A system for dry handling of sodium sulfate in the tin smelting

Abstract

The utility model discloses a kind of tin smelting wind power carrying dry sodium sulfate's operation system, belong to non-ferrous metallurgy byproduct drying technical field.The operation system includes hopper, drying bed, discharge chute and product packaging line connected in turn;It further includes frequency conversion blower, first heat exchanger and tin smelting waste heat boiler, wherein, first heat exchanger is connected with drying bed, frequency conversion blower and tin smelting waste heat boiler respectively.The operation system of the present application can efficiently, energy-saving, low-loss, pollution-free wet sodium sulfate is deeply dried, and water resource and heat energy recycling is realized, while making full use of smelting plant waste heat, for reducing tin smelting cost, improving resource comprehensive utilization rate, reducing environmental pollution, promoting sodium sulfate byproduct value has urgent demand and important significance.

Description

Technical Field

[0001] This utility model relates to the field of drying technology for by-products in non-ferrous metal metallurgy, and more specifically to an operating system for drying sodium sulfate by wind power in tin smelting. Background Technology

[0002] In the tin smelting process, wastewater rich in sodium sulfate is generated during acid production. After evaporation, this wastewater yields sodium sulfate with a high moisture content. Sodium sulfate is a valuable industrial raw material, but sodium sulfate recovered from wastewater typically contains more than 8% moisture. This wet sodium sulfate has poor physical properties, readily absorbing moisture and agglomerating, causing significant difficulties in subsequent packaging, storage, transportation, and sales. This not only affects product quality and increases costs but also poses a risk of leakage and pollution. Therefore, it is essential to perform deep drying treatment on the wet sodium sulfate to significantly reduce its moisture content (typically to below 0.2%) to meet the requirements of industrial users.

[0003] Currently, common methods for drying sodium sulfate include hot air rotary kiln drying, fluidized bed drying, and belt drying. However, these traditional drying technologies generally suffer from high energy consumption, large losses, low efficiency, underutilization of resources, and the risk of secondary pollution. They fail to effectively utilize the waste heat generated during tin smelting (such as boiler steam waste heat) as a drying heat source, requiring a large amount of external energy (such as natural gas, oil, or electricity) to generate the necessary hot air, resulting in high operating costs. During drying and material transportation, fine sodium sulfate dust is easily carried away by the airflow, leading to high product loss rates and environmental pollution. Improper handling of the water vapor and entrained dust generated during drying can result in exhaust emissions, and direct discharge of condensate or washing water can cause water waste and potential wastewater pollution.

[0004] Therefore, how to develop a novel operating system for drying sodium sulfate is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0005] The present invention aims to at least partially solve one of the aforementioned technical problems in the prior art.

[0006] Therefore, one objective of this utility model is to provide an operating system for the pneumatic conveying and drying of sodium sulfate in tin smelting, comprising a hopper, a drying bed, a discharge trough, and a product packaging line connected in sequence.

[0007] It also includes a variable frequency blower, a first heat exchanger, and a tin smelting waste heat boiler, wherein the first heat exchanger is connected to the drying bed, the variable frequency blower, and the tin smelting waste heat boiler respectively.

[0008] Furthermore, the operating system for the aforementioned tin smelting wind-powered transport and drying of sodium sulfate also includes a circulating water tank, which is connected to the first heat exchanger.

[0009] Furthermore, the operating system for the above-mentioned tin smelting pneumatic conveying and drying of sodium sulfate also includes an exhaust hood, a dust collection bag, and a variable frequency induced draft fan, with the drying bed connected in sequence to the exhaust hood, the dust collection bag, and the variable frequency induced draft fan.

[0010] Furthermore, the operating system for the above-mentioned tin smelting pneumatic transport and drying of sodium sulfate also includes a second heat exchanger, which is connected to the variable frequency blower and the variable frequency induced draft fan respectively.

[0011] Furthermore, the aforementioned operating system for the pneumatic transport and drying of sodium sulfate in tin smelting also includes a plate and frame filter press, which is connected to a second heat exchanger.

[0012] Furthermore, the operating system for the aforementioned tin smelting pneumatic transport and drying of sodium sulfate also includes a production water tank, which is connected to a plate and frame filter press.

