A dehydration device for waste water-based drilling fluid

Abstract

This utility model relates to the field of drilling fluid treatment technology, and in particular to a dehydration device for waste water-based drilling fluid. It includes a pretreatment cylinder and a dehydration tank. The pretreatment cylinder contains a filter screen, and a stirring mechanism is located below the filter screen. A flocculant feeding pipe and a filter aid feeding pipe are installed on the side wall of the pretreatment cylinder. A discharge pipe is installed at the bottom of the pretreatment cylinder, and a solenoid valve is installed on the discharge pipe. A telescopic hose is connected to the discharge pipe. A filter cylinder is rotatably mounted at the bottom of the dehydration tank, and multiple filter holes are installed on the side wall of the filter cylinder. A centrifugal motor that drives the filter cylinder to rotate is installed at the bottom of the dehydration tank. A filter press mechanism is installed at the top of the dehydration tank, directly opposite the filter cylinder. A telescopic mechanism that drives the outlet end of the telescopic hose to move above the filter cylinder is installed on the dehydration tank. A drain pipe is located on one side of the bottom of the dehydration tank. This utility model effectively reduces the water content of solid mud cake, solving the problem of high water content in mud cake after traditional filtration and sedimentation treatment, and reducing subsequent transportation and disposal costs and the risk of secondary pollution.

Description

Technical Field

[0001] This utility model relates to the field of drilling fluid treatment technology, and more specifically to a dehydration device for waste water-based drilling fluid. Background Technology

[0002] In oil and gas drilling operations, water-based drilling fluids are commonly used working fluids, and a large amount of waste water-based drilling fluid is generated after the operation. This waste fluid contains a variety of solid components and chemical substances. If it is discharged directly without treatment, it can easily cause adverse effects on the soil, water bodies and other environmental environments. Therefore, it is necessary to achieve solid-liquid separation through dehydration treatment to meet environmental disposal requirements.

[0003] Currently used waste water-based drilling fluid dehydration technologies still have significant limitations in practical applications: On the one hand, the pretreatment of waste fluid is not perfect, with most relying on simple filtration or natural sedimentation, which cannot effectively remove fine impurities and viscous flocculent matter. These residual substances easily adhere to the surface of dehydration components or block the flow channels after entering the subsequent dehydration stage, leading to increased equipment operating resistance, frequent start-ups and shutdowns, seriously affecting the smoothness of the dehydration process, and even shortening the equipment's service life. On the other hand, even after filtration and sedimentation, existing dehydration equipment still produces solid mud cakes with high water content, which not only increases the cost of subsequent transportation and disposal of mud cakes but may also cause secondary pollution due to water seepage. Furthermore, the overall treatment efficiency is difficult to fully meet current actual needs. Utility Model Content

[0004] The purpose of this invention is to provide a dehydration device for waste water-based drilling fluid, which reduces the water content of solid mud cake and reduces subsequent transportation and disposal costs and the risk of secondary pollution.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows:

[0006] A dewatering device for waste water-based drilling fluid includes a pretreatment cylinder and a dewatering tank. The pretreatment cylinder contains a filter screen, and a stirring mechanism is located below the filter screen. A flocculant feeding pipe and a filter aid feeding pipe are installed on the side wall of the pretreatment cylinder, positioned between the filter screen and the stirring mechanism. A discharge pipe is installed at the bottom of the pretreatment cylinder, and a solenoid valve is installed on the discharge pipe. The discharge pipe is connected to a telescopic hose, which extends to the inside of the dewatering tank. A filter cylinder is rotatably mounted at the bottom of the dewatering tank, and multiple filter holes are installed on the side wall of the filter cylinder. A centrifugal motor is installed at the bottom of the dewatering tank to drive the filter cylinder to rotate. A filter press mechanism is installed at the top of the dewatering tank, directly opposite the filter cylinder. A telescopic mechanism is installed on the dewatering tank to move the outlet end of the telescopic hose above the filter cylinder. A drain pipe is located on one side of the bottom of the dewatering tank.

[0007] Furthermore, the stirring mechanism includes a rotating shaft rotatably disposed inside the pretreatment cylinder, a rotary motor for driving the rotating shaft to rotate is installed on the outside of the pretreatment cylinder, and multiple stirring blades are fixedly connected to the rotating shaft.

[0008] Furthermore, the filter press mechanism includes a hydraulic cylinder installed on the top of the dewatering tank. The driving end of the hydraulic cylinder is connected to a filter press plate, which is positioned directly opposite the filter cylinder. The outer diameter of the filter press plate is not greater than the inner diameter of the filter cylinder.

[0009] Furthermore, the telescopic mechanism includes an electric telescopic rod installed on the outer wall of the dehydration tank, and a fixing plate is fixedly connected to the drive end of the electric telescopic rod. The fixing plate is fixedly sleeved at the outlet end of the telescopic hose.

