Iron and steel plant waste heat steam collecting equipment and application thereof in autoclaved building material production

Abstract

The invention discloses steel plant waste heat steam collecting equipment and application thereof in autoclaved building material production, and relates to the technical field of energy recycling, the steel plant waste heat steam collecting equipment comprises a heat exchange part and further comprises a collecting part; the heat exchange part comprises a heat exchange cylinder, a heat preservation inner cylinder is fixedly mounted in the heat exchange cylinder, and a first heat exchange assembly, a second heat exchange assembly and a third heat exchange assembly are fixedly mounted in the heat preservation inner cylinder; the first heat exchange assembly, the second heat exchange assembly and the third heat exchange assembly each comprise a heat exchange box and a heat conduction cone fixedly installed in the heat exchange box. The steel plant waste heat steam collecting device has the advantages that when steam is collected, the steam is recycled through natural floating of the steam, the steam guide pipe is blocked in the recycling process, steam heat loss caused by entering of external air is avoided, the steel plant waste heat steam collecting device is applied to autoclaved building material production, the production energy consumption of autoclaved building materials is greatly reduced, and the production cost of the autoclaved building materials is reduced. The method has great economic benefits.

Description

Technical Field

[0001] The invention relates to the technical field of energy recovery and utilization, and in particular to a steel plant waste heat steam collection device and application thereof in the production of steam-pressed building materials. Background Art

[0002] In the rolling mill of a steel plant, steel needs to be heated in a heating furnace for subsequent rolling operations. The heated steel needs to be placed in a water pool for rapid cooling and quenching. After the steel enters the water pool, the water in the pool will instantly vaporize to form steam under the action of high temperature. In order to improve the utilization of steam, the waste heat steam needs to be collected.

[0003] The existing waste heat steam is collected by a smoke hood, and the waste heat steam is sucked into the smoke hood by the fan in the smoke hood, and then utilized. Therefore, the publication number CN216925183U discloses a smoke hood for collecting smoke, which includes a smoke hood, and two shielding covers are movably installed on the bottom side of the smoke hood, and the extrusion covers are rotatably installed on the two shielding covers, and sliding brackets are fixedly installed on the two shielding covers, and four sliding brackets are movably installed on the smoke hood. A motor is fixedly installed on one side of the smoke hood, and a driving seat is fixedly installed on the two shielding covers. Threaded holes are opened on the two driving seats, and a first screw rod and a second screw rod are respectively threadedly installed in the two threaded holes, and the threads on the first screw rod and the second screw rod are opposite.

[0004] The above-mentioned smoke hood is provided with two shielding covers, so that when the smoke hood is stopped, the first screw rod and the second screw rod rotate in opposite directions to drive the two driving seats to approach each other, so that the outlet of the smoke hood is closed by the two shielding covers to prevent dust from being scattered, and the two shielding covers can also collect the fallen dust to avoid pollution;

[0005] By setting the pushing frame and the knocking block, when the two shielding covers are closed, the pushing frame can drive the knocking block to intermittently knock the inner wall of the smoke hood, so that the smoke and dust on the inner wall of the smoke hood can be shaken off and collected by the shielding covers, further avoiding pollution.

[0006] When the above-mentioned smoke hood and the existing smoke hood are in use, air other than waste heat steam around the bottom of the smoke hood will be sucked into the smoke hood during suction. Since the temperature of the air is lower than that of the waste heat steam, the heat of the waste heat steam will be lost. At the same time, the collected waste heat steam needs to be filtered, and this process will cause some heat loss, thereby causing the waste heat steam to condense prematurely and reducing the heat utilization rate.

[0007] Therefore, a new type of steel plant waste heat steam collection equipment and its application in aerated concrete can be used to solve the shortcomings of the prior art. Summary of the invention

[0008] The purpose of the present invention is to solve the problem in the prior art that more heat loss leads to lower energy utilization rate, and to propose a steel plant waste heat steam collection device and its application in the production of autoclaved building materials.

[0009] In order to achieve the above object, the present invention adopts the following technical solutions:

[0010] A steam waste heat collection device for a steel plant, comprising a heat exchange part and a collection part;

[0011] The heat exchange part comprises a heat exchange cylinder, a heat preservation inner cylinder is fixedly installed inside the heat exchange cylinder, and a first heat exchange component, a second heat exchange component and a third heat exchange component are fixedly installed inside the heat preservation inner cylinder;

[0012] The first heat exchange assembly, the second heat exchange assembly and the third heat exchange assembly all include a heat exchange box and a heat-conducting cone fixedly installed inside the heat exchange box, and each of the heat exchange boxes is fixedly connected to a flow guide bucket outside, a booster assembly is installed between the heat exchange box and the heat exchange cylinder in the first heat exchange assembly, and a plurality of heat transfer assemblies matching the corresponding heat exchange boxes are installed on the heat exchange cylinder;

[0013] The collecting part comprises a smoke hood, a steam guide pipe is fixedly connected to the smoke hood, the steam guide pipe is fixedly connected to the heat exchange cylinder, and a steam separation component is installed on the steam guide pipe.

[0014] Preferably, a swirl blade is fixedly installed in each of the heat exchange boxes, and the heat conduction cones in each of the heat exchange boxes are arranged in a staggered manner.

[0015] Preferably, the boosting assembly includes a piston plate slidably mounted inside the heat exchange box, a plurality of through holes are provided on the piston plate and the heat exchange box, a one-way tube is fixedly mounted in each of the through holes, a driving mechanism cooperating with the piston plate is installed on the heat exchange cylinder, and a sealing mechanism cooperating with the heat exchange box is installed on the heat exchange cylinder.

[0016] Preferably, the driving mechanism includes a frame fixedly mounted on the outside of the heat exchange cylinder, a second motor fixedly mounted on the frame, a rotating disk fixedly mounted on the driving end of the second motor, an eccentric wheel fixedly mounted on the rotating disk, a connecting rod rotatably mounted on the eccentric wheel, a sleeve fixedly mounted on the frame, a slide plate slidably mounted in the sleeve, the slide plate and the connecting rod are rotatably connected, a push rod fixedly mounted on the end of the slide plate away from the connecting rod, and the push rod passes through the heat exchange cylinder and is fixedly connected to the piston plate.

[0017] Preferably, the blocking mechanism comprises a partition fixedly mounted on the heat exchange cylinder, the heat exchange cylinder is divided into two sections by the partition, an intermittent gear ring and a gear disc meshing with the intermittent gear ring are rotatably mounted on the partition, a first motor is fixedly mounted on the partition, a driving end of the first motor is fixedly connected to the gear disc, and a circular hole matching the heat exchange box is opened on the partition;

[0018] A plurality of incomplete toothed discs are rotatably mounted on the partition, each of which is meshed with an intermittent toothed ring, and a sealing disc matching a circular hole is fixedly mounted on each of the incomplete toothed discs, and each of the sealing discs is in contact with the heat exchange box.

[0019] Preferably, the heat transfer component includes a spiral conduit fixedly wound around the outside of the heat exchange box, both ends of the spiral conduit are fixedly connected to a docking conduit, a pump box is fixedly installed outside the heat exchange cylinder, and the two docking conduits extend out of the heat exchange cylinder and are connected to the pump box.

