Magnesium sulfate production device and method

Abstract

The invention discloses a magnesium sulfate production device and method.The magnesium sulfate production device comprises a desulfurizing tower, a flue gas outlet is formed in the top of the desulfurizing tower, and a flue gas inlet is formed in the side edge of the desulfurizing tower; a demister, a third-stage SO2 absorption spraying layer, a second-stage SO2 absorption spraying layer, a liquid accumulator, an evaporation concentration spraying layer and an emergency cooling layer are sequentially arranged at the inner top of the desulfurizing tower from top to bottom, a circulating settling tank is arranged in the inner middle of the desulfurizing tower, an overflow port is formed in the circulating settling tank, and the overflow port passes through a second filter. The magnesium sulfate production device and method have the beneficial effects that the evaporation concentration section and the absorption section are isolated through the slurry collection section, so that desulfurization slurry forms more than three cycles with functional division, the byproduct magnesium sulfate is crystallized in the desulfurization tower, a large amount of steam does not need to be consumed for concentration and crystallization in a post-treatment process, and the production efficiency is improved. Therefore, on the premise of ensuring the normal desulfurization efficiency, the investment is saved, and the desulfurization operation cost is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of magnesium sulfate production, and in particular to a magnesium sulfate production device and method. Background Art

[0002] The magnesium oxide flue gas desulfurization technology has been gradually promoted and applied, with the market share increasing from less than 1% in 2005 to more than 6% at present. The wet magnesium oxide desulfurization technology has been recognized by more and more people. The use of magnesium oxide desulfurization process and the preparation of magnesium sulfate by-product from desulfurization waste liquid not only solves the problem of desulfurization gypsum treatment generated by traditional calcium desulfurization, but also can offset part of the operation and maintenance costs of the desulfurization device through the sales of magnesium sulfate by-products. It has greater market application advantages than the traditional calcium method from both technical and economic perspectives.

[0003] Since the traditional magnesium oxide method for producing magnesium sulfate from desulfurization waste liquid uses steam as a medium for evaporation, crystallization, and drying, the method for producing magnesium sulfate using desulfurization waste liquid requires more steam consumption, which directly increases the desulfurization operation cost. For example, CN1733656A discloses a method for preparing magnesium sulfate heptahydrate fertilizer using boiler flue gas, wherein the magnesium sulfate solution is concentrated and crystallized using the characteristic that the solubility of magnesium sulfate decreases when the temperature exceeds 60°C. This high-temperature crystallization method requires more high-quality steam consumption, and will cause frequent blockage of the slurry delivery pipeline, making it difficult to achieve continuous and stable production of by-products. CN102745726A discloses a method for producing magnesium sulfate heptahydrate using desulfurization waste liquid, and the crystallization method used is "sending the obtained liquid into an evaporator, discharging the slurry after concentration, the evaporation temperature is 100-130°C, and the discharged slurry is cooled and crystallized at a temperature of 30-45°C to obtain magnesium sulfate heptahydrate". This evaporation and crystallization method requires high steam quality, and if low-grade steam is used, the consumption increases. Regardless of which of the above two methods is used, the production of one ton of magnesium sulfate requires about 1.2 to 2 tons of steam. The steam price is calculated at 80 yuan / ton, and the steam consumption cost of one ton of magnesium sulfate is about 160 yuan. Although the comprehensive cost of magnesium desulfurization is lower than that of calcium desulfurization, the current magnesium desulfurization tower outside the use of three-effect evaporation and other processes to produce magnesium sulfate still wastes steam resources, and the desulfurization operation cost is still high. In addition, the existing magnesium sulfate production equipment cannot be dried after production, the drying is uneven, and the drying effect is poor. At the same time, after drying, it needs to be cooled before entering the packaging process. Conventional cooling treatment takes a long time, which is not conducive to production line production.

[0004] Currently, no effective solution has been proposed for the problems in the related technologies. Summary of the invention

[0005] In view of the problems in the related art, the present invention provides a magnesium sulfate production device and method to overcome the above technical problems existing in the existing related technology.

[0006] To this end, the specific technical solution adopted by the present invention is as follows: A magnesium sulfate production device comprises a desulfurization tower, wherein a flue gas outlet is arranged at the top of the desulfurization tower, a flue gas inlet is arranged at the side of the desulfurization tower, a demister, a three-stage SO2 absorption spray layer, a two-stage SO2 absorption spray layer, a liquid accumulator, an evaporation concentration spray layer and an emergency cooling layer are arranged in sequence at the inner top of the desulfurization tower from top to bottom, a circulating sedimentation tank is arranged at the inner middle part of the desulfurization tower, an overflow port is arranged on the circulating sedimentation tank, the overflow port is connected to the evaporation concentration spray layer through a second filter and an evaporation concentration circulation pump, a discharge port is arranged at the lower part of the circulating sedimentation tank, the discharge port is connected to a crystallization tank outside the desulfurization tower, one side of the crystallization tank is connected to a centrifuge, the centrifuge is connected to a drying cooler, and the One side of the dry cooler is connected to the packaging machine, the inner bottom of the desulfurization tower is divided into a slurry circulation pool and an evaporation and concentration slurry pool by a partition, the liquid accumulator is connected to the slurry circulation pool, the secondary SO2 absorption spray layer and the tertiary SO2 absorption spray layer are connected to the slurry circulation pool through the secondary SO2 absorption circulation pump and the tertiary SO2 absorption circulation pump respectively, the output end of the slurry circulation pool is connected to one end of the first filter through the slurry pool discharge pump, the other end of the first filter is connected to the evaporation and concentration slurry pool, the output end of the centrifuge is connected to the evaporation and concentration spray layer through the mother liquor reflux evaporation and concentration circulation pump, and the emergency cooling layer is connected to the slurry circulation pool through the emergency cooling layer pump.

