Both the inner stirring plate 220 and the outer stirring plate 230 are sickle-shaped, with the outer end of the inner stirring plate 220 bent upwards and the outer end of the outer stirring plate 230 bent downwards. This design allows the inner stirring plate 220 and the outer stirring plate 230 to guide the flow radially inwards and outwards along the inner cylinder 110 in real time, driven by the stirring shaft 210. Furthermore, because the inner stirring plate 220 and the outer stirring plate 230 are staggered from top to bottom, they can fully mix the cement slurry, resulting in high-quality cement slurry.

[0076] This invention also provides a low-temperature, low-density cement slurry preparation and mixing process. This process is implemented based on the aforementioned low-temperature, low-density cement slurry preparation and mixing equipment, and includes the following steps:

[0077] S1: The required cement slurry mixture is introduced into the inner cylinder 110 through each feed pipe 600;

[0078] S2: Start the third driver 240 to drive the stirring shaft 210 to rotate, thereby driving the inner stirring plate 220 and the outer stirring plate 230 to rotate;

[0079] S3: Start the first driver 340, drive the first gear 360 to rotate, drive the first guide screw 320 to rotate through the first gear ring 350, spirally guide the material upward, and the cement slurry in the inner cylinder 110 enters the annulus 130 through the lower port, and is transmitted upward in real time by the first guide screw 320, so that the cement slurry circulates and exchanges between the inner cylinder 110 and the annulus 130.

[0080] S4: Start the second driver 490, drive the third gear 480 to drive the second gear ring 470 to rotate, and synchronously drive the second gear 460 to rotate, so that the second guide screw 440 rotates and spirals downward to guide the material. At the same time, start the negative pressure pump 420, and monitor whether the cement slurry submerges the liquid level sensor 4110 according to the liquid level sensor 4110. If so, reduce the exhaust power of the negative pressure pump 420; if not, increase the exhaust power of the negative pressure pump 420.

[0081] S5: The temperature range ΔT of the preset temperature sensor 310 is set. When the monitored temperature T is lower or higher than ΔT, feedback is sent to the first driver 340 to reduce or increase the operating power of the first driver 340 until the monitored temperature T is at the middle value of ΔT, and the operating power of the first driver 340 is maintained at this time.

[0082] This invention utilizes a temperature sensor 310 mounted on the stirring shaft 210 to monitor the center temperature of the cement slurry in real time. The inner cylinder 110 serves as a mixing chamber for the cement slurry and its additives. As the hydration reaction of the cement slurry raw materials proceeds, the heat in the mixing chamber continuously increases. The first drive 340 drives the first guide screw 320 to spirally guide the cement slurry upwards. The cement slurry in the inner cylinder 110 enters the annulus 130 through the lower opening and is continuously transferred upwards by the first guide screw 320, circulating and exchanging the cement slurry between the inner cylinder 110 and the annulus 130. The outer cylinder 120 wall diffuses the heat of the cement slurry in the annulus 130 outwards for cooling, regulating the temperature of the cement slurry during mixing and keeping it within a certain range. Furthermore, the design of the annulus 130 also provides insulation for the cement slurry.

[0083] In this invention, the flow channel of cement slurry in the guide cylinder 410 is reduced by the tapered tube 430. At the same time, the rotating shaft 450 drives the second guide screw 440 to guide the cement slurry downward, which accelerates the cement slurry and squeezes it. The negative pressure pump 420 exhausts the cavity of the guide cylinder 410 in real time, so that the guide cylinder 410 has a negative pressure effect, which fully discharges the air bubbles inside the cement slurry flowing through the guide cylinder 410, increases the density of the cement slurry, and makes the preparation of cement slurry with different density requirements more convenient and precise, thereby improving the quality of cement slurry.

[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-temperature, low-density cement slurry mixing and preparation device, characterized in that, include: A mixing chamber (100) includes an inner cylinder (110) and an outer cylinder (120), with an annular space (130) formed between the inner cylinder (110) and the outer cylinder (120), and an upper opening (111) and a lower opening provided on its side wall; a stirring mechanism (200) for stirring the mixture in the inner cylinder (110); a temperature control mechanism (300) including a temperature sensor (310), a first guide screw (320) and a first drive assembly, wherein the temperature sensor (310) is disposed in the inner cylinder (110), the first guide screw (320) is located in the annular space (130), and the first drive assembly is drivenly connected to the first guide screw (320) and also communicatively connected to the temperature sensor (310).

2. The low-temperature, low-density cement slurry mixing and adjusting equipment according to claim 1, characterized in that, The first drive assembly includes a rotating ring (330) and a first driver (340); The rotating ring (330) is sleeved on the inner cylinder (110) and rotates in cooperation with the mixing box (100), and a first toothed ring (350) is fixed on it; One end of the first guide screw (320) is fixed to the rotating ring (330); The output of the first driver (340) is connected to a first gear (360), which meshes with the first gear ring (350).