[0020] Preferably, liquid mercury is stored in the pump box that cooperates with the heat exchange box in the first heat exchange assembly, which is mainly used for heat transfer preheating; high-concentration ethanol is stored in the pump box that cooperates with the heat exchange box in the second heat exchange assembly, which is used for vaporization and pressurization; high-concentration ether is stored in the pump box that cooperates with the heat exchange box in the third heat exchange assembly, which is used for vaporization and pressurization.

[0021] Preferably, the steam separation assembly includes a steam separation box fixedly mounted inside the steam duct, a rotating shaft rotatably mounted on the steam separation box, an upper sealing plate abutting the upper end of the steam separation box fixedly mounted on the upper portion of the rotating shaft, and a lower sealing plate abutting the lower end of the steam separation box fixedly mounted on the lower portion of the rotating shaft, a transmission mechanism matching the rotating shaft is mounted on the steam duct; the transmission mechanism includes a motor fixedly mounted outside the steam duct, a driving end of the motor extends into the interior of the steam duct, and the driving end of the motor is connected to the rotating shaft via a bevel gear set.

[0022] The present invention also provides the application of the waste heat steam collecting device in the production of autoclaved building materials.

[0023] The application of the waste heat steam collection device in the production of autoclaved building materials includes the application of the waste heat steam collection device in the production of lead-zinc tailings aerated concrete, including the following steps:

[0024] S1. Preparing concrete slurry: mixing lead-zinc tailings, cement, quicklime and desulfurized gypsum in a mass ratio of 62:24:9:5 to obtain a mixture, adding water, aluminum powder paste and foam stabilizer in mass ratios of 57%, 0.60‰ and 0.256‰ respectively to the mixture, mixing evenly to obtain concrete slurry;

[0025] S2, stirring and foaming;

[0026] S3, pouring test mold;

[0027] S4. Static curing: Place the cast concrete in a static curing room for static curing at 70℃ for 2h;

[0028] S5, demoulding the mold to form a blank;

[0029] S6. Autoclave curing: placing the concrete block in an autoclave curing room for curing, the autoclave pressure is 1.2 MPa, the temperature is 185°C, the temperature is kept constant for 8 hours, and the temperature is lowered to obtain the finished aerated concrete product;

[0030] The static curing room and the autoclave curing room are both connected to the heat exchange component of the waste heat steam collecting device through pipelines, and the heat collected by the waste heat steam collecting device is transferred to the static curing room and the autoclave curing room.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] 1. When collecting waste heat steam, the waste heat steam collection device recovers the heat in the steam for the first time by setting the first heat exchange component, and then recovers the remaining heat in the steam through the second heat exchange component and the third heat exchange component, and reduces the dust on the steam during the first recovery, so that the heat is released faster, and the multi-stage recovery makes the heat recovery more complete, reduces the loss of heat recovery, and improves the energy utilization rate.

[0033] 2. When collecting steam, the waste heat steam collection device drives the upper sealing plate and the lower sealing plate to intermittently seal the top and bottom of the steam separation box by setting a motor and a bevel gear set. This can effectively prevent external air from entering the heat exchange cylinder to cause heat loss when the first heat exchange component is operating, thereby greatly improving the retention of heat in the steam.

[0034] 3. When collecting steam, the waste heat steam collection device seals the steam outlet of the heat exchange box in the first heat exchange component by setting a sealing mechanism. In conjunction with the use of a piston plate, the steam pressure in the heat exchange box can be increased, thereby increasing the temperature of the steam and accelerating the heat release rate of the steam, thereby achieving the purpose of improving the heat recovery efficiency.

[0035] 4. Applying waste heat steam collection equipment to the production of autoclaved building materials greatly reduces the production energy consumption of autoclaved building materials.

[0036] In summary, the present invention utilizes the natural flotation of steam to recover the steam when collecting waste heat steam, and seals the steam pipe during the recovery process to prevent the entry of external air and cause steam heat loss, and after recovery, performs multi-stage heat exchange treatment on the steam to improve the utilization rate of steam heat. In addition, dust mixed in the steam can be removed during heat recovery, which is beneficial to the release of waste heat steam. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings, wherein:

[0038] Figure 1 This is a schematic diagram of the structure of a waste heat steam collection device for a steel plant proposed by the present invention;

[0039] Figure 2 for Figure 1 Detailed schematic diagram of the structure after being rotated to a certain angle;

[0040] Figure 3 for Figure 1 A schematic detailed view of the plan structure along one of the angles;

[0041] Figure 4 for Figure 3 Detailed schematic diagram of the three-dimensional structure along the AA section;

[0042] Figure 5 for Figure 4 A schematic diagram of the enlarged structure of the first heat exchange component and the driving mechanism;

[0043] Figure 6 for Figure 5 Detailed schematic diagram of the structure after being rotated to a certain angle;

[0044] Figure 7 for Figure 6 Detailed schematic diagram of the internal structure of the middle plugging mechanism;

[0045] Figure 8 for Figure 6 A detailed schematic diagram of the enlarged structure of the middle drive mechanism;

[0046] Fig. 9 for Figure 6 A schematic detailed diagram of the planar structure of the first heat exchange component along one of the angles;

[0047] Fig.10 for Fig. 9 Detailed schematic diagram of the three-dimensional structure along the BB section;

[0048] Fig.11 for Fig.10 Detailed schematic diagram of the structure after being rotated to a certain angle;

[0049] Fig.12 for Figure 1 An enlarged structural schematic detail diagram of the final smoke hood;

[0050] Fig.13 for Fig.12 A schematic detailed view of the plan structure along one of the angles;

[0051] Fig.14 for Fig.13 Detailed schematic diagram of the three-dimensional structure along the CC section;

[0052] Fig.15 for Fig.14 The enlarged structural schematic details of the middle motor and steam distribution box;

[0053] Fig.16 for Fig.15 Detailed schematic diagram of the exploded structure;

[0054] Fig.17 This is the relationship between grinding time and specific surface area;

[0055] Fig.18 This is the effect of lead-zinc tailings fineness on the performance of aerated concrete;

[0056] Fig.19 This is the effect of lead-zinc tailings dosage on the performance of aerated concrete;

[0057] Fig. 20 XRD patterns of C5 sample and lead-zinc tailings;

[0058] 1-lead-zinc tailings, 2-green body without static curing, 3-green body after static curing, 4-autoclaved product;

[0059] Fig.21 is the XRD FT-IR spectrum of sample C5;

[0060] 1- green body without static curing, 2- green body after static curing, 3- product after autoclaving;

[0061] Fig. 22 FE-SEM image of C5 sample;

[0062] (a), (a1)-green bodies without static curing, (b), (b1)-green bodies after static curing, (c), (c1)-products after autoclaving;

[0063] Fig.23 for Fig. 22 Energy dispersive spectrometer (EDS) diagram of the marked areas 1 and 2;

[0064] In the figure: 1 heat exchange cylinder, 2 hanging rope, 3 first motor, 4 smoke hood, 5 second motor, 6 pump box, 7 plugging mechanism, 8 docking duct, 9 insulation inner cylinder, 10 first heat exchange component, 11 second heat exchange component, 12 heat exchange box, 13 spiral duct, 14 guide bucket, 15 push rod, 16 rotating disk, 17 eccentric wheel, 18 sleeve, 19 connecting rod, 20 gear plate, 21 intermittent gear ring, 22 incomplete gear plate, 23 plugging disk, 24 heat conduction cone, 25 swirl blade, 26 piston plate, 27 one-way pipe, 28 steam guide pipe, 29 motor, 30 steam distribution box, 31 upper plugging plate, 32 bevel gear set, 33 rotating shaft, 34 lower plugging plate. DETAILED DESCRIPTION

[0065] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0066] Example 1: Reference Figure 1-Figure 11 , a steel plant waste heat steam collection device, comprising a heat exchange part and a collection part;

[0067] The heat exchange part comprises a heat exchange cylinder 1, a heat preservation inner cylinder 9 is fixedly installed inside the heat exchange cylinder 1, and a first heat exchange component 10, a second heat exchange component 11 and a third heat exchange component are fixedly installed inside the heat preservation inner cylinder 9;

[0068] The function of the heat preservation tube 9 is to insulate the heat exchange tube 1 to prevent the heat of the steam in the heat exchange tube 1 from being directly transferred to the heat exchange tube 1 and then absorbed by the external environment, thereby effectively preserving the heat in the steam and reducing heat loss.

