System and method for recovering waste heat for high-temperature solid slag particles

Abstract

FIELD: waste heat recovery.SUBSTANCE: group of inventions relates to the technology of recovery of waste heat from solid particles of high-temperature slag. The system comprises a granulation device, a rotating recuperative heat exchanger and waste heat recovery equipment. The granulating device is a gas-cooled granulating device, a gas-water granulating device, or a rotary bowl granulating device. The rotating recuperative heat exchanger comprises an inlet for slag particles corresponding to a slag outlet of the granulation device, an outlet for slag particles and a set of heat exchange tubes located inside the recuperative heat exchanger. The set of heat exchange tubes has a cooling medium inlet and a cooling medium outlet, and the cooling medium is preferably water. The cooling medium inlet and the cooling medium outlet are respectively connected to the waste heat recovery equipment via pipelines. The waste heat recovery equipment comprises a steam drum comprising a steam drum water inlet, a steam drum steam outlet, a saturated steam outlet and a steam-water mixture inlet, and a water tank. The steam drum water inlet is connected to the water tank, the cooling medium inlet is connected to the steam drum water outlet, and the cooling medium outlet is connected to the steam-water mixture inlet.EFFECT: high efficiency of heat exchange and high efficiency of heat recovery of high-temperature solid slag particles.26 cl, 26 dwg, 11 ex

Description

[0001] Field of technology to which the invention relates

[0002] The invention relates to heat recovery technology, in particular to a system and method for recovering waste heat for high-temperature solid slag particles.

[0003] Technology Level

[0004] In the context of modern social development, the steel industry is a fundamental industry in China, ensuring economic development and building major sources of income. However, it also makes a major contribution to energy consumption and pollutant emissions. Research has found that waste heat resources in the steel industry account for 60% of the total energy consumption of the steel industry, and these resources are mainly stored in products, blast furnace slag, production waste, and metal-containing slag. In China, the temperature of blast furnace slag discharged from the furnace is 1400-1550℃, and each ton of slag contains (1260-1880) × 10 6J of specific heat, which is equivalent to the thermal equivalent of 60 kg of standard coal. After granulation, its temperature remains at least 200-900°C, preferably 300-800°C. Therefore, research and development in slag waste heat recovery technology is of great importance for energy conservation and emission reduction in the steel industry.

[0005] The heat exchange process of high-temperature slag waste heat recovery technology mainly includes the following: the granulation process of high-temperature molten slag, the waste heat recovery process of high-temperature slag particles after granulation, and the treatment process of the cooling medium after heat recovery. Methods for recovering heat from high-temperature slag particles include gas-solid direct contact heat exchange, liquid-solid direct contact heat exchange, and so on. Cooling media include water, air, and so on. However, the research and development of large-volume slag processing is insufficient, and thermal energy loss still remains a problem.

[0006] Disclosure of invention

[0007] In view of the above-mentioned technical problems, the object of the present invention is to provide a system for recovering waste heat of high-temperature slag particles, and the heat transfer process thereof comprises the following: direct contact heat exchange between air and slag particles and indirect contact heat exchange between water / steam and slag particles, improving the efficiency of heat recovery of high-temperature solid slag particles.

[0008] The technical solution for achieving the above-mentioned object according to the present invention is as follows:

[0009] Waste heat recovery system for high temperature solid slag particles, comprising:

[0010] a granulating device, wherein the granulating device is preferably a gas-cooled granulating device, a gas-water granulating device, or a rotary bowl granulating device;

[0011] a rotating recuperative heat exchanger, wherein the recuperative heat exchanger comprises an inlet for slag particles corresponding to the slag outlet of the granulating device, an outlet for slag particles and a set of heat exchange tubes located inside the recuperative heat exchanger, wherein the set of heat exchange tubes has an inlet for a cooling medium and an outlet for a cooling medium, and the cooling medium is preferably water; and

[0012] a waste heat recovery equipment, wherein the cooling medium inlet and the cooling medium outlet are respectively connected to the waste heat recovery equipment through pipelines.

[0013] Heat recovery equipment is used to save the heat recovered from high-temperature slag particles and further use it according to subsequent installations.

[0014] Preferably, the waste heat recovery equipment comprises:

[0015] a steam drum, wherein the steam drum comprises a steam drum water inlet, a steam drum steam outlet, a saturated steam outlet, and a steam-water mixture inlet;

[0016] water tank;

[0017] wherein the water inlet of the steam drum is connected to the water tank, the cooling medium inlet is connected to the steam outlet of the steam drum, and the cooling medium outlet is connected to the steam-water mixture inlet.

