Lime slurry preparation system suitable for garbage power plant

Abstract

The lime slurry preparation system comprises a slaked lime bin, a slurry preparation tank, a distribution tank, a settling pond and a water supply main pipe, the feeding end of the slurry preparation tank is connected with the slaked lime bin and the water supply main pipe through pipelines, the discharging end of the slurry preparation tank is connected with the distribution tank through a pipeline, and the settling pond is connected with the distribution tank through a pipeline. The discharge end of the distribution tank is connected to a deacidification reaction tower of the garbage incinerator through a pipeline; the settling pond is used for collecting lime slurry waste liquid generated by a lime slurry preparation system, a lifting pump is arranged in the settling pond, an inlet filter screen and an outlet filter screen are arranged on an inlet pipeline and an outlet pipeline of the lifting pump respectively, and the outlet pipeline of the lifting pump is connected with the feeding end of the slurry preparation tank through a slurry recycling pipe; and the lifting pump is used for recycling the lime slurry waste liquid collected in the sedimentation tank into the slurrying tank. The device has the characteristics of compact structure, convenience in operation, high stability and the like, and lime slurry waste liquid collected in the sedimentation tank is effectively reused.

Description

Technical Field

[0001] This utility model relates to the field of waste incineration flue gas treatment technology, specifically to a lime slurry preparation system suitable for waste-to-energy plants. Background Technology

[0002] Currently, most waste incinerator flue gas treatment systems use semi-dry deacidification towers to treat acidic gases, which inevitably generates lime slurry waste liquid during the process. Waste-to-energy plants commonly treat lime slurry waste liquid using the following methods:

[0003] (1) Neutralization treatment: neutralize the alkaline components in the lime slurry waste liquid with acidic substances. For example, add an appropriate amount of waste acid to neutralize the waste liquid so that the pH value is close to neutral, which can reduce its alkaline hazards.

[0004] (2) Sedimentation separation: Flocculants, such as polyaluminum chloride, are added to the lime slurry waste liquid. The flocculants cause the suspended solid particles in the waste liquid to aggregate and form larger precipitates. The solids are separated by sedimentation, filtration and other methods. The separated solids can be further treated by landfill, and the filtrate is then treated according to its composition.

[0005] (3) Evaporation crystallization: For lime slurry waste liquid whose main components are crystallizable substances such as calcium hydroxide, the water content is reduced by evaporation, so that the solute crystallizes out. The resulting crystallized substance can be recycled, for example, for use in the production of building materials.

[0006] Existing methods for treating lime slurry waste liquid are neither able to effectively utilize the lime slurry present in the waste liquid, nor do they have the drawback of high treatment costs. Utility Model Content

[0007] The technical problem to be solved by this utility model is to overcome the shortcomings of existing lime slurry waste liquid treatment, such as high cost and ineffective recycling of lime slurry, and to provide a lime slurry preparation system that is compact, easy to operate, highly stable and low cost, suitable for waste-to-energy plants.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0009] A lime slurry preparation system suitable for waste-to-energy plants includes: a slaked lime silo, a slurry preparation tank, a distribution tank, a sedimentation tank, and a main water supply pipe. The inlet end of the slurry preparation tank is connected to the slaked lime silo and the main water supply pipe via pipes, and the outlet end of the slurry preparation tank is connected to the distribution tank via a pipe. The outlet end of the distribution tank is connected to the deacidification reaction tower of the waste incinerator via a pipe. The sedimentation tank is used to collect lime slurry waste liquid generated by the lime slurry preparation system, and a booster pump is installed in the sedimentation tank. The inlet and outlet pipes of the booster pump are respectively equipped with inlet and outlet filters, and the outlet pipe of the booster pump is connected to the inlet end of the slurry preparation tank via a slurry recycling pipe. The booster pump is used to recycle the lime slurry waste liquid collected in the sedimentation tank back to the slurry preparation tank.

