Low-sodium-sulfate naphthalene water reducer and preparation method thereof

Abstract

The invention discloses a low-sodium-sulfate naphthalene water reducer and a preparation method thereof, and relates to the field of preparation of naphthalene water reducers, the low-sodium-sulfate naphthalene water reducer is prepared by using special equipment, and the preparation conditions are as follows: the temperature is-10 DEG C or below; the pressure intensity is 2 to 4 Mpa; the content of sodium sulfate in the naphthalene water reducer with low sodium sulfate is 0.05-10% wt. According to the preparation method of the low-sodium-sulfate-content naphthalene water reducer and the special equipment thereof, the crystallization temperature, efficiency, pressure, separation and collection of the low-sodium-sulfate-content naphthalene water reducer can be comprehensively regulated and controlled, so that sodium sulfate crystals are rapidly separated out, and the low-sodium-sulfate-content naphthalene water reducer is rapidly, stably and conveniently obtained.

Description

Technical Field

[0001] The present invention relates to the field of preparation of naphthalene-based water reducers, and particularly relates to a low-sodium-sulfate naphthalene-based water reducer and a preparation method thereof. Background Art

[0002] For the preparation of low-sodium-sulfate naphthalene-based water reducers, a dispersant is generally added and refrigerated to precipitate a part of sodium sulfate. The unprecipitated liquid is taken for drying to obtain a low-sodium-sulfate water reducer, increasing the content of the water reducer so that the performance of the water reducer can be doubled.

[0003] However, in the prior art, the water reducer is generally introduced into a reaction kettle, and a spiral refrigerant is provided in the reaction kettle to refrigerate the water reducer. However, it generally takes 40 to 60 minutes to reduce the temperature of the water reducer to -10°C or below at one time, with low efficiency.

[0004] Therefore, it is very necessary to propose a low-sodium-sulfate naphthalene-based water reducer and a preparation method thereof to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a low-sodium-sulfate naphthalene-based water reducer and a preparation method thereof to solve the problems raised in the above background art.

[0006] To achieve the above purpose, the present invention provides the following technical solution: A preparation method of a low-sodium-sulfate naphthalene-based water reducer for preparing a low-sodium-sulfate naphthalene-based water reducer, using a special device to prepare the low-sodium-sulfate naphthalene-based water reducer, and the preparation conditions are: a temperature of -10°C and below; a pressure of 2 to 4 Mpa; the sodium sulfate content in the concentration of the low-sodium-sulfate naphthalene-based water reducer is between 0.05 and 10% wt; The special device includes a reaction kettle, and a naphthalene-based water reducer inlet pipe for introducing the naphthalene-based water reducer is arranged in the reaction kettle. A refrigerant is stored in the reaction kettle, and the refrigerant completely immerses the naphthalene-based water reducer inlet pipe; When the naphthalene-based water reducer flows in the naphthalene-based water reducer inlet pipe, it is refrigerated by the refrigerant.

[0007] Preferably, three naphthalene-based water reducer inlet pipes are provided, and the naphthalene-based water reducer inlet pipes are arranged in a zigzag manner.

[0008] Preferably, the special device further includes a raw material tank for storing a naphthalene-based water reducer liquid for normal-temperature construction, and the initial concentration of sodium sulfate in the naphthalene-based water reducer liquid for normal-temperature construction is 7-20% wt; A pump body for transporting the naphthalene-based water reducer liquid for normal-temperature construction into the naphthalene-based water reducer inlet pipe is arranged on the raw material tank.

[0009] Preferably, the special equipment further includes a first collection tank and a second collection tank. A first collection pipe or a second collection pipe, which are respectively connected to the first collection tank and the second collection tank, is arranged below the reaction kettle. Solenoid valves are arranged on both the first collection pipe and the second collection pipe.

[0010] Preferably, filter layers are arranged in both the first collection tank and the second collection tank. Above the filter layer is a crystal chamber, and below the filter layer is a liquid chamber.

[0011] Preferably, the special equipment further includes a finished product tank, which is communicated with the liquid chamber.