[0018] The piping system separates saturated water and saturated steam in the steam drum. The saturated steam (approximately 180℃) can then be used by downstream consumers, such as heating buildings or low-pressure boilers. A water tank is used to replenish the water volume in the steam drum, ensuring that the water level in the steam drum remains constant after the steam is released.

[0019] Preferably, the waste heat recovery system for high-temperature solid slag particles also includes a conveyor and a dust collector located below the slag particle outlet, wherein the inlet end of the dust collector is connected to the air outlet of the recuperative heat exchanger through a pipeline, and the outlet of the dust collector is connected to the waste heat recovery equipment through a pipeline.

[0020] After the slag particles undergo heat exchange through a set of heat exchange tubes, the additional heat of the slag particles can also be transferred to the waste heat recovery equipment through a pipeline. Preferably, the heat exchanger comprises a cylinder, wherein the slag particle inlet and the slag particle outlet are respectively located at the upper end and bottom of the cylinder, an air outlet is provided at the upper part of one side wall of the cylinder, and an air inlet pipeline and a fan are provided at the lower part of the other side wall; it is preferable that a guide plate that guides a uniform flow of slag particles is located at the upper part of the cylinder; it is preferable that the lower part of the cylinder is equipped with air distribution equipment.

[0021] By using air distribution equipment, it is possible to accelerate the heat dissemination from slag particles through the pipeline and speed up the heat transfer process to the waste heat recovery equipment.

[0022] Preferably, the heat exchanger comprises a cylinder formed in the form of a metal shell-and-tube structure, and an inlet for slag particles and an outlet for slag particles are respectively located on the side wall of the cylinder on the outlet side for the cooling medium and on the side wall of the cylinder on the inlet side for the cooling medium, wherein spiral plates with interconnected through holes into which heat exchange tubes are inserted are located inside the cylinder; preferably, the outer shell of the cylinder has a water-cooled wall structure containing a cylinder heat exchange tube liner, a central heat exchange tube, a spiral plate located inside the cylinder, and a set of heat exchange tubes passing through the spiral plates.

[0023] The use of a heat exchange device with spiral plates similar to a rotating body can achieve rapid cooling (at least 20℃ / min) of high-temperature slag particles while simultaneously releasing saturated steam.

[0024] Preferably, the heat exchanger is a metal shell and tube structure, the internal structure of which is vertically divided from top to bottom into a superheat section and an evaporator section, wherein the first set of heat exchange tubes and the second set of heat exchange tubes are respectively located in the superheat section and the evaporator section, wherein the inlet end of the first set of heat exchange tubes is connected to the outlet for saturated steam of the steam drum, and the outlet end of the first set of heat exchange tubes is connected to the steam pipe network by a pipeline through a buffer tank, the inlet end of the second set of heat exchange tubes is connected to the outlet for saturated water of the steam drum, and the outlet end of the second set of heat exchange tubes is connected to the inlet for saturated steam-water mixture of the steam drum, the heat exchanger is provided with guide plates arranged vertically at intervals, and a trough for distributing the material is located under the inlet for the slag material,and through holes are made on the guide plates for the passage of heat exchange tubes.

[0025] The guide plates effectively support the heat exchange tube set and prevent slag particle flow deviation, ensuring a uniform and consistent slag particle flow in all areas. The material distribution chute can rotate 360 ​​degrees and tilt up and down within a range of 0-90 degrees (0 degrees corresponds to horizontal placement, and 90 degrees corresponds to vertical placement). When distributing material, the chute can evenly distribute high-temperature slag particles through rotation and tilting.

[0026] Preferably, the waste heat recovery system for high-temperature solid slag particles also includes a disturbance rod inserted between the first heat exchange tube and the second heat exchange tube in the heat exchanger, wherein one end of the disturbance rod is fixed to the fixed base, and the other end of the disturbance rod protrudes beyond the heat exchanger; the disturbance arms are arranged at intervals in the axial direction on the body of the disturbance rod, and the axis of the disturbance arm and the axis of the disturbance rod form an angle; it is preferable that adjacent disturbance arms are installed antisymmetrically;

[0027] a drive device whose output end is connected to the end of a disturbing rod protruding beyond the heat exchanger.

[0028] Through the action of the excitation rod and its excitation levers, it is possible to prevent slag particles from clogging between the heat exchange tubes.

[0029] It is preferable that the drive device be in the form of a worm and a worm wheel, wherein the worm wheel is coaxially connected to the end of the exciting rod.

