Device for reducing acid escape in waste acid concentration process

Abstract

The utility model discloses a device for reducing acid escape in a waste acid concentration process, which belongs to the technical field of waste acid concentration and comprises a stock solution tank, a preheater, an evaporator, a main separator, a scrubber tower main body, a main condenser, a condenser gas-liquid separator, a condensed water tank and a concentrated solution tank. According to the device and system for reducing acid escape in the waste acid concentration process, single-effect forced circulation evaporation is adopted, the evaporation temperature difference is large, the treatment difficulty is reduced, the operation efficiency is improved, waste acid concentration and recovery are achieved, heat exchange bodies are stacked in a building block mode, the impact and vibration resistance is good, and disassembly and cleaning are convenient; according to the system, acid tail gas pollution is avoided, the system is high in automation degree and higher in safety coefficient for highly corrosive liquid, and by arranging the discharging pump, materials can be pumped into the concentrated liquid tank and can be stored and collected.

Description

Technical Field

[0001] The utility model relates to the technical field of waste acid concentration, and more specifically, it relates to a device for reducing acid escape during the waste acid concentration process. Background Art

[0002] Currently, in many chemical industrial production processes, relatively dilute waste sulfuric acid is generated. Treating this waste liquid is becoming increasingly difficult and expensive. The concentration and recovery of waste sulfuric acid, as well as acid escape during the evaporation process, have become problems that many enterprises urgently need to solve. On the one hand, in order to ensure production, the waste sulfuric acid must be treated. On the other hand, the resulting environmental pollution and protection issues also need to be addressed. Currently, the main methods for sulfuric acid concentration are as follows: pot concentration, combustion concentration, high-temperature concentration method, and low-temperature concentration method, etc. The sulfuric acid recovery rate of such methods is not high, and the pollution is serious. Therefore, the utility model designs a device for reducing acid escape during the waste acid concentration process, adding a specially designed gas washing device at the steam outlet, which can form an efficient and interlocking mist removal flow field, reducing the amount of acid vapor escape, so as to solve the problems existing in the prior art. In this way, the costs of raw materials and wastewater treatment are saved, and it is beneficial to environmental protection. This process is a continuous process, with convenient operation, energy consumption savings, investment savings, few auxiliary equipment, a compact device, a small floor area, and the discharged condensate water meeting the discharge standards, protecting the ecological environment while improving productivity. Summary of the Utility Model

[0003] (I) Technical Problems to be Solved

[0004] Aiming at the deficiencies of the prior art, the purpose of the utility model is to provide a device for reducing acid escape during the waste acid concentration process, which has the characteristics of a continuous process, convenient operation, energy consumption savings, investment savings, few auxiliary equipment, a compact device, and a small floor area.

[0005] (II) Technical Solutions

[0006] To achieve the above object, the utility model provides a device for reducing acid escape during waste acid concentration, which includes a stock solution tank, a preheater, an evaporator, a main separator, a scrubber tower body, a main condenser, a condenser gas-liquid separator, a condensate tank and a concentrated liquid tank. The stock solution tank is communicated with the preheater, the preheater is communicated with the evaporator, the evaporator is communicated with the main separator. A separator demister and a baffle cleaning spray head are arranged at the top of the main separator. A tower section is arranged inside the scrubber tower body, and an on-line flushing atomizer and a packing layer are arranged inside the tower section. The tower section is communicated with the main separator. A wire mesh cleaning spray head and a wire mesh demister are arranged on the inner side of the scrubber tower body. The scrubber tower body is communicated with the main condenser. A steam discharge port is arranged between the scrubber tower body and the main condenser. The main condenser is communicated with the condenser gas-liquid separator. A material circulation pump is arranged between the main separator, the evaporator and the preheater. A reflux pipe is arranged between the material circulation pump and the main separator. The material circulation pump is communicated with the concentrated liquid tank. A discharge pump is arranged between the material circulation pump and the concentrated liquid tank.

[0007] When using a device for reducing acid escape during waste acid concentration of this technical solution, the system adopts single-effect forced circulation evaporation, with a large evaporation temperature difference, which reduces the treatment difficulty, improves the operation efficiency, realizes the concentration and recovery of waste acid, stacks into a heat exchanger in a modular way, has good shock and vibration resistance, is convenient for disassembly and cleaning, etc. Through steam washing, the acid recovery rate is improved, avoiding acid tail gas pollution. This system has a high degree of automation and a higher safety factor for strongly corrosive liquids. By setting a discharge pump, the material can be pumped into the concentrated liquid tank, and the material can be stored and collected.