[0012] Preferably, concentration transmitters for detecting the sodium sulfate content in the naphthalene-based water reducer are arranged inside both the first collection tank and the second collection tank; A circulating pump body is connected to both the first collection tank and the second collection tank and is communicated with the liquid chamber. A switching valve is arranged at the communication position. A circulating pipeline for circulating and supplying the naphthalene-based water reducer to the naphthalene-based water reducer introduction pipe is also arranged on the circulating pump body.

[0013] Preferably, the refrigerant in the reaction kettle circulates for refrigeration.

[0014] Preferably, electronic control valves are arranged on all three naphthalene-based water reducer introduction pipes.

[0015] Preferably, a number of decompression mechanisms are arranged on the naphthalene-based water reducer introduction pipe. The decompression mechanism includes a flow blocking ring. A magnetic positioning block is fixedly arranged inside the flow blocking ring. An electromagnetic fixing block is fixedly arranged on the outer ring of the naphthalene-based water reducer introduction pipe. The magnetic positioning block and the electromagnetic fixing block are fixedly attracted to each other; First magnetic rings are fixedly arranged at both ends of the flow blocking ring. A second magnetic ring is arranged on the side of the first magnetic ring away from the flow blocking ring. The magnetic poles of the first magnetic ring and the second magnetic ring repel each other. The second magnetic ring is fixedly installed on the inner wall of the naphthalene-based water reducer introduction pipe. A gap is left between the second magnetic ring and the first magnetic ring.

[0016] The technical effects and advantages of the present invention: 1. Through the preparation method of the naphthalene-based water reducer with low sodium sulfate content and its special equipment, the present invention can comprehensively regulate the crystallization temperature, efficiency, pressure, separation and collection of the naphthalene-based water reducer with low sodium sulfate content, so that sodium sulfate crystals can precipitate quickly, and the naphthalene-based water reducer with low sodium sulfate content can be obtained quickly, stably and conveniently; 2. When the naphthalene-based water reducer passes through the naphthalene-based water reducer introduction pipe, it can be quickly refrigerated by the refrigerant in the reaction kettle, and the cooling efficiency is fast, which increases the preparation efficiency of the naphthalene-based water reducer with low sodium sulfate content; 3. In the present invention, the preparation efficiency of the low-sodium-sulfate naphthalene-based water reducer is improved; and it is easy to control the specific concentration of the low-sodium-sulfate naphthalene-based water reducer without adjusting the preparation time and equipment, saving the preparation cost; 4. The present invention provides a method for continuously collecting the naphthalene-based water reducer, enabling the special equipment to operate without shutdown and reducing the shutdown cost; 5. The present invention also achieves the purpose of separating the treated naphthalene-based water reducer and sodium sulfate crystals without shutdown; 6. In the present invention, there is no need for an additional pressure control mechanism to control the pressure of the naphthalene-based water reducer, such that the pressure of the naphthalene-based water reducer in the naphthalene-based water reducer inlet pipe is exactly controlled within appropriate conditions; and the pressure reducing mechanism can be used in combination with the special equipment to well control the pressure of the naphthalene-based water reducer in any one of the three naphthalene-based water reducer inlet pipes. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic structural diagram of a perspective view of the special equipment for preparing the low-sodium-sulfate naphthalene-based water reducer of the present invention.

[0018] Figure 2 It is a schematic structural diagram of another perspective view of the special equipment for preparing the low-sodium-sulfate naphthalene-based water reducer of the present invention.

[0019] Figure 3 It is a schematic three-dimensional internal structure diagram of the reaction kettle of the present invention.

[0020] Figure 4 It is a schematic plan view of the internal structure of the reaction kettle of the present invention.

[0021] Figure 5 For the present invention Figure 4 The enlarged schematic diagram of the structure at A.

[0022] Figure 6 It is a schematic structural diagram of the circulating pump body of the present invention.