[0030] Preferably, the waste heat recovery system for high-temperature solid slag particles also comprises at least one high-temperature tank located between the granulating device and the recuperative heat exchanger, wherein the inlet connected to the slag outlet of the granulating device is located on the upper part of the high-temperature tank, and the outlet connected to the slag particle inlet of the heat exchanger is located at the lower part of the high-temperature tank; the lower part of one side wall of the high-temperature tank is provided with an air inlet, an air pipeline and a fan, while the upper part of the opposite side wall is provided with an air outlet that is connected to the inlet end of the dust collector through a pipeline, the outlet of the dust collector is connected through a pipeline to the waste heat recovery equipment;It is preferable that a temperature detection device be installed in the pipeline connected to the dust collector; it is preferable that an air distribution equipment connected to the air pipeline be located at the lower part of the high-temperature tank; it is more preferable that a filter mesh, an insulating material and an outer shell are located on the side wall of the high-temperature tank from the inside to the outside.

[0031] The high temperature tank serves as a link between molten slag granulation and slag particle heat exchange, facilitating the control of molten slag generated at different power levels without loss, and achieving flexible control of the recuperative heat exchanger.

[0032] To prevent the agglomeration of solid slag particles in the high-temperature tank, it is necessary to cool the slag particles in the high-temperature tank. The fan power can be adjusted using a temperature detection device. Hot air discharged from the high-temperature tank is cleaned by a dust collector and directed to waste heat recovery equipment. It then enters the air cleaner through a fan for cleaning, and is discharged after meeting emission standards.

[0033] Preferably, the waste heat recovery equipment also comprises a superheater and / or an evaporator, wherein the inlet of the superheater is connected to the saturated steam outlet of the steam drum, and the outlet of the superheater is connected to the steam pipe network; the inlet of the evaporator is connected to the water tank, and the outlet of the evaporator is connected to the water inlet of the steam drum.

[0034] The superheater can further heat the saturated steam exiting the steam drum, converting it into superheated steam (around 220℃) for use in steam pipe networks, such as power plants. At this time, the heat source for converting the saturated steam into superheated steam can be hot air blown by the aforementioned high-temperature tank or the air distribution equipment of the heat exchanger. At the same time, after the saturated steam is converted into superheated steam, the heat source can further preheat the water from the water tank in the evaporator. The preheated water from the evaporator then enters the steam drum. It is preferable for the hot air to first pass through the superheater and then sequentially through the evaporator to maximize the utilization of heat in converting saturated steam into superheated steam.

[0035] Preferably, the superheater and the evaporator are arranged in a sealed container, and the air inlet is located on the sealed container and connected to the outlet of the dust collector through a pipeline; the outlet of the sealed container is connected to the air purifier through a pipeline and a fan; it is preferable that the evaporator and the superheater have a spiral structure; it is preferable that a water purification device is additionally installed between the evaporator and the water tank.

[0036] The water purification device is used to remove oxygen and desalinate water.

[0037] Preferably, the gas-cooled granulating device comprises:

[0038] a granulation chamber having a box-shaped structure, in which an inlet for a molten slag flow is located at the upper part of the granulation chamber, and a trough for a molten slag flow is located above the inlet for a molten slag flow; an outlet for a flow of slag particles is located at the lower part of the granulation chamber;

[0039] a high-pressure nozzle located on the side wall of the granulating chamber, wherein the outlet of the high-pressure nozzle faces the inlet for the molten slag flow, and the air outlet, dust collector and fan are located at the upper part of the other side wall of the granulating chamber; preferably, the high-pressure nozzle is a Laval nozzle.

[0040] High pressure air impact and granulation is a kind of dry granulation and will not produce wastewater or polluting gases.

[0041] Preferably, the gas-water granulation device comprises:

[0042] a granulation chamber having a box-shaped structure, in which an inlet for a flow of molten slag is located at the upper part of the granulation chamber, and a trough for a flow of molten slag is located above the inlet for a flow of molten slag; an outlet for a flow of slag particles is located at the lower part of the granulation chamber;

[0043] a high-pressure nozzle located on the side wall of the granulating chamber, wherein the outlet of the high-pressure nozzle faces the inlet for the molten slag flow, and the outlet for the gas-water mixture, the gas-water separator and the fan are located at the upper part of the other side wall of the granulating chamber, wherein the high-pressure nozzle is a spray nozzle or a gas-liquid dual-flow nozzle.

[0044] The gas-water mixture ratio can be adjusted by the compressed air flow regulating valve and the water flow regulating valve.

