Device for carbonation reaction of desulfurization gypsum

Abstract

The invention discloses a device for carbonation reaction of desulfurization gypsum, and belongs to the technical field of chemical production equipment, the device comprises a reactor shell, an isolator is arranged in the reactor shell, the inner space of the reactor shell is divided into a calcium sulfate leaching area and a carbonation reaction area by the isolator, the isolator comprises a leaching layer, and the leaching layer is arranged in the reactor shell. The internal space of the reaction device is divided by the isolator, so that the dissolution process and the carbonation reaction process of calcium sulfate are carried out in different spaces, the space for generating calcium carbonate is separated from the space where calcium sulfate particles are located, and the produced calcium carbonate cannot be polymerized on the surfaces of the calcium sulfate particles to influence the conversion of calcium sulfate; therefore, the conversion rate of calcium sulfate is higher, and the problem that calcium carbonate generated by carbonation reaction is easy to polymerize on the surfaces of calcium sulfate particles and the conversion rate of calcium sulfate is influenced due to the fact that the dissolution and reaction processes of desulfurized gypsum are carried out in the same space in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of chemical production equipment, in particular to a device for carbonation reaction of desulfurized gypsum. Background Art

[0002] The carbonation reaction of desulfurized gypsum refers to the reaction of calcium sulfate dihydrate, the main component of desulfurized gypsum, with carbon dioxide to produce calcium carbonate. At present, the carbonation of desulfurized gypsum mainly adopts the wet process, that is, the reaction of desulfurized gypsum slurry and carbonation reagent, which is a solid-liquid-gas heterogeneous reaction. The carbonation reaction of calcium sulfate mainly has three steps: first, calcium sulfate partially dissolves under the conditions of appropriate pH value and leaching agent, and releases Ca into the solution. 2+ and SO4 2- ions; second, CO2 gas is absorbed and hydrolyzed in the solution to produce CO3 2- ions; the third is Ca 2+ and CO3 2- The reaction generates CaCO3, which in turn promotes the continuous dissolution and ionization of calcium sulfate. The existing technology is that these three steps are carried out in the same reactor, that is, calcium sulfate dissolution, gas absorption and calcium carbonate generation are completed in a spatial system. Although this reactor has a simple structure, it is difficult to control the reaction kinetics. The calcium carbonate generated by the carbonation reaction is easily aggregated on the surface of calcium sulfate particles, hindering the material transfer between solid particles and liquid phase, thereby affecting the conversion rate. On the other hand, in a system where desulfurized gypsum and carbon dioxide gas are in direct contact, it usually causes localized Ca 2+ / CO3 2- If the concentration ratio is too high, the resulting calcium carbonate precipitate is a mixture of multiple crystal forms. Calcium carbonate exists in three types of crystals: calcite, vaterite and aragonite. Different crystal forms of calcium carbonate have different uses. The reaction to form polycrystalline calcium carbonate is not conducive to the subsequent resource utilization and value.

[0003] For example, the "method for absorbing carbon dioxide from power plant tail gas with desulfurized gypsum" disclosed in Chinese patent documents, with the publication number CN114702056A, includes the following steps: slurrying desulfurized gypsum or natural gypsum with ammonia solution, and fully contacting with carbon dioxide gas released by the power plant after desulfurization and denitrification, and absorbing the generated calcium carbonate and ammonium sulfate solution through desulfurized gypsum slurry and ammonia solution. The disadvantage of this patent is that the dissolution and reaction process of desulfurized gypsum is carried out in the reaction tank, and the calcium carbonate generated by the carbonation reaction is easy to aggregate on the surface of calcium sulfate particles, which will affect the conversion rate of calcium sulfate and generate polycrystalline calcium carbonate, which makes subsequent treatment difficult. Summary of the invention

