Anti-pressure-building device of shale gas produced water sludge treatment system

Abstract

The utility model relates to the technical field of pressure building prevention in sludge conveying, and discloses a pressure building prevention device of a shale gas produced water sludge treatment system, which comprises a sludge return pipeline, and a pneumatic control valve is mounted in the middle section of the sludge return pipeline; a pressure transmitter for monitoring the pressure at the outlet of the screw pump in real time is arranged at the front end, close to the outlet of the screw pump, of the sludge return pipeline; a PLC (Programmable Logic Controller) control box is arranged outside the sludge return pipeline, is in electric signal connection with the pressure transmitter and the pneumatic control valve, and is used for receiving a signal of the pressure transmitter and sending an instruction to control the opening and closing of the pneumatic control valve; the conveying pipeline is further provided with a smashing cavity for smashing sludge cakes, the smashing cavity is arranged at the front end of an inlet of the screw pump, an outlet of the smashing cavity is fixedly connected with the inlet of the screw pump, and an outlet of the sludge backflow pipeline is located at the front end of the inlet of the smashing cavity; the technical problem that in the prior art, a coping scheme adopted for the pressure building condition of a screw pump is high in cost is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of anti-pressure-blocking in sludge transportation, and in particular to an anti-pressure-blocking device for a shale gas produced water sludge treatment system. Background Art

[0002] In sludge treatment systems such as produced water treatment stations, sludge is mainly composed of solid waste generated during the wastewater treatment process, containing a large amount of water and organic matter. It needs to go through a series of treatment steps to reduce its volume and water content for subsequent disposal or utilization.

[0003] In the sludge handling system of a produced water treatment plant, sludge is first collected in a sludge tank. It is then transported via specialized conveying equipment to a membrane filter press for further dewatering. In this process, screw pumps, a commonly used sludge conveying device, are widely used due to their ability to handle high-viscosity media containing solid particles.

[0004] In actual operation, due to the low water content of sludge, the interaction between sludge particles is enhanced, making sludge prone to agglomeration during transportation. When these lumps enter the screw pump system, they are prone to form "bridges" at the pump inlet or inside the pump, that is, the sludge blocks connect to each other to form obstacles, hindering the normal flow of sludge.

[0005] When sludge fluidity deteriorates, the screw pump's workload increases, and the pressure at the pump outlet rises accordingly. If this pressure exceeds the pump's designed tolerance, "pressure buildup" occurs. Pressure buildup not only reduces the screw pump's operating efficiency but can also cause severe wear and even damage to the pump and its associated components, increasing maintenance costs and downtime.

[0006] To address the pressure buildup issue, the produced water treatment station currently employs a manual intervention method. Specifically, a staff member is assigned to monitor the screw pump's operating status in real time, specifically the pressure changes at the pump outlet. If an abnormal pressure increase is detected, indicating pressure buildup, the staff member immediately manually opens the pressure relief valve to return some sludge to the screw pump's inlet, thereby reducing the pressure at the pump outlet.

[0007] However, this approach has significant shortcomings. The probability of pressure buildup is low, and assigning a dedicated staff member to monitor and handle it in real time not only increases labor costs but also wastes too much human resources on such a low-probability event. However, if pressure buildup does occur and is not addressed promptly, it can cause serious damage to the equipment, also resulting in significant cost losses. Utility Model Content

[0008] The utility model aims to provide a device for preventing pressure build-up in a shale gas produced water sludge treatment system, so as to solve the technical problem that the existing technology has high cost in dealing with the pressure build-up of a screw pump.

[0009] To achieve the above-mentioned object, the utility model adopts the following technical solution: a shale gas produced water sludge treatment system anti-pressure holding device, comprising a delivery pipeline for delivering sludge to a filter press, wherein the delivery pipeline uses a screw pump to deliver the sludge, and further comprising a sludge return pipeline, wherein the sludge return pipeline is led out from the outlet end of the screw pump through a tee joint and is connected to the inlet end of the screw pump through another tee joint at the end of the screw pump;

