Treatment system and treatment method for calcining industrial byproduct gypsum

Abstract

The invention relates to the technical field of harmless treatment of solid wastes, and particularly discloses a treatment system and a treatment method for calcining industrial byproduct gypsum. A flue gas purification mechanism; the multiple calcining treatment kilns are rotary kilns, feeding ports are formed in the calcining treatment kilns, air inlet pipes and exhaust pipes are arranged on one sides of the calcining treatment kilns, the air inlet pipes and the exhaust pipes are located at the ends, close to the feeding ports, of the calcining treatment kilns, the air inlet pipes communicate with the smoke chamber, and the exhaust pipes communicate with the smoke chamber. The exhaust pipe is communicated with the flue gas purification mechanism, an air inlet valve is arranged in the air inlet pipe, and an exhaust valve is arranged in the exhaust pipe; and the feeding mechanism is used for conveying phosphogypsum and can seal the feeding port. According to the method, the contact time of the flue gas and the phosphogypsum can be prolonged, so that the flue gas and the phosphogypsum can be in full contact, attached water and part of crystal water in the phosphogypsum can be rapidly removed, and the calcination treatment effect is enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of solid waste harmless treatment, in particular to a treatment system and method for calcining industrial by-product gypsum. BACKGROUND

[0002] The flue gas discharged from the ceramist kiln generally needs to be first subjected to dust removal and denitration in a smoke chamber, and then be subjected to dust removal by a dust removal device and water washing purification before being discharged into the atmosphere. In the dust removal device, the commonly used bag dust removal device requires that the temperature of the flue gas entering the device does not exceed 200 DEG C, and the temperature of the high-temperature flue gas after dust removal and denitration in the smoke chamber is still as high as 350 DEG C-550 DEG C. If the high-temperature flue gas is directly introduced into the bag dust removal device, the bag dust removal device will be damaged, and the waste heat of the high-temperature flue gas will also be wasted. The calcination harmless treatment of phosphogypsum requires a large amount of heat energy, so in order to realize the recycling of the waste heat of the high-temperature flue gas, a phosphogypsum calcination treatment kiln is usually arranged to introduce the high-temperature flue gas into the phosphogypsum calcination treatment kiln to pretreat the phosphogypsum before being discharged into the subsequent bag dust removal device.

[0003] Phosphogypsum is a by-product produced in the production process of wet-process phosphoric acid, and is an industrial waste residue. The main component of phosphogypsum is calcium sulfate dihydrate, which contains a small amount of free acid and phosphates, fluorides, heavy metals and other impurities. Due to the presence of these impurities, phosphogypsum cannot be directly used and needs to be pretreated to remove or reduce these harmful substances to meet the standard for safe use. The commonly used pretreatment is high-temperature calcination, which can remove these impurities and reduce environmental safety risks; calcination can also obtain hemihydrate gypsum or anhydrous gypsum, which can be used in the building materials industry, thereby realizing the conversion of waste into resources.

[0004] However, the existing phosphogypsum calcination treatment kiln is continuously rotating, thereby pushing the phosphogypsum to move from the feed port to the discharge port, and the high-temperature flue gas is introduced into the calcination treatment kiln from the end close to the discharge port of the phosphogypsum and discharged from the end close to the feed port of the phosphogypsum. The flue gas does not sufficiently contact the phosphogypsum, and can only remove the free water and part of the crystal water in the phosphogypsum, and cannot ensure the removal of the crystal water in the phosphogypsum, so the calcination effect is not good. SUMMARY

[0005] In order to enhance the calcination treatment effect of phosphogypsum, the present application provides a treatment system and method for calcining industrial by-product gypsum.

[0006] In a first aspect, the present application provides a treatment system for calcining industrial by-product gypsum, which adopts the following technical solution: A treatment system for calcining industrial by-product gypsum, comprising: a smoke chamber, the smoke chamber being used to communicate with a kiln body and being used to accommodate flue gas discharged from the kiln body; The flue gas purification mechanism is used for removing ash in flue gas. The calcination treatment kiln is arranged between the smoke chamber and the flue gas purification mechanism, and is provided with multiple and parallel arranged rotary kilns. One end of the rotary kiln is provided with a feeding port for conveying phosphogypsum, so that the phosphogypsum in the rotary kiln can be driven to move away from the feeding port when the rotary kiln rotates in one direction, and the phosphogypsum in the rotary kiln can be driven to move close to the feeding port when the rotary kiln rotates in the other direction. The rotary kiln is provided with a gas inlet pipe and a gas outlet pipe on one side, and the gas inlet pipe and the gas outlet pipe are both located at the end of the rotary kiln close to the feeding port. The gas inlet pipe is in communication with the smoke chamber, and the gas outlet pipe is in communication with the flue gas purification mechanism. The gas inlet pipe is provided with a gas inlet valve, and the gas outlet pipe is provided with a gas outlet valve. The feeding mechanism is arranged outside the feeding port, and is used for feeding the phosphogypsum into the rotary kiln or discharging the phosphogypsum in the rotary kiln, and can seal the feeding port.

