Gypsum crystallization and precipitation device

Abstract

The utility model discloses a gypsum crystallization precipitation device which comprises a fixed shell, the bottom end of the fixed shell is connected with a connecting cylinder, the whole fixed shell is of a cylindrical structure, the top of the fixed shell is fixedly connected with a mounting cover, a central pipeline is mounted in the fixed shell, and the top end of the central pipeline penetrates through the mounting cover; a central pipe mixing area is formed in the inner area of the central pipeline, an outer ring reaction settling area is formed in the area, located outside the central pipeline, in the fixed shell, and a bottom sludge area is formed in the conical barrel at the bottom end of the fixed shell. A large amount of gypsum crystallization sludge is prevented from adhering to the surface of mechanical stirring equipment to form large blocks to block a central pipe and affect normal operation of the device, the bottom sludge area is provided with a pneumatic butterfly valve and an automatic / manual control system of the pneumatic butterfly valve, regular sludge regulation is simple, convenient and flexible, and the whole device is simple, reliable and practical.

Description

Technical Field

[0001] The utility model relates to the field of garbage leachate treatment, in particular to a gypsum crystallization precipitation device. Background Art

[0002] At present, MBR+NF has become the mainstream process for leachate treatment, but this combined process inevitably produces nanofiltration concentrate that accounts for 15-20% of the original liquid volume. The material membrane separation technology can achieve the reduction of nanofiltration concentrate, but in the separation and concentration process, the concentration of divalent ions such as calcium and sulfate in the feed liquid carried in the nanofiltration concentrate is getting higher and higher, causing the concentration polarization pollution to become more and more serious. Even when the supersaturation is too large, the scale inhibitor cannot prevent the precipitation of calcium sulfate and cause serious scaling, shortening the membrane life or damaging the membrane components. This is also the fundamental reason why the single material membrane separation technology can only achieve the reduction of nanofiltration concentrate. Therefore, in order to achieve the full treatment of nanofiltration concentrate, it is necessary to assist in the effective removal of calcium and sulfate ion treatment units in the membrane process system, so as to avoid excessive accumulation of calcium and sulfate ions in the system to ensure the normal operation of the membrane system.

[0003] Obviously, using the direct formation of gypsum precipitation between calcium and sulfate ions in wastewater is one of the best technical approaches to remove calcium and sulfate ions. However, gypsum precipitation is easily affected by humic acid and impurity ions in nanofiltration concentrate. Under the natural neutral conditions of nanofiltration concentrate, it is difficult to produce gypsum precipitation. Studies have found that under acidic conditions, the inhibitory effects of humic acid and impurity ions can be overcome, and high concentrations of calcium and sulfate ions can spontaneously crystallize and precipitate, thereby effectively reducing the concentrations of the two in the liquid phase, and it is expected to achieve closed-loop treatment of nanofiltration concentrate. For this reason, we propose a gypsum crystallization precipitation device. Utility Model Content

[0004] The purpose of the utility model is to provide a gypsum crystallization precipitation device to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a gypsum crystallization precipitation device, comprising a fixed shell, the bottom end of the fixed shell is connected to a connecting cylinder, the fixed shell is an overall cylindrical structure, the top of the fixed shell is fixedly connected to a mounting cover, a central pipe is installed inside the fixed shell, and the top of the central pipe passes through the mounting cover, the internal area of ​​the central pipe forms a central pipe mixing zone, the area of ​​the fixed shell outside the central pipe forms an outer ring reaction precipitation zone, the inside of the conical cylinder at the bottom end of the fixed shell forms a bottom sludge zone, and the top of the central pipe is respectively connected to a hydrochloric acid pipe and a water inlet pipe.

[0006] Preferably, an online immersion pH meter and a water outlet weir are provided in the outer ring reaction precipitation zone.

[0007] Preferably, the bottom sludge zone is a conical bucket structure, and the outer side inclination angle of the bottom sludge zone is greater than sixty degrees.

[0008] Preferably, a mud discharge pipe is installed at the bottom end of the bottom mud area, and the end of the mud discharge pipe passes through the connecting tube, and a pneumatic butterfly valve on the mud discharge pipe of the mud area is installed on the outside of one end of the mud discharge pipe located outside the connecting tube.

[0009] Preferably, a water inlet pipe ball valve is installed on the outside of the water inlet pipe.

[0010] Preferably, the bottom of the fixed shell is located outside the connecting tube and is equidistantly and fixedly connected with four supporting legs.