[0013] As can be seen from the above technical solution, compared with the prior art, this utility model discloses an operating system for pneumatically transporting and drying sodium sulfate in tin smelting. This operating system can efficiently, energy-savingly, with low loss and pollution-free deep drying of wet sodium sulfate, and realize the recycling of water resources and heat energy. At the same time, it makes full use of the waste heat of the smelter. It is of urgent need and great significance for reducing tin smelting costs, improving the comprehensive utilization rate of resources, reducing environmental pollution, and enhancing the value of sodium sulfate by-products. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0015] Figure 1 A schematic diagram of the operating system for pneumatically transporting and drying sodium sulfate in tin smelting provided by this utility model;

[0016] Among them, 1-hopper, 2-drying bed, 3-discharge chute, 4-product packaging line, 5-variable frequency blower, 6-first heat exchanger, 7-tin smelting waste heat boiler, 8-circulating water tank, 9-exhaust hood, 10-dust collection bag, 11-variable frequency induced draft fan, 12-second heat exchanger, 13-plate and frame filter press, 14-production water tank. Detailed Implementation

[0017] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0018] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0020] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0021] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0022] This utility model discloses an operating system for pneumatically transporting and drying sodium sulfate in tin smelting, such as... Figure 1As shown, it includes a hopper 1, a drying bed 2, a discharge chute 3, and a product packaging line 4 connected in sequence; it also includes a variable frequency blower 5, a first heat exchanger 6, and a tin smelting waste heat boiler 7, wherein the first heat exchanger 6 is connected to the drying bed 2, the variable frequency blower 5, and the tin smelting waste heat boiler 7 respectively.

[0023] In one embodiment, such as Figure 1 As shown, the operating system for the tin smelting wind-powered transport and drying of sodium sulfate also includes a circulating water tank 8, which is connected to the first heat exchanger 6.

[0024] In one embodiment, such as Figure 1 As shown, the operating system for drying sodium sulfate by air-powered conveying in tin smelting also includes an exhaust hood 9, a dust collection bag 10, and a variable frequency induced draft fan 11. The drying bed 2 is connected to the exhaust hood 9, the dust collection bag 10, and the variable frequency induced draft fan 11 in sequence.

[0025] In one embodiment, such as Figure 1 As shown, the operating system for drying sodium sulfate by air-powered transport in tin smelting also includes a second heat exchanger 12, which is connected to the variable frequency blower 5 and the variable frequency induced draft fan 11 respectively.

[0026] In one embodiment, such as Figure 1 As shown, the operating system for drying sodium sulfate by air transport in tin smelting also includes a plate and frame filter press 13, which is connected to the second heat exchanger 12.

[0027] In one embodiment, such as Figure 1 As shown, the operating system for the pneumatic conveying and drying of sodium sulfate in tin smelting also includes a production water tank 14, which is connected to a plate and frame filter press 13.

[0028] Example 1

[0029] Sodium sulfate (containing 12.2% water) from the wastewater treatment of a tin smelting and processing enterprise was used as the drying target. The drying method employed was as follows: Figure 1 The operating system shown, the method for drying sodium sulfate by pneumatic conveying in tin smelting specifically includes the following steps:

[0030] (1) The steam from the 80t tin smelting waste heat boiler 7 is used as a heat source and is exchanged with the cold air from the variable frequency blower 5 through the air duct into the first heat exchanger 6. After heat exchange, the air rises to 95°C and is blown into the surface of the drying bed 2, which is 7m long and 1m wide, through the air duct at the bottom of the drying bed 2.

[0031] Steam from the tin smelting waste heat boiler 7 undergoes heat exchange and its temperature drops below 30°C to form condensate, which flows into the circulating water pool 8 for reuse.

[0032] (2) Sodium sulfate containing 12.2% water in hopper 1 enters the first bed surface of drying bed 2 through the feed pipe, and is transported to the last bed surface of drying bed 2 by the hot air at the bottom of drying bed 2 to complete deep drying at the same time. The drying temperature is 95℃ and the drying time is 1.2h. It enters the product packaging line 4 through the discharge chute 3 for packaging and sale.

[0033] (3) The top of the drying bed 2 is tightly connected to four exhaust hoods 9. Under the action of the variable frequency fan 11, the exhaust hoods 9 form a negative pressure of -200Pa, which draws the hot air from the drying bed 2 and some powdered sodium sulfate into the dust collection bag 10.

[0034] Powdered sodium sulfate entering the dust collection bag 10 is returned to hopper 1 for further drying if the moisture content is ≥0.2%, and directly packaged and sold if the moisture content is <0.2%.

[0035] The hot air coming out of the dust collection bag 10 is introduced into the second heat exchanger 12 after passing through the variable frequency induced draft fan 11. The waste heat of the cooled gas is used to preheat the air blown into the first heat exchanger 6 by the blower. The condensate generated after cooling enters the plate and frame filter press 13. After recovering sodium sulfate, the water enters the production water pool 14 and is recycled as production water. The sodium sulfate is returned to the hopper 1 for drying and recovery.