[0007] By adopting the above technical scheme, the conveying direction of the phosphogypsum and the conveying direction of the flue gas are the same, so that the flue gas can fully contact with the phosphogypsum, thereby enhancing the cooling effect of the flue gas and the calcination pretreatment effect of the phosphogypsum. When the flue gas and the phosphogypsum in one rotary kiln reach the set amount, the feeding port of the rotary kiln can be sealed. At this time, the rotary kiln is still in a state of continuous rotation, so that the calcination time of the phosphogypsum can be prolonged, the phosphogypsum and the flue gas can be more fully contacted, thereby better removing the crystal water contained in the phosphogypsum, and enhancing the calcination effect. Since multiple rotary kilns are arranged in parallel, the flue gas in the smoke chamber can only be discharged into one of the rotary kilns at a time. Therefore, when the flue gas in one of the rotary kilns reaches the set amount and the rotary kiln is sealed, the flue gas in the smoke chamber can be discharged into the next rotary kiln. Therefore, while ensuring the calcination effect of the phosphogypsum, the processing system can continuously process the flue gas discharged from the smoke chamber, thereby ensuring the continuity of the flue gas cooling and the phosphogypsum pretreatment production.

[0008] Optionally, the feeding mechanism comprises a feeding cylinder, a connecting ring, a spiral push plate and a driving member. The feeding cylinder is coaxially arranged at the feeding port of the rotary kiln. One end of the feeding cylinder is closed, and the other end is in communication with the inside of the rotary kiln and is rotationally connected. The feeding cylinder is provided with a feeding pipe and a discharging pipe. The feeding pipe is provided with a feeding valve, and the discharging pipe is provided with a discharging valve. The connecting ring is rotationally arranged in the inside of the feeding cylinder. The spiral push plate is fixedly connected to the connecting ring. One side of the spiral push plate abuts against the inner wall of the feeding cylinder, so that when the connecting ring drives the spiral push plate to rotate, the material in the feeding cylinder can be pushed to move towards one end. The driving member is arranged on one side of the connecting ring, and is used for driving the connecting ring to rotate.

[0009] By adopting the technical scheme, the phosphogypsum can be put into the feeding cylinder through the feeding pipe, and then the rotating spiral push plate can convey the phosphogypsum in the feeding cylinder to the calcination treatment kiln; the material after the calcination treatment in the calcination treatment kiln can be conveyed to the feeding cylinder, and then discharged through the discharging pipe; since the entering and discharging of the material in the calcination treatment kiln are both realized through the feeding opening, the feeding and discharging share one opening, thereby reducing the connection of the device, improving the sealing performance of the calcination treatment kiln, and reducing the possibility of the phosphogypsum powder after boiling leaking out, which helps to protect the working environment.

[0010] Optionally, the driving member is a connecting rod, and the connecting rod is fixedly connected between the connecting ring and the inner wall of the calcination treatment kiln.

[0011] By adopting the technical scheme, when the calcination treatment kiln rotates, the connecting ring and the spiral push plate can be driven to rotate through the connecting rod, thereby realizing the conveying of the material in the feeding cylinder, and the rotation of the spiral push plate does not need to be provided with an additional power source, thereby helping to reduce the energy consumption.

[0012] Optionally, the gas inlet pipe and the gas outlet pipe are both fixedly connected to one end of the feeding cylinder away from the calcination treatment kiln, and the gas inlet pipe and the gas outlet pipe are both in communication with the inside of the feeding cylinder.

[0013] By adopting the technical scheme, the gas inlet pipe and the gas outlet pipe are both fixed on the feeding cylinder, so that the gas inlet pipe and the gas outlet pipe will not rotate with the calcination treatment kiln, which helps to ensure the smooth flow of the flue gas.

[0014] Optionally, the gas inlet pipe and the gas outlet pipe are both located at the top of the feeding cylinder.

[0015] By adopting the technical scheme, the phosphogypsum in the feeding cylinder can be prevented from entering the gas inlet pipe and the gas outlet pipe to cause blockage, thereby ensuring the smooth flow of the flue gas.

[0016] Optionally, an exhaust pipe and a fan are arranged between the gas outlet pipe and the flue gas purification mechanism.

[0017] By adopting the technical scheme, the exhaust pipe prolongs the flow path of the flue gas, and the fan can effectively control the flow speed and direction of the flue gas, so that the flue gas can be cooled again in the exhaust pipe before entering the flue gas purification mechanism, thereby avoiding the direct impact of the high-temperature flue gas on the flue gas purification mechanism to cause equipment damage.

[0018] Optionally, a bending portion is arranged on the exhaust pipe, the bending portion comprises a horizontal pipe and vertical pipes fixedly connected to both ends of the horizontal pipe, both the vertical pipes are located above the horizontal pipe, a dust collecting box is slidably detachably connected in the inside of the horizontal pipe, an opening of the dust collecting box faces upward, and a mounting hole is formed in the horizontal pipe for sliding the dust collecting box in and out.

[0019] By adopting the technical scheme, the design of the bending part makes the flue gas form a zigzag path in the flue pipe, effectively slows down the flue gas flow rate, prolongs the dust settling time in the flue gas, improves the dust trapping efficiency, and can realize preliminary dust removal treatment of the flue gas; the dust collecting box can be used to collect the dust in the flue gas, and since the dust collecting box is detachably arranged, it is convenient to clean the accumulated dust regularly, which helps to ensure stable operation of the system.

[0020] Optionally, the inner wall of the vertical pipe is provided with a plurality of stop blocks which are uniformly and spacedly arranged along the length direction of the vertical pipe, and the stop blocks are arranged obliquely.