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

[0012] 1. In the utility model, the wastewater in the central pipe and the hydrochloric acid are mixed by hydraulic stirring to adjust the pH value, so as to prevent the gypsum crystal sludge from adhering to the surface of the mechanical stirring equipment in large quantities to form large blocks and block the central pipe, thus affecting the normal operation of the device.

[0013] 2. The outer ring reaction precipitation zone of the utility model is provided with an immersed online pH meter near the bottom of the central tube, which can achieve the effect of controlling the appropriate pH value range of the crystallization reaction.

[0014] 3. The bottom sludge area of ​​the utility model is provided with a pneumatic butterfly valve and its automatic / manual control system, which makes regular sludge removal simple and flexible, and the whole device is simple, reliable and practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0016] In the figure: 1. Ball valve on water inlet pipe; 2. Hydrochloric acid pipe; 3. Central pipe mixing area; 4. Outer ring reaction sedimentation area; 5. Bottom sludge area; 6. Online immersion pH meter; 7. Outlet weir; 8. Pneumatic butterfly valve on sludge discharge pipe in sludge area; 9. Water inlet pipe; 10. Sludge discharge pipe; 11. Fixed shell; 12. Central pipe; 13. Support legs; 14. Installation cover. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0018] See also Figure 1 The utility model provides a technical solution: a gypsum crystallization precipitation device, including a fixed shell 11, the bottom end of the fixed shell 11 is connected to a connecting tube, the fixed shell 11 is an overall cylindrical structure, and the top of the fixed shell 11 is fixedly connected to a mounting cover 14.

[0019] It should be noted that the fixing shell 11 is cylindrical, and a mounting cover 14 is mounted on the top thereof to prevent foreign matter from entering the fixing shell 11 .

[0020] A central pipe 12 is installed inside the fixed shell 11, and the top of the central pipe 12 passes through the installation cover 14. The internal area of ​​the central pipe 12 forms a central pipe mixing zone 3, the area outside the central pipe 12 in the fixed shell 11 forms an outer ring reaction sedimentation zone 4, and the inside of the conical cylinder at the bottom of the fixed shell 11 forms a bottom sludge zone 5. The top of the central pipe 12 is respectively connected to the hydrochloric acid pipe 2 and the water inlet pipe 9.

[0021] It should be noted that the hydraulic retention time of the outer ring reaction sedimentation zone 4 is not less than 3 hours, and the pH value is controlled between 2.3 and 3.5. By controlling the appropriate opening and closing degree of the ball valve 1 on the water inlet pipe, a certain flow of process wastewater containing high concentrations of calcium and sulfate ions flows into the upper part of the central tube. Concentrated hydrochloric acid is controlled by the online immersion pH meter 6 to start the metering pump and is also added from the upper part of the central pipeline 12 through the hydrochloric acid tube 2. The pH is adjusted by hydraulic stirring in the mixing zone 3 of the central tube, and then flows out from the bottom of the mixing zone 3 of the central tube into the outer ring reaction sedimentation zone 4. After staying for more than 3 hours, a crystallization reaction is carried out, and the formed precipitate settles to the wall of the lower conical bucket under the action of gravity, while the supernatant in the reaction sedimentation zone flows into the outlet weir 7 for discharge, and the sludge on the wall of the conical bucket further slides down to the bottom sludge zone 5, and then the pneumatic butterfly valve 8 is opened and closed regularly for further discharge.

[0022] An online immersion pH meter 6 and a water outlet weir 7 are arranged in the outer ring reaction precipitation zone 4 .

[0023] It should be noted that the hydraulic retention time of the outer ring reaction precipitation zone is not less than 3 hours, the pH value is controlled between 2.3-3.5, and concentrated hydrochloric acid is added from the upper part of the central pipeline 12 through the hydrochloric acid pipe 2 by controlling the online immersion pH meter 6 to start the metering pump. The pH is adjusted by hydraulic stirring in the mixing zone 3 of the central pipe, and the pH value is controlled between 2.3-3.5.

[0024] The bottom sludge area 5 is a conical bucket structure, and the outer side inclination angle of the bottom sludge area 5 is greater than sixty degrees.

[0025] It should be noted that the outer inclination angle of the bottom sludge area 5 is set to be greater than sixty degrees. A larger outer wall inclination angle helps to reduce the adhesion of sludge on the bucket wall, which can reduce the flow resistance of the material in the bucket and help improve the fluidity of the material.

[0026] A mud discharge pipe 10 is installed at the bottom end of the bottom mud area 5, and the end of the mud discharge pipe 10 passes through the connecting tube. A pneumatic butterfly valve 8 on the mud area mud discharge pipe is installed on the outside of one end of the mud discharge pipe 10 located outside the connecting tube.

