Evaporative crystallization cycle control device for inhibiting salt scale formation

Abstract

This invention discloses an evaporation crystallization circulation control device for inhibiting scale formation, belonging to the field of industrial crystallization technology. It includes a crystallization evaporation chamber, a heat exchanger, a forced circulation pump, a lower circulation pipe, a raw slurry inlet, a delivery pipe, and an upper circulation pipe. It also includes a transmission mechanism, a flow regulation mechanism, and a seed crystal addition mechanism. This invention utilizes a flow regulation mechanism consisting of a flow valve, a push-pull rod, and a connecting rod at the lower circulation pipe and the raw slurry inlet. This mechanism is linked with a transmission mechanism consisting of a crossbar, a sliding rod, a cone block, a first cylinder, a first piston, and a return spring. By varying the force exerted on the cone block by changes in the circulating fluid flow rate, the movement of the first piston inside the first cylinder is controlled. The return spring provides a reset force, controlling the flow of the medium inside the first and second cylinders. Furthermore, the push-pull rod and connecting rod regulate the flow valve to adjust the saturation of the circulating fluid and the circulation rate, thus preventing scale formation.

Description

Technical Field

[0001] This invention relates to an evaporation crystallization cycle control device, and more particularly to an evaporation crystallization cycle control device for inhibiting scale formation, belonging to the field of industrial crystallization technology. Background Technology

[0002] Forced circulation crystallizers are widely used in the evaporation and crystallization treatment of high-concentration saline wastewater. Their core working principle is to rely on a forced circulation pump to drive the crystal slurry to circulate between the heating chamber and the crystallization separation chamber. The high-speed fluid scouring action on the heat exchange tube wall inhibits the adhesion and growth of crystals on the heat exchange surface, thereby ensuring the long-term stable operation of the equipment.

[0003] However, in actual operation, when the supersaturation of the solution in the crystallizer continues to increase, the system circulation resistance increases significantly. Under the premise that the input power of the circulation pump is relatively fixed, the circulation flow rate will fluctuate significantly or even continue to decrease. After the flow rate decreases, the supersaturated solute is very likely to induce crystals to adhere and grow in large quantities on the heat exchange tube wall and the inner wall of the circulation pipeline, eventually forming a dense scale layer.

[0004] Currently, to address the aforementioned issues, complex electronic control systems are used to adjust parameters such as feed rate, discharge rate, and circulating pump frequency in order to maintain system stability. However, in the instant when supersaturation suddenly increases and flow rate drops sharply, the lag in adjustment by the electronic control system can easily lead to control failure. In addition, the complex electronic control system increases equipment investment and operating costs.

[0005] To address this issue, an evaporation-crystallization circulation control device was designed to suppress scale formation and optimize the aforementioned problem. Summary of the Invention

[0006] The main objective of this invention is to provide an evaporation crystallization cycle control device for inhibiting scale formation, thereby solving the problems mentioned in the background art.

[0007] The objective of this invention can be achieved by adopting the following technical solution: An evaporation crystallization circulation control device for inhibiting scale formation includes a crystallization evaporation chamber, a heat exchanger, a forced circulation pump, a lower circulation pipe, a raw slurry inlet, a delivery pipe, and an upper circulation pipe; It also includes a transmission mechanism, a flow regulation mechanism, and a seed crystal addition mechanism; The transmission mechanism is mounted on the delivery pipe and is used to sense the physical changes in the flow rate of the circulating liquid in the delivery pipe and output mechanical driving force. The flow regulation mechanism is installed on the raw pulp inlet and the lower circulation pipe, and is mechanically linked with the transmission mechanism to synchronously adjust the flow opening of the raw pulp inlet and the lower circulation pipe according to the change in flow velocity. The seed crystal adding mechanism is located at the top of the lower circulation tube and is mechanically linked with the transmission mechanism to add seed crystals into the lower circulation tube according to changes in flow rate.

[0008] Preferably, the transmission mechanism includes a crossbar fixed to the inner wall of the conveying pipe, a slide rod vertically slidably disposed on the crossbar, a cone block fixed on the slide rod, a first piston disposed at the top of the slide rod, a first cylinder housing the first piston, and a second cylinder communicating with the interior of the first cylinder. The first cylinder is fixed to the top of the crossbar, and a return spring is provided inside the first cylinder. The two ends of the return spring abut against the first piston and the inner end face of the first cylinder, respectively. The second cylinder is installed on the side of the lower circulation pipe. A guide pipe is connected between the first cylinder and the second cylinder. A second piston is provided inside the second cylinder, and a push rod is fixed on the second piston. A fixing frame is provided between the second cylinder body and the outer wall of the lower circulation pipe, and a strip groove is provided on the fixing frame. A guide rod is slidably provided inside the strip groove, and the end of the push rod is fixedly connected to the guide rod.