[0007] Preferably, the drying cooler includes a drying mechanism and a cooling mechanism, the drying mechanism includes a drying box, a drying chamber is provided inside the drying box, a box door is provided on the drying box, a plurality of heating plates are provided inside the drying chamber, the ends of the heating plates extend to the outside of the drying box, a hot air blower is provided in the inner wall of the drying chamber, the input end of the hot air blower extends to the outside of the drying box, the output end of the hot air blower is connected to an annular air duct, a plurality of vertical hot air ducts are evenly connected to the top of the annular air duct, and a plurality of hot air heads connected to the vertical hot air ducts are provided on the inner wall of the drying chamber.

[0008] Preferably, the drying mechanism also includes a driving chamber opened below the drying chamber, a driving motor is fixed on one side of the inner bottom of the driving chamber, a driving gear is connected to the top output end of the driving motor, a rotating column is rotatably connected between the drying chamber and the driving chamber, the bottom end of the rotating column penetrates into the interior of the driving chamber and an outer gear ring meshing with the driving gear is fixed on the outer surface, an inner chamber is opened inside the rotating column, a fixing rod is provided in the inner middle part of the inner chamber, a bottom end of the fixing rod penetrates through the rotating column and extends into the driving chamber and is connected and fixed to the inner wall of the driving chamber, a plurality of fixed bevel gears are evenly fixed on one end of the fixing rod inside the inner chamber, a plurality of rotating rods are rotatably connected to the circumferential outer surface of the rotating column, one end of the rotating rod penetrates into the interior of the inner chamber and is connected and fixed to the driven bevel gear, the driven bevel gear is meshed with the fixed bevel gear, the other end of the rotating rod penetrates through the outer side of the rotating column and a plurality of turning blades are fixed on the outer surface.

[0009] Preferably, the drying mechanism also includes a material rack connected and fixed to the drying chamber via a fixed plate, a material trough is provided on the top of the material rack, a rotating hole matching the rotating column is provided in the middle of the material trough, and a protective ring matching the rotating hole is provided in the middle of the material trough.

[0010] Preferably, a through hole cooperating with the fixing rod is provided on the rotating column, two ends of the through hole are respectively connected with the inner cavity and the outer surface of the rotating column, and a wind cutting ring is fixed to the circumferential outer surface of the material rack.

[0011] Preferably, the cooling mechanism includes a shell, a discharge barrel is provided on the top of the shell, the bottom of the discharge barrel is communicated with the shell, a plurality of storage barrels are placed in sequence from top to bottom inside the discharge barrel, a discharge port is provided at the bottom of the shell, an electric door is provided in the discharge port, a conveyor belt matching the discharge port is provided at the bottom of the shell, a rotating motor is fixed at the bottom center of the shell, the top output end of the rotating motor passes through the shell and is connected and fixed to a rotating disk, a plurality of placement grooves are provided on the circumferential outer surface of the rotating disk, the storage barrel falls into the placement groove by passing through the discharge barrel, a water cavity matching the plurality of placement grooves is provided inside the rotating disk, and a water inlet hole connected to the water cavity is provided at the top of the rotating disk.

[0012] Preferably, the cooling mechanism also includes a condensing water tank and a water pump fixed on the top of the shell, the condensing water tank is connected to the input end of the water pump, the output end of the water pump is connected to a water supply ring pipe, the bottom of the water supply ring pipe is connected to a plurality of cooling water pipes, the cooling water pipe passes through the inner wall of the shell, the bottom end of the cooling water pipe passes through the bottom of the shell and is connected to the return water ring pipe, one side of the return water ring pipe is connected to the return water pipe, and the end of the return water pipe is connected to the condensing water tank.

[0013] Preferably, a cooling fan is also provided on one side of the top of the shell, and the output end of the cooling fan is hung to the inner top of the shell to be connected with a plurality of cooling heads, and the cooling heads cooperate with the placement slots.

[0014] Preferably, a maintenance door cooperating with the rotating disk is provided on the side of the shell.