[0027] It should be noted that the sludge in the bottom sludge area 5 can be easily discharged through the sludge discharge pipe 10 , and the pneumatic butterfly valve 8 on the sludge discharge pipe of the sludge area on the sludge discharge pipe 10 can control the on-off of the sludge discharge pipe 10 .

[0028] The outer side of the water inlet pipe 9 is provided with a water inlet pipe upper ball valve 1 .

[0029] It should be noted that the on-off of the water inlet pipe 9 can be controlled by the ball valve 1 on the water inlet pipe.

[0030] The bottom of the fixed shell 11 is located outside the connecting tube and is fixedly connected with four supporting legs 13 at equal intervals.

[0031] It should be noted that four supporting legs 13 are installed at the four corners of the bottom of the fixed shell 11 to provide a stable support for the sedimentation device.

[0032] The working process of this utility model:

[0033] Step 1: The ball valve 1 on the water inlet pipe is opened, and the wastewater flows into the mixing zone 3 of the central pipe in a continuous manner;

[0034] Step 2: start the metering pump under the control of the online immersion pH meter 6 to add concentrated hydrochloric acid from the upper part of the central tube through the hydrochloric acid tube 2;

[0035] Step 3: The wastewater and concentrated hydrochloric acid are mixed by hydraulic stirring in the central tube mixing zone 3 to adjust the pH;

[0036] Step 4: The mixed wastewater with pH adjusted flows from the bottom of the central tube mixing zone 3 into the outer ring reaction precipitation zone 4;

[0037] Step 5: the wastewater in the outer ring reaction precipitation zone 4 crystallizes and precipitates during the upward flow process;

[0038] Step 6: the crystallization reaction precipitate in the outer ring reaction precipitation zone 4 settles on the conical bucket wall;

[0039] Step 7: The crystallization reaction precipitation supernatant in the outer ring reaction precipitation zone 4 flows into the outlet weir 7 for discharge;

[0040] Step 8: The sediment settled on the wall of the conical bucket slides down to the bottom sludge area 5;

[0041] Step 9: Start the pneumatic butterfly valve 8 regularly to drain mud.

[0042] In the description of the present invention, it should be understood that the terms "coaxial", "bottom", "one end", "top", "middle", "the other end", "upper", "one side", "top", "inside", "front", "center", "both ends" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0043] In addition, the terms "first", "second", "third" and "fourth" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first", "second", "third" and "fourth" may explicitly or implicitly include at least one of such features.

[0044] In the present utility model, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the utility model according to the specific circumstances.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A gypsum crystallization precipitation device, comprising a fixed shell (11), the bottom end of the fixed shell (11) is connected to a connecting tube, characterized in that: The fixed shell (11) is in the form of a cylindrical structure as a whole. A mounting cover (14) is fixedly connected to the top of the fixed shell (11). A central pipe (12) is mounted inside the fixed shell (11), and the top of the central pipe (12) passes through the mounting cover (14). The inner area of ​​the central pipe (12) forms a central pipe mixing area (3). The area outside the central pipe (12) in the fixed shell (11) forms an outer ring reaction sedimentation area (4). The inner part of the conical cylinder at the bottom of the fixed shell (11) forms a bottom sludge area (5). The top of the central pipe (12) is respectively connected to a hydrochloric acid pipe (2) and a water inlet pipe (9).

2. A gypsum crystallization precipitation device according to claim 1, characterized in that: An online immersion pH meter (6) and a water outlet weir (7) are arranged in the outer ring reaction precipitation zone (4).

3. A gypsum crystallization precipitation device according to claim 1, characterized in that: The bottom sludge area (5) is a conical bucket structure, and the outer side inclination angle of the bottom sludge area (5) is greater than sixty degrees.

4. A gypsum crystallization precipitation device according to claim 1, characterized in that: A mud discharge pipe (10) is installed at the bottom end of the bottom mud area (5), and the end of the mud discharge pipe (10) passes through the connecting tube. A pneumatic butterfly valve (8) on the mud area mud discharge pipe is installed on the outside of one end of the mud discharge pipe (10) located outside the connecting tube.

5. A gypsum crystallization precipitation device according to claim 1, characterized in that: A water inlet pipe upper ball valve (1) is installed on the outer side of the water inlet pipe (9).

6. A gypsum crystallization precipitation device according to claim 1, characterized in that: The bottom of the fixed shell (11) is located outside the connecting tube and is fixedly connected to four supporting legs (13) at equal distances.

Images