[0004] The present invention aims to overcome the problem in the prior art that the dissolution and reaction processes of desulfurized gypsum are carried out in the same space, resulting in that calcium carbonate generated by the carbonation reaction is easily aggregated on the surface of calcium sulfate particles, which affects the conversion rate of calcium sulfate. A device for the carbonation reaction of desulfurized gypsum is provided, which can respectively carry out the dissolution and carbonation reactions of desulfurized gypsum in different spaces of the same device, thereby avoiding that the produced calcium carbonate affects the conversion rate.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions: The present invention provides a device for carbonation reaction of desulfurized gypsum, comprising a reactor shell, wherein an isolator is arranged inside the reactor shell, wherein the isolator divides the internal space of the reactor shell into a calcium sulfate leaching zone and a carbonation reaction zone, wherein the isolator comprises a leaching layer, wherein a first feed inlet is arranged on the calcium sulfate leaching zone, and a second feed inlet is arranged on the carbonation reaction zone.

[0006] In the present application, the internal space of the reaction device is divided by an isolator, so that the dissolution process of calcium sulfate and the carbonation reaction process are carried out in different spaces, thereby separating the space where calcium carbonate is generated from the space where the calcium sulfate particles are located, and the produced calcium carbonate will not aggregate on the surface of the calcium sulfate particles to affect the conversion of calcium sulfate, thereby making the conversion rate of calcium sulfate higher.

[0007] Preferably, the leached layer is a hydrophilic porous membrane, and the pore size of the holes on the porous membrane is 1-5 micron. Through the porous membrane, the calcium sulfate dissolved in the liquid can be moved from the calcium sulfate leaching zone to the carbonation reaction zone, and the calcium sulfate particles in the calcium sulfate leaching zone are prevented from entering the carbonation reaction zone, and the carbon dioxide gas in the carbonation reaction zone is prevented from entering the calcium sulfate leaching zone.

[0008] Preferably, the porous membrane is a hydrophilic polyvinylidene fluoride filter membrane or a hydrophilic polyethersulfone filter membrane.

[0009] Preferably, the separator is a multi-layer structure, which includes metal structural layers located on both sides of the leaching layer, and the porous membrane is easily fixed by the metal structural layers.

[0010] Preferably, the metal structural layers are all metal sieve plates, which are provided with a plurality of sieve holes, so that the solution leached from the calcium sulfate leaching area to the carbonation reaction area is more uniform.

[0011] Preferably, the calcium sulfate leaching zone is located in the carbonation reaction zone, and a support rod is provided between the isolation layer and the reactor shell.

[0012] Preferably, stirring structures are provided in both the calcium sulfate leaching zone and the carbonation reaction zone.

[0013] Preferably, the stirring structure in the calcium sulfate leaching zone is a top-entry stirrer, and the stirring structure in the carbonation reaction zone is a side-entry stirrer.

[0014] Preferably, an ultrasonic probe is installed in the calcium sulfate leaching area, and the ultrasonic probe is used to emit ultrasonic pulses into the calcium sulfate leaching area.

[0015] Therefore, the present invention has the following beneficial effects: (1) The reactor is divided into two areas, and the dissolved ions in the calcium sulfate leaching area can migrate to the gas absorption and solid phase precipitation area through the isolator. The isolator can also effectively block gas permeation, thereby separating the calcium sulfate dissolution process and the calcium carbonate production process, and effectively preventing calcium carbonate precipitation from coating calcium sulfate; (2) Compared with multi-media reactions in the same area, the reactor needs to pass through the isolator from the release of calcium ions to the generation of calcium carbonate, which is conducive to the uniform dispersion of reactants and products in the reactor, avoiding local excessive concentration and particle aggregation, and helping to form single crystal calcium carbonate; (3) The side-entry agitator can form annular plug flow and radial turbulence in the gas absorption and solid phase precipitation area. Combined with ultrasound, it can fully disperse the gas and solid and better promote the reaction. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the present invention.

[0017] Figure 2 It is a structural diagram of embodiment 3 of the present invention.