[0015] According to another aspect of the present invention, there is provided a method for producing magnesium sulfate, which is used in a magnesium sulfate production device and comprises the following steps: The flue gas enters the desulfurization tower from the flue gas inlet, enters the evaporation concentration spray layer after passing through the emergency cooling layer, enters the secondary SO2 absorption spray layer and the tertiary SO2 absorption spray layer in turn for desulfurization absorption reaction after cooling and initial absorption, and finally enters the demister for dehydration and demisting before being directly discharged through the top chimney flue gas outlet; The mixed liquid after absorbing sulfur dioxide from the secondary SO2 absorption spray layer and the tertiary SO2 absorption spray layer enters the slurry circulation pool through the liquid accumulator; The absorption liquid pumped out by the slurry circulation pool pump is discharged into the first filter through the slurry pool discharge pump, and then enters the evaporation concentration slurry pool after filtration, and is pumped into the evaporation concentration spray layer by the evaporation concentration circulation pump for circulation evaporation concentration; The absorption liquid overflowing from the overflow port of the circulating sedimentation tank is filtered through the second filter to form a filtered clear liquid, and the filtered clear liquid is pumped into the evaporation and concentration spray layer through the evaporation and concentration circulation pump for recycling and crystallization; Discharging a solid-liquid mixture containing magnesium sulfate crystals with a solid content of greater than 30 wt% and a particle size greater than 0.1 mm from a discharge port at the bottom of the circulating sedimentation tank, sending the solid-liquid mixture into a crystallization tank, and further forming magnesium sulfate crystals with a particle size greater than 0.2 mm in the crystallization tank by cooling to prevent crystal sedimentation; The solid-liquid mixture entering the crystallization tank from the circulating sedimentation tank is separated in the crystallization tank, and the mother liquor returns to the evaporation and concentration spray layer for further circulation crystallization. The crystal slurry with a solid content greater than 40wt% is sent to the centrifuge for separation, and the mother liquor in the centrifuge returns to the evaporation and concentration spray layer. The dry cooler with a water content less than 2wt% is further dried to a finished product and sent to a packaging machine.

[0016] The beneficial effects of the present invention are: 1. The magnesium sulfate production device and method of the present invention isolates the evaporation concentration section and the absorption section through the slurry collection section, so that the desulfurization slurry forms a three-fold or more cycle with functional distinction, and realizes the crystallization of the byproduct magnesium sulfate in the desulfurization tower, without consuming a large amount of steam for concentration and crystallization in the post-processing process, thereby saving investment and greatly reducing the desulfurization operation cost under the premise of ensuring normal desulfurization efficiency; 2. The present invention adopts the design of the drying mechanism, so that the magnesium sulfate crystals are placed in the material troughs on several material racks, and then the driving motor is started, the driving motor drives the driving gear to rotate, the driving gear drives the rotating column to rotate horizontally through the outer gear ring, the rotating column drives several rotating rods to rotate horizontally while rotating, the rotating rods rotate horizontally and drive the driven bevel gears to rotate horizontally, the driven bevel gears rotate horizontally while rotating along the fixed bevel gears, the driven bevel gears move on the fixed bevel gears and drive several material turning blades to rotate vertically, so that several material turning blades can rotate horizontally along the material trough while performing vertical rotation, so as to realize the uniform turning action of the material trough, at the same time, the hot air blower transports the hot air to several hot air heads inside the drying chamber through the annular air duct and the vertical hot air duct, so as to dry the inside of the drying chamber; 3. The present invention places the dried high-temperature material in several storage barrels, and places several storage barrels with high-temperature materials into the lower barrel from top to bottom in turn. When the placement slot on the rotating disk is aligned with the lower barrel, the storage barrel will enter into several placement slots in turn, thereby facilitating the storage barrel to enter the shell for cooling treatment. At the same time, the water pump transports the low-temperature water in the condensation water tank to several cooling water pipes. The low-temperature water entering the cooling water pipes will take away the heat in the inner wall of the shell, thereby achieving a low-temperature environment. The low-temperature water after heat exchange will be transported back to the condensation water tank through the return pipe. Synchronously, the air cooler transports the low-temperature airflow through several cold air heads to the inside of the shell for low-temperature treatment of the material. When the storage barrel after low-temperature cooling rotates and moves to above the electric door, the electric door opens, and the storage barrel falls onto the conveyor belt and is transported to the baler. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is a schematic diagram of the overall structure of a magnesium sulfate production device according to an embodiment of the present invention; Figure 22 is a schematic diagram of the structure of a drying box for a magnesium sulfate production device according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the internal structure of a drying box of a magnesium sulfate production device according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the connection structure of a material rack, a protective ring, and an air cutting ring of a magnesium sulfate production device according to an embodiment of the present invention; Figure 5 This is a schematic diagram of a cross-sectional structure of a material rack of a magnesium sulfate production device according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the cooling mechanism structure of a magnesium sulfate production device according to an embodiment of the present invention; Figure 7 This is a schematic diagram of a cross-sectional structure of a shell of a magnesium sulfate production device in a bottom-up state according to an embodiment of the present invention; Figure 8 It is a schematic diagram of a cross-sectional structure of a shell of a magnesium sulfate production device in a top view according to an embodiment of the present invention; Fig. 9 Schematic diagram of the cross-sectional structure of a shell of a magnesium sulfate production device according to an embodiment of the present invention Figure 1 ; Fig.10 Schematic diagram of the cross-sectional structure of a shell of a magnesium sulfate production device according to an embodiment of the present invention Figure 2 ; Fig.11 The present invention is a flowchart of a method for producing magnesium sulfate according to an embodiment of the present invention.