[0023] In the figure: 1. Reaction kettle; 2. Refrigerant circulation inlet pipe; 3. Refrigerant circulation discharge pipe; 4. First collection tank; 5. Second collection tank; 6. Product tank; 7. Raw material tank; 8. Naphthalene-based water reducer feed pipe; 9. Pump body; 10. First collection pipe; 11. Second collection pipe; 12. Five-way adapter box; 13. Four-way adapter box; 14. Naphthalene-based water reducer inlet pipe; 15. Pressure sensor; 16. Solenoid valve; 17. Crystal chamber; 18. Filter layer; 19. Liquid chamber; 20. Flow resistance ring; 21. Electromagnetic fixing block; 22. Magnetic positioning block; 23. First magnetic ring; 24. Second magnetic ring; 25. On-off valve; 26. Circulating pump body; 27. Circulation pipeline. DETAILED DESCRIPTION OF THE INVENTION

[0024] Example 1: The present invention provides a preparation method of a naphthalene-based water reducer with low sodium sulfate content, which comprises the following steps: 1) Prepare a naphthalene-based water reducer liquid for normal-temperature construction, wherein the sodium sulfate content is above 7% wt, mostly 10 - 20% wt or higher; 2) Introduce the naphthalene-based water reducer liquid for normal-temperature construction into a special device for producing a naphthalene-based water reducer with low sodium sulfate content, and refrigerate the naphthalene-based water reducer liquid for normal-temperature construction; Specifically, it includes: 21) Reduce the sodium sulfate content in the naphthalene-based water reducer liquid for normal-temperature construction by the cooling method: intelligently control the temperature, pressure, concentration and stirring time of the naphthalene-based water reducer liquid during the whole reaction process, reduce the temperature of the naphthalene-based water reducer liquid to -10°C or below at one time, and prepare liquid naphthalene-based water reducers with different sodium sulfate contents by controlling the reaction time. Keep the naphthalene-based water reducer liquid at a temperature of -10°C or below, a pressure of 2 - 4 Mpa and under stirring conditions for 0.5 - 5 hours, so that the dissolved sodium sulfate rapidly crystallizes and precipitates. When the concentration detection device (concentration transmitter) of the special device detects that the sodium sulfate content in the naphthalene-based water reducer liquid is 0.05 - 5% wt, export the obtained naphthalene-based water reducer liquid, and export the precipitated sodium sulfate crystals separately to prepare a naphthalene-based water reducer with low sodium sulfate content. Reference Figure 3 As shown in , add the naphthalene-based water reducer into the reaction kettle 1 of the special device for producing a naphthalene-based water reducer with low sodium sulfate content through the naphthalene-based water reducer inlet pipe 14; introduce a refrigerant into the reaction kettle 1, and the refrigerant completely immerses the naphthalene-based water reducer inlet pipe 14. The naphthalene-based water reducer inlet pipe 14 is arranged in a zigzag manner, and when the naphthalene-based water reducer passes through the naphthalene-based water reducer inlet pipe 14, it can be rapidly refrigerated by the refrigerant in the reaction kettle 1, generally being able to be reduced to -10°C or below at one time within 1 - 5 minutes. The cooling efficiency is fast, which increases the preparation efficiency of the naphthalene-based water reducer with low sodium sulfate content.

[0025] See the appendix Figure 1 As shown in , a refrigerant circulation inlet pipe 2 and a refrigerant circulation outlet pipe 3 are arranged on the reaction kettle 1. Generally, a refrigerant cooling tower is arranged outside the reaction kettle 1. Use a refrigerant delivery pump to transport the refrigerant in the refrigerant cooling tower from the refrigerant circulation inlet pipe 2 to the reaction kettle 1. When the refrigerant absorbs heat from the naphthalene-based water reducer in the naphthalene-based water reducer inlet pipe 14, it is discharged from the refrigerant circulation outlet pipe 3 to the refrigerant cooling tower for circulation to achieve the effect of circulating refrigeration; this refrigeration method uses a large amount of refrigerant, and the refrigerant is completely sealed without loss, with low cost, and can rapidly refrigerate the naphthalene-based water reducer.