[0018] Figure 3 It is a structural diagram of embodiment 4 of the present invention.

[0019] In the figure: reactor shell 1 isolator 2 calcium sulfate leaching zone 3 carbonation reaction zone 4 first feed inlet 5 top-entry stirrer 6 ultrasonic probe 7 second feed inlet 8 support rod 9 side-entry stirrer 10 gas pipe 11 discharge port 12 partition structure 13 partition drive structure 14. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0021] Embodiment 1, as Figure 1 As shown, a device for carbonation reaction of desulfurized gypsum includes a reactor shell 1, which is a vertical cylindrical shape and has a spherical bottom. An isolator 2 is arranged inside the reactor shell 1, and the isolator 2 divides the internal space of the reactor shell 1 into a calcium sulfate leaching area 3 and a carbonation reaction area 4.

[0022] The calcium sulfate leaching area 3 and the carbonation reaction area 4 are distributed in an inside-outside manner. The calcium sulfate leaching area 3 is located inside the carbonation reaction area 4. The side and bottom surfaces of the calcium sulfate leaching area 3 are covered by the isolator 2, and the top surface of the calcium sulfate leaching area 3 is covered by the top of the reactor shell 1, and the carbonation reaction area 4 is covered by the entire reaction area shell. The height of the calcium sulfate leaching area 3 is 70% of the diameter of the reactor shell 1, and the diameter of the calcium sulfate leaching area 3 is 40% of the diameter of the reactor shell 1. The calcium sulfate leaching area 3 is provided with a first feed port 5, and the carbonation reaction area 4 is provided with a second feed port 8. The first feed port 5 and the second feed port 8 are both located at the top of the reactor shell 1, connecting the inner and outer spaces of the reactor shell 1, and are used to feed into the reactor shell 1. A discharge port 12 connecting the inner and outer spaces of the reactor is provided at the bottom of the carbonation reaction area 4, which is used to recover the generated calcium carbonate.

[0023] The isolator 2 includes a leaching layer, which is a hydrophilic porous membrane, and the pore size of the holes on the porous membrane is 1-5 microns. In this embodiment, the leaching layer is a hydrophilic polyvinylidene fluoride (PVDF) filter membrane with a pore size of 2 microns. The isolator 2 is a multilayer structure with three layers, and also includes a metal structure layer located on both sides of the leaching layer. The metal structure layer is a stainless steel sieve plate, which is provided with a plurality of sieve holes to prevent the position of calcium sulfate leaching from being too concentrated. The lower part of the isolator 2 is connected to the reactor housing 1 by a support rod 9 made of stainless steel. There are four support rods 9, and the four support rods 9 are evenly distributed at 90° intervals on the outside of the isolator 2 to fix the lower structure of the isolator 2, and the upper part of the isolator 2 is directly fixed to the top of the reactor housing 1.

[0024] A top-entry stirrer 6 is installed in the calcium sulfate leaching zone 3, and the top-entry stirrer 6 passes through the shell from the top center of the reactor shell 1 downward into the inside of the calcium sulfate leaching zone 3, and its stirring shaft is arranged in the vertical direction. An ultrasonic probe 7 is also installed inside the calcium sulfate leaching zone 3 for generating ultrasonic pulses inside the device. A side-entry stirrer 10 is installed in the calcium carbonate reaction zone, and the side-entry stirrer 10 is located at a position near the bottom of the side wall of the reactor shell 1, and its stirring shaft is arranged in the horizontal direction. A gas pipe 11 connected to the inside and outside of the reactor shell 1 is also installed in the calcium carbonate reactor, and the gas pipe 11 is used to pass carbon dioxide gas.