[0019] In the figure: 1. Desulfurization tower; 2. Circulation sedimentation tank; 3. Evaporation and concentration spray layer; 4. Liquid accumulator; 5. Overflow port; 6. Discharge port; 7. Secondary SO2 absorption spray layer; 8. Third-level SO2 absorption spray layer; 9. Demister; 10. Flue gas outlet; 11. Slurry circulation pool; 12. Evaporation and concentration circulation pump; 13. Secondary SO2 absorption circulation pump; 14. Third-level SO2 absorption circulation pump; 15. Emergency cooling layer pump; 16. Crystallization tank; 17. Centrifuge; 18. Drying cooler; 19. Packaging machine; 20. Mother liquor reflux evaporation and concentration circulation pump; 21. Slurry pool discharge pump; 22. First filter; 23. Flue gas inlet; 24. Emergency cooling layer; 25. Second filter; 26. Evaporation and concentration slurry pool; 27. Return pipe; 28. Drying box; 29. ​​Box door; 30. Drying chamber; 3 1. Heating plate; 32. Hot air blower; 33. Annular air duct; 34. Vertical hot air duct; 35. Hot air head; 36. Driving cavity; 37. Driving motor; 38. Driving gear; 39. Rotating column; 40. External gear ring; 41. Inner cavity; 42. Fixed rod; 43. Fixed bevel gear; 44. Driven bevel gear; 45. Rotating rod; 46. Turning blade; 47. Material rack; 48. Material trough; 49. Rotating hole; 50. Protective ring; 51. Cutting air ring; 52. Fixed plate; 53. Shell; 54. Unloading barrel; 55. Electric door; 56. Conveyor belt; 57. Condensate tank; 58. Water pump; 59. Water supply ring pipe; 60. Cooling water pipe; 61. Air cooler; 62. Cold air head; 63. Rotating disk; 64. Placement slot; 65. Water cavity; 66. Water inlet hole; 67. Storage barrel. DETAILED DESCRIPTION

[0020] To further illustrate each embodiment, the present invention provides drawings, which are part of the disclosure of the present invention and are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, ordinary technicians in the field should be able to understand other possible implementations and advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0021] According to an embodiment of the present invention, a magnesium sulfate production device is provided.

[0022] Embodiment 1; like Figure 1-10As shown, the magnesium sulfate production device according to the embodiment of the present invention includes a desulfurization tower 1, the top of the desulfurization tower 1 is provided with a flue gas outlet 10, the side of the desulfurization tower 1 is provided with a flue gas inlet 23, the inner top of the desulfurization tower 1 is provided with a demister 9, a three-stage SO2 absorption spray layer 8, a two-stage SO2 absorption spray layer 7, a liquid accumulator 4, an evaporation concentration spray layer 3 and an emergency cooling layer 24 from top to bottom, a circulating sedimentation tank 2 is provided in the middle of the inner part of the desulfurization tower 1, an overflow port 5 is provided on the circulating sedimentation tank 2, and the overflow port 5 is connected to the evaporation concentration spray layer 3 through a second filter 25 and an evaporation concentration circulation pump 12, a discharge port 6 is provided at the lower part of the circulating sedimentation tank 2, and the discharge port 6 is connected to the crystallization tank 16 outside the desulfurization tower 1, and a stirring device is provided in the crystallization tank 16, and the stirring device can adopt an air stirring device or an electric stirring device, etc., and one side of the crystallization tank 16 is connected to a centrifuge 17. The centrifuge 17 is connected to the dry cooler 18, one side of the dry cooler 18 is connected to the packaging machine 19, the inner bottom of the desulfurization tower 1 is divided into a slurry circulation pool 11 and an evaporation concentration slurry pool 26 by a partition, the liquid accumulator 4 is connected to the slurry circulation pool 11, the secondary SO2 absorption spray layer 7 and the tertiary SO2 absorption spray layer 8 are connected to the slurry circulation pool 11 through the secondary SO2 absorption circulation pump 13 and the tertiary SO2 absorption circulation pump 14 respectively, the output end of the slurry circulation pool 11 is connected to one end of the first filter 22 through the slurry pool discharge pump 21, and the other end of the first filter 22 is connected to the evaporation concentration slurry pool 26, the output end of the centrifuge 17 is connected to the evaporation concentration spray layer 3 through the mother liquor reflux evaporation concentration circulation pump 20, and the emergency cooling layer 24 is connected to the slurry circulation pool 11 through the emergency cooling layer pump 15.