[0009] Preferably, the open end of the first cylinder faces the cone block, and a filter plate is provided at the open end of the first cylinder, with the slide rod passing through the filter plate and slidably connected to it.

[0010] Preferably, the first cylinder and the second cylinder are filled with hydraulic oil or gas medium. When the cone block is displaced by the impact of the circulating fluid flow, the first piston moves, causing the internal volume of the first cylinder to change, which drives the second piston and the push rod to move through the guide pipe.

[0011] Preferably, the flow regulating mechanism includes flow valves disposed on the raw pulp inlet and the lower circulation pipe, a push-pull rod and a connecting rod connecting the guide rod and the two flow valves, wherein the guide rod is mechanically connected to the valve cores of the two flow valves through the push-pull rod and the connecting rod.

[0012] Preferably, the top end of the push-pull rod is fixedly connected to the valve core drive shaft of the flow valve, the bottom end of the push-pull rod is hinged to the end of the connecting rod, and the end of the connecting rod away from the push-pull rod is fixedly connected to the guide rod.

[0013] Preferably, the seed crystal adding mechanism includes a seed crystal box fixed to the top of the lower circulation tube, a seed crystal adding tube connected to the bottom of the seed crystal box and communicating with the inside of the lower circulation tube, a gate valve disposed on the seed crystal adding tube, and a vertical rod connected between the gate valve plate and the push rod.

[0014] Preferably, the lower circulation pipe is further provided with a spiral conveying blade, which is fixed to the inner wall at the bottom of the lower circulation pipe to guide the raw slurry and the circulating liquid to mix evenly.

[0015] Preferably, a guide plate is also provided inside the lower circulation pipe, and the guide plate is located at the top of the lower circulation pipe to guide the circulating fluid to rotate and flow.

[0016] The beneficial effects of this invention are as follows: This invention provides an evaporation crystallization circulation control device for inhibiting scale formation. It comprises a flow regulating mechanism consisting of a flow valve, a push-pull rod, and a connecting rod installed at the lower circulation pipe and the raw slurry inlet. This mechanism is linked with a transmission mechanism consisting of a crossbar, a slide rod, a cone block, a first cylinder, a first piston, and a return spring. By varying the force applied to the cone block by changes in the circulating fluid flow rate, the movement of the first piston inside the first cylinder is controlled. The return spring provides a reset force, controlling the flow of the medium inside the first and second cylinders. Furthermore, the push-pull rod and connecting rod regulate the flow valve to adjust the saturation of the circulating fluid, thereby adjusting the circulation flow rate and preventing scale formation. By setting a seed addition mechanism consisting of a seed box, a seed addition tube, a gate valve, and a vertical rod at the top of the lower circulation pipe, this mechanism is also purely mechanically linked with the transmission mechanism. When the flow rate decreases and triggers the transmission mechanism, the displacement of the second piston drives the vertical rod to move synchronously through the push rod, which in turn opens the gate valve, so that the seed crystals in the seed box are automatically and quantitatively added into the crystal slurry of the lower circulation pipe through the seed addition tube. This provides a growth substrate for the preferential precipitation of supersaturated solutes and also avoids the adhesion and growth of scale on the wall surface. Attached Figure Description

[0017] Figure 1 This is a front view schematic diagram of the present invention; Figure 2 This is a schematic diagram of the back of the present invention; Figure 3 This is a schematic cross-sectional view of the lower circulation pipe and the delivery pipe of the present invention; Figure 4 This is a schematic diagram of the overall transmission mechanism of the present invention; Figure 5 This is a schematic cross-sectional view of the inside of the delivery pipe of the present invention; Figure 6 This is a schematic cross-sectional view of the second cylinder block of the present invention; Figure 7 This is a schematic diagram of the seed crystal addition mechanism of the present invention.