[0025] When using the present application, desulfurized gypsum, ammonia and glycine solution are added from the first feed port 5, ammonia water is added from the second feed port 8, and carbon dioxide is passed from the gas pipe 11. In the calcium sulfate leaching area 3, the desulfurized gypsum will partially dissolve, and calcium ions and sulfate ions are released in the solution, and the top-entry mixer 6 will accelerate the dissolution process. At the same time, in the carbonation reaction area 4, carbon dioxide gas will dissolve in the liquid to produce carbonate ions. Due to the presence of the leaching layer of the separator 2, solids and gases will not be exchanged between the calcium sulfate leaching area 3 and the carbonation reaction area 4, and the calcium ions and sulfate ions dissolved from the desulfurized gypsum will leach into the carbonation reaction area 4 for reaction. In this way, the calcium sulfate particles always remain in the calcium sulfate leaching area 3, and the generated calcium carbonate is generated in the carbonation reaction area 4, and will not be coated on the outside of the calcium sulfate, thereby avoiding the problem of insufficient conversion rate caused by particle coating. At the same time, due to the presence of the mixer and the ultrasonic probe 7, the gas and the fixation can be fully dispersed in the solution, which better promotes the reaction. The rate of carbon dioxide introduction through the gas pipe 11 was controlled, and the reaction was carried out for 3 hours under stirring and ultrasound to prepare vaterite-type calcium carbonate with a purity of 96%, and the reaction conversion rate of calcium sulfate was greater than 98%.

[0026] Embodiment 2, as Figure 1 As shown, a device for carbonation reaction of desulfurized gypsum includes a reactor shell 1, which is a vertical cylindrical shape and has a spherical bottom. An isolator 2 is arranged inside the reactor shell 1, and the isolator 2 divides the internal space of the reactor shell 1 into a calcium sulfate leaching area 3 and a carbonation reaction area 4.

[0027] The calcium sulfate leaching area 3 and the carbonation reaction area 4 are distributed in an inside-outside manner. The calcium sulfate leaching area 3 is located inside the carbonation reaction area 4. The side and bottom surfaces of the calcium sulfate leaching area 3 are covered by the isolator 2, and the top surface of the calcium sulfate leaching area 3 is covered by the top of the reactor shell 1, and the carbonation reaction area 4 is covered by the entire reaction area shell. The height of the calcium sulfate leaching area 3 is 70% of the diameter of the reactor shell 1, and the diameter of the calcium sulfate leaching area 3 is 40% of the diameter of the reactor shell 1. The calcium sulfate leaching area 3 is provided with a first feed port 5, and the carbonation reaction area 4 is provided with a second feed port 8. The first feed port 5 and the second feed port 8 are both located at the top of the reactor shell 1, connecting the inner and outer spaces of the reactor shell 1, and are used to feed into the reactor shell 1. A discharge port 12 connecting the inner and outer spaces of the reactor is provided at the bottom of the carbonation reaction area 4, which is used to recover the generated calcium carbonate.

[0028] The separator 2 includes a leaching layer, and the leaching layer is a hydrophilic porous membrane, and the pore size of the hole on the porous membrane is 1-5 microns. In the present embodiment, the leaching layer is a hydrophilic polyethersulfone filter membrane with a pore size of 2 microns. The separator 2 is a multilayer structure, and has three layers, and also includes a metal structure layer located on both sides of the leaching layer, and the metal structure layer is a stainless steel sieve plate, which is provided with several sieve holes, for avoiding the position of calcium sulfate leaching to be too concentrated. The lower part of the separator 2 is connected with the reactor housing 1 by a support rod 9 of stainless steel material, and the number of the support rod 9 is four, and four support rods 9 are evenly distributed at 90 ° intervals in the outer circumferential direction of the separator 2, for fixing the lower structure of the separator 2, and the upper part of the separator 2 is directly fixed on the top of the reactor housing 1.