[0026] It should be noted that the refrigerant cooling tower is a common existing device for cooling the refrigerant, and it usually has a radiator and an evaporator inside, which will not be elaborated here.

[0027] In this embodiment, three naphthalene-based water reducer inlet pipes 14 are provided inside the reactor 1, and naphthalene-based water reducer can be introduced into all three naphthalene-based water reducer inlet pipes 14. The initial concentration of the naphthalene-based water reducer is: 20% wt. Only introducing the naphthalene-based water reducer into one naphthalene-based water reducer inlet pipe 14 can cause most of the coolant in the reactor 1 to be used to absorb the heat in the naphthalene-based water reducer. Therefore, the temperature of the naphthalene-based water reducer can reach about -20°C after being refrigerated; more sodium sulfate crystals are precipitated, and finally a naphthalene-based water reducer with sodium sulfate of 0.05 - 5% wt can be formed.

[0028] Example 2: Introducing the naphthalene-based water reducer into two naphthalene-based water reducer inlet pipes 14 simultaneously can cause most of the coolant in the reactor 1 to be used to absorb the heat of the naphthalene-based water reducer in the two naphthalene-based water reducer inlet pipes 14. Therefore, the temperature of the naphthalene-based water reducer can reach about -15°C after being refrigerated; more sodium sulfate crystals are precipitated, and finally a naphthalene-based water reducer with sodium sulfate of 1 - 6% wt can be formed.

[0029] Example 3: Introducing the naphthalene-based water reducer into three naphthalene-based water reducer inlet pipes 14 simultaneously can cause the coolant in the reactor 1 to be used to absorb the heat in the naphthalene-based water reducer at the same time, and the heat absorption capacity decreases relatively. Therefore, the temperature of the naphthalene-based water reducer can reach about -10°C after being refrigerated; more sodium sulfate crystals are precipitated, and finally a naphthalene-based water reducer with sodium sulfate of 1.05 - 10% wt can be formed.

[0030] In summary, Examples 1 to 3 disclose a method and equipment for preparing naphthalene-based water reducers with different sodium sulfate concentrations; it replaces the method of refrigerating and preparing naphthalene-based water reducers using refrigerant tubes in the comparative document (patent name: A preparation method and its special equipment for naphthalene-based water reducers with low sodium sulfate content, patent application number: 201310025329.9), improves the preparation efficiency of low-sodium sulfate naphthalene-based water reducers; and is easy to control the specific concentration of low-sodium sulfate naphthalene-based water reducers, without adjusting the preparation time and equipment, saving the preparation cost.

[0031] Example 4: Refer to Figure 1 and Figure 2 As shown in

[0032] Refer toFigure 3 and Figure 4 As shown in Figure 4 , a four-way adapter box 13 and a five-way adapter box 12 are respectively arranged inside the upper part and the lower part above the reaction kettle 1. The four-way adapter box 13 is connected between three naphthalene-based water reducer inlet pipes 14 and the naphthalene-based water reducer feed pipe 8; an electronic control valve for controlling its on-off is arranged at the connection between the four-way adapter box 13 and the three naphthalene-based water reducer inlet pipes 14; the five-way adapter box 12 is connected between the three naphthalene-based water reducer inlet pipes 14, the first collection pipe 10 and the second collection pipe 11; solenoid valves 16 are arranged on both the first collection pipe 10 and the second collection pipe 11; when the naphthalene-based water reducer enters the reaction kettle 1 through the naphthalene-based water reducer feed pipe 8, it first enters the four-way adapter box 13, and the naphthalene-based water reducer is branched into the three naphthalene-based water reducer inlet pipes 14 by the four-way adapter box 13. When the naphthalene-based water reducer passes through the naphthalene-based water reducer inlet pipes 14, it is cooled by the refrigerant in the reaction kettle 1 and then enters the five-way adapter box 12, and the cooled naphthalene-based water reducer enters the first collection tank 4 or the second collection tank 5.