[0069] The first heat exchange assembly 10, the second heat exchange assembly 11 and the third heat exchange assembly all include a heat exchange box 12 and a heat conductive cone 24 fixedly installed inside the heat exchange box 12. The outside of each heat exchange box 12 is fixedly connected to a flow guide hopper 14. A booster assembly is installed between the heat exchange box 12 and the heat exchange cylinder 1 in the first heat exchange assembly 10.

[0070] The function of the guide bucket 14 is to guide the steam in the heat exchange tube 1 to ensure that the steam in the heat exchange tube 1 smoothly enters the heat exchange box 12, avoid turbulence in the heat exchange tube 1, cause heat loss, and further reduce the loss of steam heat.

[0071] The steam in the heat exchange cylinder 1 will horizontally pass through the guide bucket 14 into the heat exchange box 12 in the first heat exchange component 10. When the steam contacts the heat exchange box 12, most of the heat will be absorbed by the heat exchange box 12 (the heat exchange box 12 is made of metal material. Considering the cost, the heat exchange box 12 is best made of copper).

[0072] The function of the heat-conducting cone 24 is to increase the contact area between the steam and the heat exchange box 12, thereby accelerating the heat conduction rate. At the same time, increasing the contact area can also effectively improve the heat conduction efficiency. There will be some heat loss in the process of heat conduction. The longer the time, the greater the loss. Therefore, the heat conduction speed is accelerated here to shorten the transfer time, which can reduce the heat loss to a certain extent.

[0073] In addition, the heat-conducting cones 24 are arranged in a staggered manner to form an interception net in the heat exchange box 12. Steam will liquefy on the heat-conducting cones 24, and the liquefaction will cause dust in the steam to adhere to the heat-conducting cones 24, so that the steam can be dust-removed and can be regarded as a filter.

[0074] A swirl blade 25 is fixedly installed in each heat exchange box 12, and the heat conduction cones 24 in each heat exchange box 12 are arranged in a staggered manner. The function of the swirl blade 25 is to make the steam form a swirl after entering the heat exchange box 12. The centrifugal force generated by the swirl can diffuse the steam to the surroundings, increasing the chance of the steam contacting the inner wall of the heat exchange box 12, so that the steam can contact the inner wall of the heat exchange box 12 more thoroughly, the heat exchange efficiency is higher, the heat exchange amount is larger, and the heat loss is lower.

[0075] The booster assembly includes a piston plate 26 slidably mounted inside the heat exchange box 12. A plurality of through holes are provided on the piston plate 26 and the heat exchange box 12. A one-way pipe 27 is fixedly mounted in each through hole. A driving mechanism matching the piston plate 26 is mounted on the heat exchange cylinder 1.

[0076] The booster assembly can increase the steam pressure in the heat exchange box 12, thereby increasing the temperature of the steam and accelerating the heat release rate of the steam, thereby achieving the purpose of improving the heat recovery efficiency.

[0077] When the piston plate 26 moves toward the side close to the heat-conducting cone 24, the space between the heat-conducting cone 24 and the piston plate 26 inside the heat exchange box 12 is compressed (during the compression process, the end of the heat exchange box 12 away from the piston plate 26 needs to be blocked), and the pressure increases to pressurize the steam. Increasing the steam pressure will increase the heat of the steam, thereby improving the heat exchange efficiency;

[0078] The expansion of the space on the other side of the heat exchange box 12 will draw the steam in the heat exchange tube 1 into the heat exchange box 12, which requires the cooperation of a one-way pipe 27, which can prevent the steam from flowing back.

[0079] The driving mechanism includes a frame fixedly mounted on the outside of the heat exchange cylinder 1, a second motor 5 is fixedly mounted on the frame, a rotating disk 16 is fixedly mounted on the driving end of the second motor 5, an eccentric wheel 17 is fixedly mounted on the rotating disk 16, a connecting rod 19 is rotatably mounted on the eccentric wheel 17, a sleeve 18 is fixedly mounted on the frame, a slide plate is slidably mounted in the sleeve 18, the slide plate is rotatably connected to the connecting rod 19, a push rod 15 is fixedly mounted on the end of the slide plate away from the connecting rod 19, and the push rod 15 passes through the heat exchange cylinder 1 and is fixedly connected to the piston plate 26.

[0080] The driving end of the second motor 5 rotates to drive the rotating disk 16 fixedly connected thereto to rotate. The rotation of the rotating disk 16 drives the eccentric wheel 17 fixedly connected thereto to rotate. The eccentric wheel 17 will make a circular motion around the central axis of the rotating disk 16. The rotation of the eccentric wheel 17 will change the horizontal position of the connecting rod 19, so that the connecting rod 19 makes a reciprocating motion in the horizontal direction, so the connecting rod 19 will drive the slide plate to move, thereby changing the position of the slide plate in the sleeve 18. The movement of the slide plate drives the push rod 15 to move, thereby driving the piston plate 26 to move, thereby achieving the purpose of steam suction and exhaust.

[0081] The heat exchange cylinder 1 is provided with a plugging mechanism 7 which matches with the heat exchange box 12;

[0082] The blocking mechanism 7 includes a partition fixedly mounted on the heat exchange tube 1, the heat exchange tube 1 is divided into two sections by the partition, an intermittent gear ring 21 and a toothed disc 20 meshing with the intermittent gear ring 21 are rotatably mounted on the partition, a first motor 3 is fixedly mounted on the partition, a driving end of the first motor 3 is fixedly connected to the toothed disc 20, and a circular hole matching the heat exchange box 12 is opened on the partition;

[0083] A plurality of incomplete toothed discs 22 are rotatably mounted on the partition, each of which is meshed with the intermittent toothed ring 21 , and a sealing disc 23 matching the circular hole is fixedly mounted on each incomplete toothed disc 22 , and each sealing disc 23 is in contact with the heat exchange box 12 .

[0084] When boosting is performed, the first motor 3 and the second motor 5 operate synchronously. The rotation of the driving end of the first motor 3 drives the gear disc 20 fixedly connected thereto to rotate. The rotation of the gear disc 20 drives the intermittent gear ring 21 meshing therewith to rotate. The rotation of the intermittent gear ring 21 drives the multiple incomplete gear discs 22 meshing therewith to rotate, thereby driving the sealing disc 23 fixedly connected to the incomplete gear disc 22 to rotate. The multiple sealing discs 23 form a closed circular disc for sealing the port of the heat exchange box 12.