[0029] A top-entry stirrer 6 is installed in the calcium sulfate leaching zone 3, and the top-entry stirrer 6 passes through the shell from the top center of the reactor shell 1 downward into the inside of the calcium sulfate leaching zone 3, and its stirring shaft is arranged in the vertical direction. An ultrasonic probe 7 is also installed inside the calcium sulfate leaching zone 3 for generating ultrasonic pulses inside the device. A side-entry stirrer 10 is installed in the calcium carbonate reaction zone, and the side-entry stirrer 10 is located at a position near the bottom of the side wall of the reactor shell 1, and its stirring shaft is arranged in the horizontal direction. A gas pipe 11 connected to the inside and outside of the reactor shell 1 is also installed in the calcium carbonate reactor, and the gas pipe 11 is used to pass carbon dioxide gas.

[0030] When using the present application, desulfurized gypsum and sodium hydroxide solution are added from the first feed port 5, sodium hydroxide solution is added from the second feed port 8, and carbon dioxide is passed from the gas pipe 11. In the calcium sulfate leaching area 3, the desulfurized gypsum will partially dissolve, and calcium ions and sulfate ions are released in the solution, and the top-entry mixer 6 will accelerate the dissolution process. At the same time, in the carbonation reaction area 4, carbon dioxide gas will dissolve in the liquid to produce carbonate ions. Due to the presence of the leaching layer of the separator 2, solids and gases will not be exchanged between the calcium sulfate leaching area 3 and the carbonation reaction area 4, and the calcium ions and sulfate ions dissolved from the desulfurized gypsum will leach into the carbonation reaction area 4 for reaction. In this way, the calcium sulfate particles always remain in the calcium sulfate leaching area 3, and the generated calcium carbonate is generated in the carbonation reaction area 4, and will not be coated on the outside of the calcium sulfate, thereby avoiding the problem of insufficient conversion rate caused by particle coating. At the same time, due to the presence of the mixer and the ultrasonic probe 7, the gas and the fixed can be fully dispersed in the solution, which better promotes the reaction. The rate of carbon dioxide introduction through the gas pipe 11 was controlled, and the mixture was reacted for 2 hours under stirring and ultrasound, thereby preparing calcite-type calcium carbonate with a purity of 92%, and a calcium sulfate reaction conversion rate of greater than 98%.

[0031] Embodiment three, as Figure 2As shown, a device for carbonation reaction of desulfurized gypsum includes a reactor shell 1, which is a vertical cylindrical shape and has a spherical bottom. An isolator 2 is arranged inside the reactor shell 1, and the isolator 2 divides the internal space of the reactor shell 1 into a calcium sulfate leaching area 3 and a carbonation reaction area 4.

[0032] The calcium sulfate leaching area 3 and the carbonation reaction area 4 are distributed in an inside-outside manner. The calcium sulfate leaching area 3 is located inside the carbonation reaction area 4. The side and bottom surfaces of the calcium sulfate leaching area 3 are covered by the isolator 2, and the top surface of the calcium sulfate leaching area 3 is covered by the top of the reactor shell 1, and the carbonation reaction area 4 is covered by the entire reaction area shell. The height of the calcium sulfate leaching area 3 is 70% of the diameter of the reactor shell 1, and the diameter of the calcium sulfate leaching area 3 is 40% of the diameter of the reactor shell 1. The calcium sulfate leaching area 3 is provided with a first feed port 5, and the carbonation reaction area 4 is provided with a second feed port 8. The first feed port 5 and the second feed port 8 are both located at the top of the reactor shell 1, connecting the inner and outer spaces of the reactor shell 1, and are used to feed into the reactor shell 1. A discharge port 12 connecting the inner and outer spaces of the reactor is provided at the bottom of the carbonation reaction area 4, which is used to recover the generated calcium carbonate.