[0021] By adopting the technical scheme, the stop blocks can block the flue gas, further prolong the residence time of the flue gas in the flue pipe, and help to enhance the preliminary dust removal effect and the cooling effect of the flue gas; at the same time, the stop blocks can also slow down the flue gas flow rate, further enhance the dust settling effect, reduce the working load of the flue gas purification mechanism, and prolong the service life thereof.

[0022] Optionally, the horizontal pipe is provided with a vibration motor.

[0023] By adopting the technical scheme, the vibration motor can effectively prevent the accumulation of dust in the flue pipe, improve the flue gas exhaust efficiency, and reduce the workload of cleaning and maintenance; the vibration generated by the vibration motor can also promote the flue dust attached to the inner wall of the flue pipe and the stop blocks to fall off, further enhancing the collection effect of the flue dust.

[0024] In a second aspect, the application provides a processing method, which adopts the following technical scheme: A processing method, using the processing system for calcining industrial by-product gypsum according to any one of the preceding aspects, comprising the following steps: a. opening the air inlet valve on the first calcining treatment kiln, the flue gas in the smoke chamber entering the first calcining treatment kiln through the air inlet pipe on the first calcining treatment kiln, the feeding mechanism feeding the phosphogypsum into the first calcining treatment kiln through the feeding port, and the first calcining treatment kiln rotating and continuously pushing the phosphogypsum inward; b. when the flue gas in the first calcining treatment kiln reaches the set amount, first opening the air inlet valve on the second calcining treatment kiln, then closing the air inlet valve on the first calcining treatment kiln, the flue gas in the smoke chamber entering the second calcining treatment kiln, and then feeding the phosphogypsum into the second calcining treatment kiln through the feeding mechanism; when the phosphogypsum in the first calcining treatment kiln reaches the set amount, the feeding mechanism stops feeding and closes the feeding port; c. The first calcining kiln is in a closed state, and the flue gas inside calcines the phosphogypsum. During the calcination, the flue gas in the smoke chamber enters the second calcining kiln, and the feeding mechanism feeds the phosphogypsum into the second calcining kiln. The second calcining kiln rotates and pushes the phosphogypsum inward. After the phosphogypsum in the first calcining kiln has been calcined for a period of time, the feeding mechanism opens the feeding port, and the first calcining kiln rotates in the opposite direction, conveying the material inside outward and discharging it through the feeding port and feeding mechanism. The exhaust valve on the first calcining kiln is opened to feed the flue gas into the flue gas purification mechanism. d. When the flue gas in the second calcining treatment kiln reaches the set amount, the air inlet valve on the third calcining treatment kiln is opened first, and then the air inlet valve on the second calcining treatment kiln is closed, and the flue gas in the smoke chamber enters the third calcining treatment kiln, and then the phosphogypsum is fed into the third calcining treatment kiln through the feeding mechanism; when the phosphogypsum in the second calcining treatment kiln reaches the set amount, the feeding mechanism stops feeding and closes the feeding port; e. The second calcining kiln is in a closed state, and the flue gas inside calcines the phosphogypsum. After calcining for a period of time, the feeding mechanism opens the feeding port, and the second calcining kiln rotates in the opposite direction to send out the internal material. The exhaust valve on the second calcining kiln is opened to send the flue gas into the flue gas purification mechanism.

[0025] By adopting the above technical solution, the flue gas and phosphogypsum can be fully contacted in the calcination treatment kiln, which also helps to extend the calcination treatment time of the flue gas on the phosphogypsum, thereby helping to remove the crystalline water in the phosphogypsum and enhance the calcination effect; there are multiple calcination treatment kilns, so that continuous treatment of the flue gas can be achieved.

[0026] In summary, this application has the following beneficial technical effects: 1. Flue gas and phosphogypsum are transported in the same direction in the calcination kiln, so that the flue gas and phosphogypsum can be more fully contacted; after the calcination kiln is closed, the contact time of flue gas and phosphogypsum can be further extended, so that the two can be more fully contacted, which helps to remove the crystal water in the phosphogypsum, thereby enhancing the effect of calcination pretreatment.

[0027] 2. The treatment system of the present application makes full use of the waste heat in the high-temperature flue gas to realize the calcination treatment of phosphogypsum through the waste heat in the high-temperature flue gas; furthermore, after the calcination treatment, the temperature of the flue gas is reduced, thereby reducing the impact of high temperature on the flue gas purification mechanism such as the bag dust collector, thereby ensuring the normal use of the flue gas purification mechanism.

[0028] 3. The entry and discharge of phosphogypsum are both completed through the feed port on the calcining kiln. After the phosphogypsum and flue gas are transported to the calcining kiln, the calcining kiln is closed, thereby enhancing the sealing of the calcining kiln. On the one hand, it can reduce the leakage of flue gas and ensure the processing temperature inside the calcining kiln, thereby ensuring the calcining effect and preventing the production of calcined defective products; on the other hand, it can also reduce the possibility of phosphogypsum powder in the calcining kiln leaking out after boiling, which helps to ensure the working environment.

[0029] 4. In this application, multiple calcination kilns are provided, which can realize the simultaneous calcination or sequential calcination of multiple types of gypsum, and can be selected according to needs, which is more applicable; the flue gas after calcination is purified and discharged uniformly, which helps to simplify the structure of the system.