[0033] Furthermore, by controlling the solenoid valve 16 on the first collection pipe 10 or the second collection pipe 11 to open, the naphthalene-based water reducer can enter the first collection tank 4 or the second collection tank 5 respectively. When one of the first collection tank 4 or the second collection tank 5 is full, the corresponding solenoid valve 16 of the other can be opened to make the naphthalene-based water reducer enter the other empty tank body, which is convenient for having sufficient time to replace the new collection tanks (including the first collection tank 4 and the second collection tank 5).

[0034] In summary, the present invention provides a method for continuously collecting naphthalene-based water reducer, enabling the special equipment to operate without shutdown and reducing the shutdown cost.

[0035] Among them, a filter layer 18 is further arranged inside the lower end of the first collection tank 4 or the second collection tank 5. The filter layer 18 can be used to separate the naphthalene-based water reducer. Below the filter layer 18 is a liquid chamber 19, and above the filter layer 18 is a crystal chamber 17. The naphthalene-based water reducer enters the liquid chamber 19 through the filter layer 18, while the sodium sulfate crystals are blocked by the filter layer 18 and stay in the crystal chamber 17; therefore, the present invention also realizes the purpose of separating the treated naphthalene-based water reducer and sodium sulfate crystals without shutdown.

[0036] Refer to Figures 1 to 4 As shown in Figures 1 to 4 , the special equipment further includes a raw material tank 7 and a finished product tank 6; Among them, the raw material tank 7 is used to store the naphthalene-based water reducer liquid for normal temperature construction, and the initial concentration of sodium sulfate in the naphthalene-based water reducer liquid for normal temperature construction is 7-20% wt or higher; a pump body 9 for pumping the naphthalene-based water reducer is installed on the raw material tank 7, and the pump body 9 is connected to the finished product tank 6. When the pump body 9 is started, the naphthalene-based water reducer can be pumped into the finished product tank 6; Among them, the finished product tank 6 is used to store naphthalene-based water reducing agent with low sodium sulfate content. After being refrigerated and the sodium sulfate crystals are precipitated, the naphthalene-based water reducing agent with low sodium sulfate content can be sent to the finished product tank 6 for storage and directly transported and used without secondary packaging. The power of a pump body 9 is fully utilized to complete the preparation, collection, separation and packaging of the naphthalene-based water reducing agent with low sodium sulfate content.

[0037] It should be noted that if the power of the pump body 9 is insufficient in the actual working condition, a spare pump body can be additionally set on the finished product tank 6 to make up for the insufficient power. And discharge valves are arranged on the sides of the first collection tank 4 or the second collection tank 5, and the discharge valves can discharge the sodium sulfate crystals in the crystal chamber 17. The discharge valves are not shown in the figure and are common existing technologies, so they will not be elaborated here.

[0038] Example 5: Reference Figure 6 As shown in [reference], a circulation pump body 26 is also connected to the side of the first collection tank 4 or the second collection tank 5. Switch valves 25 are arranged at the connection points between the circulation pump body 26 and the first collection tank 4 and the second collection tank 5. The switch valves 25 can use electric valves. A circulation pipeline 27 is also arranged on the circulation pump body 26, and the circulation pipeline 27 is communicated with the naphthalene-based water reducing agent feed pipe 8. In the present invention, the concentration transmitter is arranged in the first collection tank 4 and / or the second collection tank 5. When the concentration transmitter detects that the sodium sulfate content in the naphthalene-based water reducing agent in the first collection tank 4 or the second collection tank 5 does not reach the specified standard, the corresponding switch valve 25 connected to the first collection tank 4 or the second collection tank 5 will be opened, and then the circulation pump body 26 will be started to pump the naphthalene-based water reducing agent in the first collection tank 4 or the second collection tank 5 into the naphthalene-based water reducing agent feed pipe 8 for recycling treatment until the sodium sulfate content in the naphthalene-based water reducing agent reaches the standard, and then the corresponding solenoid valve will be opened to make the naphthalene-based water reducing agent enter the finished product tank 6.