[0033] The isolator 2 includes a leaching layer, which is a hydrophilic porous membrane, and the pore size of the holes on the porous membrane is 1-5 microns. In this embodiment, the leaching layer is a hydrophilic polyvinylidene fluoride (PVDF) filter membrane with a pore size of 2 microns. The isolator 2 is a multilayer structure with three layers, and also includes a metal structure layer located on both sides of the leaching layer. The metal structure layer is a stainless steel sieve plate, which is provided with a plurality of sieve holes to prevent the position of calcium sulfate leaching from being too concentrated. The lower part of the isolator 2 is connected to the reactor housing 1 by a support rod 9 made of stainless steel. There are four support rods 9, and the four support rods 9 are evenly distributed at 90° intervals on the outside of the isolator 2 to fix the lower structure of the isolator 2, and the upper part of the isolator 2 is directly fixed to the top of the reactor housing 1.

[0034] A top-entry stirrer 6 is installed in the calcium sulfate leaching zone 3, and the top-entry stirrer 6 passes through the shell from the top center of the reactor shell 1 downward into the inside of the calcium sulfate leaching zone 3, and its stirring shaft is arranged in the vertical direction. An ultrasonic probe 7 is also installed inside the calcium sulfate leaching zone 3 for generating ultrasonic pulses inside the device. A side-entry stirrer 10 is installed in the calcium carbonate reaction zone, and the side-entry stirrer 10 is located at a position near the bottom of the side wall of the reactor shell 1, and its stirring shaft is arranged in the horizontal direction. A gas pipe 11 connected to the inside and outside of the reactor shell 1 is also installed in the calcium carbonate reactor, and the gas pipe 11 is used to pass carbon dioxide gas.

[0035] The calcium sulfate leaching area 3 and the carbonation reaction area 4 are also equipped with a partition structure 13 located on one side of the isolator 2, and a partition drive structure 14 is also installed on the reactor shell 1. The partition structure 13 is a rotating drum that can rotate relative to the isolator 2 in the reactor shell 1, and the rotating drum is provided with a plurality of through holes, and the through holes correspond to the sieve holes on the isolator 2 one by one. In the working state, the through holes on the rotating drum correspond to the positions of the sieve holes on the isolator 2, and ions can be exchanged between the calcium sulfate leaching area 3 and the carbonation reaction area 4. When the rotating drum rotates a certain angle, the through holes on the rotating drum are staggered with the positions of the sieve holes on the isolator 2, and the calcium sulfate leaching area 3 and the carbonation reaction area 4 are separated, and ion exchange cannot be performed. The upper end of the rotating drum is located above the reactor shell 1, and an internal thread is provided on its inner side. The partition drive structure 14 includes a drive motor and a drive gear, and the drive gear is meshed with the upper end of the rotating drum.

[0036] When using the present application, desulfurized gypsum, ammonia and glycine solution are added from the first feed port 5, and aqueous ammonia is added from the second feed port 8. In the calcium sulfate leaching zone 3, the desulfurized gypsum will partially dissolve, and release calcium ions and sulfate ions in the solution, and the top-entry mixer 6 will accelerate the dissolution process. In the initial state, the through hole on the drum corresponds to the sieve hole position of the isolator 2, and at this time, ion exchange can be carried out between the calcium sulfate leaching zone 3 and the carbonation reaction zone 4. As the desulfurized gypsum dissolves, the ion concentration in the calcium sulfate leaching zone 3 gradually increases and leaches into the carbonation reaction zone 4. After a period of time, the drum of the partition structure 13 rotates, and the through hole on the drum is staggered from the sieve hole position of the isolator 2, so that the calcium sulfate leaching zone 3 and the carbonation reaction zone 4 are completely isolated. At this time, carbon dioxide is introduced from the gas pipe 11 to prevent carbonate ions from entering the calcium sulfate leaching due to the increase in ion concentration in the carbonation reaction zone 4. Under the action of the side-entry agitator 10, calcium carbonate is continuously produced in the carbonation reaction zone 4. After a period of time, the leached calcium ions have basically formed calcium carbonate, and the side-entry agitator 10 is stopped to allow the calcium carbonate to precipitate and be discharged from the bottom of the reactor shell 1. Then, the drum of the partition structure 13 is rotated again to cycle the whole process.