[0010] As a further improvement of this utility model, the sedimentation tank is equipped with a level gauge, and the side wall of the sedimentation tank is respectively equipped with a high liquid level point and a low liquid level point; the lift pump is linked with the level gauge. When the level gauge detects that the lime slurry waste liquid in the sedimentation tank is at the high liquid level point, the lift pump starts; when the level gauge detects that the lime slurry waste liquid in the sedimentation tank is at the low liquid level point, the lift pump stops running.

[0011] As a further improvement of this utility model, the liquid level gauge is a radar-type liquid level gauge.

[0012] As a further improvement of this utility model, the pulping tank includes a first pulping tank and a second pulping tank with the same structure, and the first pulping tank, the second pulping tank and the distribution tank are all equipped with a stirrer.

[0013] As a further improvement of this utility model, a first screw feeder is provided between the slaked lime silo and the first slurry tank, and a second screw feeder is provided between the slaked lime silo and the second slurry tank.

[0014] As a further improvement of this utility model, the first pulping tank is provided with a first liquid outlet pipe at the bottom, the first liquid outlet pipe is connected to the distribution tank, and a first vibrating screen is provided on the first liquid outlet pipe; the second pulping tank is provided with a second liquid outlet pipe at the bottom, the second liquid outlet pipe is connected to the distribution tank, and a second vibrating screen is provided on the second liquid outlet pipe.

[0015] As a further improvement of this utility model, the main water supply pipe includes a first water supply branch pipe and a second water supply branch pipe; the first water supply branch pipe includes a first branch pipe, a second branch pipe and a third branch pipe, the first branch pipe is connected to the first water inlet of the first pulping tank, the second branch pipe is connected to the air outlet pipe of the first spray blower, and the air outlet pipe of the first spray blower is connected to the second water inlet of the first pulping tank, and the third branch pipe is connected to the first liquid outlet pipe for cleaning the first vibrating screen; the second water supply branch pipe includes a fourth branch pipe, a fifth branch pipe and a sixth branch pipe, the fourth branch pipe is connected to the first water inlet of the second pulping tank, the fifth branch pipe is connected to the air outlet pipe of the second spray blower, and the air outlet pipe of the second spray blower is connected to the second water inlet of the second pulping tank, and the sixth branch pipe is connected to the second liquid outlet pipe for cleaning the second vibrating screen.

[0016] As a further improvement of this utility model, the first pulping tank is provided with a first overflow pipe at the top, and the first overflow pipe is connected to the distribution tank; the second pulping tank is provided with a second overflow pipe at the top, and the second overflow pipe is connected to the distribution tank.

[0017] As a further improvement of this utility model, the top of the distribution tank is provided with an air vent valve.

[0018] As a further improvement of this utility model, the lower part of the distribution tank is provided with a first discharge branch, a second discharge branch and a third discharge branch, which are respectively connected to the deacidification reaction towers of three waste incinerators.

[0019] Compared with the prior art, the advantages of this utility model are:

[0020] This utility model discloses a lime slurry preparation system suitable for waste-to-energy plants. It utilizes a sedimentation tank to collect lime slurry waste generated from ground washing, vibrating screen overflow, maintenance work, etc. A booster pump is installed within the sedimentation tank, with inlet and outlet filters respectively installed on the pump's inlet and outlet pipes to filter and remove impurities from the lime slurry waste. The booster pump's outlet pipe is connected to the feed end of the slurry preparation tank via a slurry recycling pipe, enabling the lime slurry waste collected in the sedimentation tank to be recycled back into the slurry preparation tank via the booster pump. This achieves low-cost recycling of lime slurry waste without affecting normal slurry preparation or the normal production of the waste incinerator, ensuring safety, stability, and high reliability. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structural principle of the lime slurry preparation system in a specific embodiment of this utility model;

[0022] Figure 2 This is a schematic diagram of the lime slurry preparation process in a specific embodiment of this utility model;