[0085] Embodiment 2: This embodiment is different from the embodiment 1 in that: Figure 1-Figure 5 The heat exchange cylinder 1 is provided with a plurality of heat transfer components matched with the corresponding heat exchange boxes 12 .

[0086] The heat transfer component includes a spiral conduit 13 fixedly wound around the outside of the heat exchange box 12. Both ends of the spiral conduit 13 are fixedly connected to a docking conduit 8. A pump box 6 is fixedly installed outside the heat exchange cylinder 1. Both docking conduits 8 extend out of the heat exchange cylinder 1 and are connected to the pump box 6.

[0087] The pump box 6 includes a heat storage device and a circulation device. The heat on the heat exchange box 12 will be absorbed by the heat exchange fluid in the spiral conduit 13, and then enter the pump box 6 through the docking conduit 8;

[0088] The operation of the heat storage device in the pump box 6 can be controlled by a control system to absorb and store the heat of the heat exchange fluid in the docking conduit 8. The heat storage device and the circulation device are both common existing devices and will not be elaborated on here.

[0089] Liquid mercury is stored in the pump box 6 matched with the heat exchange box 12 in the first heat exchange assembly 10, which is mainly used for heat transfer preheating. Liquid mercury has a good heat transfer effect and a high thermal conductivity, which can absorb and conduct the heat on the heat exchange box 12 to a greater extent and reduce heat loss. The outside of the docking conduit 8 is wrapped with a heat insulation film, which is used to keep the docking conduit 8 warm and reduce heat loss during heat conduction.

[0090] The pump box 6 matched with the heat exchange box 12 in the second heat exchange assembly 11 stores high-concentration ethanol for vaporization and pressurization; the pump box 6 matched with the heat exchange box 12 in the third heat exchange assembly stores high-concentration ether for vaporization and pressurization;

[0091] The first heat exchange component 10 is provided to recover the heat in the steam for the first time, and then the second heat exchange component 11 and the third heat exchange component are used to recover the remaining heat in the steam. The steam is dusted during the first recovery, so that the heat is released faster. The multi-stage recovery makes the heat recovery more complete, reduces the loss of heat recovery, and improves the energy utilization rate.

[0092] High-purity ethanol and high-purity ether both have good thermal conductivity, and their boiling points are lower than that of water. Therefore, the heat required to form steam is lower. In this way, steam can be formed under the action of low heat, and then the volume is changed by steam expansion. The steam thermal energy is stored through energy storage equipment and used to release the pressure of aerated concrete in aerated concrete.

[0093] Embodiment 3: This embodiment is different from the technical solution of Embodiment 2 in that: Figure 1-Figure 4 - Figure 12-16 The collecting part includes a smoke hood 4, which is fixedly connected with a steam guide pipe 28. The steam guide pipe 28 is fixedly connected with the heat exchange tube 1. A steam separation component is installed on the steam guide pipe 28. The outside of the steam guide pipe 28 is also wrapped with a thermal insulation film to reduce the heat loss of steam.

[0094] The steam separation assembly includes a steam separation box 30 fixedly mounted inside the steam duct 28, a rotating shaft 33 rotatably mounted on the steam separation box 30, an upper sealing plate 31 abutting against the upper end of the steam separation box 30 is fixedly mounted on the upper portion of the rotating shaft 33, and a lower sealing plate 34 abutting against the lower end of the steam separation box 30 is fixedly mounted on the lower portion of the rotating shaft 33, and a transmission mechanism matching the rotating shaft 33 is mounted on the steam duct 28.

[0095] When the steam enters the hood 4 under the action of its own buoyancy, it will then enter the steam separation box 30, and finally enter the heat exchange tube 1 through the steam separation box 30. If the steam enters the heat exchange tube 1 directly through the steam separation box 30, the heat exchange tube 1 will be connected to the outside world, and the negative pressure generated by the first heat exchange component 10 will suck the outside air into the heat exchange tube 1 through the hood 4. The outside air temperature is lower than the steam temperature, which will absorb the heat on the steam, resulting in reduced steam heat loss. Therefore, when the first heat exchange component 10 sucks the steam into the heat exchange box 12, it is necessary to keep the heat exchange tube 1 isolated from the outside world, which is achieved by using a steam separation component here;

[0096] The steam dividing box 30 divides the steam conduit 28 into three steam inlet bins, and the steam inlet area of ​​each steam inlet bin is the same.

[0097] The rotation of the driving end of the motor 29 will drive the rotating shaft 33 to rotate, thereby driving the upper blocking plate 31 and the lower blocking plate 34 to rotate. The upper blocking plate 31 and the lower blocking plate 34 are both designed in two-thirds of the original design, and are staggered. When rotating, the upper part of one of the steam inlet bins can always be kept connected to the heat exchange cylinder 1, while the bottom is not connected to the smoke hood 4, while the tops of the other two steam inlet bins are not connected to the heat exchange cylinder 1, and the bottoms are connected to the smoke hood 4. When sucking steam, only the steam in the steam inlet bin connected to the heat exchange cylinder 1 will be sucked into the heat exchange box 12;

[0098] It effectively prevents external air from entering the heat exchange tube 1 to cause heat loss, greatly increases the heat retention in the steam, and thus improves the utilization rate of thermal energy.

[0099] The transmission mechanism includes a motor 29 fixedly mounted on the outside of the steam duct 28 , a driving end of the motor 29 extends into the interior of the steam duct 28 , and the driving end of the motor 29 is connected to a rotating shaft 33 via a bevel gear set 32 ​​.

[0100] The rotation of the driving end of the motor 29 will drive the rotating shaft 33 to rotate through the bevel gear set 32, which is used for transmission connection. The longitudinal transmission is converted into a transverse transmission, which can avoid the motor 29 being installed in the steam guide pipe 28, which is beneficial to the smooth passage of steam.

[0101] The specific operation steps of this device are as follows:

[0102] First, the waste heat steam generated by the steel plant will float up under the action of natural buoyancy and enter the steam inlet bin in the smoke hood 4. At this time, the first motor 3, the second motor 5 and the motor 29 are turned on, and the motor 29 drives the upper blocking plate 31 and the lower blocking plate 34 to rotate, so that the steam inlet bin is indirectly connected to the heat exchange cylinder 1;

[0103] The driving end of the second motor 5 rotates to drive the rotating disk 16 fixedly connected thereto to rotate, and the rotating disk 16 rotates to drive the eccentric wheel 17 fixedly connected thereto to rotate. The eccentric wheel 17 will make a circular motion around the central axis of the rotating disk 16. The rotation of the eccentric wheel 17 will change the horizontal position of the connecting rod 19, so that the connecting rod 19 will make a reciprocating motion in the horizontal direction, so the connecting rod 19 will drive the slide plate to move, thereby changing the position of the slide plate in the sleeve 18. The movement of the slide plate drives the push rod 15 to move, thereby driving the piston plate 26 to move;

[0104] When the piston plate 26 moves toward the side close to the heat-conducting cone 24, the space between the heat-conducting cone 24 and the piston plate 26 inside the heat exchange box 12 is compressed, and the space on the other side of the heat exchange box 12 expands, which will draw the steam in the heat exchange cylinder 1 into the heat exchange box 12, which requires the one-way pipe 27 to complete.