[0037] Embodiment 4, as Figure 3 As shown, a device for carbonation reaction of desulfurized gypsum includes a reactor shell 1, which is a vertical cylindrical shape and has a spherical bottom. An isolator 2 is arranged inside the reactor shell 1, and the isolator 2 divides the internal space of the reactor shell 1 into a calcium sulfate leaching area 3 and a carbonation reaction area 4.

[0038] The calcium sulfate leaching area 3 and the carbonation reaction area 4 are distributed in a left-right manner, and the calcium sulfate leaching area 3 and the carbonation reaction area 4 are respectively located on the left and right sides of the internal space of the reactor shell 1. The calcium sulfate leaching area 3 and the carbonation reaction area 4 are separated by an isolator 2, and the rest is covered by the top of the reactor shell 1. The calcium sulfate leaching area 3 is provided with a first feed port 5, and the carbonation reaction area 4 is provided with a second feed port 8. The first feed port 5 and the second feed port 8 are both located at the top of the reactor shell 1, connecting the inner and outer spaces of the reactor shell 1, and are used to add materials to the inside of the reactor shell 1. A discharge port 12 connected to the inner and outer spaces of the reactor is provided at the bottom of the carbonation reaction area 4, which is used to recover the generated calcium carbonate.

[0039] The isolator 2 includes a leaching layer, which is a hydrophilic porous membrane, and the pore size of the holes on the porous membrane is 1-5 microns. In this embodiment, the leaching layer is a hydrophilic polyvinylidene fluoride (PVDF) filter membrane with a pore size of 2 microns. The isolator 2 is a multilayer structure with three layers, and also includes a metal structure layer located on both sides of the leaching layer. The metal structure layer is a stainless steel sieve plate, which is provided with a plurality of sieve holes to prevent the position of calcium sulfate leaching from being too concentrated. The lower part of the isolator 2 is connected to the reactor housing 1 by a support rod 9 made of stainless steel. There are four support rods 9, and the four support rods 9 are evenly distributed at 90° intervals on the outside of the isolator 2 to fix the lower structure of the isolator 2, and the upper part of the isolator 2 is directly fixed to the top of the reactor housing 1.

[0040] A top-entry stirrer 6 is installed in the calcium sulfate leaching zone 3, and the top-entry stirrer 6 passes through the shell from the top center of the reactor shell 1 downwards to enter the inside of the calcium sulfate leaching zone 3, and its stirring shaft is arranged in the vertical direction. An ultrasonic probe 7 is also installed inside the calcium sulfate leaching zone 3 for generating ultrasonic pulses inside the device. A top-entry stirrer 6 is installed in the calcium carbonate reaction zone, and the top-entry stirrer 6 passes through the shell from the top center of the reactor shell 1 downwards to enter the inside of the carbonation reaction zone 4, and its stirring shaft is arranged in the vertical direction. A gas pipe 11 connected to the inside and outside of the reactor shell 1 is also installed in the calcium carbonate reactor, and the gas pipe 11 is used to pass carbon dioxide gas.

[0041] The calcium sulfate leaching area 3 and the carbonation reaction area 4 are also equipped with a partition structure 13 located on one side of the isolator 2, and a partition drive structure 14 is also installed on the reactor shell 1. The partition structure 13 is a partition that can be raised and lowered in the reactor shell 1, and a plurality of through holes are provided on the partition, and the through holes correspond to the sieve holes on the isolator 2 one by one. In the working state, the through holes on the rotating drum correspond to the positions of the sieve holes on the isolator 2, and ions can be exchanged between the calcium sulfate leaching area 3 and the carbonation reaction area 4. When the partition structure 13 moves, the through holes on the rotating drum are staggered with the positions of the sieve holes on the isolator 2, and the calcium sulfate leaching area 3 and the carbonation reaction area 4 are separated, and ion exchange cannot be performed. The partition is connected to the partition drive structure 14 through a suspension rope above, and the partition drive structure 14 includes a drive motor and a winding reel, and the suspension rope is installed on the winding reel.