[0023] Embodiment 2: like Figure 1-10As shown, the drying cooler 18 includes a drying mechanism and a cooling mechanism. The drying mechanism includes a drying box 28. A drying chamber 30 is provided inside the drying box 28. A door 29 is provided on the drying box 28. A plurality of heating plates 31 are provided inside the drying chamber 30. The ends of the heating plates 31 extend through the outside of the drying box 28. A hot air blower 32 is provided in the inner wall of the drying chamber 30. The input end of the hot air blower 32 extends through the outside of the drying box 28. The output end of the hot air blower 32 is connected to an annular air duct 33. The top of the annular air duct 33 is evenly connected to a plurality of vertical hot air ducts 34. The inner wall of the drying chamber 30 is provided with a plurality of hot air heads 35 connected with the vertical hot air pipe 34. The drying mechanism also includes a driving chamber 36 opened below the drying chamber 30. A driving motor 37 is fixed to one side of the inner bottom of the driving chamber 36. A driving gear 38 is connected to the top output end of the driving motor 37. A rotating column 39 is rotatably connected between the drying chamber 30 and the driving chamber 36. The bottom end of the rotating column 39 passes through the interior of the driving chamber 36 and an outer gear ring 40 meshing with the driving gear 38 is fixed to the outer surface. An inner cavity 41 is opened inside the rotating column 39. The inner cavity A fixed rod 42 is provided in the middle of the inner part of 41, and the bottom end of the fixed rod 42 passes through the rotating column 39 and extends to the inside of the driving cavity 36 and is connected and fixed to the inner wall of the driving cavity 36. A plurality of fixed bevel gears 43 are evenly fixed to one end of the fixed rod 42 in the inner cavity 41, and a plurality of rotating rods 44 are rotatably connected to the outer surface of the circumference of the rotating column 39. One end of the rotating rod 44 passes through the inner cavity 41 and is connected and fixed to the driven bevel gear 45, and the driven bevel gear 45 is meshed with the fixed bevel gear 43. The other end of the rotating rod 45 passes through the outer side of the rotating column 39 A plurality of material turning blades 46 are fixed on the outer surface, the drying mechanism also includes a material rack 47 connected and fixed to the drying chamber 30 through a fixing plate 52, a material trough 48 is provided on the top of the material rack 47, a rotating hole 49 matching the rotating column 39 is provided in the middle of the material trough 48, a protective ring 50 matching the rotating hole 49 is provided in the middle of the material trough 48, a through hole matching the fixing rod 42 is provided on the rotating column 39, both ends of the through hole are respectively connected to the inner cavity 41 and the outer surface of the rotating column 39, and a wind cutting ring 51 is fixed to the circumferential outer surface of the material rack 47;Through the design of the drying mechanism, after the magnesium sulfate crystals are placed in the material troughs 48 on the several material racks 47, the driving motor 37 is started, the driving motor 37 drives the driving gear 38 to rotate, the driving gear 38 drives the rotating column 39 to rotate horizontally through the outer gear ring 40, and the rotating column 39 rotates while driving the several rotating rods 44 to rotate horizontally, and the rotating rods 44 rotate horizontally to drive the driven bevel gear 45 to rotate horizontally, and the driven bevel gear 45 rotates horizontally while rotating along the fixed bevel gear 43, and the driven bevel gear 45 moves on the fixed bevel gear 43 and drives the several material turning blades 46 to rotate vertically, so that the several material turning blades 46 rotate horizontally along the material trough 48 and also perform vertical rotation, so as to realize the uniform material turning action of the material trough 48, and at the same time, the hot air blower 32 conveys the hot air to the several hot air heads 35 inside the drying chamber 30 through the annular air duct 33 and the vertical hot air duct 34, so as to dry the inside of the drying chamber 30. ;

[0024] Embodiment three; like Figure 1-10As shown, the cooling mechanism includes a shell 53, a discharge barrel 54 is provided on the top of the shell 53, the bottom of the discharge barrel 54 is connected to the shell 53, a plurality of storage barrels 67 are placed in sequence from top to bottom in the discharge barrel 54, a discharge port is provided at the bottom of the shell 53, an electric door 55 is provided in the discharge port, a conveyor belt 56 matching the discharge port is provided at the bottom of the shell 53, a rotating motor is fixed at the bottom center of the shell 53, the top output end of the rotating motor passes through the shell 53 and is connected and fixed to the rotating disk 63, a plurality of placement grooves 64 are provided on the circumferential outer surface of the rotating disk 63, and the storage barrel 67 passes through the discharge barrel 54. The cylinder 54 falls into the placement groove 64, and the interior of the rotating disk 63 is provided with a water cavity 65 that matches with the plurality of placement grooves 64. The top of the rotating disk 63 is provided with a water inlet hole 66 that is connected with the water cavity 65. The cooling mechanism also includes a condensation water tank 57 and a water pump 58 fixed on the top of the shell 53. The condensation water tank 57 is connected with the input end of the water pump 58, and the output end of the water pump 58 is connected with a water delivery ring pipe 59. The bottom of the water delivery ring pipe 59 is connected with a plurality of cooling water pipes 60. The cooling water pipe 60 penetrates into the inner wall of the shell 53, and the bottom end of the cooling water pipe 60 penetrates to the bottom of the shell 53 and is connected with the return water ring pipe. One side of the return water ring pipe is connected to the return water pipe 27, and the end of the return water pipe 57 is connected to the condensation water tank 27. A cold air fan 61 is also provided on one side of the top of the shell 53. The output end of the cold air fan 61 is hung to the inner top of the shell 53 and connected to a plurality of cold air heads 62. The cold air heads 62 and the placement grooves 64 cooperate with each other. A maintenance door that cooperates with the rotating disk 63 is provided on the side of the shell 53; the dried high-temperature materials are placed in a plurality of storage barrels 67, and a plurality of storage barrels 67 with high-temperature materials are placed in the lower barrel 54 from top to bottom in turn. When the placement grooves 64 on the rotating disk 63 are aligned with the lower barrel 54, the storage barrels 67 will enter into the rods in turn. The material storage barrel 67 is placed in a placement groove 64, thereby facilitating the material storage barrel 67 to enter the shell 53 for cooling treatment. At the same time, the water pump 58 transports the low-temperature water in the condensation water tank 57 to a number of cooling water pipes 60. The low-temperature water entering the cooling water pipes 60 will take away the heat in the inner wall of the shell 53, thereby achieving a low-temperature environment. The low-temperature water after heat exchange will be transported back to the condensation water tank 57 through the return pipe 27. Synchronously, the air cooler 61 transports the low-temperature airflow through a number of cold air heads 62 to the inside of the shell 53 for low-temperature treatment of the material. When the material storage barrel 67 after low-temperature cooling rotates and moves above the electric door 55, the electric door 55 opens, and the material storage barrel 67 falls onto the conveyor belt 56 and is transported to the baler 19.

