A conditioning tank for treating sodium cyanide by-product

Abstract

The utility model discloses a kind of preparation sodium cyanide byproduct processing with adjusting pool, including adjusting pool body and pool cover. Negative pressure air extraction port and emergency pressure relief component are equipped on pool cover, emergency pressure relief component is connected with the second pressure relief pipe of direct connection waste gas absorption tower by bursting disc with the first pressure relief pipe, burst pressure is set as 0.01-0.05MPa, realize the directional safe release of toxic gas when overpressure. The inner wall of adjusting pool body is equipped with multilayer composite anticorrosion lining, from inside to outside in turn be polyvinylidene fluoride hydrogen fluoride acid corrosion resistant plastic layer, glass fiber reinforced layer and epoxy asphalt anticorrosion layer, effectively resist the erosion of fluorine ion and other corrosion medium in cyanide-containing wastewater. The utility model is integrated emergency pressure relief and multilayer anticorrosion structure, improves the safety, anticorrosion durability and operation reliability of adjusting pool when processing virulent sodium cyanide byproduct.

Description

Technical Field

[0001] This utility model relates to the field of sodium cyanide production by-product treatment technology, specifically to an equalization tank for preparing sodium cyanide by-product treatment. Background Technology

[0002] Sodium cyanide is an important basic chemical raw material widely used in metallurgy, electroplating, and pharmaceutical industries. Its production inevitably generates byproduct wastewater containing high concentrations of cyanide. This wastewater is extremely toxic and must undergo strict treatment before discharge or reuse.

[0003] In cyanide-containing wastewater treatment processes, the equalization tank is a key facility in the pretreatment stage. Its function is to homogenize the water quality and quantity, providing stable conditions for subsequent advanced treatment (such as alkaline chlorination and ozone oxidation). However, existing equalization tanks used for treating sodium cyanide byproducts have revealed the following significant drawbacks during long-term operation:

[0004] 1. Significant Safety Risks: When cyanide-containing wastewater remains in the equalization tank, it may release highly toxic hydrogen cyanide gas due to fluctuations in water quality or uneven mixing. Traditional equalization tanks lack dedicated safety pressure relief channels. Once the pressure inside the tank abnormally increases or an unexpected reaction occurs, the toxic gas cannot be directed and safely discharged, and is very likely to leak at weak points in the tank structure, causing serious safety accidents and environmental pollution.

[0005] 2. Poor corrosion resistance: Sodium cyanide byproduct wastewater has a complex composition, often containing other corrosive media (such as fluoride ions and chloride ions) in addition to cyanide, which are highly corrosive to the tank structure. Conventional concrete tanks or single anti-corrosion coatings (such as ordinary epoxy asphalt) are prone to peeling and leakage under long-term corrosion, which not only shortens the equipment life but also causes toxic wastewater to seep into the ground, polluting the soil and groundwater.

[0006] Therefore, we propose an equalization tank for the preparation and treatment of sodium cyanide byproducts. Utility Model Content

[0007] (a) Technical problems to be solved

[0008] To address the shortcomings of existing technologies, this invention provides an equalization tank for treating sodium cyanide byproducts. By integrating a multi-layer composite anti-corrosion lining with an emergency pressure relief component directly connected to a waste gas tower, the inherent safety, corrosion resistance, and operational reliability of the equalization tank in treating highly toxic sodium cyanide byproducts are improved, effectively solving the problems in the background technology.

[0009] (II) Technical Solution

[0010] To achieve the above objectives, the technical solution adopted by this utility model is as follows: an equalization tank for treating sodium cyanide byproducts, comprising an equalization tank body and a tank cover covering the top of the equalization tank body, wherein the tank cover is provided with a negative pressure exhaust port connected to a waste gas treatment system, an aeration structure is installed at the bottom of the inner cavity of the equalization tank body, a waste liquid inlet pipe is installed on the upper part of the outer surface of one end of the equalization tank body, and a waste liquid discharge pipe is installed on the lower part of the outer surface of the other end of the equalization tank body, wherein both the waste liquid inlet pipe and the waste liquid discharge pipe are equipped with... Equipped with a butterfly valve, the inner wall of the regulating tank body is lined with a multi-layer composite anti-corrosion lining. The tank cover is a sealing cover made of fiberglass. Emergency pressure relief components are also provided at the left and right ends of the upper outer surface of the tank cover. The emergency pressure relief components include a first pressure relief pipe, a second pressure relief pipe, a rupture disc, and a clamping pressure ring. The upper end of the second pressure relief pipe is directly connected to the air inlet of the external waste gas absorption tower. The multi-layer composite anti-corrosion lining includes, from the inside out, a hydrofluoric acid-resistant plastic layer, a glass fiber reinforced layer, and an epoxy asphalt anti-corrosion layer.