[0018] In the diagram: 1. Crystallization evaporation chamber; 2. Heat exchanger; 3. Forced circulation pump; 4. Lower circulation pipe; 5. Raw pulp inlet; 6. Delivery pipe; 7. Upper circulation pipe; 8. Transmission mechanism; 801. Crossbar; 802. Slide rod; 803. Conical block; 804. First cylinder; 805. First piston; 806. Return spring; 807. Filter plate; 808. Second cylinder; 809. Guide pipe; 810. Second piston; 811. Push rod; 812. Fixing frame; 813. Strip groove; 814. Guide rod; 9. Flow regulating mechanism; 901. Flow valve; 902. Push-pull rod; 903. Connecting rod; 10. Seed crystal addition mechanism; 1001. Seed crystal box; 1002. Seed crystal addition tube; 1003. Slide valve; 1004. Vertical rod; 11. Spiral conveyor blades; 12. Guide vane. Detailed Implementation

[0019] To enable those skilled in the art to more clearly understand the technical solution of the present invention, the present invention will be further described in detail below with reference to embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0020] Example 1: As Figures 1-7 As shown, this embodiment provides an evaporation crystallization circulation control device for inhibiting scale formation, including a crystallization evaporation chamber 1, a heat exchanger 2, a forced circulation pump 3, a lower circulation pipe 4, a raw slurry inlet 5, a delivery pipe 6, and an upper circulation pipe 7; It also includes a transmission mechanism 8, a flow regulation mechanism 9, and a seed crystal addition mechanism 10; The transmission mechanism 8 is installed on the delivery pipe 6 and is used to sense the physical changes in the flow rate of the circulating liquid in the delivery pipe 6 and output mechanical driving force. The flow regulation mechanism 9 is installed on the raw pulp inlet 5 and the lower circulation pipe 4, and is mechanically linked with the transmission mechanism 8. It is used to synchronously adjust the flow opening of the raw pulp inlet 5 and the lower circulation pipe 4 according to the change in flow rate. The seed crystal adding mechanism 10 is located at the top of the lower circulation pipe 4 and is mechanically linked with the transmission mechanism 8. It is used to add seed crystals into the lower circulation pipe 4 according to the change in flow rate.

[0021] Under normal and stable operating conditions, the forced circulation pump 3 drives the crystal slurry to circulate along the circulation pipeline: the crystal slurry is discharged from the bottom of the crystallization evaporation chamber 1 through the lower circulation pipe 4, and after being pressurized by the forced circulation pump 3, it is sent to the tube side of the heat exchanger 2 through the delivery pipe 6. After being heated in the heat exchanger 2, the crystal slurry returns to the crystallization evaporation chamber 1 through the upper circulation pipe 7, where flash crystallization occurs, completing one cycle. During this process, the high-speed flowing crystal slurry continuously scours the inner wall of the heat exchange tubes and the inner wall of the circulation pipeline of the heat exchanger 2, effectively inhibiting the adhesion and growth of crystals on the wall surface.

[0022] When the supersaturation of the solution in the crystallization evaporation chamber 1 continues to increase, a large number of crystals undergo explosive nucleation within a short period of time, causing a sharp increase in the apparent viscosity of the solid-liquid two-phase flow of the crystal slurry and a significant rise in circulation resistance. Under the premise that the input power of the forced circulation pump 3 is relatively fixed, the flow rate of the circulating liquid in the circulation pipeline will decrease significantly. At this time, the transmission mechanism 8, installed on the delivery pipe 6, senses this physical change in flow rate in real time and outputs this change in the form of mechanical displacement, synchronously transmitting it to the flow regulation mechanism 9 and the seed crystal addition mechanism 10.

[0023] After receiving the mechanical driving force from the transmission mechanism 8, the flow regulating mechanism 9 operates synchronously: on the one hand, it closes the flow valve 901 set at the raw slurry inlet 5 to reduce the amount of fresh high-concentration sewage entering, thereby suppressing the input of total salt in the system from the source and curbing the further rise of supersaturation; on the other hand, it adjusts the opening of the flow valve 901 set on the lower circulation pipe 4 to optimize the resistance characteristics of the circulation loop, assist in stabilizing the operating point of the forced circulation pump 3, and delay the decline of flow rate.

[0024] Simultaneously, the seed crystal addition mechanism 10 also receives mechanical driving force from the transmission mechanism 8, automatically opening the seed crystal addition tube 1002 located at the top of the lower circulation pipe 4, and quantitatively adding the seed crystals from the seed crystal box 1001 into the crystal slurry inside the lower circulation pipe 4. The added seed crystals provide a growth substrate for the preferential precipitation of supersaturated solutes, and the crystallization driving force is transferred from the heat exchange tube wall and circulation pipe wall to the surface of the suspended seed crystals, effectively preventing the adhesion and growth of scale on the wall surface.