[0008] Further, a feed pump is arranged between the stock solution tank and the preheater, a vacuum pump is arranged on one side of the condenser gas-liquid separator, and a drain pump is arranged on one side of the condensate tank.

[0009] Further, a scrubber tower circulation pump is arranged between the scrubber tower body, the tower section and the main separator.

[0010] Further, the stock solution tank is a fiberglass reinforced plastic tank body, and the preheater and the evaporator are both graphite tube heat exchangers.

[0011] Further, the main separator is a steel-lined enamel separator, and the separator demister is a baffle demister.

[0012] Further, both the baffle cleaning spray head and the wire mesh cleaning spray head are 360-degree rotating spray heads. The condenser gas-liquid separator, the condensate tank, the scrubber tower body, the tower section and the scrubber tower body are made of rolled steel plates, and the concentrated liquid tank is made of fiberglass reinforced plastic.

[0013] (III) Beneficial effects

[0014] In summary, the utility model has the following beneficial effects:

[0015] 1. The system adopts single-effect forced circulation evaporation, with a large evaporation temperature difference, which reduces the treatment difficulty, improves the operation efficiency, realizes the concentration and recovery of waste acid, and is stacked into a heat exchanger in a modular manner, with good impact and vibration resistance, easy disassembly and cleaning, etc. Through steam washing, the acid recovery rate is improved, and acid tail gas pollution is avoided;

[0016] 2. The automation degree of this system is high. For strongly corrosive liquids, the safety factor is higher. By setting a discharge pump, the material can be pumped into the concentrated liquid tank, and the material can be stored and collected. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for describing the specific embodiments or the prior art. Obviously, the drawings in the following description are only one embodiment of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 It is a process schematic diagram of the present utility model.

[0019] The reference signs in the drawings are:

[0020] 1. Raw liquid tank; 2. Feed pump; 3. Preheater; 4. Evaporator; 5. Material circulation pump; 6. Main separator; 7. Separator demister; 8. Baffle cleaning spray head; 9. Online rinsing atomizer; 10. Packing layer; 11. Tower section; 12. Scrubbing tower body; 13. Wire mesh cleaning spray head; 14. Wire mesh demister; 15. Scrubbing tower circulation pump; 16. Return pipe; 17. Steam exhaust port; 18. Main condenser; 19. Condenser gas-liquid separator; 20. Vacuum pump; 21. Condensate tank; 22. Drainage pump; 23. Discharge pump; 24. Concentrated liquid tank. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] In order to make the technical means, creative features, achieved purposes and functions of the present utility model easy to understand, the technical solutions in the specific embodiments of the present utility model will be clearly and completely described below to further illustrate the present utility model. Obviously, the described specific embodiments are only a part of the embodiments of the present utility model, rather than all the styles.

[0022] Example:

[0023] The following is a further detailed description of the present utility model in combination with the attached Figure 1 drawings.

[0024] Please refer toFigure 1 , the present utility model provides a technical solution: a device for reducing acid escape during waste acid concentration, which includes a stock solution tank 1, a preheater 3, an evaporator 4, a main separator 6, a scrubbing tower main body 12, a main condenser 18, a condenser gas-liquid separator 19, a condensate tank 21, and a concentrated liquid tank 24. The system adopts single-effect forced circulation evaporation, with a large evaporation temperature difference, reducing the treatment difficulty, improving the operation efficiency, realizing the recovery of waste acid concentration, stacking into a heat exchanger in a modular manner, having good shock and vibration resistance, being convenient for disassembly and cleaning, etc. Through steam washing, the acid recovery rate is improved, avoiding acid tail gas pollution. The stock solution tank 1 is connected to the preheater 3, the preheater 3 is connected to the evaporator 4, the evaporator 4 is connected to the main separator 6. A separator demister 7 and a baffle cleaning spray head 8 are arranged at the top of the main separator 6. An on-line rinsing atomizer 9 and a packing layer 10 are arranged inside the tower section 11 of the scrubbing tower main body 12. The tower section 11 is connected to the main separator 6. A wire mesh cleaning spray head 13 and a wire mesh demister 14 are arranged on the inner side of the scrubbing tower main body 12. The scrubbing tower main body 12 is connected to the main condenser 18. A steam exhaust port 17 is arranged between the scrubbing tower main body 12 and the main condenser 18. The main condenser 18 is connected to the condenser gas-liquid separator 19. A material circulation pump 5 is arranged between the main separator 6, the evaporator 4, and the preheater 3. A reflux pipe 16 is arranged between the material circulation pump 5 and the main separator 6. The material circulation pump 5 is connected to the concentrated liquid tank 24. A discharge pump 23 is arranged between the material circulation pump 5 and the concentrated liquid tank 24. The automation degree of this system is high, and for strongly corrosive liquids, the safety factor is higher. By setting the discharge pump 23, the material can be pumped into the concentrated liquid tank 24, and the material can be stored and collected.