[0030] 5. When one of the calcining kilns is closed, the flue gas in the smoke chamber can be passed into another calcining kiln. Thus, while ensuring the calcining effect of phosphogypsum, the flue gas discharged from the smoke chamber can be continuously treated, which helps to enhance the continuity of flue gas treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a front view of an embodiment of the present application; Figure 2 It is a schematic diagram of the overall structure of an embodiment of the present application; Figure 3 is a cross-sectional view of an embodiment of the present application; Figure 4 yes Figure 3 Enlarged schematic diagram of point A in the middle.

[0032] Figure numerals: 1. smoke chamber; 2. flue gas purification mechanism; 3. calcination treatment kiln; 31. feed port; 32. push plate; 33. driven gear ring; 4. feeding mechanism; 41. feed barrel; 42. connecting ring; 43. spiral push plate; 44. connecting rod; 5. feed pipe; 51. feed valve; 6. discharge pipe; 61. discharge valve; 7. air inlet pipe; 71. air inlet valve; 8. exhaust pipe; 81. exhaust valve; 9. exhaust pipe; 91. horizontal pipe; 911. mounting hole; 92. vertical pipe; 921. block; 10. ash box; 11. fan; 12. vibration motor; 13. drive motor; 14. driving gear. DETAILED DESCRIPTION

[0033] The following combination Figures 1-4 This application is described in further detail.

[0034] The present application discloses a system for processing gypsum produced as a by-product of calcination industry. Figure 1 and Figure 2The system for processing the by-product gypsum of calcination industry comprises a smoke chamber 1, a smoke purification mechanism 2, a calcination treatment kiln 3 and a feeding mechanism 4. The smoke chamber 1 is arranged at one end of the kiln body, and has a large cross section, i.e. the cross sectional area of the smoke passage is suddenly enlarged, so as to sharply reduce the flow speed of the smoke, which is helpful to accelerate the settlement of the dust particles in the smoke at a low flow speed. A baffle is arranged in the smoke chamber 1, so as to change the flow direction of the smoke. A hopper is arranged at the bottom of the smoke chamber 1, and is used to collect the settled dust. The smoke chamber 1 is connected with the inside of the kiln body, so that the smoke discharged from the kiln body can first flow into the smoke chamber 1 to be treated, so as to reduce the dust mixed in the smoke.

[0035] In this embodiment, the kiln body is a ceramsite calcination kiln, so that the heat in the high-temperature smoke discharged from the ceramsite calcination kiln can be recycled. In other embodiments, the kiln body can also be a calcination kiln made of other materials, such as a cement kiln or a lime kiln.

[0036] The smoke purification mechanism 2 comprises a bag-type dust collector, which is a dust filtering device and can remove the dust in the smoke. The working principle of the bag-type dust collector is that the filter bag made of fiber fabric such as textile filter cloth or non-woven felt is used to filter the dust-containing smoke. After the dust-containing smoke enters the dust collector from the air inlet, the larger dust particles will settle and fall into the hopper due to gravity, and the gas containing smaller dust will pass through the filter bag, so as to realize the purification of the smoke. The calcination treatment kiln 3 is connected between the smoke chamber 1 and the smoke purification mechanism 2, so that the smoke in the smoke chamber 1 can first flow into the calcination treatment kiln 3 to calcine and dehydrate the phosphogypsum in the calcination treatment kiln 3, and then the smoke after the calcination pretreatment flows into the smoke purification mechanism 2 to be treated, and the smoke after the dust removal can be discharged.

[0037] In this embodiment, three calcination treatment kilns 3 are arranged, and the axes of the three calcination treatment kilns 3 are arranged in parallel at intervals, so that the three calcination treatment kilns 3 are arranged side by side. In other embodiments, the calcination treatment kiln 3 can also be arranged in other numbers according to the needs.

[0038] The calcination treatment kiln 3 is a rotary kiln, and the calcination treatment kiln 3 comprises a kiln body in a cylindrical shape, and the kiln body is arranged in an inclined manner; a feeding port 31 is arranged at a lower end of the kiln body, so that the phosphogypsum and the flue gas can be fed into and discharged out of the kiln body through the feeding port 31. A spiral-shaped push plate 32 is fixedly connected to an inner wall of the kiln body, so that the material in the kiln body can be pushed to move to one end of the kiln body when the kiln body rotates. A driven gear ring 33 is coaxially fixedly connected to an outer wall of the kiln body, and a driving motor 13 and a driving gear 14 are arranged outside the kiln body; an output shaft of the driving motor 13 and the driving gear 14 are coaxially fixedly connected, and the driving gear 14 and the driven gear ring 33 are engaged, so that the kiln body can rotate and the material in the kiln body can move to one side of the kiln body after the driving motor 13 is started. When the material moves along the axial direction of the kiln body, the material can also move from the bottom of the kiln body to the top of the kiln body along the spiral-shaped push plate 32, and the material at the top of the kiln body can fall downward under the action of gravity, so that the material in the kiln body can be turned over while moving in the axial direction, and the phosphogypsum can be more fully contacted with the high-temperature flue gas, thereby enhancing the pretreatment effect.