[0045] Preferably, the rotary bowl granulating device comprises:

[0046] a granulation chamber having a box-shaped structure, in which an inlet for a molten slag flow is located at the upper portion of the granulation chamber, and an outlet for molten slag particles is located at the lower portion, an air inlet, an air supply pipe and a fan are located at the lower portion of one side wall of the granulation chamber, and an air outlet, an air discharge pipe, a dust collector and a fan are located at the upper portion of the other side wall of the granulation chamber;

[0047] rotating motor located in the center of the granulating chamber;

[0048] rotary bowl located at the output end of the rotating motor.

[0049] The heat exchanger preferably contains:

[0050] a drum cylinder, wherein the slag particle inlet is located on the side wall of the drum cylinder near the cooling medium outlet, and the slag particle outlet is located near the cooling medium inlet on the side wall of the drum cylinder; the drum cylinder is installed at an inclination downward, toward the cooling medium outlet, which allows the slag particles to move from the slag particle inlet to the slag particle outlet; preferably, the drum cylinder consists of an inner cylinder, an outer cylinder and an insulating material between the inner and outer cylinders;

[0051] a plurality of lifting plates arranged at intervals on the inner wall of the drum cylinder along the circumference of the inner wall of the drum cylinder, wherein the lifting plates are L-shaped;

[0052] a cylinder drive device comprising a toothed ring, a drive motor and a support structure located outside the drum cylinder, wherein the cylinder drive device is used to rotate the drum cylinder, and

[0053] The heat exchange tubes are located in the center of the drum cylinder, on the inner wall of the drum cylinder and on the inner side of the lifting plates.

[0054] The main function of the lifting plate is to disperse high-temperature slag particles. The length and angle of the lifting plates are determined based on the flow rate of the high-temperature slag particles being processed.

[0055] Preferably, the heat exchange tube set comprises a type A heat exchange tube set and a type B heat exchange tube set, a plurality of fins are vertically arranged around the circumference on the outer wall of the type A heat exchange tube set to form a finned tube, the type A heat exchange tube set is located in the center of the drum cylinder, and the fins are preferably ring fins, columnar fins or plate fins; the type B heat exchange tube set is located on the lifting plates or on the inner wall of the drum cylinder.

[0056] When the lifting plates disperse the high-temperature slag particles, the type B heat exchange tube cools the high-temperature slag particles inside the lifting plates. Fins (ring fins, columnar fins, plate fins, etc.) are welded to the outside of the type A heat exchange tube to improve heat exchange between the high-temperature slag particles and the tube wall; it is preferable to use ring fins to improve heat exchange.

[0057] High-temperature slag particles are dispersed by lifting plates in the drum cylinder and simultaneously exchange heat with the lifting plates and heat exchange tubes on the drum wall. The dispersed high-temperature slag particles come into contact with finned heat exchange tubes in the center of the drum, thereby cooling them. The drum cylinder is installed at an angle; as it rotates, the high-temperature slag particles gradually move toward the drum outlet, achieving heat exchange.

[0058] It is preferable that the heat exchange tube set be arranged in a drum cylinder with multiple tube passes, and the number of tube passes is odd; it is preferable that the flow resistance of each heat exchange tube be the same, so as to ensure that the flow of the cooling medium is not deviated.

[0059] Preferably, the waste heat recovery system for high temperature solid slag particles also comprises:

[0060] a buffer tank drum having an inlet and an inlet pipe on one side of its side wall and an outlet and an outlet pipe on the other side; the buffer tank drum is installed at an inclination toward the outlet side, which ensures that slag particles move from the inlet end to the outlet end inside the cylinder;

[0061] The first material lifting plates, which are arranged vertically at intervals along the inner wall of the buffer tank drum around the circumference and have an L-shape;

[0062] a first drive device comprising a toothed ring, a first drive motor and a corresponding support structure located on the outer wall of the drum of the buffer tank.

[0063] Preferably, the heat exchanger contains:

[0064] a drum cylinder which is arranged horizontally, and at the ends of the drum cylinder there are provided a feeding device containing an inlet for slag particles, and an outlet device containing an outlet for slag particles;

[0065] a material guide spiral plate located inside the drum cylinder, in which through holes are made for the passage of a set of heat exchange tubes;

[0066] a supporting roller device located at the lower part of the cylinder near the end of the cylinder on which the discharge device is located, corresponding to the outer annular surface of the drum cylinder; the supporting roller device is located at the lower part of the cylinder, coinciding with the outer annular surface of the drum cylinder, and is used to support the drum cylinder;

[0067] A holding roller device located at the lower part of the cylinder near the end of the cylinder on which the feed device corresponding to the side surface of the drum cylinder is located; the holding roller device is used to stabilize the inclined drum cylinder, ensuring stable rotation;

[0068] a transmission device disposed on a supporting roller device; the drum cylinder is supported by the supporting roller device and the holding roller device, and it can perform a continuous rotary motion driven by the transmission device; wherein

[0069] A set of heat exchange tubes are evenly distributed inside the drum cylinder.