[0105] In the heat exchange cylinder 1, the plugging mechanism 7 needs to be kept in operation during steam absorption to plug the ports of the heat exchange box 12. The driving end of the first motor 3 rotates to drive the toothed disc 20 fixedly connected thereto to rotate. The rotation of the toothed disc 20 drives the intermittent toothed ring 21 meshing therewith to rotate. The rotation of the intermittent toothed ring 21 drives the multiple incomplete toothed discs 22 meshing therewith to rotate, thereby driving the plugging disc 23 fixedly connected to the incomplete toothed disc 22 to rotate. The multiple plugging discs 23 form a closed disc to plug the ports of the heat exchange box 12.

[0106] The steam sucked into the first heat exchange component 10 will be pressurized by the booster component, and then contact the heat exchange box 12 in the first heat exchange component 10, and the heat in the steam will be transferred to the heat exchange box 12. The heat on the heat exchange box 12 will be absorbed by the heat exchange liquid in the spiral conduit 13, and then enter the pump box 6 through the docking conduit 8. The control system can be used to control the operation of the heat storage device in the pump box 6, and the heat of the heat exchange liquid in the docking conduit 8 can be absorbed and stored for use in the static curing room. The remaining heat in the steam will be absorbed by the second heat exchange component 11 and the third heat exchange component for use in the steam curing room.

[0107] Embodiment 4: Application of the above waste heat steam collection device in the production of lead-zinc tailings aerated concrete comprises the following steps:

[0108] S1. Preparing concrete slurry: mixing lead-zinc tailings, cement, quicklime and desulfurized gypsum in a mass ratio of 62:24:9:5 to obtain a mixture, adding water, aluminum powder paste and foam stabilizer in mass ratios of 57%, 0.60‰ and 0.256‰ respectively to the mixture, mixing evenly to obtain concrete slurry;

[0109] S2, stirring and foaming;

[0110] S3, pouring test mold;

[0111] S4. Static curing: Place the cast concrete in a static curing room for static curing at 70℃ for 2h;

[0112] S5, demoulding the mold to form a blank;

[0113] S6. Autoclave curing: placing the concrete block in an autoclave curing room for curing at an autoclave pressure of 1.2 MPa and a temperature of 185° C. for 8 hours to obtain a finished aerated concrete product;

[0114] The static curing room and the autoclave curing room are both connected to the heat exchange component of the waste heat steam collecting device through pipelines, and the heat collected by the waste heat steam collecting device is transferred to the static curing room and the autoclave curing room.

[0115] Results Analysis

[0116] 1. The influence of lead-zinc tailings fineness on the performance of aerated concrete

[0117] The lead-zinc tailings, cement, quicklime and desulfurized gypsum (mass percentage) are 60%, 25%, 10% and 5% respectively. The amounts of water, aluminum paste and foam stabilizer are 57%, 0.60‰ and 0.256‰ of the total amount of the four dry materials respectively.

[0118] Mix lead-zinc tailings of different finenesses with quicklime, cement, and desulfurized gypsum, add 50°C warm water and stir for 120s, then add aluminum paste and foam stabilizer and stir for 40s. Pour the stirred slurry into a triple mold (100mm×100mm×100mm), and then keep it at 70°C for 2h. After demoulding, put the formed body into an autoclave for autoclaving. The autoclaving system is: the maximum autoclaving pressure is 1.2MPa, the maximum temperature is 185°C, and the temperature is kept constant for 8h. Aerated concrete products prepared from lead-zinc tailings of different finenesses are obtained, which are numbered Z1, Z2, Z3, Z4, Z5 and Z6.

[0119] The lead-zinc tailings used in production have low activity. If they are to be used as cementitious materials in aerated concrete, they must be activated first. The reaction activation energy of the material is reduced through the mechanochemical effect. Mechanical force reduces the particle size of the raw material particles, increases the specific surface area, and generates a large number of new surfaces, which increases the surface free energy and the reaction activity. When ground siliceous raw materials are added to the product system that has been autoclaved and cured at high temperature, the silicon dioxide in the system has the conditions to participate in the hydration reaction. The ground siliceous raw materials not only play a physical filling role, but also can undergo substantial chemical reactions to generate the main phase of aerated concrete. The grinding fineness of the siliceous raw materials is a key factor in the preparation of aerated concrete. The size of the siliceous raw material particles directly affects the stability of the slurry pouring and the level of the reaction activity of the aerated concrete.

[0120] Fig.17 is the relationship between grinding time and specific surface area, Fig.18 The influence of lead-zinc tailings fineness on the performance of aerated concrete. Fig.18 It can be seen that as the fineness of the lead-zinc tailings decreases, the absolute dry compressive strength of the aerated concrete products increases first and then decreases, while the absolute dry density shows a trend of first decreasing and then increasing. The absolute dry density of the six groups of products is less than 625Kg / m 3 , meeting the requirements of B06. The absolute dry compressive strength of products Z2, Z3, Z4, Z5, and Z6 are all greater than 3.5MPa, meeting the requirements of A3.5, while the compressive strength of product Z1 is 3.38MPa, which does not meet the standard requirements. This shows that the fineness of lead-zinc tailings plays a vital role in the performance of aerated concrete. Like cement and other cementitious materials, increasing the fineness can increase the specific surface area of ​​the tailings in contact with water. The new surface crystals formed are ground and broken, becoming amorphous, which increases the dissolution rate, enhances the ability of the material to participate in chemical reactions, and stimulates the activity of the tailings. The test found that the specific surface area was 405m 2 / kg Z6 product slurry has slight bubbling during pouring, and has high viscosity, and the appearance of the product is poor, which shows that the smaller the fineness of the lead-zinc tailings, the larger the surface area of ​​the particles participating in the reaction, the higher its activity, and the better the slurry fluidity. However, when the fineness is too small, the slurry is too thick, resulting in the inability of the product to form a good pore structure, affecting the performance of the product; the specific surface area is 207m 2 / kg Z1 product casting slurry fluidity is poor, bubbling occurs, indicating that the tailings particles are coarse, the fineness is too large, the slurry fluidity is poor, the sedimentation speed after casting is fast, and it is easy to cause mold collapse and sinking. The test results show that the specific surface area of ​​lead-zinc tailings is 325m 2 / kg, the slurry fluidity and pouring stability are good, the absolute dry density and compressive strength of the product are enhanced to the best, and the aerated concrete product has the best appearance. Therefore, considering the economy and performance, the optimal specific surface area of ​​the tailings in the subsequent test process is determined to be 325m 2 / kg.

[0121] 2. Effect of lead-zinc tailings dosage on the performance of aerated concrete

[0122] By using the lead-zinc tailings with the best fineness, the dosage of lead-zinc tailings was 54%, 56%, 58%, 60%, 62%, 64% and 66%, and the dosage of cement, quicklime and desulfurized gypsum were adjusted accordingly to obtain 7 groups of lead-zinc tailings aerated concrete with different dosages, and the corresponding product numbers are C1, C2, C3, C4, C5, C6 and C7. The dosage of water, aluminum powder paste and foam stabilizer is the same as that of the preparation of lead-zinc tailings aerated concrete with different fineness, and the preparation process is also the same.