[0025] Specifically, a feed pump 2 is arranged between the stock solution tank 1 and the preheater 3. A vacuum pump 20 is arranged on one side of the condenser gas-liquid separator 19. A drain pump 22 is arranged on one side of the condensate tank 21. A scrubbing tower circulation pump 15 is arranged between the scrubbing tower main body 12, the tower section 11, and the main separator 6.

[0026] By adopting the above technical solution, by setting the feed pump 2, it is convenient to pump the material into the preheater 3. By setting the drain pump 22, the water in the condensate tank 21 can be discharged and treated.

[0027] Specifically, the stock solution tank 1 is a fiberglass-reinforced plastic tank body, the preheater 3 and the evaporator 4 are both graphite tube heat exchangers, the main separator 6 is a steel-lined enamel separator, and the separator demister 7 is a baffle demister.

[0028] By adopting the above technical solution, by setting the stock solution tank 1 as a fiberglass-reinforced plastic tank body, the strength of the stock solution tank 1 can be ensured. By setting the main separator 6 as a steel-lined enamel separator, the use effect of the main separator 6 can be ensured.

[0029] Specifically, the baffle cleaning nozzle 8 and the wire mesh cleaning nozzle 13 are both 360-degree rotating nozzles. The condenser gas-liquid separator 19, the condensate tank 21, the scrubber main body 12, the tower section 11 and the scrubber main body 12 are made of rolled steel plates, and the concentrated liquid tank 24 is made of fiberglass.

[0030] By adopting the above technical solution, by setting the baffle cleaning nozzle 8 and the wire mesh cleaning nozzle 13 as 360-degree rotating nozzles, the spraying range can be ensured. By setting the condenser gas-liquid separator 19, the condensate tank 21, the scrubber main body 12, the tower section 11 and the scrubber main body 12 as rolled steel plates, the overall strength of the condenser gas-liquid separator 19, the condensate tank 21, the scrubber main body 12, the tower section 11 and the scrubber main body 12 can be ensured.

[0031] The working principle of the present utility model is as follows:

[0032] S1. First, the feed pump 2 pumps the normal-temperature liquid in the raw liquid tank 1 through the preheater 3. After the material recovers heat with the primary steam condensate, the feed temperature is increased to 70-90 °C.

[0033] S2. The preheated material enters the circulating evaporation system. The 110-130 °C saturated fresh steam provides heat source for the evaporator 4. The liquid is continuously circulated in the system by the material circulating pump 5. When the liquid concentration reaches the set concentration of 50%-60%, the concentrated liquid is discharged through the discharge pump 23 and enters the concentrated liquid tank 24.