[0025] When the circulation flow rate returns to the normal level, the transmission mechanism 8 automatically resets, and the flow regulation mechanism 9 and the seed crystal addition mechanism 10 return to their initial state. The entire control process is achieved entirely by pure mechanical transmission without any external electrical control signal intervention.

[0026] Example 2: The solution in Example 1 will be further described below with reference to its specific working method. See the description below for details: In this embodiment, the transmission mechanism 8 includes a crossbar 801 fixed to the inner wall of the conveying pipe 6, a slide rod 802 vertically slidably disposed on the crossbar 801, a cone block 803 fixed on the slide rod 802, a first piston 805 disposed at the top of the slide rod 802, a first cylinder 804 accommodating the first piston 805, and a second cylinder 808 communicating with the interior of the first cylinder 804. The first cylinder 804 is fixed to the top of the crossbar 801, and a return spring 806 is provided inside the first cylinder 804. The two ends of the return spring 806 abut against the first piston 805 and the inner end face of the first cylinder 804, respectively. The second cylinder 808 is installed on the side of the lower circulation pipe 4. A guide pipe 809 is connected between the first cylinder 804 and the second cylinder 808. A second piston 810 is provided inside the second cylinder 808. A push rod 811 is fixed on the second piston 810. A fixing bracket 812 is provided between the second cylinder body 808 and the outer wall of the lower circulation pipe 4, and a strip groove 813 is provided on the fixing bracket 812. A guide rod 814 is slidably provided inside the strip groove 813, and the end of the push rod 811 is fixedly connected to the guide rod 814.

[0027] When the forced circulation pump 3 is operating normally, the circulating fluid flows through the inside of the delivery pipe 6 at the designed flow rate. The cone block 803 is fixed to the bottom of the slide rod 802 and extends into the inside of the delivery pipe 6. The conical frontal surface of the cone block 803 continuously bears the impact force generated by the flow of the circulating fluid. The magnitude of this impact force is proportional to the square of the circulating fluid velocity: the higher the velocity, the greater the impact force; when the velocity decreases, the impact force decreases accordingly.

[0028] When the circulating fluid flow rate decreases due to increased supersaturation, the impact force on the cone block 803 decreases accordingly. Under the reset action of the return spring 806, the first piston 805 pushes the cone block 803 downward by a certain displacement via the slide rod 802. The slide rod 802 slides vertically along the crossbar 801, ensuring the accuracy of the movement direction.

[0029] When the first piston 805 moves downward inside the first cylinder 804, the first cylinder 804 draws medium from inside the second cylinder 808 and pulls the second piston 810 and the push rod 811 fixed thereon to retract inward. The end of the push rod 811 is fixedly connected to the guide rod 814, which slides along the fixed frame 812 under the constraint of the strip groove 813, thereby outputting the change in flow rate sensed by the transmission mechanism 8 outward in the form of mechanical displacement.

[0030] When the circulating flow rate increases, the impact force on the cone block 803 increases, pushing the slide rod 802 and the first piston 805 to move upward against the elastic force of the return spring 806, and the medium flows back to the second cylinder 808. The second piston 810 and the push rod 811 automatically extend and reset.

[0031] In this embodiment, the open end of the first cylinder 804 faces the cone block 803, and a filter plate 807 is provided at the open end of the first cylinder 804. The slide rod 802 passes through the filter plate 807 and is slidably connected to it.

[0032] The filter plate 807 isolates the circulating liquid inside the delivery pipe 6 from the inside of the first cylinder 804, preventing solid particles in the circulating liquid from entering the inside of the first cylinder 804, avoiding failure of the first piston 805 due to particle wear or jamming, and ensuring the long-term reliable operation of the transmission mechanism 8.

[0033] In this embodiment, the first cylinder 804 and the second cylinder 808 are filled with hydraulic oil or gas medium. When the cone block 803 is displaced by the impact of the circulating fluid flow, the first piston 805 moves, causing the internal volume of the first cylinder 804 to change. This changes the second piston 810 and the push rod 811 through the guide pipe 809.