[0023] Legend: 1. Hydrated lime silo; 2. First slurry tank; 3. Second slurry tank; 4. Distribution tank; 5. Sedimentation tank; 6. Booster pump; 7. Inlet filter; 8. Outlet filter; 9. Level gauge; 10. High liquid level point; 11. Low liquid level point; 12. Control valve; 13. Slurry reuse pipe; 131. First reuse branch pipe; 132. Second reuse branch pipe; 14. First slide gate valve; 15. Second slide gate valve; 17. First screw feeder; 18. Second screw feeder; 19. First pneumatic slide gate; 20. Second pneumatic slide gate; 21. Main water supply pipe; 211. First water supply branch pipe; 212. Second water supply branch pipe. Branch pipe; 2111, First branch pipe; 2112, Second branch pipe; 2113, Third branch pipe; 2121, Fourth branch pipe; 2122, Fifth branch pipe; 2123, Sixth branch pipe; 22, First spray fan; 23, Second spray fan; 24, Agitator; 25, First outlet pipe; 26, Second outlet pipe; 27, First vibrating screen; 28, Second vibrating screen; 29, First overflow pipe; 30, Second overflow pipe; 31, Drain valve; 32, First discharge branch; 33, Second discharge branch; 34, Third discharge branch; 35, First conveying pump; 36, Second conveying pump; 37, Third conveying pump. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and specific preferred embodiments, but this does not limit the scope of protection of the present invention.

[0025] In the description of this utility model, it should be understood that the terms "side", "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.

[0027] Example

[0028] like Figure 1As shown, the lime slurry preparation system of this utility model, applicable to waste-to-energy plants, includes: a slaked lime silo 1, a slurry preparation tank, a distribution tank 4, a sedimentation tank 5, and a main water supply pipe 21. The feed end of the slurry preparation tank is connected to the slaked lime silo 1 and the main water supply pipe 21 via pipes, and the discharge end of the slurry preparation tank is connected to the distribution tank 4 via a pipe. The discharge end of the distribution tank 4 is connected to the deacidification reaction tower of the waste incinerator via a pipe. The sedimentation tank 5 is used to collect the lime slurry waste liquid generated by the lime slurry preparation system. The sedimentation tank 5 is equipped with a booster pump 6. The inlet pipe and outlet pipe of the booster pump 6 are respectively equipped with an inlet filter screen 7 and an outlet filter screen 8. The outlet pipe of the booster pump 6 is connected to the feed end of the slurry preparation tank via a slurry recycling pipe 13. The booster pump 6 is used to recycle the lime slurry waste liquid collected in the sedimentation tank 5 back to the slurry preparation tank. The inlet filter screen 7 and the outlet filter screen 8 filter and retain large lime slurry particles and undissolved lime particles to prevent damage to the quality of the lime slurry solution in the preparation tank and subsequent damage to downstream equipment.

[0029] In this embodiment, a sedimentation tank 5 is used to collect lime slurry waste liquid generated due to ground washing, vibrating screen overflow, maintenance work, etc. A booster pump 6 is installed in the sedimentation tank 5, and an inlet filter 7 and an outlet filter 8 are respectively installed on the inlet and outlet pipes of the booster pump 6 to achieve filtration and impurity removal of the lime slurry waste liquid. The outlet pipe of the booster pump 6 is connected to the feed end of the pulping tank through the slurry recycling pipe 13, which realizes the recycling of lime slurry waste liquid collected in the sedimentation tank 5 back to the pulping tank through the booster pump 6. This achieves the purpose of low-cost recycling of lime slurry waste liquid, and does not affect normal pulping and normal production of the waste incinerator. It is safe, stable and highly reliable.

[0030] like Figure 1 As shown, a level gauge 9 is installed inside the sedimentation tank 5, and high liquid level points 10 and low liquid level points 11 are respectively located on the side walls of the sedimentation tank 5. A booster pump 6 is linked to the level gauge 9. When the level gauge 9 detects that the lime slurry waste liquid in the sedimentation tank 5 is at the high liquid level point 10, the booster pump 6 starts, transporting the lime slurry waste liquid to the slurry preparation tank. When the level gauge 9 detects that the lime slurry waste liquid in the sedimentation tank 5 is at the low liquid level point 11, the booster pump 6 stops operating.