[0042] When using the present application, desulfurized gypsum, ammonia and glycine solution are added from the first feed port 5, ammonia water is added from the second feed port 8, and carbon dioxide is passed from the gas pipe 11. In the calcium sulfate leaching area 3, the desulfurized gypsum will partially dissolve, and calcium ions and sulfate ions are released in the solution, and the top-entry mixer 6 will accelerate the dissolution process. At the same time, in the carbonation reaction area 4, carbon dioxide gas will dissolve in the liquid to produce carbonate ions. Due to the presence of the leaching layer of the separator 2, solids and gases will not be exchanged between the calcium sulfate leaching area 3 and the carbonation reaction area 4, and the calcium ions and sulfate ions dissolved from the desulfurized gypsum will leach into the carbonation reaction area 4 for reaction. In this way, the calcium sulfate particles always remain in the calcium sulfate leaching area 3, and the generated calcium carbonate is generated in the carbonation reaction area 4, and will not be coated on the outside of the calcium sulfate, thereby avoiding the problem of insufficient conversion rate caused by particle coating. At the same time, due to the presence of the mixer and the ultrasonic probe 7, the gas and the fixation can be fully dispersed in the solution, which better promotes the reaction. The rate of carbon dioxide introduction through the gas pipe 11 was controlled, and the reaction was carried out for 3 hours under stirring and ultrasound to prepare vaterite-type calcium carbonate with a purity of 96%, and the reaction conversion rate of calcium sulfate was greater than 98%.

Claims

1. A device for carbonation reaction of desulfurized gypsum, comprising a reactor shell, characterized in that: An isolator is arranged inside the reactor shell, and the isolator divides the internal space of the reactor shell into a calcium sulfate leaching zone and a carbonation reaction zone. The isolator comprises a leaching layer, a first feed inlet is arranged on the calcium sulfate leaching zone, and a second feed inlet is arranged on the carbonation reaction zone.

2. A device for carbonation reaction of desulfurized gypsum according to claim 1, characterized in that: The leaching layer is a hydrophilic porous membrane, and the pores on the porous membrane have a diameter of 1-5 microns.

3. A device for carbonation reaction of desulfurized gypsum according to claim 2, characterized in that: The porous membrane is a hydrophilic polyvinylidene fluoride filter membrane or a hydrophilic polyethersulfone filter membrane.

4. The device for carbonation reaction of desulfurized gypsum according to claim 1, characterized in that: The separator is a multi-layer structure, which includes metal structure layers located on both sides of the leaching layer.

5. A device for carbonation reaction of desulfurized gypsum according to claim 4, characterized in that: The metal structural layers are all metal sieve plates, which are provided with a plurality of sieve holes.

6. A device for carbonation reaction of desulfurized gypsum according to claim 1, characterized in that: The calcium sulfate leaching zone is located in the carbonation reaction zone, and a support rod is arranged between the isolation layer and the reactor shell.

7. The device for carbonation reaction of desulfurized gypsum according to claim 1, characterized in that: Stirring structures are provided in the calcium sulfate leaching zone and the carbonation reaction zone.

8. The device for carbonation reaction of desulfurized gypsum according to claim 7, characterized in that: The stirring structure in the calcium sulfate leaching zone is a top-entry stirrer, and the stirring structure in the carbonation reaction zone is a side-entry stirrer.

9. A device for carbonation reaction of desulfurized gypsum according to any one of claims 1 to 8, characterized in that: An ultrasonic probe is also installed in the calcium sulfate leaching area.

10. A device for carbonation reaction of desulfurized gypsum according to any one of claims 1 to 8, characterized in that: The calcium sulfate leaching zone and the carbonation reaction zone are also equipped with a partition structure located on one side of the separator, and the reactor shell is also equipped with a partition driving structure.

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