[0039] With reference to Figure 3 and Figure 4 A feeding mechanism 4 is arranged outside the feeding port 31 of each calcination treatment kiln 3, and is used for feeding and discharging the material. The feeding mechanism 4 comprises a feeding cylinder 41, a connecting ring 42, a spiral push plate 43 and a driving member. The feeding cylinder 41 is a cylinder, and the feeding cylinder 41 and the kiln body are coaxially arranged; one end of the feeding cylinder 41 away from the kiln body is arranged in a closed manner, one end of the feeding cylinder 41 close to the kiln body is arranged in an open manner, and the end of the feeding cylinder 41 arranged in an open manner is rotationally connected to the kiln body, and the cavity in the feeding cylinder 41 is in communication with the inside of the kiln body.

[0040] The end of the feeding cylinder 41 away from the kiln body is provided with an inlet pipe 5 and an outlet pipe 6; the inlet pipe 5 is welded to the top wall of the feeding cylinder 41, and the outlet pipe 6 is welded to the bottom wall of the feeding cylinder 41; the inlet pipe 5 and the outlet pipe 6 are in communication with the inside of the feeding cylinder 41. The inlet pipe 5 is provided with an inlet valve 51 for controlling the opening and closing of the inlet pipe 5, and the outlet pipe 6 is provided with an outlet valve 61 for controlling the opening and closing of the outlet pipe 6.

[0041] The connecting rings 42 are coaxially arranged and spaced apart. The connecting rings 42 are located in the feeding cylinder 41, the outer diameter of the connecting rings 42 is the same as the inner diameter of the feeding cylinder 41, and the connecting rings 42 are rotationally connected with the feeding cylinder 41. The spiral push plate 43 is fixedly connected between the two connecting rings 42, and the outer side of the spiral push plate 43 abuts against the inner wall of the feeding cylinder 41. The driving member is a connecting rod 44, which is fixedly connected between the connecting ring 42 close to the kiln body and the inner wall of the kiln body. The connecting rod 44 is arranged in a circumferential array. Thus, when the kiln body rotates, the connecting rod 44 can drive the connecting ring 42 to rotate, and the connecting ring 42 drives the spiral push plate 43 to rotate, so that the spiral push plate 43 can push the material in the feeding cylinder 41 to move.

[0042] With reference to Figure 2 The top wall of the feeding cylinder 41 is also fixedly connected with an air inlet pipe 7 and an air outlet pipe 8, which are both in communication with the inside of the feeding cylinder 41. The air inlet pipe 7 and the air outlet pipe 8 are located on the two sides of the feeding cylinder 41, the air inlet pipe 7 is in communication with the smoke chamber 1, and the air outlet pipe 8 is in communication with the flue gas purification mechanism 2. Thus, the high-temperature flue gas in the smoke chamber 1 can first flow into the calcination treatment kiln 3 through the air inlet pipe 7 and the feeding cylinder 41 to calcine the phosphogypsum in the calcination treatment kiln 3; after calcination, the flue gas in the calcination treatment kiln 3 flows into the flue gas purification mechanism 2 through the feeding cylinder 41 and the air outlet pipe 8. The air inlet pipe 7 is provided with an air inlet valve 71, and the air outlet pipe 8 is provided with an air outlet valve 81.

[0043] With reference to Figure 3 Since a part of the gypsum powder is mixed in the flue gas after the calcination treatment of the phosphogypsum, directly discharging the calcined flue gas into the flue gas purification mechanism 2 can easily exceed the processing capacity of the flue gas purification mechanism 2, affecting the dust removal effect. In order to preliminarily remove dust from the calcined flue gas, an exhaust pipe 9 is arranged between the air outlet pipe 8 and the flue gas purification mechanism 2, and a fan 11 is arranged on the exhaust pipe 9.

[0044] The exhaust pipe 9 is provided with a bending part, which includes a horizontal pipe 91 and two vertical pipes 92 fixedly connected to the two ends of the horizontal pipe 91, and the vertical pipes 92 and the horizontal pipe 91 are in communication. The top end of one of the vertical pipes 92 is in communication with the air outlet pipe 8, and the top end of the other vertical pipe 92 is in communication with the flue gas purification mechanism 2. Thus, the flue gas after the calcination treatment in the calcination treatment kiln 3 flows into the flue gas purification mechanism 2 after passing through the bending part, and the bending part changes the direction of gas flow, which can accommodate a part of the dust in the flue gas, thereby preliminarily removing dust.

[0045] Further, the inside of the horizontal pipe 91 is detachably connected with the dust collecting box 10 along the length direction of the horizontal pipe 91, and the opening of the dust collecting box 10 faces upward. One end of the horizontal pipe 91 is provided with a mounting hole 911, which is matched with the cross-sectional shape of the dust collecting box 10, so that the dust collecting box 10 can be slid into and out of the mounting hole 911. The dust collecting box 10 can collect part of the dust in the flue gas, and after a period of work, the dust collecting box 10 can be taken out and emptied.

[0046] The inner wall of the vertical pipe 92 is further fixedly connected with a plurality of blocks 921 which are uniformly arranged in the vertical direction and staggered with each other, so that the blocks 921 can prolong the residence time of the flue gas in the vertical pipe 92 and help to enhance the preliminary dust removal effect. The blocks 921 are arranged obliquely, so that the dust adhering to the blocks 921 can easily slide down to the dust collecting box 10.