[0025] Embodiment 4: like Figure 1-11As shown, according to an embodiment of the present invention, a method for producing magnesium sulfate is also provided, which is used in a magnesium sulfate production device and comprises the following steps: Step S101, flue gas enters the desulfurization tower 1 from the flue gas inlet 23 of the desulfurization tower 1, enters the evaporation concentration spray layer 3 after passing through the emergency cooling layer 24, enters the secondary SO2 absorption spray layer 7 and the tertiary SO2 absorption spray layer 8 in turn after cooling and preliminary absorption for desulfurization absorption reaction, and finally enters the demister 9 for dehydration and demisting before being directly discharged through the top chimney flue gas outlet 10; Step S103, the mixed liquid after absorbing sulfur dioxide from the secondary SO2 absorption spray layer 7 and the tertiary SO2 absorption spray layer 8 enters the slurry circulation pool 11 through the liquid accumulator 4; Step S105, the absorbent pumped out by the slurry circulation pool 11 is discharged into the first filter 22 through the slurry pool discharge pump 21, enters the evaporation concentration slurry pool 26 after filtration, and is pumped into the evaporation concentration spray layer 3 by the evaporation concentration circulation pump 12 for circulation evaporation concentration; Step S107, the absorption liquid overflowing from the overflow port 5 of the circulating sedimentation tank 2 is filtered through the second filter 25 to form a filtered clear liquid, and the filtered clear liquid is pumped into the evaporation concentration spray layer 3 through the evaporation concentration circulation pump 12 for recycling and crystallization. Step S109, discharging a solid-liquid mixture having a solid content greater than 30 wt% and containing magnesium sulfate crystals having a particle size greater than 0.1 mm from the bottom discharge port 6 of the circulating sedimentation tank 2, and sending the solid-liquid mixture into a crystallization tank 16, where the crystals are cooled to further form magnesium sulfate crystals having a particle size greater than 0.2 mm to prevent crystal sedimentation; Step S111, the solid-liquid mixture entering the crystallization tank 16 from the circulating sedimentation tank 2 is separated in the crystallization tank 16, the mother liquor returns to the evaporation concentration spray layer 3 for further circulation crystallization, the slurry with a solid content greater than 40wt% is sent to the centrifuge 17 for separation, the mother liquor in the centrifuge returns to the evaporation concentration spray layer 3, and the dry cooler 18 with a water content less than 2wt% is further dried to a finished product and sent to the packaging machine 19.

[0026] In summary, through the design of the drying mechanism, the magnesium sulfate crystals are placed in the material troughs 48 on the several material racks 47, and then the driving motor 37 is started, the driving motor 37 drives the driving gear 38 to rotate, and the driving gear 38 drives the rotating column 39 to rotate horizontally through the outer gear ring 40. The rotating column 39 rotates while driving the several rotating rods 44 to rotate horizontally. The rotating rods 44 rotate horizontally and drive the driven bevel gears 45 to rotate horizontally. The driven bevel gears 45 rotate horizontally while rotating along the fixed bevel gear 43. The driven bevel gears 45 will move on the fixed bevel gears 43 and drive the several material turning blades 46 to rotate vertically, so that the several material turning blades 46 can rotate horizontally along the material trough 48 while also performing vertical rotation, thereby realizing a uniform material turning action on the material trough 48. At the same time, the hot air blower 32 transports the hot air through the annular air duct 33 and the vertical hot air duct 34 to the several hot air heads 35 inside the drying chamber 30, thereby performing a drying action on the inside of the drying chamber 30. The dried high-temperature material is placed in a plurality of storage barrels 67, and a plurality of storage barrels 67 with high-temperature materials are placed in the lower barrel 54 from top to bottom in sequence. When the placement slots 64 on the rotating disk 63 are aligned with the lower barrel 54, the storage barrels 67 will enter into the plurality of placement slots 64 in sequence, thereby facilitating the storage barrels 67 to enter the shell 53 for cooling treatment. At the same time, the water pump 58 transports the low-temperature water in the condensation water tank 57 to a plurality of cooling water pipes 60. The low-temperature water entering the cooling water pipes 60 will take away the heat in the inner wall of the shell 53, thereby achieving a low-temperature environment. The low-temperature water after heat exchange will be transported back to the condensation water tank 57 through the return pipe 27. Synchronously, the air cooler 61 transports the low-temperature airflow through a plurality of cold air heads 62 to the inside of the shell 53 for low-temperature treatment of the material. When the low-temperature cooled storage barrel 67 rotates and moves above the electric door 55, the electric door 55 opens, and the storage barrel 67 falls onto the conveyor belt 56 and is transported to the baler 19.