[0010] A pneumatic regulating valve for controlling the connection or disconnection of the sludge return pipeline is installed in the middle section of the sludge return pipeline; a pressure transmitter for real-time monitoring of the pressure at the screw pump outlet is installed at the front end of the sludge return pipeline near the outlet of the screw pump; a PLC control box is installed outside the sludge return pipeline, which is electrically connected to the pressure transmitter and the pneumatic regulating valve. The PLC control box is used to receive the signal from the pressure transmitter and automatically judge and issue instructions to control the opening and closing of the pneumatic regulating valve based on the preset pressure threshold logic;

[0011] The transport pipeline is also provided with a breaking chamber for breaking up sludge agglomerates. The breaking chamber is arranged at the front end of the inlet of the screw pump. The outlet of the breaking chamber is fixedly connected to the inlet of the screw pump. The outlet of the sludge return pipeline is located at the front end of the inlet of the breaking chamber.

[0012] The principles and advantages of this solution are as follows: while the sludge is being transported to the filter press via the screw pump in the delivery pipeline, the pressure transmitter monitors the pressure at the screw pump outlet in real time; once the pressure exceeds the preset pressure threshold, the PLC control box, upon receiving the signal from the pressure transmitter, automatically determines that a pressure buildup has occurred and immediately issues a command to control the opening of the pneumatic regulating valve, allowing the sludge to flow back through the sludge return pipeline to the inlet front end of the crushing chamber; at the same time, due to the setting of the crushing chamber, the sludge is crushed before entering the screw pump, reducing the probability of sludge agglomeration and "bridging"; the returned sludge is mixed with the new sludge and re-enters the crushing chamber, where it is crushed and continues to be transported by the screw pump, thus forming a closed-loop automatic adjustment system;

[0013] Through the electrical signal connection between the PLC control box and the pressure transmitter and pneumatic control valve, automatic detection and pressure relief of pressure buildup are realized without manual intervention, which improves work efficiency and safety; the setting of the breaking chamber effectively reduces the probability of sludge agglomeration and "bridging" phenomenon, reduces the load and wear of the screw pump, and extends the service life of the equipment; through real-time monitoring and automatic pressure relief, the occurrence of pressure buildup is effectively avoided, reducing damage to the screw pump and downtime.

[0014] As an improvement, the crushing chamber is a vertically arranged cylindrical cavity, the height of the crushing chamber is equal to the height of the inlet end of the screw pump, and the diameter of the crushing chamber is greater than the width of the inlet end of the screw pump.

[0015] The beneficial effect of this improvement is that when the sludge enters the crushing chamber, the width of the sludge that can be accommodated in the crushing chamber becomes wider and the space becomes larger; this makes it easier for the sludge to disperse as it is crushed, avoiding the retention of sludge in the crushing chamber; at the same time, the width of the outlet end of the crushing chamber narrows along the arc shape of the inner wall of the cylindrical chamber, allowing the sludge to enter the screw pump more smoothly, further improving the sludge conveying efficiency.

[0016] As an improvement, a transverse stirring assembly for horizontally crushing the sludge and a longitudinal stirring assembly for vertically crushing the sludge are provided in the crushing chamber. The transverse stirring assembly and the longitudinal stirring assembly are arranged in sequence from the inlet end to the outlet end of the crushing chamber. The transverse stirring assembly includes two horizontal rollers arranged horizontally and parallel to each other, and the two horizontal rollers rotate in a relatively inward direction; the longitudinal stirring assembly includes two vertical rollers arranged vertically and parallel to each other, and the two vertical rollers rotate in a relatively outward direction.

[0017] The beneficial effects of this improvement are: the horizontal stirring assembly and the vertical stirring assembly provide horizontal shear force and vertical shear force for crushing in turn, which significantly improves the crushing effect; the sludge may be squeezed inward when passing through the horizontal stirring assembly, and then dispersed outward by the vertical stirring assembly. This coordination method enables the sludge to be fully stirred and dispersed in the crushing chamber; at the same time, the horizontal shear crushing near the inlet is combined with the increase in the width of the inlet, so that the sludge can efficiently enter the crushing chamber, avoiding accumulation and blockage at the inlet; the vertical shear crushing near the outlet is combined with the arc surface of the inner wall of the crushing chamber, so that the sludge can efficiently flow out of the crushing chamber, ensuring the continuity and stability of sludge transportation.