[0047] The outer wall of the horizontal pipe 91 is further fixedly connected with a vibration motor 12, so that when the vibration motor 12 is started, the horizontal pipe 91 and the vertical pipe 92 can vibrate, the blocks 921 on the inner wall of the vertical pipe 92 can vibrate, and the dust adhering to the surface of the blocks 921 can be shaken down, which helps to enhance the collection effect of the dust in the flue gas.

[0048] The working principle of the processing system for calcining industrial by-product gypsum according to the embodiment of the application is as follows: taking the working process of one of the calcining treatment kilns 3 as an example, first, the feeding valve 51 is opened, and the phosphogypsum is put into the feeding cylinder 41 through the feeding pipe 5. The rotating calcining treatment kiln 3 can drive the connecting ring 42 to rotate through the connecting rod 44, the connecting ring 42 drives the spiral push plate 43 to rotate, and the spiral push plate 43 conveys the phosphogypsum in the feeding cylinder 41 to the calcining treatment kiln 3, and then the push plate 32 in the calcining treatment kiln 3 conveys the phosphogypsum to the side away from the feeding cylinder 41. At the same time, the air inlet valve 71 is opened, and the flue gas in the smoke chamber 1 flows into the feeding cylinder 41 through the air inlet pipe 7 after the dust removal treatment in the smoke chamber 1, and then the flue gas flows into the calcining treatment kiln 3 from the feeding cylinder 41. In the calcining treatment kiln 3, the flow directions of the phosphogypsum and the flue gas are the same, so that the phosphogypsum and the high-temperature flue gas can be more fully contacted, so that the phosphogypsum is calcined and pretreated by the high-temperature flue gas, which can cool the high-temperature flue gas on the one hand and realize the pretreatment of the phosphogypsum on the other hand, so that the waste residue is converted into a useful building material.

[0049] When the flue gas in the calcining treatment kiln 3 reaches the set amount, the air inlet valve 71 is closed; when the phosphogypsum in the calcining treatment kiln 3 reaches the set amount, the feeding valve 51 is closed. After the air inlet valve 71 and the feeding valve 51 are both closed, the calcining treatment kiln 3 is still in a continuous rotating state, and the phosphogypsum is continuously turned over and transported, so that the phosphogypsum and the flue gas are further fully contacted; since the calcining treatment kiln 3 is in a closed state at this time, the effect of stewing can be achieved, and the crystal water contained in the phosphogypsum is further removed, so that a good calcining effect is achieved.

[0050] After a period of closed treatment, the discharge valve 61 is opened again, at this time the calcining treatment kiln 3 is reversely rotated, and the push plate 32 in the calcining treatment kiln 3 transports the material in the calcining treatment kiln 3 to the feeding cylinder 41, and the spiral push plate 43 in the feeding cylinder 41 transports the material in the feeding cylinder 41 to the discharge pipe 6, and then the material is discharged from the discharge pipe 6, and the calcining treatment kiln 3 is emptied, facilitating subsequent reuse. Then the exhaust valve 81 is opened, and the flue gas in the calcining treatment kiln 3 after calcining treatment is discharged into the feeding cylinder 41, and the flue gas flows into the smoke exhaust pipe 9 through the exhaust pipe 8 on the feeding cylinder 41, and then flows into the flue gas purification mechanism 2 for dust removal after preliminary dust removal in the smoke exhaust pipe 9, and the flue gas after dust removal is discharged.

[0051] When one of the calcining treatment kilns 3 needs to stop the flue gas from being introduced, the air inlet valve 71 on the next calcining treatment kiln 3 is opened, and then the air inlet valve 71 on the calcining treatment kiln 3 that stops the flue gas from being introduced is closed. Therefore, the plurality of parallel arranged calcining treatment kilns 3 enable the treatment system to accommodate the continuously generated flue gas, ensuring the continuity of the flue gas cooling and the phosphogypsum pretreatment production.

[0052] Since the calcining treatment kiln 3 is provided with only one feeding port 31, the feeding and discharging of the material are both completed through the feeding port 31, so that the sealing performance of the calcining treatment kiln 3 can be improved, thereby reducing the possibility of phosphogypsum powder leakage from the device connection after boiling.

[0053] The embodiment also discloses a treatment method, comprising the following steps: Step a. In the initial state, the three calcining treatment kilns 3 are all in a static state, and the air inlet valve 71, the exhaust valve 81, the feeding valve 51 and the discharge valve 61 on each calcining treatment kiln 3 are all in a closed state.

[0054] Step b. The first calcination treatment kiln 3 starts to rotate, driving the push plate 32 inside the first calcination treatment kiln 3 and the spiral push plate 43 inside the feeding cylinder 41 to rotate; the feeding valve 51 on the feeding cylinder 41 at the end of the first calcination treatment kiln 3 is opened, and the phosphogypsum to be treated is poured into the feeding cylinder 41 through the feeding pipe 5; after the phosphogypsum falls into the feeding cylinder 41, it is transported by the spiral push plate 43 into the first calcination treatment kiln 3, and then the push plate 32 transports the phosphogypsum to the side away from the feeding cylinder 41; the gas inlet valve 71 on the feeding cylinder 41 at the end of the first calcination treatment kiln 3 is opened, and the flue gas after dust removal in the smoke chamber 1 flows into the feeding cylinder 41 through the gas inlet pipe 7, and then flows into the first calcination treatment kiln 3; the flue gas in the first calcination treatment kiln 3 and the phosphogypsum have the same transport direction, and the phosphogypsum is pretreated by calcination through high-temperature flue gas.