[0039] It should be noted that a one-way valve for the naphthalene-based water reducing agent in the circulation pipeline 27 to enter the naphthalene-based water reducing agent feed pipe 8 unidirectionally is arranged at the connection point between the circulation pipeline 27 and the naphthalene-based water reducing agent feed pipe 8 to prevent the naphthalene-based water reducing agent from flowing back.

[0040] The present invention also provides a method for controlling the pressure of naphthalene-based water reducer, which is specifically achieved through the naphthalene-based water reducer feed pipe 8 and the pump body 9. When the pump body 9 pumps the naphthalene-based water reducer into the naphthalene-based water reducer feed pipe 8 and the naphthalene-based water reducer inlet pipe 14, due to the pumping force of the pump body 9, the pressure of the naphthalene-based water reducer can be controlled between 0.2 and 8 Mpa. By adjusting the diameter and the number of the naphthalene-based water reducer feed pipe 8 and the naphthalene-based water reducer inlet pipe 14, the pressure of the naphthalene-based water reducer in the naphthalene-based water reducer inlet pipe 14 can be controlled between 2 and 4 Mpa. Therefore, there is no need for an additional pressure control mechanism to control the pressure of the naphthalene-based water reducer, so that the pressure of the naphthalene-based water reducer in the naphthalene-based water reducer inlet pipe 14 is exactly controlled within the appropriate conditions.

[0041] During actual production, since there are three naphthalene-based water reducer inlet pipes 14, if it is necessary to keep the pressure of the naphthalene-based water reducer in all three naphthalene-based water reducer inlet pipes 14 exactly between 2 and 4 Mpa, and when controlling the degree of cooling of the naphthalene-based water reducer, there may be a situation where the naphthalene-based water reducer is introduced into two naphthalene-based water reducer inlet pipes 14 simultaneously or only into one naphthalene-based water reducer inlet pipe 14. Therefore, when the naphthalene-based water reducer is introduced into two naphthalene-based water reducer inlet pipes 14 simultaneously or only into one naphthalene-based water reducer inlet pipe 14, with the power of the pump body 9 remaining unchanged, the pressure of the naphthalene-based water reducer in these two or one naphthalene-based water reducer inlet pipes 14 will be greater than 2 - 4 Mpa. If it is necessary to prepare the naphthalene-based water reducer at exactly the right pressure, an additional pressure reducing mechanism needs to be provided on the naphthalene-based water reducer inlet pipe 14.

[0042] Therefore, as shown in Figure 4 and Figure 5 the pressure reducing mechanism includes a flow blocking ring 20. A magnetic positioning block 22 is fixedly arranged inside the flow blocking ring 20, and an electromagnetic fixing block 21 is fixedly arranged on the outer ring of the naphthalene-based water reducer inlet pipe 14. When the electromagnetic fixing block 21 is activated, the magnetic positioning block 22 is adsorbed and positioned by the electromagnetic fixing block 21, and the position of the flow blocking ring 20 inside the naphthalene-based water reducer inlet pipe 14 remains unchanged. Therefore, it will not significantly affect the pressure of the naphthalene-based water reducer in the naphthalene-based water reducer inlet pipe 14.

[0043] At both ends of the flow blocking ring 20, a first magnetic ring 23 is fixedly arranged. On the side of the first magnetic ring 23 away from the flow blocking ring 20, a second magnetic ring 24 is arranged. The magnetic poles between the first magnetic ring 23 and the second magnetic ring 24 repel each other. The second magnetic ring 24 is fixedly installed on the inner wall of the naphthalene-based water reducing agent inlet pipe 14, and there is a certain gap between the second magnetic ring 24 and the first magnetic ring 23. When the electromagnetic fixing block 21 is closed, since the magnetic positioning block 22 loses the force adsorbed and fixed by the electromagnetic fixing block 21, the flow blocking ring 20 can move in the naphthalene-based water reducing agent inlet pipe 14 under the impact of the naphthalene-based water reducing agent. During the moving process, due to the repulsive magnetic action between the first magnetic ring 23 and the second magnetic ring 24, a process in which the flow blocking ring 20 reciprocates in the naphthalene-based water reducing agent inlet pipe 14 is formed. During this reciprocating movement process, the pressure of the naphthalene-based water reducing agent in the naphthalene-based water reducing agent inlet pipe 14 is reduced.