[0018] As an improvement, the horizontal roller and the vertical roller are provided with support rods that are evenly distributed along the circumference of the roller shaft and extend outward. Between the two horizontal rollers or the two vertical rollers, the support rods are staggered along the axial direction of the roller shaft; the length of the support rods is less than the spacing between the two horizontal rollers or the two vertical rollers, and greater than half of the spacing.

[0019] The beneficial effects of this improvement are: the support rods arranged on the horizontal roller and the vertical roller avoid the interference that may be caused by the horizontal roller or the vertical roller directly and effectively stirring; the support rods are evenly distributed along the circumference of the roller shaft and extend outward, and the support rods between the two horizontal rollers or the two vertical rollers are staggered along the axial direction of the roller shaft. This design not only ensures the stirring effect, but also avoids interference and collision between the support rods, thereby improving the stirring efficiency and stability of the crushing chamber.

[0020] As an improvement, a water injection pipeline is connected between the pneumatic regulating valve and the end of the sludge return pipeline in the sludge return pipeline. The water injection pipeline connects the sludge return pipeline with the water supply end. The water injection pipeline is provided with a water injection hole and a solenoid valve for controlling the water output of the water injection hole. The solenoid valve is electrically connected to the PLC control box, and the PLC control box controls the opening and closing and the opening amount of the solenoid valve.

[0021] The beneficial effects of this improvement are: the water injection pipeline connected to the sludge return pipeline increases the fluidity of the sludge by injecting water into the return sludge, avoiding the occurrence of pressure buildup again; at the same time, the sludge after adding water is mixed with normal sludge through the breaking chamber, making the sludge more uniform and further reducing the probability of agglomeration; the PLC control box controls the opening and closing and opening amount of the solenoid valve, realizing precise control of water injection, which not only ensures the pressure relief effect, but also avoids increasing the workload of the subsequent filter press.

[0022] As an improvement, there are multiple water injection holes, and the multiple water injection holes are evenly distributed along the circumference of the sludge return pipeline.

[0023] The beneficial effects of this improvement are: making water injection more uniform, avoiding sludge sticking to the wall of the sludge return pipeline, and improving the smoothness and efficiency of sludge return.

[0024] As an improvement, the outer wall of the sludge return pipeline is wrapped with an insulation layer.

[0025] The beneficial effects of this improvement are: ensuring the temperature stability of the sludge during the reflow process, avoiding changes in sludge properties caused by temperature changes, and improving the efficiency and stability of sludge reflow. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of an embodiment of the present utility model.

[0027] Figure 2 A vertical cross-section of the broken cavity.

[0028] Figure 3 This is a horizontal cross-section of the broken cavity. DETAILED DESCRIPTION

[0029] The following is further described in detail through specific implementation methods:

[0030] The reference numerals in the drawings of the specification include: transport pipeline 1, sludge return pipeline 2, screw pump 3, pneumatic regulating valve 4, pressure transmitter 5, breaking chamber 6, water injection pipeline 7, horizontal stirring assembly 8 and vertical stirring assembly 9.

[0031] Example

[0032] Basically as attached Figure 1As shown, a pressure-blocking prevention device for a shale gas produced water sludge treatment system is provided, which is used on a screw pump 3 for transporting sludge. In this embodiment, the inlet end of the pipeline is called the pipeline front end, and the outlet end of the pipeline is called the pipeline rear end.

[0033] The anti-pressure-holding device includes a transport pipeline 1 and a sludge return pipeline 2. In this embodiment, the transport pipeline 1 uses a screw pump 3 to transport the sludge. The sludge return pipeline 2 is led out from the outlet end of the screw pump 3 through a tee joint, and then connected to the inlet end of the screw pump 3 through a tee joint at the end of the sludge return pipeline 2 to form a closed loop.

[0034] The anti-pressure back-up device also includes a pneumatic regulating valve 4, a pressure transmitter 5 and a PLC control box; in this embodiment, the pneumatic regulating valve 4 adopts a pneumatic butterfly valve with a valve body made of stainless steel. The pneumatic butterfly valve is installed in the middle section of the sludge return pipeline 2. The pneumatic butterfly valve is used to control the connection or disconnection of the sludge water flow pipeline. The pneumatic butterfly valve drives the valve to open and close quickly through compressed air.