[0070] It takes about 40 minutes for the slag particles to move from the inlet end of the heat exchanger to the outlet end, and the temperature drops from 750℃ to 200℃ or less.

[0071] Preferably, the waste heat recovery system for high temperature solid slag particles satisfies one or more of the following items:

[0072] The cylinder is composed of three sections, which are respectively made of heat-resistant stainless steel, stainless steel and alloy steel, sequentially forming a high-temperature section, a medium-temperature section and a low-temperature section;

[0073] The transmission device consists of a main transmission system and an auxiliary transmission system, which are mutually self-locking, and the main motor of the main transmission system uses a variable speed motor;

[0074] The length of the spiral plate guiding the material protruding beyond the cylinder is 100-200mm.

[0075] The drum cylinder is composed of three sections, which are respectively made of heat-resistant stainless steel, stainless steel and alloy steel, and the cylinder is divided into a high-temperature section (750℃-550℃), a medium-temperature section (550℃-350℃) and a low-temperature section (less than 350℃); According to the requirements of the temperature change of the heat exchanger sections, the temperature can be reduced from 750℃ to 200℃ or lower, and the production costs can be reduced by using different materials.

[0076] The transmission device consists of a main transmission system and an auxiliary transmission system, which are mutually self-locking (when the main transmission system is activated, the auxiliary transmission system cannot be activated, and vice versa). The main motor of the main transmission system uses a variable-speed motor, which can adjust the rotation speed of the drum cylinder according to the operating requirements of the heat exchanger. When the drum cylinder is under maintenance or the main motor is turned off, the auxiliary transmission system is turned on.

[0077] The heat exchanger preferably contains:

[0078] a heat exchanger cylinder provided with a feed box containing an inlet for slag particles and a discharge box containing an outlet for slag particles at the ends of the heat exchanger cylinder, wherein the ends of the heat exchanger cylinder near the discharge box and the feed box are respectively provided with a water collector and a steam-water collector;

[0079] Dual support and holding roller devices located on both sides of the heat exchanger cylinder;

[0080] rotary drive device located at the bottom of the middle part of the heat exchanger cylinder; and

[0081] The steam drum and heat exchanger form a closed circulation system;

[0082] The waste heat recovery equipment comprises a superheater, which is equipped with a preheating module, a superheating module and a combustion module in sequence from top to bottom; the steam drum is connected to the preheating module through a water inlet pipe and to the superheating module through a steam outlet pipe;

[0083] The blowdown pipe and the emergency water discharge pipe are located at the bottom of the steam drum, and the blowdown pipe and the emergency water discharge pipe are connected to the blowdown expansion tank;

[0084] The control valve, preferably an electric control valve, is located on the inlet pipe of the water tank, and the outlet pipe of the water tank is connected to the inlet of the water feed pump, the outlet pipe of the water feed pump is connected to the inlet of the superheater; it is preferable that the water tank is equipped with a liquid level sensor.

[0085] It is preferable that the heat exchanger meet one or more of the following requirements:

[0086] Continuous spiral tube support plates are welded to the inner wall of the heat exchanger cylinder. The continuous spiral tube support plates are spirally distributed along the axis inside the heat exchanger cylinder. Corresponding through holes are formed on the spiral tube support plates, and a set of heat exchange tubes is inserted into the through holes of the spiral tube support plates. Both ends of the heat exchanger cylinder are provided with flanged tube plates, and the ends of the heat exchange tube are respectively fixed on two flanged tube plates, which are fixedly connected to the steam-water collector and the water collector, respectively. One end of the heat exchange tube is connected to the water collector, and the other end of the heat exchange tube is connected to the steam-water collector.The water manifold is rotatably connected to a rotary joint for water inlet, and the steam-water manifold is rotatably connected to a rotary joint for steam outlet, with graphite used to seal the rotary joint. The steam-water manifold and water manifold rotate together with the heat exchanger cylinder.

[0087] The heat exchanger cylinder is equipped with an inner cylinder wall and an outer cylinder wall. The inner cylinder wall and heat exchange tube form a heat exchange space, and an insulating material is placed between the inner and outer cylinder walls. End plates are located on the inner and outer cylinder walls and ends, and discharge scrapers are welded circumferentially between the end plates and the flanged tube plate on the discharge side.