[0011] Preferably, the number of emergency pressure relief components is two sets. In the two sets of emergency pressure relief components, the first pressure relief pipe is fixed on the left and right sides of the upper outer surface of the regulating pool body, and the first pressure relief pipe extends to the lower outer surface of the pool cover.

[0012] Preferably, the number of clamping pressure rings in one set of the emergency pressure relief assembly is two sets, the rupture disc is located between the two sets of clamping pressure rings, and the two sets of clamping pressure rings are respectively fixed to the upper outer surface of the first pressure relief pipe and the lower outer surface of the second pressure relief pipe.

[0013] Preferably, the burst pressure setting value of the rupture disc is in the range of 0.01MPa to 0.05MPa.

[0014] Preferably, the material of the hydrofluoric acid resistant plastic layer is polyvinylidene fluoride.

[0015] Preferably, the thickness of the hydrofluoric acid resistant plastic layer is 5 mm to 15 mm; the thickness of the glass fiber reinforced layer is 2 mm to 5 mm; and the thickness of the epoxy asphalt anticorrosion layer is 1 mm to 3 mm.

[0016] (III) Beneficial Effects

[0017] Compared with the prior art, this utility model provides an conditioning tank for treating sodium cyanide by-products, which has the following beneficial effects:

[0018] 1. This regulating tank for treating sodium cyanide byproducts integrates an emergency pressure relief component on the tank cover and connects the second pressure relief pipe of the component directly to the air inlet of an external waste gas absorption tower. When the pressure in the tank exceeds the set pressure (0.01MPa to 0.05MPa) of the rupture disc due to an accident, the rupture disc ruptures rapidly, and the high-pressure toxic gas can be directed and safely discharged to the waste gas absorption tower for centralized treatment. This completely avoids the risk of disorderly leakage of toxic gas or tank rupture and improves the inherent safety level of the equipment.

[0019] 2. This equalization tank for treating sodium cyanide byproducts comprises a multi-layered composite anti-corrosion lining on its inner wall, consisting of a hydrofluoric acid-resistant plastic layer (such as polyvinylidene fluoride), a glass fiber reinforcement layer, and an epoxy asphalt anti-corrosion layer. The design is optimized for the complex corrosive environment of sodium cyanide byproduct wastewater (especially fluoride ion corrosion). Each layer works synergistically: the inner polyvinylidene fluoride layer provides excellent chemical inertness, the middle glass fiber layer enhances overall mechanical strength and impermeability, and the outer epoxy asphalt layer ensures adhesion to the tank foundation and provides foundation protection. This effectively resists wastewater erosion, extends the service life of the equalization tank, and prevents leakage and pollution from toxic wastewater. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of an equalization tank for treating sodium cyanide byproducts according to this utility model.

[0021] Figure 2 This is a schematic diagram of the emergency pressure relief component in the regulating tank for the preparation of sodium cyanide by-products according to this utility model.

[0022] Figure 3 This is a partial structural schematic diagram of an equalization tank for treating sodium cyanide byproducts according to this utility model.

[0023] Figure 4 This is a partial cross-sectional schematic diagram of a multi-layer composite anti-corrosion lining in an equalization tank for preparing sodium cyanide by-products according to this utility model.

[0024] In the diagram: 1. Equalization tank body; 2. Tank cover; 3. Negative pressure exhaust port; 4. Emergency pressure relief assembly; 5. Waste liquid inlet pipe; 6. Waste liquid outlet pipe; 7. First pressure relief pipe; 8. Second pressure relief pipe; 9. Rupture disc; 10. Clamping ring; 11. Aeration structure; 12. Multi-layer composite anti-corrosion lining; 13. Epoxy asphalt anti-corrosion layer; 14. Glass fiber reinforcement layer; 15. Hydrofluoric acid resistant plastic layer. Detailed Implementation

[0025] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0026] like Figure 1-4 As shown, this utility model provides an conditioning tank for treating sodium cyanide by-products, including a conditioning tank body 1 and a tank cover 2 covering the top of the conditioning tank body 1.