[0055] Step c. When the flue gas in the first calcination treatment kiln 3 reaches the set amount, the gas inlet valve 71 on the second calcination treatment kiln 3 is opened first, and then the gas inlet valve 71 on the first calcination treatment kiln 3 is closed, so that the flue gas continuously discharged from the smoke chamber 1 can flow into the second calcination treatment kiln 3; when the phosphogypsum in the first calcination treatment kiln 3 reaches the set amount, the feeding valve 51 on the first calcination treatment kiln 3 is closed; at this time, the first calcination treatment kiln 3 is in a closed state, and the first calcination treatment kiln 3 is still in a state of continuous rotation, so that the flue gas in the first calcination treatment kiln 3 steams the phosphogypsum for a period of time, enhancing the pretreatment effect and the cooling effect of the flue gas.

[0056] Step d. After the first calcination treatment kiln 3 is closed for a period of time, the first calcination treatment kiln 3 is reversely rotated, and the discharge valve 61 and the exhaust valve 81 on the first calcination treatment kiln 3 are opened; the reversely rotating first calcination treatment kiln 3 can transport the internal materials into the feeding cylinder 41, and then discharge them from the discharge pipe 6; the flue gas after calcination in the first calcination treatment kiln 3 first flows into the feeding cylinder 41, and then is discharged to the exhaust pipe 8 and then to the flue gas purification mechanism 2 after preliminary dust removal through the exhaust pipe 9.

[0057] Step e. During the process of introducing flue gas into the second calcination treatment kiln 3, phosphogypsum is also transported into the second calcination treatment kiln 3; after the flue gas and the phosphogypsum reach the set amount, the gas inlet valve 71 on the third calcination treatment kiln 3 is opened first, and then the gas inlet valve 71 and the feeding valve 51 on the second calcination treatment kiln 3 are closed, and the second calcination treatment kiln 3 is in a closed steaming state.

[0058] Step f. After the second calcination treatment kiln 3 is closed for a period of time, the materials and flue gas in the second calcination treatment kiln 3 are discharged.

[0059] Step g. The flue gas is introduced into the third calcining treatment kiln 3, and the ardealite is fed into the third calcining treatment kiln 3 at the same time. When the flue gas and the ardealite reach the set amount, the air inlet valve 71 on the first calcining treatment kiln 3 is opened first, and then the air inlet valve 71 and the feeding valve 51 on the third calcining treatment kiln 3 are closed. The third calcining treatment kiln 3 is in a closed stewing state.

[0060] Step h. After the third calcining treatment kiln 3 is closed for a period of time, the material and the flue gas in the third calcining treatment kiln 3 are discharged.

[0061] The above is an optional embodiment of the present application, and does not limit the protection scope of the present application. Therefore, equivalent changes made according to the structure, shape, and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A system for treating gypsum produced as a by-product of calcination industry, characterized in that: include: A smoke chamber (1), the smoke chamber (1) being connected to the kiln body and being used to accommodate smoke discharged from the kiln body; A flue gas purification mechanism (2) for removing ash from the flue gas; A calcining kiln (3) is provided between a smoke chamber (1) and a smoke purification mechanism (2), wherein a plurality of calcining kilns (3) are provided and arranged in parallel, wherein the calcining kiln (3) is a rotary kiln, and a feeding port (31) for conveying phosphogypsum is provided at one end of the calcining kiln (3), so that when the calcining kiln (3) rotates in one direction, the phosphogypsum inside can be driven to move toward the end away from the feeding port (31), and when the calcining kiln (3) rotates in the other direction, the phosphogypsum inside can be driven to move toward the end away from the feeding port (31). The calcining kiln (3) moves toward one end of the feeding port (31), and an air inlet pipe (7) and an exhaust pipe (8) for conveying flue gas are provided on one side of the calcining kiln (3). The air inlet pipe (7) and the exhaust pipe (8) are both located at one end of the calcining kiln (3) near the feeding port (31). The air inlet pipe (7) is communicated with the smoke chamber (1), and the exhaust pipe (8) is communicated with the flue gas purification mechanism (2). An air inlet valve (71) is provided in the air inlet pipe (7), and an exhaust valve (81) is provided in the exhaust pipe (8); The feeding mechanism (4) is arranged outside the feeding port (31) and is used to feed the phosphogypsum into the calcining kiln (3) or discharge the phosphogypsum in the calcining kiln (3), and is capable of closing the feeding port (31).

2. A system for treating gypsum produced as a by-product of calcination according to claim 1, characterized in that: The feeding mechanism (4) includes a feeding cylinder (41), a connecting ring (42), a spiral push plate (43) and a driving member. The feeding cylinder (41) is coaxially arranged at the feeding port (31) of the calcining kiln (3). One end of the feeding cylinder (41) is closed, and the other end is connected to the inside of the calcining kiln (3) and is rotatably connected. The feeding cylinder (41) is provided with a feeding pipe (5) and a discharging pipe (6). The feeding pipe (5) is provided with a feeding valve (51). The discharging pipe (6) is provided with a feeding valve (51). 6) is provided with a discharge valve (61), the connecting ring (42) is rotatably arranged inside the feeding barrel (41), the spiral push plate (43) is fixedly connected to the connecting ring (42), one side of the spiral push plate (43) is in contact with the inner wall of the feeding barrel (41), so that when the connecting ring (42) drives the spiral push plate (43) to rotate, the material in the feeding barrel (41) can be pushed toward one end, and the driving member is provided on one side of the connecting ring (42) for driving the connecting ring (42) to rotate.