[0088] Preferably, the superheater is equipped with a preheating module, a superheating module and a combustion module in sequence from top to bottom;

[0089] The combustion module contains a furnace, a burner, an exhaust gas circulation pipeline and a circulation fan;

[0090] The superheating module contains a steam inlet, a steam inlet manifold, a steam outlet manifold, a steam outlet and a set of superheating tubes;

[0091] The steam discharge pipe of the steam drum is connected to the steam inlet of the superheating module, and the saturated steam from the steam drum is supplied to the steam inlet header through the steam inlet of the superheating module, and the saturated steam is uniformly distributed over the set of superheating tubes through the steam inlet header;

[0092] The superheating module comprises a water inlet, a water inlet manifold, a water outlet manifold, a water outlet, and a set of preheating pipes; the outlet pipe of the water supply pump is connected to the water inlet, and the cold water from the water tank is fed into the water inlet manifold through the water inlet, and the cold water is evenly distributed among the set of preheating pipes through the water inlet manifold; the exhaust gas after heat exchange in the superheating module passes upward through the preheating module, heating the cold water in the set of preheating pipes, after being collected by the water outlet manifold on the preheating module, the water outlet on the water outlet manifold is connected to the water inlet pipe of the steam drum, and the hot water is supplied to the steam drum.

[0093] The present invention provides a method for recovering waste heat for high-temperature solid slag particles, the method including the following steps:

[0094] a) introducing molten slag into a granulation device to granulate molten slag to obtain slag particles, and air during the granulation process of molten slag carries out contact heat exchange with the molten slag and is discharged through a dust collector and a fan; preferably, gas-cooled granulation, gas-water granulation or rotary bowl granulation are used to granulate the molten slag;

[0095] b) introducing slag particles into a recuperative heat exchanger, where the slag particles carry out indirect contact heat exchange with water or steam from the steam drum through a set of heat exchange tubes, and the water or steam absorbs heat and then returns to the steam drum and / or superheater and evaporator;

[0096] c) send the slag particles after heat exchange to the outside via conveyor.

[0097] Preferably, in step b), the slag particles fall uniformly under the action of the guide plates of the recuperative heat exchanger, and in the process of falling, they exchange heat with the air blown out by the air distribution equipment located at the lower part of the recuperative heat exchanger.

[0098] Preferably, in step b), the slag particles undergo indirect contact heat exchange with water or steam from the steam drum through a set of heat exchange tubes and / or a cylinder heat exchange tube liner and / or a central heat exchange tube, wherein the slag particles subjected to heat exchange are pushed along the spiral plate onto the conveyor and discharged through the conveyor.

[0099] Preferably, in step b), the saturated water from the steam drum enters the second heat exchange tube in the evaporator section of the recuperative heat exchanger, after heat exchange with high-temperature slag particles, it turns into a saturated mixture of water and steam, which is then returned to the steam drum through a steam-water separation pipe; the saturated steam from the steam drum enters the first heat exchange tube of the superheat section of the recuperative heat exchanger under the action of pressure difference, and after heat exchange with the slag particles, it forms superheated steam, which then passes through the pipe to the steam pipe network through the buffer tank; preferably, if the slag flow rate is lower than a set value, the steam pipe in the superheat section is closed.

[0100] Preferably, before step b), the slag particles first enter the high-temperature storage tank for temporary storage, and then enter the recuperative heat exchanger; during the temporary storage of slag particles in the high-temperature tank, the hot air generated in the high-temperature tank is sent to the waste heat recovery equipment for heat exchange after dust is removed by the dust collector; it is preferable to use multiple high-temperature tanks arranged in parallel.

[0101] The advantages of the present invention are:

[0102] 1. The present invention enables large-scale recovery of heat generated by high-temperature slag particles, using mainly water as the heat recovery medium. During the evaporation of water, a large amount of latent heat is absorbed, and the convection and boiling heat transfer coefficients between water and the metal pipe walls are very high (the heat flux density is about 105 W / m 2 ), which increases the efficiency of waste heat recovery. 2. The present invention eliminates heat loss through the intermediate heat-transfer medium by directly exchanging high-temperature slag particles, a set of heat exchange tubes, and a cooling medium (water). The flow and heat exchange of high-temperature slag particles outside the heat exchange tube results in heat transfer to the water or steam inside the heat exchange tube, resulting in the formation of superheated steam. At the same time, cold or saturated water can further utilize the remaining waste heat, thereby achieving maximum heat recovery from the high-temperature slag particles.