[0031] Furthermore, the level gauge 9 adopts a radar-type level gauge.

[0032] like Figure 1 As shown, the slurry preparation tank includes a first slurry preparation tank 2 and a second slurry preparation tank 3 with identical structures. The first slurry preparation tank 2, the second slurry preparation tank 3 and the distribution tank 4 are all equipped with a stirrer 24, which agitates the lime slurry in the tank to improve the uniformity of the lime slurry and prevent the lime slurry from settling.

[0033] like Figure 1As shown, the discharge port at the bottom of the hydrated lime silo 1 is connected to the feed end of the first screw feeder 17 via a pipe equipped with a first slide valve 14. The discharge end of the first screw feeder 17 is connected to the feed port of the first slurry tank 2 via a pipe equipped with a first pneumatic slide 19, thereby conveying the hydrated lime in the hydrated lime silo 1 to the first slurry tank 2. The discharge port at the bottom of the hydrated lime silo 1 is connected to the feed end of the second screw feeder 18 via a pipe equipped with a second slide valve 15. The discharge end of the second screw feeder 18 is connected to the feed port of the second slurry tank 3 via a pipe equipped with a second pneumatic slide 20, thereby conveying the hydrated lime in the hydrated lime silo 1 to the second slurry tank 3.

[0034] like Figure 1 As shown, the lower part of the first pulping tank 2 is provided with a first outlet pipe 25 with a control valve. The first outlet pipe 25 is connected to the distribution tank 4, and a first vibrating screen 27 is provided on the first outlet pipe 25 to ensure that the lime slurry in the first pulping tank 2 is filtered and screened before entering the distribution tank 4. The lower part of the second pulping tank 3 is provided with a second outlet pipe 26 with a control valve. The second outlet pipe 26 is connected to the distribution tank 4, and a second vibrating screen 28 is provided on the second outlet pipe 26 to ensure that the lime slurry in the second pulping tank 3 is filtered and screened before entering the distribution tank 4.

[0035] like Figure 1 As shown, the main water supply pipe 21 includes a first water supply branch pipe 211 and a second water supply branch pipe 212. The first water supply branch pipe 211 includes a first branch pipe 2111, a second branch pipe 2112, and a third branch pipe 2113, each equipped with a control valve. The first branch pipe 2111 is connected to the first inlet of the first pulping tank 2 to deliver industrial water into the first pulping tank 2. The second branch pipe 2112 is connected to the outlet pipe of the first spray fan 22, and the outlet pipe of the first spray fan 22 is connected to the second inlet of the first pulping tank 2 to spray industrial water onto the top of the first pulping tank 2 to cool the tank and reduce dust and mist inside. The third branch pipe 2113 is connected to the first outlet pipe 25 to deliver industrial water for cleaning the first vibrating screen 27. The second water supply branch pipe 212 includes a fourth branch pipe 2121, a fifth branch pipe 2122, and a sixth branch pipe 2123, each equipped with a control valve. The fourth branch pipe 2121 is connected to the first inlet of the second pulping tank 3 to deliver industrial water into the second pulping tank 3. The fifth branch pipe 2122 is connected to the outlet pipe of the second spray fan 23, and the outlet pipe of the second spray fan 23 is connected to the second inlet of the second pulping tank 3 to spray industrial water onto the top of the second pulping tank 3 to cool the tank and reduce dust and mist inside. The sixth branch pipe 2123 is connected to the second liquid outlet pipe 26 to transport industrial water for cleaning the second vibrating screen 28.

[0036] like Figure 1As shown, the first pulping tank 2 is equipped with a first overflow pipe 29 at its upper part, which is connected to the distribution tank 4. When the lime slurry in the first pulping tank 2 exceeds a preset height, the lime slurry flows into the distribution tank 4 through the first overflow pipe 29. The second pulping tank 3 is equipped with a second overflow pipe 30 at its upper part, which is connected to the distribution tank 4. When the lime slurry in the second pulping tank 3 exceeds a preset height, the lime slurry flows into the distribution tank 4 through the second overflow pipe 30.