[0036] Example 2

[0037] Sodium sulfate (containing 12.5% ​​water) from the wastewater treatment of a tin smelting and processing enterprise was used as the drying target, and the following method was employed: Figure 1 The operating system shown, the method for drying sodium sulfate by pneumatic conveying in tin smelting specifically includes the following steps:

[0038] (1) The steam from the 80t tin smelting waste heat boiler 7 is used as a heat source and is exchanged with the cold air from the variable frequency blower 5 through the air duct into the first heat exchanger 6. After heat exchange, the air rises to 95°C and is blown into the surface of the drying bed 2, which is 7m long and 1m wide, through the air duct at the bottom of the drying bed 2.

[0039] Steam from the tin smelting waste heat boiler 7 undergoes heat exchange and its temperature drops below 30°C to form condensate, which flows into the circulating water pool 8 for reuse.

[0040] (2) Sodium sulfate containing 12.2% water in hopper 1 enters the first bed surface of drying bed 2 through the feed pipe, and is transported to the last bed surface of drying bed 2 by the hot air at the bottom of drying bed 2 to complete deep drying at the same time. The drying temperature is 95℃ and the drying time is 1.2h. It enters the product packaging line 4 through the discharge chute 3 for packaging and sale.

[0041] (3) The top of the drying bed 2 is tightly connected to four exhaust hoods 9. Under the action of the variable frequency fan 11, the exhaust hoods 9 form a negative pressure of -200Pa, which draws the hot air from the drying bed 2 and some powdered sodium sulfate into the dust collection bag 10.

[0042] Powdered sodium sulfate entering the dust collection bag 10 is returned to hopper 1 for further drying if the moisture content is ≥0.2%, and directly packaged and sold if the moisture content is <0.2%.

[0043] The hot air coming out of the dust collection bag 10 is introduced into the second heat exchanger 12 after passing through the variable frequency induced draft fan 11. The waste heat of the cooled gas is used to preheat the air blown into the first heat exchanger 6 by the blower. The condensate generated after cooling enters the plate and frame filter press 13. After recovering sodium sulfate, the water enters the production water pool 14 and is recycled as production water. The sodium sulfate is returned to the hopper 1 for drying and recovery.

[0044] Performance testing

[0045] The moisture content, loss rate, and drying rate of sodium sulfate after drying in Examples 1-2 were calculated respectively, and the results are shown in Table 1.

[0046] Table 1. Moisture content, loss rate, and drying rate of sodium sulfate after drying in Examples 1-2.

[0047] sample Moisture content (%) of sodium sulfate Sodium sulfate loss rate (%) Drying rate (t / h) Example 1 <0.15 0.0007 4.5 Example 2 <0.12 0.0006 4.2

[0048] As shown in Table 1, the moisture content of the dried sodium sulfate in Examples 1-2 can be reduced to below 0.2%, and the loss rate is <0.001%.

[0049] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0050] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. An operating system for pneumatically transporting and drying sodium sulfate in tin smelting, characterized in that, It includes a hopper, a drying bed, a discharge trough, and a product packaging line connected in sequence; It also includes a variable frequency blower, a first heat exchanger, and a tin smelting waste heat boiler, wherein the first heat exchanger is connected to the drying bed, the variable frequency blower, and the tin smelting waste heat boiler.

2. The operating system for pneumatically transporting and drying sodium sulfate in tin smelting according to claim 1, characterized in that, It also includes a circulating water tank, which is connected to the first heat exchanger.

3. The operating system for pneumatically transporting and drying sodium sulfate in tin smelting according to claim 1, characterized in that, It also includes an exhaust hood, a dust collection bag, and a variable frequency induced draft fan, with the drying bed connected in sequence to the exhaust hood, the dust collection bag, and the variable frequency induced draft fan.

4. The operating system for pneumatically transporting and drying sodium sulfate in tin smelting according to claim 3, characterized in that, It also includes a second heat exchanger, which is connected to the variable frequency blower and the variable frequency induced draft fan respectively.

5. The operating system for pneumatically transporting and drying sodium sulfate in tin smelting according to claim 4, characterized in that, It also includes a plate and frame filter press, which is connected to the second heat exchanger.

6. The operating system for pneumatically transporting and drying sodium sulfate in tin smelting according to claim 5, characterized in that, It also includes a production water tank, which is connected to the plate and frame filter press.

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