[0044] An appropriate number of pressure reducing mechanisms are arranged on the naphthalene-based water reducing agent inlet pipe 14, and a pressure sensor 15 for detecting the pressure of the naphthalene-based water reducing agent is arranged inside the naphthalene-based water reducing agent inlet pipe 14. The control chip is connected between the pressure sensor 15 and multiple electromagnetic fixing blocks 21. When the pressure sensor 15 detects that the pressure of the naphthalene-based water reducing agent in the naphthalene-based water reducing agent inlet pipe 14 is not within the set range, one of the electromagnetic fixing blocks 21 can be controlled to open to achieve the purpose of reducing the pressure of the naphthalene-based water reducing agent. Then the pressure sensor 15 detects the pressure of the naphthalene-based water reducing agent again. If it is still not within the set range, one more electromagnetic fixing block 21 is continuously controlled to open to continue reducing the pressure of the naphthalene-based water reducing agent. Such a cycle is carried out until the pressure of the naphthalene-based water reducing agent in the naphthalene-based water reducing agent inlet pipe 14 is controlled within the range of 2 - 4 Mpa.

[0045] In summary, a pressure reducing mechanism is provided in the present invention, which can be used in combination with special equipment to well control the pressure of the naphthalene-based water reducing agent in the three naphthalene-based water reducing agent inlet pipes 14.

[0046] Moreover, during the reciprocating movement of the flow blocking ring 20, the key positions of the naphthalene-based water reducing agent inlet pipe 14 can also be dredged to avoid crystallization or blockage of the inner wall of the naphthalene-based water reducing agent inlet pipe 14. Secondly, the method provided by the present invention is environmentally friendly and energy-saving. Compared with the method of removing sulfates by the desulfation method commonly used in industry, the operation is simple and easy to implement, and it is easy to industrialize. The crystallized sodium sulfate can be recycled, there are no waste materials and no consumable materials. At the same time, the production cost is greatly reduced, and the environmental pollution is reduced. Again, the naphthalene-based water reducer is transported through the tortuous naphthalene-based water reducer introduction pipe 14, which can replace the conventional stirring method. Stirring can, on the one hand, accelerate the growth of crystals and the formation of crystal nuclei; on the other hand, if the naphthalene-based water reducer liquid is always stirred, the supersaturated feed liquid is likely to generate too many crystal nuclei, making the crystallized sodium sulfate crystal material too fine and not easy to settle. Therefore, the preparation method and special equipment for naphthalene-based water reducer with low sodium sulfate content of the present invention can comprehensively control the crystallization temperature, efficiency, pressure, separation and collection of naphthalene-based water reducer with low sodium sulfate content, enabling the rapid precipitation of sodium sulfate crystals and quickly, stably and conveniently obtaining naphthalene-based water reducer with low sodium sulfate content. Finally, after adding an attachment layer at the bottom of the reaction kettle, the present invention can not only prevent the blockage of the cold air inlet pipe and the naphthalene-based water reducer outlet pipe, making it difficult for sodium sulfate to crystallize on the kettle wall, but also make it easier to remove the crystallized sodium sulfate.

Claims

1. A method for preparing a low sodium sulfate naphthalene-based water reducer, which is used to prepare a low sodium sulfate naphthalene-based water reducer, characterized in that: The low sodium sulfate naphthalene water reducer is prepared by using special equipment, and the preparation conditions are: -10°C or below; 2-4Mpa pressure; the sodium sulfate content in the low sodium sulfate naphthalene water reducer is between 0.05% and 10%wt; The dedicated equipment comprises a reaction kettle (1), wherein a naphthalene-based water-reducing agent introduction pipe (14) is arranged in the reaction kettle (1) for introducing a naphthalene-based water-reducing agent, and a refrigerant is stored in the reaction kettle (1), and the refrigerant completely immerses the naphthalene-based water-reducing agent introduction pipe (14); The naphthalene-based water-reducing agent is cooled by the refrigerant while flowing through the naphthalene-based water-reducing agent introduction pipe (14).