[0037] like Figure 1 As shown, the top of the distribution tank 4 is equipped with an vent valve 31. During the lime slurry preparation process, the reaction between lime and water releases heat and produces gas (such as carbon dioxide), causing the pressure inside the tank to rise. The vent valve 31 can release the excess pressure inside the tank, preventing the tank from deforming or being damaged due to excessive pressure, and ensuring the safe operation of the equipment.

[0038] like Figure 1 As shown, the lower part of the distribution tank 4 is equipped with a first discharge branch 32, a second discharge branch 33, and a third discharge branch 34, which are respectively connected to the deacidification reaction towers of the three waste incinerators. Further, a first conveying pump 35 is installed on the first discharge branch 32. The first discharge branch 32 includes two branches, one of which connects to the deacidification reaction tower of waste incinerator #1, and the other branch returns to the distribution tank 4, enabling the lime slurry to circulate inside and outside the distribution tank 4 and preventing sedimentation. A second conveying pump 36 is installed on the second discharge branch 33. The second discharge branch 33 includes two branches, one of which connects to the deacidification reaction tower of waste incinerator #2, and the other branch returns to the distribution tank 4, enabling the lime slurry to circulate inside and outside the distribution tank 4 and preventing sedimentation. The third discharge branch 34 is equipped with a third conveying pump 37. The third discharge branch 34 includes two branches, one of which is connected to the deacidification reaction tower of the No. 3 waste incinerator, and the other branch returns to the distribution tank 4. This allows the lime slurry to circulate inside and outside the distribution tank 4, preventing the lime slurry from settling.

[0039] like Figure 2 As shown, during the preparation of lime slurry, the level of the lime slurry in the sedimentation tank 5 is monitored to determine whether the waste lime slurry should be recycled to the preparation tank. If the waste lime slurry in the sedimentation tank 5 needs to be added to the preparation tank, the booster pump 6 is activated to quantitatively deliver the waste lime slurry into the preparation tank. If the waste lime slurry in the sedimentation tank 5 does not need to be added to the preparation tank, industrial water is directly added to the preparation tank. It can be understood that in other embodiments, the waste lime slurry in the sedimentation tank 5 can also be recycled to the distribution tank 4.

[0040] In this embodiment, in order to solve the problem that the signal is not sent in time due to the failure of the low liquid level 11 in the sedimentation tank 5 or other reasons, which affects the normal pulping process, the control system will send a control signal again after the lift pump 6 is started for 15 minutes and no low liquid level signal is detected, so that the normal pulping process can be carried out in time.

[0041] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. A lime slurry preparation system suitable for use in a waste-to-energy plant, characterized in that, The application relates to a lime slurry preparation system for a waste incinerator. The lime slurry preparation system comprises a lime bin (1), a pulp preparation tank, a distribution tank (4), a sedimentation tank (5) and a water supply main (21), the pulp preparation tank is connected with the lime bin (1) and the water supply main (21) through pipelines at the feeding end respectively, the pulp preparation tank is connected with the distribution tank (4) through a pipeline at the discharging end, the discharging end of the distribution tank (4) is connected with a deacidification reaction tower of the waste incinerator through a pipeline, the sedimentation tank (5) is used for collecting lime slurry waste liquid generated by the lime slurry preparation system, a lifting pump (6) is arranged in the sedimentation tank (5), an inlet filter screen (7) and an outlet filter screen (8) are arranged on the inlet pipeline and the outlet pipeline of the lifting pump (6) respectively, and the outlet pipeline of the lifting pump (6) is connected with the feeding end of the pulp preparation tank through a slurry recycling pipeline (13), and the lifting pump (6) is used for recycling the lime slurry waste liquid collected in the sedimentation tank (5) to the pulp preparation tank.