[0123] Group Lead-zinc tailings quicklime cement Desulfurization gypsum C1 54 28 12 6 C2 56 26 12 6 C3 58 25 12 5 C4 60 25 10 5 C5 62 23 10 5 C6 64 22 9 5 C7 66 21 8 5

[0124] Fig.19 The figure is the influence curve of different dosages of lead-zinc tailings on the performance of aerated concrete under the same conditions. As can be seen from the figure, with the increase of the dosage of lead-zinc tailings, the absolute dry compressive strength of aerated concrete products generally shows a trend of first increasing and then decreasing, and the absolute dry density first decreasing and then increasing. With the increase of the dosage of lead-zinc tailings, the amount of active SiO2 and Al2O3 dissolved in the system under alkaline conditions increases, the hydration reaction of the system is more complete, the crystal morphology of the hydration product tobermorite is better, and the hydration product is more closely combined with the unreacted particles in the system, so that the compressive strength of the product increases and the absolute dry density decreases. However, when the dosage of lead-zinc tailings is too large, the accumulation of unreacted residual lead-zinc tailings particles in the system increases, the gaps between particles decrease, which is not conducive to the growth and crystallization of hydration products, and the crystallization of hydration products deteriorates, resulting in a decrease in compressive strength and an increase in absolute dry density. When the lead-zinc tailings dosage is 64% and 66%, the excessive iron tailings dosage also reduces the fluidity of the slurry, the initial consistency of the slurry becomes larger, the pore structure in the green body is uneven, the green body expansion height is low, the compressive strength of the product is reduced, and the pore structure in the product is uneven. The C7 product with a tailings dosage of 66% even has a small number of fine cracks vertical to the gas direction on its outer surface, indicating that the tailings dosage under this test condition cannot be greater than 62%. When the lead-zinc tailings dosage is 62%, the absolute dry density of the product is 587kg / m 3 The compressive strength reaches 4.94Mpa. Taking into account the performance of the product and the goal of maximizing the use of lead-zinc tailings and reducing costs, the C5 product with the dosage of lead-zinc tailings, lime, cement and gypsum of 62%, 24%, 9% and 5% respectively is selected as the optimal ratio.

[0125] 3. XRD analysis

[0126] In order to verify the reliability of the C5 formula, X-ray diffraction analysis was used to conduct a preliminary study on the phase composition of lead-zinc tailings and C5 products before and after autoclaving. The test results are as follows: Fig. 20 As shown. Fig. 20 It can be seen from curve 1 that the main mineral components of the lead-zinc tailings used in the experiment are quartz, calcium iron pyroxene, calcium manganese pyroxene, calcite, epidote and diopside. It can be seen from curve 2 that in the green body after hardening without static curing, at room temperature and pressure, after the cast slurry hardened, compared with the physical phase of the lead-zinc tailings, the diffraction peaks of new phases of ettringite (Ettringite) and Ca(OH)2 (Portlandite) appeared, and the XRD diffraction peaks of the main mineral components in the original lead-zinc tailings were reduced; among them, Ca(OH)2 is produced by the hydration reaction of cement and water and the digestion of lime and water. The formation of ettringite is mainly due to two reasons. One is that in the presence of gypsum, the hydrated calcium aluminate (CAH) formed by cement hydration and SO4 in gypsum 2- Combined to form hydrated calcium sulfoaluminate crystals, namely calcium sulfoaluminate (AFt); secondly, under alkaline conditions, a small amount of ultrafine particles in the lead-zinc tailings begin to show chemical reaction activity, and can react with Ca(OH)2 in the slurry to produce corresponding hydration products, such as hydrated calcium silicate (CSH gel) and hydrated calcium aluminate crystals. In the presence of gypsum, the formed hydrated calcium aluminate crystals will quickly form calcium sulfoaluminate crystals, which is also the reason for the decrease of the quartz diffraction peak in curve 2. At the same time, the broad "convex hull" background below the 2θ diffraction peak of 26° to 34° in the curve indicates that there are amorphous (non-diffractive) non-crystalline and extremely low-crystallinity CSH gel in the green body. The calcium sulfoaluminate crystals and CSH gel formed in the green body are also the main sources of the strength of the hardened green body.

[0127] Comparing the two curves 2 and 3, it can be seen that new phases of tobermorite and anhydrite appear in the hardened blank after static curing at 70°C for 2h, the diffraction peak of ettringite disappears, the diffraction peak of Ca(OH)2 decreases, and the diffraction peak of quartz in the lead-zinc tailings further decreases. This is mainly because during the static curing process, with the increase of temperature, the dissolution rate of SiO2 and Al2O3 in the lead-zinc tailings accelerates, and more SiO2 and Al2O3 components react with Ca(OH)2 to generate corresponding hydration products (such as CSH gel and hydrated calcium aluminate crystals). With the increase of SiO2 dissolution, the Ca / Si in the liquid phase decreases, and the double alkaline CSH gel formed in the early stage of cement hydration combines with SiO2 to form low-alkalinity CSH gel and tobermorite. Since ettringite decomposes at higher temperatures, monosulfur hydrated calcium aluminate (AFm), Al 3+ and SO4 2-During the constant temperature stage of static curing, AFm continues to decompose into tricalcium aluminate hexahydrate (C3AH6) and CaSO4. Therefore, there is no characteristic spectrum line of calcium sulfonate in the XRD curve of Curve 3 after static curing at 70℃ for 2h. Due to the addition of gypsum, which has a retarding effect, to the raw material system and the decomposition of AFm after high temperature autoclaving, the diffraction characteristic peak of gypsum is obvious in Curve 3 after static curing.

[0128] In curve 4 after autoclaving, the diffraction peak of Ca(OH)2 disappears, and the diffraction peak of quartz in the lead-zinc tailings is further reduced compared with curve 3, while the diffraction peaks of tobermorite and anhydrite are enhanced. This shows that under the alkaline conditions of high temperature and high pressure, the Si-O bonds and Al-O bonds in the [SiO4] structure of the aerated concrete body in the lead-zinc tailings are broken, which promotes the dissolution rate of SiO2 and Al2O3 in the lead-zinc tailings, and can combine with more Ca(OH)2 to generate corresponding hydration products CSH gel and tobermorite, etc.). The weakening of the quartz characteristic peaks in curves 3 and 4 shows that the amount of tobermorite and CSH gel generated increases, so the diffraction peak of tobermorite in curve 4 after autoclaving tends to increase. Comparing the diffraction peak intensities of pyroxene, pyroxene, calcite, epidote and diopside in curves 2, 3 and 4, there is basically no change, which can explain that these mineral phases basically do not participate in the reaction in the aerated concrete raw material system. The hydration product tobermorite, the residual particles after the reaction of CSH gel and quartz, and pyroxene, pyroxene, calcite, epidote, diopside and anhydrite together constitute the skeleton of the product, so that the aerated concrete product has a sufficiently high strength.