[0034] Using hydraulic oil or gas as the transmission medium offers advantages such as fast response, gapless transmission, and long-distance drive force transmission. By rationally selecting the inner diameter ratio of the first cylinder 804 to the second cylinder 808, the displacement can be amplified or reduced to meet the matching requirements of the flow valve 901's adjustment stroke and the amount of seed crystals added under different working conditions.

[0035] In this embodiment, the flow regulating mechanism 9 includes a flow valve 901 disposed on the raw pulp inlet 5 and the lower circulation pipe 4, a push-pull rod 902 and a connecting rod 903 connected between the guide rod 814 and the two flow valves 901, and the guide rod 814 is mechanically connected to the valve core of the two flow valves 901 through the push-pull rod 902 and the connecting rod 903.

[0036] In this embodiment, the top end of the push-pull rod 902 is fixedly connected to the valve core drive shaft of the flow valve 901, the bottom end of the push-pull rod 902 is hinged to the end of the connecting rod 903, and the end of the connecting rod 903 away from the push-pull rod 902 is fixedly connected to the guide rod 814.

[0037] When the push rod 811 of the transmission mechanism 8 is pulled inward and extended outward, the guide rod 814 slides horizontally along the strip groove 813. The guide rod 814 drives the push-pull rod 902 to move through the fixedly connected connecting rod 903. The push-pull rod 902 then drives the valve core drive shaft of the flow valve 901 to rotate, thereby changing the opening degree of the flow valve 901.

[0038] Specifically, the flow valve 901, located at the raw slurry inlet 5, is closed slightly by the push-pull rod 902, reducing the amount of fresh, high-concentration wastewater entering the system. With the reduced raw slurry intake, the total salt input to the system decreases, and the supersaturation inside the crystallization evaporation chamber 1 is contained due to the lack of new solute replenishment. Combined with the continued evaporation and crystallization process, the supersaturation gradually returns to a safe range.

[0039] Meanwhile, the flow valve 901 installed on the lower circulation pipe 4 is also adjusted accordingly under the drive of the push-pull rod 902, changing the local resistance characteristics of the lower circulation pipe 4, and adjusting the flow rate of the circulating liquid flowing through the forced circulation pump 3 to a certain extent, so that the forced circulation pump 3 can still maintain operation in the high-efficiency working range under the changed working conditions.

[0040] In this embodiment, the seed addition mechanism 10 includes a seed box 1001 fixed to the top of the lower circulation pipe 4, a seed addition pipe 1002 connected to the bottom of the seed box 1001 and communicating with the interior of the lower circulation pipe 4, a gate valve 1003 disposed on the seed addition pipe 1002, and a vertical rod 1004 connected between the valve plate of the gate valve 1003 and the push rod 811.

[0041] A certain amount of seed crystals are pre-stored inside the seed box 1001. When the push rod 811 of the transmission mechanism 8 retracts inward, the slide valve 1003 is opened in conjunction with the vertical rod 1004, so that the seed crystals inside the seed box 1001 automatically fall into the lower circulation pipe 4 through the seed addition pipe 1002 under the action of gravity, and mix with the crystal slurry flowing through the lower circulation pipe 4.

[0042] The amount of retraction of push rod 811 corresponds to the decrease in flow rate. Therefore, the opening degree of slide valve 1003 is proportional to the decrease in flow rate: the greater the decrease in flow rate, the greater the retraction of push rod 811, the greater the opening degree of slide valve 1003, and the more seed crystals are added accordingly; conversely, when the decrease in flow rate is small, the amount of seed crystals added is also reduced accordingly, thus realizing quantitative addition as needed.

[0043] After the seed crystals enter the lower circulation pipe 4, they flow with the crystal slurry in the circulation pipe and eventually enter the crystallization evaporation chamber 1. The large number of suspended seed crystals provides sufficient precipitation growth surface for the supersaturated solute. The supersaturated solute preferentially grows on the seed crystal surface, rather than adhering to the inner wall of the heat exchange tube of heat exchanger 2 and the inner wall of the circulation pipe to form scale. This achieves the goal of inhibiting scale formation from a physicochemical perspective.

[0044] When the circulation flow rate increases, the push rod 811 extends outward and closes the slide valve 1003 through the vertical rod 1004, stopping the addition of seed crystals and preventing excessive addition of seed crystals from causing the slurry density to be too high.

[0045] In this embodiment, a spiral conveying blade 11 is also provided inside the lower circulation pipe 4. The spiral conveying blade 11 is fixed on the inner wall at the bottom of the lower circulation pipe 4 and is used to guide the raw slurry and circulating liquid to mix evenly.