3. A system for treating gypsum produced as a by-product of calcination according to claim 2, characterized in that: The driving member is a connecting rod (44), and the connecting rod (44) is fixedly connected between the connecting ring (42) and the inner wall of the calcining kiln (3).

4. A system for treating gypsum produced as a by-product of calcination according to claim 2, characterized in that: The air inlet pipe (7) and the exhaust pipe (8) are both fixedly connected to one end of the feed barrel (41) away from the calcining kiln (3), and the air inlet pipe (7) and the exhaust pipe (8) are both communicated with the interior of the feed barrel (41).

5. A system for treating gypsum produced as a by-product of calcination according to claim 4, characterized in that: The air inlet pipe (7) and the air outlet pipe (8) are both located at the top of the feeding cylinder (41).

6. The system for treating gypsum produced as a by-product of calcination according to claim 1, wherein: A smoke exhaust pipe (9) and a fan (11) are provided between the exhaust pipe (8) and the smoke purification mechanism (2).

7. A system for treating gypsum produced as a by-product of calcination according to claim 6, characterized in that: The smoke exhaust pipe (9) is provided with a bending portion, which includes a horizontal pipe (91) and vertical pipes (92) fixedly connected to both ends of the horizontal pipe (91). The two vertical pipes (92) are both located above the horizontal pipe (91). An ash collecting box (10) is slidably and detachably connected to the interior of the horizontal pipe (91). The opening of the ash collecting box (10) faces upward, and a mounting hole (911) for the ash collecting box (10) to slide in and out is provided on the horizontal pipe (91).

8. A system for treating gypsum produced as a by-product of calcination according to claim 7, characterized in that: A stopper (921) is provided on the inner wall of the vertical tube (92). A plurality of the stoppers (921) are provided and are evenly spaced along the length direction of the vertical tube (92). The stoppers (921) are arranged in an inclined manner, and two adjacent stoppers (921) are arranged in a staggered manner.

9. A system for treating gypsum produced as a by-product of calcination according to claim 8, characterized in that: A vibration motor (12) is provided on the horizontal tube (91).

10. A method for treating gypsum produced as a by-product of calcination using the system for treating gypsum according to any one of claims 1 to 9, characterized in that: The processing method comprises the following steps: a. Open the air inlet valve (71) on the first calcining kiln (3), and the flue gas in the smoke chamber (1) enters the first calcining kiln (3) through the air inlet pipe (7) on the first calcining kiln (3). The feeding mechanism (4) feeds the phosphogypsum into the first calcining kiln (3) through the feeding port (31). The first calcining kiln (3) rotates and continuously pushes the phosphogypsum inward; b. When the flue gas in the first calcining treatment kiln (3) reaches a set amount, the air inlet valve (71) on the second calcining treatment kiln (3) is first opened, and then the air inlet valve (71) on the first calcining treatment kiln (3) is closed, and the flue gas in the smoke chamber (1) enters the second calcining treatment kiln (3), and then the phosphogypsum is fed into the second calcining treatment kiln (3) through the feeding mechanism (4); when the phosphogypsum in the first calcining treatment kiln (3) reaches a set amount, the feeding mechanism (4) stops feeding and closes the feeding port (31); c. The first calcining kiln (3) is in a closed state, and the flue gas inside calcines the phosphogypsum. During the calcination, the flue gas in the smoke chamber (1) enters the second calcining kiln (3), and the feeding mechanism (4) feeds the phosphogypsum into the second calcining kiln (3). The second calcining kiln (3) rotates and pushes the phosphogypsum inward. After the phosphogypsum in the first calcining kiln (3) is calcined for a period of time, the feeding mechanism (4) opens the feeding port (31), and the first calcining kiln (3) rotates in the opposite direction to transport the material inside outward and discharge it through the feeding port (31) and the feeding mechanism (4). The exhaust valve (81) on the first calcining kiln (3) is opened to feed the flue gas into the flue gas purification mechanism (2). d. When the flue gas in the second calcining treatment kiln (3) reaches a set amount, the air inlet valve (71) on the third calcining treatment kiln (3) is first opened, and then the air inlet valve (71) on the second calcining treatment kiln (3) is closed, and the flue gas in the smoke chamber (1) enters the third calcining treatment kiln (3), and then the phosphogypsum is fed into the third calcining treatment kiln (3) through the feeding mechanism (4); when the phosphogypsum in the second calcining treatment kiln (3) reaches a set amount, the feeding mechanism (4) stops feeding and closes the feeding port (31); e. The second calcining kiln (3) is in a closed state, and the flue gas inside calcines the phosphogypsum. After calcining for a period of time, the feeding mechanism (4) opens the feeding port (31), and the second calcining kiln (3) rotates in the opposite direction to send out the material inside. The exhaust valve (81) on the second calcining kiln (3) is opened to send the flue gas into the flue gas purification mechanism (2).

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