3. The low-temperature, low-density cement slurry mixing and adjusting equipment according to claim 1, characterized in that, The low-temperature, low-density cement slurry mixing equipment also includes a defoaming mechanism (400), which includes a feed cylinder (410) and a negative pressure pump (420). The feed guide cylinder (410) is a cylindrical shape with open ends. One end is located outside the mixing box (100) and is connected to the negative pressure pump (420). The other end extends along the axial direction of the inner cylinder (110) into the inner cylinder (110) and is fixed with a tapered tube (430). The side wall of the tapered tube is provided with a flow hole that communicates with the upper opening (111).

4. The low-temperature, low-density cement slurry mixing and adjusting equipment according to claim 3, characterized in that, The defoaming mechanism (400) also includes a second guide screw (440) and a second drive assembly; The second guide screw (440) is located inside the guide cylinder (410), and is also located between the upper opening (111) and the lower opening, and its extension direction is consistent with the axial direction of the guide cylinder (410); The second drive assembly is connected to the second guide vane (440) to drive the second guide vane (440) to rotate about its own axis.

5. The low-temperature, low-density cement slurry mixing and adjusting equipment according to claim 4, characterized in that, The second drive assembly includes a rotating shaft (450), a second gear (460), a second gear ring (470), a third gear (480), and a second driver (490); One end of the rotating shaft (450) is outside the guide cylinder (410) and the mixing box (100), and the other end extends along the axial direction of the guide cylinder (410) into the guide cylinder (410); The second gear (460) is located outside the mixing box (100) and rotates with the mixing box (100), and is also fixedly connected to the rotating shaft (450); The inner and outer sidewalls of the second gear ring (470) mesh with the second gear (460) and the third gear (480), respectively; The output of the second driver (490) is connected to the third gear (480).

6. The low-temperature, low-density cement slurry mixing and adjusting equipment according to claim 4, characterized in that, The defoaming mechanism (400) also includes a stirring rod (4100) and a liquid level sensor (4110) located inside the feed cylinder (410); The shredding rod (4100) is also located between the upper opening (111) and the second guide screw (440), and the second drive assembly is also connected to the shredding rod (4100) in a transmission connection; The liquid level sensor (4110) is communicatively connected to the negative pressure pump (420), and in the axial direction of the feed cylinder (410), the liquid level sensor (4110) is also located on the side of the upper port (111) away from the second feed screw (440).

7. The low-temperature, low-density cement slurry mixing and adjusting equipment according to claim 1, characterized in that, The stirring mechanism (200) includes a stirring shaft (210), an inner stirring blade (220), an outer stirring blade (230), and a third driver (240); The stirring shaft (210) passes through the inner cylinder (110) along the axial direction and is rotatably connected to the mixing box (100); The inner stirring plate (220) is sickle-shaped, with one end fixedly connected to the side wall of the stirring shaft (210), and the other end inclined towards the top of the mixing box (100); The inner stirring blades (220) are provided in multiple groups, and the multiple groups of inner stirring blades (220) are distributed at intervals along the axial direction of the stirring shaft (210). In each group, multiple inner stirring blades (220) are distributed at intervals along the circumferential direction of the stirring shaft (210). The external stirring plate (230) is also sickle-shaped, with one end fixedly connected to the side wall of the stirring shaft (210), and the other end inclined away from the top of the mixing box (100); The outer stirring blades (230) are also provided in multiple sets. The multiple sets of outer stirring blades (230) are staggered with the inner stirring blades (220) along the axial direction of the stirring shaft (210), and in each set, multiple outer stirring blades (230) are also distributed circumferentially along the stirring shaft (210). The third driver (240) is connected to the stirring shaft (210) in a driving connection.

8. The low-temperature, low-density cement slurry mixing and adjusting equipment according to claim 1, characterized in that, The outer wall of the outer cylinder (120) is provided with heat dissipation fins (500).

9. The low-temperature, low-density cement slurry mixing and adjusting equipment according to claim 1, characterized in that, The mixing chamber (100) also includes a cover (140), which covers the inner cylinder (110) and has a plurality of feed pipes (600) communicating with the inner cylinder (110). The bottom of the inner cylinder (110) is provided with a discharge pipe (700), which is connected to the inner cylinder (110).

10. A low-temperature, low-density cement slurry mixing process, characterized in that, Based on the low-temperature, low-density cement slurry mixing equipment as described in any one of claims 1 to 9, the process includes the following steps: S1: The required cement slurry mixture is introduced into the inner cylinder (110) through each feed pipe (600); S2: Start the third drive (240) to drive the stirring shaft (210) to rotate; S3: Start the first driver (340) to drive the first guide screw (320) to spiral upward, so that the cement slurry in the inner cylinder (110) enters the annulus (130) through the lower port and is transmitted upward by the first guide screw (320); S4: Start the second driver (490) to drive the rotating shaft (450) to rotate, so that the second guide screw (440) spirals downward to guide the material. At the same time, start the negative pressure pump (420) and monitor whether the cement slurry submerges the liquid level sensor (4110) according to the liquid level sensor (4110). If so, reduce the exhaust power of the negative pressure pump (420); if not, increase the exhaust power of the negative pressure pump (420). S5: The temperature range ΔT of the temperature sensor (310) is preset. When the monitored temperature T is lower or higher than ΔT, feedback is sent to the first driver (340) to reduce or increase the operating power of the first driver (340) accordingly until the monitored temperature T is at the middle value of ΔT. Then the operating power of the first driver (340) is maintained at this time.

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