[0104] Brief description of drawings

[0105] Fig. 1 is a schematic diagram of a slag particle waste heat recovery system according to an example of the present invention.

[0106] Fig. 2 is a schematic diagram of a slag particle waste heat recovery system according to another example of the present invention;

[0107] Fig. 3 is a schematic diagram of a slag particle waste heat recovery system according to another example of the present invention;

[0108] Fig. 4 is a schematic diagram of the internal structure of a heat exchanger according to an example of the present invention.

[0109] Fig. 5 is a schematic diagram of a slag particle waste heat recovery system according to a modified embodiment of the present invention;

[0110] Fig. 6 is a schematic diagram of a slag particle waste heat recovery system according to another modified embodiment of the present invention;

[0111] Fig. 7 is a schematic diagram of a high-temperature tank according to the present invention.

[0112] Fig. 8 is a schematic diagram of the structure and process of another granulating apparatus according to the present invention.

[0113] Fig. 9 is a schematic diagram of the structure and process of another granulating apparatus according to the present invention.

[0114] Fig. 10 shows a schematic diagram of a heat exchanger according to the present invention.

[0115] Fig. 11 shows a schematic cross-sectional diagram of a heat exchanger according to the present invention.

[0116] Fig. 12 shows a schematic diagram of a drum of a buffer tank according to the present invention.

[0117] Fig. 13 is a schematic cross-sectional diagram of a drum of a buffer tank according to the present invention.

[0118] Fig. 14 shows a schematic diagram of another heat exchanger according to the present invention.

[0119] Fig. 15 shows an enlarged cross-sectional view along the straight line A-A in Fig. 14.

[0120] Fig. 16 is a cross-sectional view of a drum cylinder of another heat exchanger according to the present invention.

[0121] Fig. 17 shows a side view of Fig. 16.

[0122] Fig. 18 is a cross-sectional view of a feed device of another heat exchanger according to the present invention.

[0123] Fig. 19 shows an enlarged cross-sectional view along the straight line B-B in Fig. 1.

[0124] Fig. 20 is a cross-sectional view of the outlet device of another heat exchanger according to the present invention.

[0125] Fig. 21 shows an enlarged cross-sectional view along the straight line C-C in Fig. 1.

[0126] Fig. 22 is a three-dimensional view of a material guide spiral plate of another heat exchanger according to the present invention.

[0127] Fig. 23 is a schematic diagram of a slag particle waste heat recovery system according to another example of the present invention;

[0128] Fig. 24 is a schematic diagram of a heat exchanger according to another example of the present invention.

[0129] Fig. 25 is a schematic diagram of a heat exchanger cylinder according to another example of the present invention.

[0130] Fig. 26 is a schematic diagram of a superheater according to another example of the present invention.

[0131] Implementation of the invention

[0132] Referring to the detailed description of an embodiment of the invention, one or more examples are shown in the accompanying drawings. The detailed description uses numeric and letter reference numerals to designate elements in the drawings. Similar or identical reference numerals in the drawings and in the description have been used to designate similar or identical parts of the invention.

[0133] The limitations of each feature may be combined and used interchangeably here and throughout the description and claims unless the context dictates otherwise. For example, all ranges described in this document include components and devices provided that their functions are similar, indicating their interchangeability.

[0134] Example 1

[0135] With reference to Fig. 1, a waste heat recovery system for high temperature solid slag particles comprises:

[0136] a granulating device 11, which is a gas-cooled granulating device, comprising

[0137] a granulation chamber 111 having a box-shaped structure, in which an inlet 1111 for a slag flow is located at the upper part, and a slag chute 1100 is located above the inlet 1111 for a slag flow; at the lower part of the granulation chamber 111, an outlet 1112 for high-temperature slag is located;

[0138] a high-pressure nozzle 112, which is a supersonic nozzle, located in the upper part of one of the side walls of the granulating chamber 111. The outlet of the high-pressure nozzle 112 corresponds to the high-temperature molten slag 1200 entering from the slag flow inlet 1111; preferably, the high-pressure nozzle 112 is connected to an air compressor 113, an air processor 114 and a fan 115; the upper part of the other side wall of the granulating chamber 111 is equipped with an air outlet 1113, a dust collector 119 and a fan 120; more preferably, the high-pressure nozzle 112 is a Laval nozzle; the dust collector 119 is a cyclone dust collector or a bag dust collector;