[0027] The pool cover 2 is a sealed cover made of fiberglass. The pool cover 2 is equipped with a negative pressure exhaust port 3 that is connected to the exhaust gas treatment system (not shown in the figure). Under normal operating conditions, through negative pressure suction, the trace amounts of toxic gases (such as hydrogen cyanide) volatilized in the regulating pool are continuously discharged and sent to the exhaust gas treatment system for treatment, maintaining a slight negative pressure state in the pool and preventing gas from escaping.

[0028] To address potential abnormal operating conditions (such as a rapid increase in pressure within the pool due to uncontrolled reaction), two sets of emergency pressure relief components 4 are installed at both ends of the upper outer surface of the pool cover 2. Each set of emergency pressure relief components 4 includes a first pressure relief pipe 7, a second pressure relief pipe 8, a rupture disc 9, and a clamping pressure ring 10. The lower end of the first pressure relief pipe 7 penetrates the pool cover 2 and communicates with the inner cavity of the regulating pool body 1, while its upper end is fixedly mounted with the rupture disc 9 via the clamping pressure ring 10. The lower end of the second pressure relief pipe 8 is sealed and fixed to the upper surface of the rupture disc 9 via another clamping pressure ring 10, thereby clamping and fixing the rupture disc 9 between the two sets of clamping pressure rings 10. The upper end of the second pressure relief pipe 8 is directly connected to the air inlet of an external waste gas absorption tower (not shown in the figure). In this embodiment, the burst pressure setting value of the rupture disc 9 is in the range of 0.01 MPa to 0.05 MPa. When the pressure inside the pool is abnormal and exceeds the set value, the rupture disc 9 ruptures instantly. The high-pressure gas is directly and directionally introduced into the waste gas absorption tower for emergency treatment through the first pressure relief pipe 7, the ruptured rupture disc 9, and the second pressure relief pipe 8. This effectively avoids the risk of physical explosion or disorderly leakage of toxic gas that may be caused by the excessive pressure of the pool, and improves the safety of the equipment.

[0029] A waste liquid inlet pipe 5 for introducing cyanide-containing waste liquid is installed on the upper part of the outer surface of one end of the equalization tank body 1, and a waste liquid outlet pipe 6 for discharging homogenized waste liquid is installed on the lower part of the outer surface of the other end. Both the waste liquid inlet pipe 5 and the waste liquid outlet pipe 6 are equipped with butterfly valves (not labeled in the figure). An aeration structure 11 is installed at the bottom of the inner cavity of the equalization tank body 1 to stir the waste liquid in the tank, homogenize its water quality and quantity, and provide conditions for possible pre-oxidation treatment (this is prior art).

[0030] In view of the complex composition and highly corrosive nature of sodium cyanide byproduct wastewater (especially the potential presence of highly corrosive media such as fluoride ions), the inner wall of the equalization tank body 1 is equipped with a multi-layer composite anti-corrosion lining 12. For example... Figure 4 As shown, the multi-layer composite anti-corrosion lining 12 includes, from the inside out, a hydrofluoric acid resistant plastic layer 15, a glass fiber reinforced layer 14, and an epoxy asphalt anti-corrosion layer 13.

[0031] Specifically, the hydrofluoric acid-resistant plastic layer 15 is preferably made of polyvinylidene fluoride (PVDF), which comes into direct contact with wastewater. Utilizing the excellent resistance of PVDF to hydrofluoric acid, cyanide, and various chemical media, it provides the primary corrosion barrier. The thickness of this hydrofluoric acid-resistant plastic layer 15 is preferably 5 mm to 15 mm.

[0032] A glass fiber reinforcement layer 14 is disposed on the outside of the hydrofluoric acid resistant plastic layer 15, and its main function is to enhance the mechanical strength, impact resistance, and impermeability of the entire lining. The thickness of the glass fiber reinforcement layer 14 is preferably 2 mm to 5 mm.

[0033] The epoxy asphalt anticorrosion layer 13, as the outermost layer, is coated on the surface of the concrete or steel structure substrate of the regulating tank body 1. Its main function is to provide good adhesion and basic anticorrosion protection, preventing groundwater vapor and other substances from eroding the tank substrate. The thickness of the epoxy asphalt anticorrosion layer 13 is preferably 1 mm to 3 mm.