[0010] Furthermore, an electric heating plate is embedded in the bottom and side wall of the pretreatment cylinder.

[0011] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0012] This application uses a filter screen to intercept impurities such as rock cuttings and fibers in waste drilling fluid, preventing them from clogging subsequent filter cartridges or flow channels. The filter cartridges in the dewatering tank work in conjunction with a centrifugal motor to achieve preliminary solid-liquid separation through centrifugal force. The top pressure filter mechanism can perform secondary compression on the solid phase after centrifugation, forming a synergistic effect of "centrifugal pre-dewatering and pressure filtration deep dewatering", effectively reducing the water content of solid mud cake, solving the problem of "high water content of mud cake" after traditional filtration and sedimentation treatment, and reducing subsequent transportation and disposal costs and the risk of secondary pollution. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model;

[0014] Figure 2 This is a partial structural schematic diagram of the present invention.

[0015] 1. Pretreatment cylinder; 2. Dewatering tank; 3. Filter screen; 4. Flocculant feeding pipe; 5. Filter aid feeding pipe; 6. Discharge pipe; 7. Solenoid valve; 8. Telescopic hose; 9. Filter cylinder; 901. Filter holes; 10. Centrifugal motor; 11. Rotary shaft; 12. Rotary motor; 13. Stirring blades; 14. Hydraulic cylinder; 15. Filter press plate; 16. Electric telescopic rod; 17. Fixing plate; 18. Electric heating plate; 19. Drain pipe. Detailed Implementation

[0016] like Figure 1 and Figure 2As shown, a dewatering device for waste water-based drilling fluid includes a pretreatment cylinder 1 and a dewatering tank 2. A filter screen 3 is installed inside the pretreatment cylinder 1, and a stirring mechanism is located below the filter screen 3. A flocculant feeding pipe 4 and a filter aid feeding pipe 5 are installed on the side wall of the pretreatment cylinder 1, positioned between the filter screen 3 and the stirring mechanism. A discharge pipe 6 is installed at the bottom of the pretreatment cylinder 1, and a solenoid valve 7 is installed on the discharge pipe 6. A telescopic hose 8 is connected to the discharge pipe 6. The telescopic hose 8 extends to the inside of the dehydration tank 2. A filter cylinder 9 is rotatably mounted at the bottom of the dehydration tank 2. Multiple filter holes 901 are installed on the side wall of the filter cylinder 9. A centrifugal motor 10 that drives the filter cylinder 9 to rotate is installed at the bottom of the dehydration tank 2. A filter pressing mechanism is installed at the top of the dehydration tank 2, directly opposite the filter cylinder 9. A telescopic mechanism that drives the outlet end of the telescopic hose 8 to move above the filter cylinder 9 is installed on the dehydration tank 2. A drain pipe 19 is provided on one side of the bottom of the dehydration tank 2.

[0017] The stirring mechanism includes a rotating shaft 11 rotatably disposed inside the pretreatment cylinder 1. A rotary motor 12 for driving the rotating shaft 11 to rotate is installed on the outside of the pretreatment cylinder 1. A plurality of stirring blades 13 are fixedly connected to the rotating shaft 11.

[0018] The filter press mechanism includes a hydraulic cylinder 14 installed on the top of the dewatering tank 2. The driving end of the hydraulic cylinder 14 is connected to a filter press plate 15. The filter press plate 15 is positioned directly opposite the filter cylinder 9. The outer diameter of the filter press plate 15 is not greater than the inner diameter of the filter cylinder 9.

[0019] The telescopic mechanism includes an electric telescopic rod 16 installed on the outer wall of the dehydration tank 2. The drive end of the electric telescopic rod 16 is fixedly connected to a fixing plate 17, which is fixedly sleeved at the outlet end of the telescopic hose 8.

[0020] The bottom and side walls of the pretreatment cylinder 1 are embedded with electric heating plates 18. The electric heating plates 18 are set to reduce the viscosity of the waste liquid by heating, which improves the mixing efficiency of the stirring mechanism and reduces the filtration resistance of the subsequent filter cylinder 9.

[0021] In addition, cleaning doors can be installed on the side walls of the dehydration tank 2 and the filter cartridge 9 respectively to facilitate cleaning.

[0022] Working principle:

[0023] Waste water-based drilling fluid is poured into the pretreatment cylinder 1 from the top and filtered through the filter screen 3 to remove impurities such as rock cuttings and fibers. Polyaluminum chloride (PAC) flocculant and diatomaceous earth filter aid are injected through the flocculant feeding pipe 4 and the filter aid feeding pipe 5, respectively. At the same time, the rotary motor 12 is started to drive the rotating shaft 11 and the stirring blades 13 to rotate, so that the agents and waste liquid are fully mixed. During this period, the electric heating plate 18 is started to heat the waste liquid to 30-50℃, reduce the viscosity, and form a flocculent mixture that is easy to dehydrate.