[0034] S3. The secondary steam generated in the main separator 6 rises. During the rising process of the steam, buoyancy is generated on the droplets. The flow rate of the steam rising in the main separator 6 is controlled at 2 - 4 m / s to reduce the droplet entrainment amount. The relatively small droplets inevitably float up and touch the separator demister 7 at the top of the main separator 6. After the small droplets gather on the separator demister 7, they sink due to gravity and return to the liquid level of the main separator 6. When shutting down for cleaning the efficiency, the baffle cleaning nozzle 8 can be opened for washing. The secondary steam after primary purification enters the scrubbing tower main body 12 through the secondary pipeline for scrubbing treatment. 3 - 5 online scrubbing atomizers 9 are arranged in the scrubbing tower section 11. The scrubbing water for online spraying atomization aggregates with the tiny droplets carried by the secondary steam. At the same time, a packing layer 10 is arranged below the online scrubbing atomizer 9 to increase the gas-liquid contact area and enhance the scrubbing effect. After scrubbing, the secondary steam enters the scrubbing tower main body 12 through the central pipe of the tower section 11, and the scrubbing water is separated by relying on the centrifugal force generated by the baffle. Then it rises to the built-in wire mesh demister 14 for the last step of droplet separation. The purified secondary steam enters the condenser through the secondary steam exhaust port 17. The scrubbing water in the tower is transported to the tower section 11 for spraying by the scrubbing tower circulation pump 15 to achieve circulating scrubbing. The residual water after scrubbing is periodically returned to the main separator 6 for continuous evaporation. Similarly, the wire mesh demister 14 also needs to be washed by opening the wire mesh cleaning nozzle 13 when shutting down for cleaning and disinfection. The purified steam enters the main condenser 18 for condensation. The condensed water and non-condensable gas enter the condenser gas-liquid separator 19 for separation, and then the condensed water is discharged into the condensate tank 21 and finally discharged from the system through the drain pump 22. The non-condensable gas is extracted by the vacuum pump 20.

[0035] This specific embodiment is only an explanation of the present invention, and it is not a limitation of the present invention. After reading this specification, those skilled in the art can make modifications to this embodiment without creative contributions according to needs, but as long as it is within the scope of the claims of the present invention, it is protected by the patent law.

Claims

1. A device for reducing acid escape in a waste acid concentration process, comprising a raw liquid tank (1), a preheater (3), an evaporator (4), a main separator (6), a scrubber tower body (12), a main condenser (18), a condenser gas-liquid separator (19), a condensate tank (21) and a concentrated liquid tank (24), characterized in that: The raw liquid tank (1) is connected to the preheater (3), the preheater (3) is connected to the evaporator (4), the evaporator (4) is connected to the main separator (6), a separator demister (7) and a baffle cleaning nozzle (8) are arranged on the top of the main separator (6), a tower section (11) is arranged inside the gas scrubbing tower body (12), and an online elution atomizer (9) and a packing layer (10) are arranged inside the tower section (11); The tower section (11) is connected to the main separator (6); a screen cleaning nozzle (13) and a screen demister (14) are arranged inside the scrubbing tower body (12); the scrubbing tower body (12) is connected to the main condenser (18); a steam outlet (17) is arranged between the scrubbing tower body (12) and the main condenser (18); the main condenser (18) is connected to the condenser gas-liquid separator (19); a material circulation pump (5) is arranged between the main separator (6), the evaporator (4) and the preheater (3); a reflux pipe (16) is arranged between the material circulation pump (5) and the main separator (6); the material circulation pump (5) is connected to the concentrated liquid tank (24); and a discharge pump (23) is arranged between the material circulation pump (5) and the concentrated liquid tank (24).

2. The device for reducing acid escape in a waste acid concentration process according to claim 1, characterized in that: A feed pump (2) is provided between the raw liquid tank (1) and the preheater (3), a vacuum pump (20) is provided on one side of the condenser gas-liquid separator (19), and a drainage pump (22) is provided on one side of the condensate tank (21).

3. The device for reducing acid escape in a waste acid concentration process according to claim 1, characterized in that: A scrubbing tower circulation pump (15) is provided between the scrubbing tower body (12), the tower section (11) and the main separator (6).

4. The device for reducing acid escape in a waste acid concentration process according to claim 1, characterized in that: The raw liquid tank (1) is a glass fiber reinforced plastic tank body, and the preheater (3) and the evaporator (4) are both graphite tube heat exchangers.

5. The device for reducing acid escape in a waste acid concentration process according to claim 1, characterized in that: The main separator (6) is a steel-lined enamel separator, and the separator demister (7) is a baffle demister.

6. The device for reducing acid escape in a waste acid concentration process according to claim 1, characterized in that: The baffle cleaning nozzle (8) and the screen cleaning nozzle (13) are both 360-degree rotating nozzles. The condenser gas-liquid separator (19), the condensate tank (21), the gas scrubber body (12), the tower section (11) and the gas scrubber body (12) are made of rolled steel plates. The concentrate tank (24) is made of glass fiber reinforced plastics.

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