[0035] The pressure transmitter 5 is installed at the front end of the sludge return pipeline 2, close to the outlet of the screw pump 3. The pressure transmitter 5 is used to monitor the pump outlet pressure in real time. The pressure transmitter 5 is electrically connected to the PLC control box. The pressure transmitter 5 uses a high-precision pressure sensor, that is, the pressure sensor outputs a 4-20mA signal, which is directly connected to the analog input module of the PLC control box.

[0036] The PLC control box is set next to the sludge return pipeline 2. The PLC control box is connected to the pneumatic control valve 4 by electrical signals. The PLC control box receives the signal from the pressure transmitter 5 and automatically judges and issues instructions to control the opening and closing of the pneumatic control valve 4 according to the preset pressure threshold logic.

[0037] When the screw pump 3 is normally transporting sludge, the pneumatic regulating valve 4 is closed. The sludge flows from the inlet end of the screw pump 3 to the outlet end of the screw pump 3, and the PLC control box continuously monitors the pressure data transmitted by the pressure transmitter 5.

[0038] When it is detected that the outlet pressure of the screw pump 3 exceeds the preset pressure holding threshold, the PLC control box immediately issues an instruction to open the pneumatic regulating valve 4, allowing part of the sludge to enter the sludge return pipeline 2 from the outlet of the screw pump 3, and then flow into the inlet of the screw pump 3 from the sludge return pipeline 2, thereby reducing the outlet pressure of the screw pump 3.

[0039] As attached Figure 2 and attached Figure 3As shown, in order to reduce the occurrence of pressure buildup in the screw pump 3, a breaking chamber 6 is provided at the front end of the inlet of the screw pump 3, the outlet of the breaking chamber 6 is fixedly connected to the inlet of the screw pump 3, and the outlet of the sludge return pipeline 2 is located at the front end of the inlet of the breaking chamber 6; the breaking chamber 6 is a vertically arranged cylindrical cavity, the height of the breaking chamber 6 is equal to the height of the inlet end of the screw pump 3, and the diameter of the breaking chamber 6 is greater than the width of the inlet end of the screw pump 3.

[0040] A transverse stirring assembly 8 and a longitudinal stirring assembly 9 are provided in the crushing chamber 6 , and the transverse stirring assembly 8 and the longitudinal stirring assembly 9 are arranged in sequence from the inlet end to the outlet end of the crushing chamber 6 .

[0041] The horizontal stirring assembly 8 performs preliminary horizontal mixing and crushing of the sludge entering the crushing chamber 6. The horizontal stirring assembly 8 includes two horizontal rollers, which are arranged horizontally and parallel to each other. The two horizontal rollers are driven by a motor to rotate relatively inward, that is, in opposite directions, to achieve interlacing and shearing of the sludge on the horizontal plane. The longitudinal stirring assembly 9 further stirs and refines the sludge in the vertical direction. The longitudinal stirring assembly 9 includes two vertical rollers, which are arranged vertically and parallel to each other. The two vertical rollers are driven by a motor to rotate relatively outward, that is, in opposite directions, to achieve the effect of crushing and mixing the sludge in the vertical direction.

[0042] Both the horizontal and vertical rollers are equipped with outwardly extending support rods evenly distributed along the circumference of the roller shaft. The support rods are staggered along the axial direction between the two horizontal or vertical rollers. The length of the support rods is less than the distance between the two horizontal or vertical rollers, and greater than half the distance between the two horizontal or vertical rollers.

[0043] No matter the sludge is normally transported to enter the screw pump 3 or the sludge is returned from the sludge return pipeline 2 , it must enter the crushing chamber 6 before entering the screw pump 3 .

[0044] A water injection line 7 connects the sludge return line 2 to the water supply, between the pneumatic control valve 4 and the end of the line. This line 7 is equipped with a water injection hole and a solenoid valve for controlling the water output. The solenoid valve is electrically connected to a PLC control box, which controls its opening and closing, as well as the amount of water it opens. Multiple water injection holes are located on the inner surface of the sludge return line 2, arranged in a circle around the circumference of the line.