[0129] 4. FT-IR analysis

[0130] Fig.21 The FT-IR spectra of the hardened green body of the C5 sample without static curing, the hardened green body after static curing, and the aerated concrete product after autoclaving for 12 hours are compared. It can be seen from the figure that each absorption peak moves toward the direction of small wave number. In the hardened green body curve 1 without static curing, the strongest absorption area is 1250~1100cm -1 It is the quartz absorption band, which belongs to the Si-O asymmetric stretching vibration, and consists of a weak band at 1160-1250cm -1 And a strong belt 1076~1100cm -1 The absorption bandwidth is wide and strong, among which 1076cm -1 The characteristic peak at is the asymmetric stretching vibration of Si-O, with a wave number of 777 cm -1 There is a moderate absorption peak at 460cm, which belongs to the Si-O-Si symmetric stretching vibration and is a characteristic peak of quartz minerals. -1 The characteristic peak at is attributed to the bending vibration of Si-O

[28] . Wave number at 3650cm -1 The absorption bands on the left and right are attributed to the stretching vibration of the hydroxyl group in Ca(OH)2, with a wave number of 3450cm -1 The characteristic peaks near the hydration product CSH gel or ettringite (AFt) are the stretching vibrations of adsorbed water; the wave number is 1623 cm -1 The absorption bands on the left and right are attributed to the bending vibration of hydroxyl groups adsorbed in water in CSH gel or AFt; the wave number is 1433 cm -1 The absorption band at is attributed to CO3 in calcite 2- Asymmetric stretching vibration, caused by calcite minerals in lead-zinc tailings; wave number at 1000cm -1 ~1050cm -1 The broad bands on the left and right are attributed to the stretching vibration of Si-O bonds, which are caused by the hydration product CSH gel; the wave number is 640cm -1 ~700cm -1 The bands at the bottom characterize the bending vibration of O-Si(Al)-O, which belongs to the vibration bands of pyroxene minerals in lead-zinc tailings.

[0131] Fig.21 The infrared spectra of the aerated concrete product curve 3 after autoclaving are similar to the hardened green body curve 2 after static curing for 2 hours, and there is no significant change. After static curing for 2 hours and high temperature autoclaving, the wave number is 1076cm -1 、1004cm -1 、683cm -1 、645cm -1 and 460cm -1 The characteristic peaks of quartz minerals disappear, and the wave number of quartz in curve 2 is 777 cm -1 The characteristic band of the quartz crystal weakened and disappeared in curve 3. This indicates that with the increase of temperature and pressure, the active SiO2 and Al2O3 in the lead-zinc tailings reacted chemically with Ca(OH)2 to form corresponding hydration products, and the number increased, with a tendency to crystallize. The wave number in curve 3 is 3650cm -1 The characteristic peak of the stretching vibration of the hydroxyl group in Ca(OH)2 disappears, which fully proves this point. -1 The absorption bands attributable to ettringite (AFt) disappear in curves 2 and 3 when the temperature rises, which also indicates that AFt decomposes under high temperature conditions. New characteristic peaks appear on curves 2 and 3, with wave numbers of 1630 cm and 2630 cm, respectively. -1 、978m -1 and 451cm -1 The wave number is 978cm -1The absorption band nearby is the Q 2 The characteristic peak absorption intensity at this position is very strong, which indicates that this vibration has strong infrared activity; the wave number is 451cm -1 The characteristic peaks near are caused by the Si-O bending vibration in the [SiO4] structure. The wave number is 978cm -1 and 451cm -1 The characteristic peaks of 1630cm are all attributed to the layered structure of tobermorite crystal minerals. -1 The absorption band at the position is the bending vibration of H2O.

[0132] 5. FE-SEM analysis

[0133] Fig. 22 , Fig.23 The FE-SEM and EDS spectra of the hardened green body and aerated concrete product of the C5 sample before and after static curing. It can be seen from the green body (a) and (a1) without static curing that the main hydration product is a loose CSH gel with poor crystal structure, which is different from the Fig. 20 The XRD analysis results are consistent. Figure (a1) is an enlarged view of the marked area in Figure (a). The hydration products in the field of view of Figure (a1) are mainly covered by needle-shaped AFt and loose crystalline CSH gel. The CSH gel is located on the right side of the figure. The energy spectrum analysis at the marked area 1 in Figure (a1) shows that its main elements are Ca, S and Al, which are consistent with the composition of AFt. The formation of CSH gel is mainly caused by cement hydration in the raw material system of lead-zinc tailings aerated concrete, and the presence of gypsum in cement raw materials and material systems promotes the formation of AFt. Figures (b) and (b1) are cross-sectional views of the green body after 2 hours of static curing. In the figure, CSH gel with a high degree of crystallization and good crystal shape and a large number of unevenly thick and thin plate-like hydration products can be seen. From the EDS spectrum analysis of area 2 in Figure (b), it can be seen that Al element exists in the hydration product. This is because the lead-zinc tailings contain Al element and aluminum powder paste is added to the raw material system, causing some [SiO4] tetrahedrons to be replaced by [AlO4] tetrahedrons. The hydration product in area 2 has nCa / n(Si+Al)=0.8326, which is basically consistent with the composition of tobermorite. AFt is not seen in the field of view of Figures (b) and (b1), indicating that after the green body is statically cured for 2 hours at 70°C, AFt decomposes under high temperature conditions, which is consistent with the above. Fig. 20 and 5 The XRD and FT-IR analysis are consistent. At the same time, after static curing, the crystallization degree of CSH gel increases, and the formation of a large number of hydration products provides sufficient strength for the green body, providing conditions for the cutting and autoclaving of the green body. Due to the short curing time and low temperature, there are fewer hydration products and the formed structural system is not dense enough.

[0134] Figure (c) shows the hydration product of aerated concrete products after autoclaving for 12 hours. The products are mainly tobermorite and a small amount of CSH gel. In Figure (c1), a large number of plate-like tobermorite crystals are formed after the marked area is enlarged. The thickness is about 0.1-0.2μm. The crystallinity of the plate-like tobermorite is greatly improved. They are intertwined with each other to form the skeleton structure of the aerated concrete products, which gives the products sufficient strength. After high-temperature autoclaving and curing, the solubility of the active components SiO2 and Al2O3 in the lead-zinc tailings increases in the alkaline hydrothermal environment, and the ability to participate in chemical reactions is enhanced, which plays a positive role in improving the crystallinity of the hydration products.

[0135] Using high silicon lead-zinc tailings as the main siliceous raw material, qualified products of A3.5 and B06 grade aerated concrete that meet the national standards can be prepared. Through experimental research, the optimization scheme for preparing aerated concrete with lead-zinc tailings is obtained. The specific surface area of ​​lead-zinc tailings is 325m 2 / kg, the mass ratio of ingredients is: lead-zinc tailings: lime: cement: gypsum = 62:24:9:5, the amount of aluminum paste and foam stabilizer is 0.60‰ and 0.256‰ of the total amount of the four dry materials respectively. The pouring water temperature is 50℃, the static curing temperature is 70℃, and the autoclave curing conditions are: heating for 2h, constant temperature and pressure for 8h (pressure 1.2MPa, temperature 185℃), and cooling for 2h.

[0136] As the fineness of lead-zinc tailings decreases, the slurry pouring stability and the physical and mechanical properties of aerated concrete products are enhanced, but too small a fineness leads to a decrease in the corresponding performance. As the fineness of lead-zinc tailings decreases, the specific surface area of ​​the tailings in contact with water increases, the dissolution rate is increased, the ability of the material to participate in chemical reactions is enhanced, the activity of the tailings is stimulated, and the strength of the product is improved; however, if the fineness is too small, the slurry is too thick, resulting in the product being unable to form a good pore structure, affecting the performance of the product.