[0027] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A magnesium sulfate production device, characterized in that, The invention comprises a desulfurization tower (1), wherein the top of the desulfurization tower (1) is provided with a flue gas outlet (10), the side of the desulfurization tower (1) is provided with a flue gas inlet (23), the inner top of the desulfurization tower (1) is provided with a demister (9), a third-stage SO2 absorption spray layer (8), a second-stage SO2 absorption spray layer (7), a liquid accumulator (4), an evaporation concentration spray layer (3) and an emergency cooling layer (24) in order from top to bottom, and the inner middle part of the desulfurization tower (1) is provided with a circulating sedimentation tank (2), the circulating An overflow port (5) is provided on the circular sedimentation tank (2), and the overflow port (5) is connected to the evaporation concentration spray layer (3) via a second filter (25) and an evaporation concentration circulation pump (12). A discharge port (6) is provided at the lower part of the circulation sedimentation tank (2), and the discharge port (6) is connected to a crystallization tank (16) outside the desulfurization tower (1). One side of the crystallization tank (16) is connected to a centrifuge (17), and the centrifuge (17) is connected to a drying cooler (18). One side of the drying cooler (18) is connected to the packaging machine (19), the inner bottom of the desulfurization tower (1) is divided into a slurry circulation pool (11) and an evaporation concentration slurry pool (26) by a partition, the liquid accumulator (4) is connected to the slurry circulation pool (11), and the secondary SO2 absorption spray layer (7) and the tertiary SO2 absorption spray layer (8) are connected to the slurry circulation pool (11) through a secondary SO2 absorption circulation pump (13) and a tertiary SO2 absorption circulation pump (14) respectively. The output end of the slurry circulation pool (11) is connected to one end of the first filter (22) through the slurry pool discharge pump (21), and the other end of the first filter (22) is connected to the evaporation and concentration slurry pool (26). The output end of the centrifuge (17) is connected to the evaporation and concentration spray layer (3) through the mother liquor reflux evaporation and concentration circulation pump (20), and the emergency cooling layer (24) is connected to the slurry circulation pool (11) through the emergency cooling layer pump (15).

2. A magnesium sulfate production device according to claim 1, characterized in that, The drying cooler (18) comprises a drying mechanism and a cooling mechanism. The drying mechanism comprises a drying box (28). A drying chamber (30) is provided inside the drying box (28). A box door (29) is provided on the drying box (28). A plurality of heating plates (31) are provided inside the drying chamber (30). The ends of the heating plates (31) extend through the outside of the drying box (28). A hot air blower (32) is provided in the inner wall of the drying chamber (30). The input end of the hot air blower (32) extends through the outside of the drying box (28). The output end of the hot air blower (32) is connected to an annular air duct (33). The top of the annular air duct (33) is evenly connected to a plurality of vertical hot air ducts (34). A plurality of hot air heads (35) connected to the vertical hot air ducts (34) are provided on the inner wall of the drying chamber (30).

3. A magnesium sulfate production device according to claim 2, characterized in that, The drying mechanism further comprises a driving chamber (36) provided below the drying chamber (30); a driving motor (37) is fixed to one side of the inner bottom of the driving chamber (36); a driving gear (38) is connected to the top output end of the driving motor (37); a rotating column (39) is rotatably connected between the drying chamber (30) and the driving chamber (36); the bottom end of the rotating column (39) penetrates into the interior of the driving chamber (36) and an outer toothed ring (40) meshing with the driving gear (38) is fixed to the outer surface; an inner chamber (41) is provided inside the rotating column (39); a fixing rod (42) is provided in the middle of the inner chamber (41); the bottom of the fixing rod (42) is connected to the inner chamber (41); One end of the rotating rod (44) passes through the rotating column (39) and extends to the interior of the driving chamber (36) and is connected and fixed to the inner wall of the driving chamber (36); a plurality of fixed bevel gears (43) are evenly fixed to one end of the fixed rod (42) inside the inner chamber (41); a plurality of rotating rods (44) are rotatably connected to the circumferential outer surface of the rotating column (39); one end of the rotating rod (44) passes through the interior of the inner chamber (41) and is connected and fixed to a driven bevel gear (45); the driven bevel gear (45) is meshed with the fixed bevel gear (43); the other end of the rotating rod (45) passes through the outer side of the rotating column (39) and a plurality of material turning blades (46) are fixed to the outer surface.

4. A magnesium sulfate production device according to claim 3, characterized in that, The drying mechanism further comprises a material rack (47) connected and fixed to the drying chamber (30) via a fixing plate (52); a material trough (48) is provided at the top of the material rack (47); a rotating hole (49) cooperating with the rotating column (39) is provided at the middle of the material trough (48); and a protective ring (50) cooperating with the rotating hole (49) is provided at the middle of the material trough (48).