[0045] When the outlet pressure of the screw pump 3 is detected to exceed the preset pressure holding threshold, the PLC control box decides whether to start the water injection line 7 based on the pressure change rate and degree. The water injection line 7 injects clean water into the return sludge through the water injection hole to increase the sludge fluidity and further relieve the pressure holding.

[0046] The outer wall of the sludge return pipeline 2 is wrapped with a thermal insulation layer to reduce heat loss and sludge coagulation.

[0047] The above description is merely an embodiment of the present invention, and the commonly known specific technical solutions and / or features of the solution are not described in detail here. It should be noted that for those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be considered as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection claimed in this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A device for preventing pressure buildup in a shale gas produced water sludge treatment system, comprising a delivery pipeline for delivering sludge to a filter press, wherein the delivery pipeline utilizes a screw pump to deliver the sludge, and is characterized by: It also includes a sludge return pipeline, which is led out from the outlet end of the screw pump through a tee joint and connected to the inlet end of the screw pump through another tee joint at the end of the screw pump; A pneumatic regulating valve for controlling the connection or disconnection of the sludge return pipeline is installed in the middle section of the sludge return pipeline; a pressure transmitter for real-time monitoring of the pressure at the screw pump outlet is installed at the front end of the sludge return pipeline near the outlet of the screw pump; a PLC control box is installed outside the sludge return pipeline, which is electrically connected to the pressure transmitter and the pneumatic regulating valve. The PLC control box is used to receive the signal from the pressure transmitter and automatically judge and issue instructions to control the opening and closing of the pneumatic regulating valve based on the preset pressure threshold logic; The transport pipeline is also provided with a breaking chamber for breaking up sludge agglomerates. The breaking chamber is arranged at the front end of the inlet of the screw pump. The outlet of the breaking chamber is fixedly connected to the inlet of the screw pump. The outlet of the sludge return pipeline is located at the front end of the inlet of the breaking chamber.

2. The device for preventing pressure buildup in a shale gas produced water sludge treatment system according to claim 1, characterized in that: The crushing chamber is a vertically arranged cylindrical cavity, the height of the crushing chamber is equal to the height of the inlet end of the screw pump, and the diameter of the crushing chamber is greater than the width of the inlet end of the screw pump.

3. The device for preventing pressure buildup in a shale gas produced water sludge treatment system according to claim 2, characterized in that: The crushing chamber is provided with a horizontal stirring assembly for horizontally crushing the sludge and a vertical stirring assembly for vertically crushing the sludge. The horizontal stirring assembly and the vertical stirring assembly are arranged in sequence from the inlet end to the outlet end of the crushing chamber. The horizontal stirring assembly includes two horizontal rollers arranged horizontally and parallel to each other, and the two horizontal rollers rotate in a relatively inward direction; the longitudinal stirring assembly includes two vertical rollers arranged vertically and parallel to each other, and the two vertical rollers rotate in a relatively outward direction.

4. The device for preventing pressure buildup in a shale gas produced water sludge treatment system according to claim 3, characterized in that: The horizontal rollers and the vertical rollers are both provided with support rods that are evenly distributed along the circumference of the roller shaft and extend outward. Between the two horizontal rollers or the two vertical rollers, the support rods are staggered along the axial direction of the roller shaft; the length of the support rods is less than the spacing between the two horizontal rollers or the two vertical rollers, and greater than half of the spacing.

5. The device for preventing pressure buildup in a shale gas produced water sludge treatment system according to claim 4, characterized in that: A water injection pipeline is connected in the sludge return pipeline between the pneumatic regulating valve and the end of the sludge return pipeline. The water injection pipeline connects the sludge return pipeline with the water supply end. The water injection pipeline is provided with a water injection hole and a solenoid valve for controlling the water output of the water injection hole. The solenoid valve is connected to the PLC control box with an electrical signal, and the PLC control box controls the opening and closing and the opening amount of the solenoid valve.

6. The device for preventing pressure buildup in a shale gas produced water sludge treatment system according to claim 5, characterized in that: There are multiple water injection holes, and the multiple water injection holes are evenly distributed along the circumference of the sludge return pipeline.

7. The device for preventing pressure buildup in a shale gas produced water sludge treatment system according to claim 6, characterized in that: The outer wall of the sludge return pipeline is wrapped with a thermal insulation layer.

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