[0034] These three layers work together to form a highly efficient, durable, and targeted high-level anti-corrosion system, extending the service life of the equalization tank and effectively preventing leakage and pollution of toxic wastewater.

[0035] Working Principle: Wastewater containing sodium cyanide byproducts enters the equalization tank body 1 through the waste liquid inlet pipe 5. During normal operation, the negative pressure exhaust port 3 maintains a slight negative pressure inside the tank, and the aeration structure 11 operates intermittently to ensure uniform water quality. When the pressure inside the tank exceeds the set pressure of the rupture disc 9 due to abnormal conditions, the rupture disc 9 ruptures, and the high-pressure exhaust gas is directly discharged into the external exhaust gas absorption tower for emergency treatment through the emergency pressure relief component 4. The treated homogenized wastewater is sent to subsequent treatment processes through the waste liquid discharge pipe 6. The multi-layer composite anti-corrosion lining 12 provides continuous and effective anti-corrosion protection for the tank body throughout the entire process.

[0036] It should be noted that, in this document, relational terms such as first and second (number one, number two), etc., are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0037] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A regulating tank for treating sodium cyanide byproducts, comprising a regulating tank body (1) and a tank cover (2) covering the top of the regulating tank body (1), wherein the tank cover (2) is provided with a negative pressure exhaust port (3) connected to a waste gas treatment system, an aeration structure (11) is installed at the bottom of the inner cavity of the regulating tank body (1), a waste liquid inlet pipe (5) is installed on the upper part of the outer surface of one end of the regulating tank body (1), and a waste liquid discharge pipe (6) is installed on the lower part of the outer surface of the other end of the regulating tank body (1), wherein both the waste liquid inlet pipe (5) and the waste liquid discharge pipe (6) are equipped with butterfly valves, characterized in that: The inner wall of the regulating tank body (1) is provided with a multi-layer composite anti-corrosion lining (12). The tank cover (2) is a sealing cover made of fiberglass. Emergency pressure relief components (4) are also provided on the left and right ends of the upper outer surface of the tank cover (2). The emergency pressure relief components (4) include a first pressure relief pipe (7), a second pressure relief pipe (8), a rupture disc (9) and a clamping pressure ring (10). The upper end of the second pressure relief pipe (8) is directly connected to the air inlet of the external waste gas absorption tower. The multi-layer composite anti-corrosion lining (12) includes, from the inside to the outside, a hydrofluoric acid corrosion resistant plastic layer (15), a glass fiber reinforced layer (14) and an epoxy asphalt anti-corrosion layer (13).

2. The conditioning tank for treating by-products of sodium cyanide production according to claim 1, characterized in that: The number of emergency pressure relief components (4) is two sets. In the two sets of emergency pressure relief components (4), the first pressure relief pipe (7) is fixed on the left and right sides of the upper outer surface of the regulating pool body (1), and the first pressure relief pipe (7) extends to the lower outer surface of the pool cover (2).

3. The conditioning tank for treatment of sodium cyanide by-product according to claim 2, characterized in that: The number of clamping pressure rings (10) in one set of the emergency pressure relief assembly (4) is two sets. The rupture disc (9) is located between the two sets of clamping pressure rings (10), and the two sets of clamping pressure rings (10) are respectively fixed to the upper outer surface of the first pressure relief pipe (7) and the lower outer surface of the second pressure relief pipe (8).

4. The conditioning tank for treatment of sodium cyanide by-product according to claim 3, characterized in that: The burst pressure setting range of the rupture disc (9) is 0.01 MPa to 0.05 MPa.

5. The conditioning tank for treatment of sodium cyanide by-product according to claim 1, characterized in that: The material of the hydrofluoric acid resistant plastic layer (15) is polyvinylidene fluoride.

6. The conditioning tank for treatment of sodium cyanide by-product according to claim 5, characterized in that: The thickness of the hydrofluoric acid resistant plastic layer (15) is 5 mm to 15 mm; the thickness of the glass fiber reinforced layer (14) is 2 mm to 5 mm; and the thickness of the epoxy asphalt anticorrosion layer (13) is 1 mm to 3 mm.

Images