2. The lime slurry preparation system suitable for use in a waste incineration plant according to claim 1, characterized in that, A liquid level meter (9) is arranged in the sedimentation tank (5), and a high liquid level point (10) and a low liquid level point (11) are arranged on the side wall of the sedimentation tank (5); the lifting pump (6) is connected with the liquid level meter (9), when the liquid level meter (9) detects that the lime slurry waste liquid in the sedimentation tank (5) is at the high liquid level point (10), the lifting pump (6) is started, and when the liquid level meter (9) detects that the lime slurry waste liquid in the sedimentation tank (5) is at the low liquid level point (11), the lifting pump (6) stops running.

3. The lime slurry preparation system suitable for use in a waste incineration plant according to claim 2, characterized in that, The liquid level meter (9) is a radar type liquid level meter.

4. The lime slurry preparation system suitable for waste incineration plants according to any one of claims 1 to 3, characterized in that, The pulp preparation tank comprises a first pulp preparation tank (2) and a second pulp preparation tank (3) which are identical in structure, and a stirrer (24) is arranged in each of the first pulp preparation tank (2), the second pulp preparation tank (3) and the distribution tank (4).

5. The lime slurry preparation system suitable for use in a waste incineration plant according to claim 4, characterized in that, A first screw feeder (17) is arranged between the lime bin (1) and the first pulp preparation tank (2), and a second screw feeder (18) is arranged between the lime bin (1) and the second pulp preparation tank (3).

6. The lime slurry preparation system suitable for use in a waste incineration plant according to claim 4, characterized in that, A first liquid outlet pipe (25) is arranged at the lower part of the first pulp preparation tank (2), the first liquid outlet pipe (25) is connected with the distribution tank (4), and a first vibrating screen (27) is arranged on the first liquid outlet pipe (25); a second liquid outlet pipe (26) is arranged at the lower part of the second pulp preparation tank (3), the second liquid outlet pipe (26) is connected with the distribution tank (4), and a second vibrating screen (28) is arranged on the second liquid outlet pipe (26).

7. The lime slurry preparation system suitable for use in a waste incineration plant according to claim 6, characterized in that, The water supply main pipe (21) comprises a first water supply branch pipe (211) and a second water supply branch pipe (212); the first water supply branch pipe (211) comprises a first branch pipe (2111), a second branch pipe (2112) and a third branch pipe (2113), the first branch pipe (2111) is connected with a first water inlet of the first pulping tank (2), the second branch pipe (2112) is connected with an air outlet pipe of the first spray fan (22), and the air outlet pipe of the first spray fan (22) is connected to a second water inlet of the first pulping tank (2), and the third branch pipe (2113) is connected with the first liquid outlet pipe (25) for cleaning the first vibrating screen (27); the second water supply branch pipe (212) comprises a fourth branch pipe (2121), a fifth branch pipe (2122) and a sixth branch pipe (2123), the fourth branch pipe (2121) is connected with a first water inlet of the second pulping tank (3), the fifth branch pipe (2122) is connected with an air outlet pipe of the second spray fan (23), and the air outlet pipe of the second spray fan (23) is connected to a second water inlet of the second pulping tank (3), and the sixth branch pipe (2123) is connected with the second liquid outlet pipe (26) for cleaning the second vibrating screen (28).

8. The lime slurry preparation system suitable for use in a waste incineration plant according to claim 4, characterized in that, The first pulping tank (2) is provided with a first overflow pipe (29) at the upper portion, and the first overflow pipe (29) is connected with the distribution tank (4); the second pulping tank (3) is provided with a second overflow pipe (30) at the upper portion, and the second overflow pipe (30) is connected with the distribution tank (4).

9. A lime slurry preparation system for use in a waste-to-energy plant according to any one of claims 5 to 8, characterized in that, The distribution tank (4) is provided with an emptying valve (31) at the top.

10. A lime slurry preparation system suitable for use in a waste-to-energy plant according to any one of claims 5 to 8, characterized in that, The distribution tank (4) is provided with a first discharge branch (32), a second discharge branch (33) and a third discharge branch (34) at the lower portion, respectively, so as to be connected to three waste incinerators.

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