5. A magnesium sulfate production device according to claim 4, characterized in that, The rotating column (39) is provided with a through hole that matches the fixing rod (42), and the two ends of the through hole are respectively connected to the inner cavity (41) and the outer surface of the rotating column (39), and a wind cutting ring (51) is fixed to the circumferential outer surface of the material rack (47).

6. A magnesium sulfate production device according to claim 4, characterized in that, The cooling mechanism comprises a shell (53), a discharge barrel (54) is provided at the top of the shell (53), the bottom of the discharge barrel (54) is communicated with the shell (53), a plurality of material storage barrels (67) are placed in sequence from top to bottom inside the discharge barrel (54), a discharge port is provided at the bottom of the shell (53), an electric door (55) is provided in the discharge port, a conveyor belt (56) matched with the discharge port is provided at the bottom of the shell (53), and a rotating motor is fixed at the center of the bottom of the shell (53), The top output end of the rotating motor passes through the interior of the housing (53) and is connected and fixed to the rotating disk (63); a plurality of placement grooves (64) are provided on the circumferential outer surface of the rotating disk (63); the material storage barrel (67) falls into the placement grooves (64) through the lower barrel (54); a water cavity (65) matching the plurality of placement grooves (64) is provided inside the rotating disk (63); and a water inlet hole (66) communicating with the water cavity (65) is provided on the top of the rotating disk (63).

7. A magnesium sulfate production device according to claim 6, characterized in that, The cooling mechanism further comprises a condensing water tank (57) and a water pump (58) fixed on the top of the shell (53); the condensing water tank (57) is connected to the input end of the water pump (58); the output end of the water pump (58) is connected to a water supply ring pipe (59); the bottom of the water supply ring pipe (59) is connected to a plurality of cooling water pipes (60); the cooling water pipe (60) penetrates into the inner wall of the shell (53); the bottom end of the cooling water pipe (60) penetrates to the bottom of the shell (53) and is connected to the return water ring pipe; one side of the return water ring pipe is connected to the return water pipe (27); the end of the return water pipe (57) is connected to the condensing water tank (27).

8. A magnesium sulfate production device according to claim 7, characterized in that, A cooling fan (61) is also provided on one side of the top of the shell (53), and the output end of the cooling fan (61) is connected to the inner top of the shell (53) to communicate with a plurality of cooling heads (62), and the cooling heads (62) cooperate with the placement slots (64).

9. A magnesium sulfate production device according to claim 8, characterized in that, A maintenance door matching the rotating disk (63) is provided on the side of the housing (53).

10. A method for producing magnesium sulfate, characterized in that: The magnesium sulfate production device according to claim 9 comprises the following steps: The flue gas enters the desulfurization tower (1) from the flue gas inlet (23) of the desulfurization tower (1), passes through the emergency cooling layer (24) and then enters the evaporation concentration spray layer (3), and then enters the secondary SO2 absorption spray layer (7) and the tertiary SO2 absorption spray layer (8) in turn after cooling and preliminary absorption to perform desulfurization absorption reaction, and finally enters the demister (9) for dehydration and demisting before being directly discharged through the top chimney flue gas outlet (10); The mixed liquid after absorbing sulfur dioxide from the secondary SO2 absorption spray layer (7) and the tertiary SO2 absorption spray layer (8) enters the slurry circulation pool (11) through the liquid accumulator (4); The absorption liquid pumped out by the slurry circulation pool (11) is discharged into the first filter (22) through the slurry pool discharge pump (21), enters the evaporation concentration slurry pool (26) after filtration, and is pumped into the evaporation concentration spray layer (3) by the evaporation concentration circulation pump (12) for circulation evaporation concentration; The absorption liquid overflowing from the overflow port (5) of the circulating sedimentation tank (2) is filtered through a second filter (25) to form a filtered clear liquid, and the filtered clear liquid is pumped into the evaporation concentration spray layer (3) through an evaporation concentration circulation pump (12) for recycling and crystallization; A solid-liquid mixture having a solid content of more than 30 wt% and containing magnesium sulfate crystals having a particle size greater than 0.1 mm is discharged from a discharge port (6) at the bottom of the circulating sedimentation tank (2), and the solid-liquid mixture is sent to a crystallization tank (16). The mixture is cooled in the crystallization tank (16) to further form magnesium sulfate crystals having a particle size greater than 0.2 mm. In order to prevent crystal sedimentation, a stirring device is provided in the crystallization tank (16). The stirring device may be an air stirring device or an electric stirring device. The solid-liquid mixture entering the crystallization tank (16) from the circulating sedimentation tank (2) is separated in the crystallization tank (16), the mother liquor is returned to the evaporation concentration spray layer (3) for further circulation crystallization, the crystal slurry with a solid content greater than 40wt% is sent to the centrifuge (17) for separation, the mother liquor in the centrifuge is returned to the evaporation concentration spray layer (3), and the dry cooler (18) with a water content less than 2wt% is further dried to a finished product and sent to a packaging machine (19).

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