[0046] When the raw pulp enters the lower circulation pipe 4 through the raw pulp inlet 5, it encounters the existing circulating crystal pulp in the lower circulation pipe 4. The spiral conveying blades 11 extend the mixing time to ensure uniform mixing.

[0047] In this embodiment, a guide plate 12 is also provided inside the lower circulation pipe 4. The guide plate 12 is located at the top of the lower circulation pipe 4 and is used to guide the circulating liquid to rotate and flow.

[0048] The crystal slurry discharged from the crystallization evaporation chamber 1 is guided into the lower circulation pipe 4 in a rotating state to improve the flushing effect on the inner wall of the lower circulation pipe 4 and avoid scale formation on the pipe wall.

[0049] The solutions in Embodiment 1 and Embodiment 2 will be further described below with reference to their specific working methods. Under normal operating conditions, the forced circulation pump 3 drives the crystal slurry to flow stably in the circulation pipeline at the designed flow rate. The cone block 803 withstands a significant impact force from the high-speed circulating liquid. This impact force is transmitted to the first piston 805 via the slide rod 802, overcoming the elastic force of the return spring 806 and keeping the return spring 806 in a fully compressed state. The first piston 805 is located at the uppermost position inside the first cylinder 804, while the second piston 810 and push rod 811 are in their extended working positions. At this time, the flow valve 901 on the raw slurry inlet 5 maintains its normal opening to ensure the designed feed rate; the flow valve 901 on the lower circulation pipe 4 maintains its designed opening, and the circulation loop resistance is at the designed level; the slide valve 1003 is closed, and no seed crystals are added.

[0050] When the supersaturation of the solution in the crystallization evaporation chamber 1 increases, leading to an increase in the viscosity of the circulating liquid and a decrease in the circulating flow rate, the impact force on the cone block 803 decreases. When the impact force is insufficient to overcome the elastic force of the return spring 806, the return spring 806 releases from its maximum compression state and pushes the first piston 805 downward. The downward movement of the first piston 805 increases the internal volume of the first cylinder 804, creating a negative pressure. This negative pressure draws the medium from the second cylinder 808 through the guide pipe 809, pulling the second piston 810 and the push rod 811 inward. The retraction of the push rod 811 simultaneously drives two actions: Firstly, the push rod 811 drives the flow valve 901 to operate in conjunction with the guide rod 814, the connecting rod 903, and the push-pull rod 902: the flow valve 901, located on the raw pulp inlet 5, closes its opening to reduce the raw pulp feed rate and control the total salt input in the system from the source; the flow valve 901, located on the lower circulation pipe 4, adjusts its opening synchronously to optimize the resistance characteristics of the circulation loop and help stabilize the operating point of the forced circulation pump 3.

[0051] Secondly, the push rod 811 opens the slide valve 1003 in conjunction with the vertical rod 1004, so that the crystal seeds in the seed box 1001 fall quantitatively into the circulating liquid inside the lower circulation pipe 4 through the seed addition tube 1002, providing a growth substrate for the preferential precipitation of supersaturated solute, and shifting the crystallization driving force from the wall surface to the surface of the suspended crystal seeds.

[0052] When the circulation rate returns to normal, the impact force on the cone block 803 increases, pushing the slide rod 802 and the first piston 805 upwards against the elastic force of the return spring 806. The first piston 805 pushes the medium in the first cylinder 804 back to the second cylinder 808 through the guide pipe 809, pushing the second piston 810 and push rod 811 outwards to reset. The return spring 806 is then compressed back to its maximum compression state. The flow valve 901 returns to its initial opening, and the slide valve 1003 automatically closes, stopping the addition of seed crystals.

[0053] The above description is merely a further embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope disclosed in the present invention, based on the technical solution and concept of the present invention, shall fall within the scope of protection of the present invention.

Claims

1. An evaporation crystallization circulation control device for inhibiting scale formation, comprising a crystallization evaporation chamber (1), a heat exchanger (2), a forced circulation pump (3), a lower circulation pipe (4), a raw slurry inlet (5), a conveying pipe (6), and an upper circulation pipe (7), characterized in that: It also includes a transmission mechanism (8), a flow regulation mechanism (9), and a seed crystal addition mechanism (10). The transmission mechanism (8) is disposed on the conveying pipe (6) and is used to sense the physical change of the flow rate of the circulating liquid in the conveying pipe (6) and output mechanical driving force. The flow regulation mechanism (9) is installed on the raw pulp inlet (5) and the lower circulation pipe (4) and is mechanically linked with the transmission mechanism (8) to synchronously adjust the flow opening of the raw pulp inlet (5) and the lower circulation pipe (4) according to the flow rate change; The seed crystal adding mechanism (10) is located at the top of the lower circulation pipe (4) and is mechanically linked with the transmission mechanism (8) to add seed crystals into the lower circulation pipe (4) according to the change in flow rate.