[0024] After pretreatment, start the electric telescopic rod 16, which moves the outlet end of the telescopic hose 8 to directly above the filter cylinder 9 via the fixed plate 17; open the solenoid valve 7, and the flocculent mixture flows into the filter cylinder 9 through the discharge pipe 6 and the telescopic hose 8; start the centrifugal motor 10, which drives the filter cylinder 9 to rotate at high speed, and uses centrifugal force to throw most of the water in the mixture through the filter holes 901 to the bottom of the dewatering tank 2 (the filtrate thrown out can be collected through the drain pipe 19 at the bottom of the dewatering tank 2 for subsequent purification); after centrifugation and pre-dewatering for 10-15 minutes, start the hydraulic cylinder 14, which drives the filter press plate 15 to extend downward into the filter cylinder 9, applying continuous pressure to the centrifuged solid phase, squeezing out the bound water in the solid phase, and completing the deep dewatering after 5-8 minutes of pressure filtration.

[0025] Turn off the centrifugal motor 10 and hydraulic cylinder 14, control the hydraulic cylinder 14 to drive the filter plate 15 to reset, then move the telescopic hose 8 away from the filter cylinder 9 through the telescopic mechanism, and finally open the cleaning door of the dewatering tank 2 to take out the solid mud cake of the filter cylinder 9, thus completing one dewatering operation.

[0026] This invention uses a filter screen 3 to intercept impurities, a stirring mechanism to promote reagent mixing, and an electric heating plate to reduce viscosity, forming a complete pretreatment process of "filtration-reagent action-viscosity adjustment." This avoids impurities clogging subsequent components and ensures sufficient reagent action. The synergistic effect of "centrifugal pre-dehydration + pressure filtration deep dehydration," combined with the reagent action in the pretreatment stage, reduces the moisture content of the solid sludge cake, thereby reducing subsequent transportation and disposal costs and the risk of secondary pollution.

[0027] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A dehydration device for waste water-based drilling fluid, characterized in that: The system includes a pretreatment cylinder (1) and a dewatering tank (2). A filter screen (3) is installed inside the pretreatment cylinder (1), and a stirring mechanism is located below the filter screen (3). A flocculant feeding pipe (4) and a filter aid feeding pipe (5) are installed on the side wall of the pretreatment cylinder (1), located between the filter screen (3) and the stirring mechanism. A discharge pipe (6) is installed at the bottom of the pretreatment cylinder (1), and a solenoid valve (7) is installed on the discharge pipe (6). A telescopic hose (8) is connected to the discharge pipe (6). The filter cylinder (9) is rotatably installed at the bottom of the dehydration tank (2). Multiple filter holes (901) are installed on the side wall of the filter cylinder (9). A centrifugal motor (10) that drives the filter cylinder (9) to rotate is installed at the bottom of the dehydration tank (2). A filter pressing mechanism is installed at the top of the dehydration tank (2) directly opposite the filter cylinder (9). A telescopic mechanism that drives the outlet end of the telescopic hose (8) to move above the filter cylinder (9) is installed on the dehydration tank (2). A drain pipe (19) is provided on one side of the bottom of the dehydration tank (2).

2. The dehydration device for waste water-based drilling fluid as described in claim 1, characterized in that: The stirring mechanism includes a rotating shaft (11) rotatably disposed inside the pretreatment cylinder (1), a rotary motor (12) for driving the rotating shaft (11) to rotate is installed on the outside of the pretreatment cylinder (1), and a plurality of stirring blades (13) are fixedly connected to the rotating shaft (11).

3. The dehydration device for waste water-based drilling fluid as described in claim 1, characterized in that: The filter press mechanism includes a hydraulic cylinder (14) installed on the top of the dewatering tank (2). The driving end of the hydraulic cylinder (14) is connected to a filter press plate (15). The filter press plate (15) is positioned opposite the filter cylinder (9). The outer diameter of the filter press plate (15) is not greater than the inner diameter of the filter cylinder (9).

4. The dehydration device for waste water-based drilling fluid as described in claim 1, characterized in that: The telescopic mechanism includes an electric telescopic rod (16) installed on the outer wall of the dehydration tank (2). The drive end of the electric telescopic rod (16) is fixedly connected to a fixing plate (17), and the fixing plate (17) is fixedly sleeved at the outlet end of the telescopic hose (8).

5. The dehydration device for waste water-based drilling fluid as described in claim 1, characterized in that: The bottom and side walls of the pretreatment cylinder (1) are fitted with electric heating plates (18).

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