2. The method for preparing a low sodium sulfate naphthalene water reducing agent according to claim 1, wherein: Three naphthalene-based water-reducing agent introduction pipes (14) are provided, and the naphthalene-based water-reducing agent introduction pipes (14) are arranged in a zigzag manner.

3. The method for preparing a low sodium sulfate naphthalene water reducing agent according to claim 1, wherein: The special equipment further comprises a raw material tank (7), the raw material tank (7) being used to store a naphthalene-based water-reducing agent liquid for normal temperature construction, wherein the initial concentration of sodium sulfate in the naphthalene-based water-reducing agent liquid for normal temperature construction is 7-20%wt; The raw material tank (7) is provided with a pump body (9) for conveying the naphthalene-based water-reducing agent liquid for normal temperature construction into the naphthalene-based water-reducing agent introduction pipe (14).

4. The method for preparing a low sodium sulfate naphthalene water reducing agent according to claim 1, wherein: The dedicated equipment further comprises a first collecting tank (4) and a second collecting tank (5); a first collecting pipe (10) or a second collecting pipe (11) respectively connected to the first collecting tank (4) or the second collecting tank (5) is arranged below the reaction kettle (1); and a solenoid valve (16) is arranged on the first collecting pipe (10) or the second collecting pipe (11).

5. The method for preparing a low sodium sulfate naphthalene water reducing agent according to claim 4, characterized in that: The first collecting tank (4) and the second collecting tank (5) are both provided with a filter layer (18), the upper part of the filter layer (18) is a crystal chamber (17), and the lower part of the filter layer (18) is a liquid chamber (19).

6. The method for preparing a low sodium sulfate naphthalene water reducing agent according to claim 5, characterized in that: The special equipment further comprises a finished product tank (6), which is connected to the liquid chamber (19).

7. The method for preparing a low sodium sulfate naphthalene water reducing agent according to claim 4, characterized in that: The first collecting tank (4) and the second collecting tank (5) are both provided with a concentration transmitter for detecting the content of sodium sulfate in the naphthalene-based water reducing agent; The first collecting tank (4) and the second collecting tank (5) are connected to a circulation pump body (26) connected to the liquid chamber (19), a switch valve (25) is provided at the connection point, and the circulation pump body (26) is also provided with a circulation pipeline (27) for circulatedly supplying naphthalene-based water reducer to the naphthalene-based water reducer inlet pipe (14).

8. The method for preparing a low sodium sulfate naphthalene-based water reducer according to claim 1, characterized in that: The refrigerant in the reaction kettle (1) circulates to perform refrigeration.

9. The method for preparing a low sodium sulfate naphthalene water reducing agent according to claim 1, characterized in that: The three naphthalene-based water-reducing agent inlet pipes (14) are each provided with an electronic control valve.

10. The method for preparing a low sodium sulfate naphthalene-based water reducer according to claim 1, characterized in that: The naphthalene-based water-reducing agent inlet pipe (14) is provided with a plurality of pressure-reducing mechanisms, the pressure-reducing mechanisms comprising a flow-blocking ring (20), a magnetic positioning block (22) being fixedly arranged inside the flow-blocking ring (20), and an electromagnetic fixing block (21) being fixedly arranged at the outer ring of the naphthalene-based water-reducing agent inlet pipe (14), the magnetic positioning block (22) and the electromagnetic fixing block (21) being attracted and fixed to each other; A first magnetic ring (23) is fixedly arranged at both ends of the flow-blocking ring (20); a second magnetic ring (24) is arranged on a side of the first magnetic ring (23) away from the flow-blocking ring (20); the magnetic poles of the first magnetic ring (23) and the second magnetic ring (24) repel each other; the second magnetic ring (24) is fixedly mounted on the inner wall of the naphthalene-based water-reducing agent introduction pipe (14); and a gap is left between the second magnetic ring (24) and the first magnetic ring (23).

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