2. The evaporation and crystallization circulation control device for inhibiting scale formation according to claim 1, characterized in that: The transmission mechanism (8) includes a crossbar (801) fixed to the inner wall of the conveying pipe (6), a slide rod (802) vertically slidably disposed on the crossbar (801), a cone block (803) fixed on the slide rod (802), a first piston (805) disposed at the top of the slide rod (802), a first cylinder (804) accommodating the first piston (805), and a second cylinder (808) communicating with the interior of the first cylinder (804). The first cylinder (804) is fixed to the top of the crossbar (801), and a return spring (806) is provided inside the first cylinder (804). The two ends of the return spring (806) abut against the first piston (805) and the inner end face of the first cylinder (804), respectively. The second cylinder (808) is installed on the side of the lower circulation pipe (4), and a guide pipe (809) is connected between the first cylinder (804) and the second cylinder (808). A second piston (810) is provided inside the second cylinder (808), and a push rod (811) is fixed on the second piston (810). A fixing frame (812) is provided between the second cylinder body (808) and the outer wall of the lower circulation pipe (4), and a strip groove (813) is provided on the fixing frame (812). A guide rod (814) is slidably provided inside the strip groove (813), and the end of the push rod (811) is fixedly connected to the guide rod (814).

3. The evaporation and crystallization circulation control device for inhibiting scale formation according to claim 2, characterized in that: The open end of the first cylinder (804) faces the cone block (803), and a filter plate (807) is provided at the open end of the first cylinder (804). The slide rod (802) passes through the filter plate (807) and is slidably connected to it.

4. The evaporation and crystallization circulation control device for inhibiting scale formation according to claim 2, characterized in that: The first cylinder (804) and the second cylinder (808) are filled with hydraulic oil or gas medium. When the cone block (803) is displaced by the impact of the circulating fluid flow, the first piston (805) moves, causing the volume of the first cylinder (804) to change. The second piston (810) and the push rod (811) are driven to move through the guide pipe (809).

5. The evaporation and crystallization circulation control device for inhibiting scale formation according to claim 2, characterized in that: The flow regulating mechanism (9) includes a flow valve (901) disposed on the raw pulp inlet (5) and the lower circulation pipe (4), a push-pull rod (902) and a connecting rod (903) connected between the guide rod (814) and the two flow valves (901), and the guide rod (814) is mechanically connected to the valve core of the two flow valves (901) through the push-pull rod (902) and the connecting rod (903).

6. The evaporation and crystallization circulation control device for inhibiting scale formation according to claim 5, characterized in that: The top end of the push-pull rod (902) is fixedly connected to the valve core drive shaft of the flow valve (901), the bottom end of the push-pull rod (902) is hinged to the end of the connecting rod (903), and the end of the connecting rod (903) away from the push-pull rod (902) is fixedly connected to the guide rod (814).

7. The evaporation and crystallization circulation control device for inhibiting scale formation according to claim 2, characterized in that: The seed addition mechanism (10) includes a seed box (1001) fixed to the top of the lower circulation pipe (4), a seed addition pipe (1002) connected to the bottom of the seed box (1001) and communicating with the interior of the lower circulation pipe (4), a slide valve (1003) provided on the seed addition pipe (1002), and a vertical rod (1004) connected between the valve plate of the slide valve (1003) and the push rod (811).

8. The evaporation and crystallization circulation control device for inhibiting scale formation according to claim 1, characterized in that: The lower circulation pipe (4) is also provided with a spiral conveying blade (11), which is fixed on the inner wall at the bottom of the lower circulation pipe (4) to guide the raw slurry and circulating liquid to mix evenly.

9. The evaporation and crystallization circulation control device for inhibiting scale formation according to claim 1, characterized in that: The lower circulation pipe (4) is also provided with a guide plate (12), which is located at the top of the lower circulation pipe (4) and is used to guide the circulating liquid to rotate and flow.

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