[0137] With the increase of lead-zinc tailings dosage, the amount of active SiO2 and Al2O3 dissolved in the system under alkaline conditions increases, the hydration reaction of the system is more complete, and the physical and mechanical properties of aerated concrete products are enhanced. However, if the lead-zinc tailings dosage is too large, the accumulation of unreacted residual tailings particles in the system increases, the gaps between particles decrease, which is not conducive to the growth and crystallization of hydration products, resulting in performance degradation.

[0138] The application of waste heat steam collection equipment from steel plants in the production of lead-zinc tailings aerated concrete has greatly reduced the energy consumption of aerated concrete production and has great economic benefits.

[0139] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A waste heat steam collection device for a steel plant, comprising a heat exchange part, characterized in that: It also includes the collection department; The heat exchange part comprises a heat exchange cylinder (1), a heat insulation inner cylinder (9) is fixedly installed inside the heat exchange cylinder (1), and a first heat exchange component (10), a second heat exchange component (11) and a third heat exchange component are fixedly installed inside the heat insulation inner cylinder (9); The first heat exchange assembly (10), the second heat exchange assembly (11) and the third heat exchange assembly all comprise a heat exchange box (12) and a heat-conducting cone (24) fixedly mounted inside the heat exchange box (12); the outside of each heat exchange box (12) is fixedly connected to a flow guide hopper (14); a booster assembly is installed between the heat exchange box (12) and the heat exchange cylinder (1) in the first heat exchange assembly (10); and a plurality of heat transfer assemblies matching the corresponding heat exchange boxes (12) are installed on the heat exchange cylinder (1); The collecting part comprises a smoke hood (4), a steam guide pipe (28) is fixedly connected to the smoke hood (4), the steam guide pipe (28) is fixedly connected to the heat exchange cylinder (1), and a steam separation component is installed on the steam guide pipe (28).

2. The waste heat steam collection equipment for a steel plant according to claim 1, characterized in that: A swirl blade (25) is fixedly installed in each heat exchange box (12), and the heat conduction cones (24) in each heat exchange box (12) are arranged in a staggered manner.

3. The waste heat steam collection equipment for a steel plant according to claim 1, characterized in that: The booster assembly comprises a piston plate (26) slidably mounted inside a heat exchange box (12); a plurality of through holes are provided on the piston plate (26) and the heat exchange box (12); a one-way tube (27) is fixedly mounted in each of the through holes; a driving mechanism matched with the piston plate (26) is mounted on the heat exchange cylinder (1); and a sealing mechanism (7) matched with the heat exchange box (12) is mounted on the heat exchange cylinder (1).

4. The waste heat steam collection equipment for a steel plant according to claim 3, characterized in that: The driving mechanism comprises a frame fixedly mounted on the outside of the heat exchange cylinder (1), a second motor (5) fixedly mounted on the frame, a rotating disk (16) fixedly mounted on the driving end of the second motor (5), an eccentric wheel (17) fixedly mounted on the rotating disk (16), a connecting rod (19) rotatably mounted on the eccentric wheel (17), a sleeve (18) fixedly mounted on the frame, a slide plate slidably mounted in the sleeve (18), the slide plate and the connecting rod (19) are rotatably connected, a push rod (15) fixedly mounted on one end of the slide plate away from the connecting rod (19), the push rod (15) passes through the heat exchange cylinder (1) and is fixedly connected to the piston plate (26).

5. The waste heat steam collection equipment for a steel plant according to claim 3, characterized in that: The blocking mechanism (7) comprises a partition fixedly mounted on the heat exchange tube (1), the heat exchange tube (1) being divided into two sections by the partition, an intermittent gear ring (21) and a toothed disc (20) meshing with the intermittent gear ring (21) being rotatably mounted on the partition, a first motor (3) being fixedly mounted on the partition, a driving end of the first motor (3) being fixedly connected to the toothed disc (20), and a circular hole matching the heat exchange box (12) being provided on the partition; A plurality of incomplete toothed discs (22) are rotatably mounted on the partition, each of the incomplete toothed discs (22) is meshed with the intermittent toothed ring (21), and a sealing disc (23) matching the circular hole is fixedly mounted on each of the incomplete toothed discs (22), and each of the sealing discs (23) is in contact with the heat exchange box (12).

6. The waste heat steam collection equipment for a steel plant according to claim 1, characterized in that: The heat transfer component comprises a spiral conduit (13) fixedly wound around the outside of a heat exchange box (12), both ends of the spiral conduit (13) being fixedly connected to a docking conduit (8), a pump box (6) being fixedly mounted on the outside of the heat exchange cylinder (1), and both docking conduits (8) extending out of the heat exchange cylinder (1) and connected to the pump box (6).

7. The waste heat steam collection equipment for a steel plant according to claim 1, characterized in that: Liquid mercury is stored in the pump box (6) matched with the heat exchange box (12) in the first heat exchange component (10), and is mainly used for heat transfer preheating; high-concentration ethanol is stored in the pump box (6) matched with the heat exchange box (12) in the second heat exchange component (11), and is used for vaporization and pressurization; high-concentration ether is stored in the pump box (6) matched with the heat exchange box (12) in the third heat exchange component, and is used for vaporization and pressurization.

8. The waste heat steam collection equipment for a steel plant according to claim 1, characterized in that: The steam separation assembly comprises a steam separation box (30) fixedly mounted inside the steam guide pipe (28); a rotating shaft (33) is rotatably mounted on the steam separation box (30); an upper sealing plate (31) abutting against the upper end of the steam separation box (30) is fixedly mounted on the upper part of the rotating shaft (33); and a lower sealing plate (34) abutting against the lower end of the steam separation box (30) is fixedly mounted on the lower part of the rotating shaft (33); a transmission mechanism matched with the rotating shaft (33) is mounted on the steam guide pipe (28); the transmission mechanism comprises a motor (29) fixedly mounted outside the steam guide pipe (28); a driving end of the motor (29) extends into the interior of the steam guide pipe (28); and the driving end of the motor (29) is connected to the rotating shaft (33) via a bevel gear set (32).

9. Use of the waste heat steam collection equipment of a steel plant according to any one of claims 1 to 9 in the production of autoclaved building materials.

10. The use of the waste heat steam collection device of a steel plant in the production of autoclaved building materials according to claim 9, including the use of the waste heat steam collection device in the production of lead-zinc tailings aerated concrete, comprising the following steps: S1. Preparing concrete slurry: mixing lead-zinc tailings, cement, quicklime and desulfurized gypsum in a mass ratio of 62:24:9:5 to obtain a mixture, adding water, aluminum powder paste and foam stabilizer in mass ratios of 57%, 0.60‰ and 0.256‰ respectively to the mixture, mixing evenly to obtain concrete slurry; S2, stirring and foaming; S3, pouring test mold; S4. Static curing: Place the cast concrete in a static curing room for static curing at 70℃ for 2h; S5, demoulding the mold to form a blank; S6. Autoclave curing: placing the concrete block in an autoclave curing room for curing, the autoclave pressure is 1.2 MPa, the temperature is 185°C, the temperature is kept constant for 8 hours, and the temperature is lowered to obtain the finished aerated concrete product; The static curing room and the autoclave curing room are both connected to the heat exchange component of the waste heat steam collecting device through pipelines, and the heat collected by the waste heat steam collecting device is transferred to the static curing room and the autoclave curing room.

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