[0139] a recuperative heat exchanger 12 comprising a cylinder 121 which is made in the form of a metal shell-and-tube structure and is provided with an inlet 1211 for a cooling medium and an outlet 1212 for a cooling medium at the ends.An inlet 1211 for a cooling medium and an outlet 1212 for a cooling medium are respectively connected to equipment for recovering waste heat; it is preferable that a device 1215 for distributing a cooling medium is installed on the side of an outlet 1212 for a cooling medium; an inlet opening 1213 is located on the side wall of the cylinder near an outlet opening 1212 for a cooling medium and is connected to an outlet 1112 for high-temperature slag of the granulation device 11 by means of a transport pipeline; an outlet 1214 for low-temperature slag is located on the side wall of the cylinder 121 on the side of an inlet 1211 for a cooling medium of the recuperative heat exchanger 12; a spiral plate 122 having several through holes connected to each other is installed in the recuperative heat exchanger 12. Heat exchange tubes 123 are inserted into the through holes; It is preferable that a scraper be welded around the circumference to the outer surface of the outlet side of the cylinder;

[0140] a conveyor 125 located under the outlet 1214 for low-temperature slag of the recuperative heat exchanger 12, it is preferable that the conveyor 125 be a screw conveyor.

[0141] Waste heat recovery equipment contains:

[0142] steam drum 13, connected to inlet 1211 for cooling medium of recuperative heat exchanger 12 through downpipe and circulation pump 14; outlet 1212 for cooling medium of recuperative heat exchanger 12 is connected by pipeline to inlet for steam-water mixture of steam drum 13, and saturated steam pipe of steam drum 13 is connected to steam pipe network; water supply pipe of steam drum 13 is connected to water tank 118 through water pump 116, water purification device 117 and water pump 116'.

[0143] Preferably, the shell of the cylinder 121 of the recuperative heat exchanger 12 has a water-cooled wall structure comprising a cylinder heat exchange tube liner 1216, a central heat exchange tube 124, a spiral plate 122 located inside the cylinder 121, and a set 123 of heat exchange tubes passing through the spiral plates 122.

[0144] The method for recovering waste heat of slag particles in Example 1 includes the following:

[0145] 1) The molten slag enters the granulation device to granulate the molten slag to obtain slag particles, the air during the molten slag granulation process carries out contact heat exchange with the molten slag, and is discharged through the dust collector and fan;

[0146] 2) the slag particles enter the recuperative heat exchanger, where they carry out indirect contact heat exchange with water or steam from the steam drum through a set of heat exchange tubes, and the water or steam absorbs heat and then returns to the steam drum and / or superheater and evaporator for heat exchange; the low-temperature slag particles subjected to heat exchange are pushed onto the conveyor by the spiral plate 22 and discharged through the conveyor.

[0147] Example 2

[0148] With reference to Fig. 2, an embodiment of a waste heat recovery system for high-temperature solid slag particles is shown, comprising:

[0149] a granulating device 21, which is a gas-cooled granulating device, comprising:

[0150] a granulation chamber 211 having a box-shaped structure, in which a slag flow inlet 2111 is located at the upper part, and a slag chute 2100 is located above the slag flow inlet 2111; an outlet 2112 for high-temperature slag is located at the lower part of the granulation chamber 211;

[0151] a high-pressure nozzle 212 which is a supersonic nozzle located at the upper portion of one of the side walls of the granulation chamber 211; an outlet of the high-pressure nozzle 212 corresponds to the high-temperature slag 2200 coming from the slag flow inlet; an air outlet 2113, a dust collector 213 and a fan 214 are located at the upper portion of the other side wall of the granulation chamber 211; preferably, the high-pressure nozzle 212 is connected to an air compressor 215, an air processor 216 and a fan 214'; more preferably, the high-pressure nozzle 212 is a Laval nozzle.

[0152] a recuperative heat exchanger 22 comprising a cylinder 221 with an inlet 2211 for slag particles and a valve at the upper portion corresponding to an outlet 2112 for high-temperature slag of the granulating device 1; an upper portion of one side wall of the cylinder 221 is provided with an air outlet 2212, and a lower portion of the other side wall is provided with an air supply pipeline 2213 and a fan 2214; a bottom of the cylinder 221 is provided with an outlet 2215 for slag particles and a valve; heat exchange tubes 222 are disposed inside the cylinder 221, and both ends (namely, an inlet and an outlet) of the heat exchange tubes 222 are disposed outside the cylinder 221 and are connected to the waste heat recovery equipment 25 through pipelines; preferably, a guide plate 223 that directs a uniform flow of falling slag particles is located at the upper portion inside the cylinder 221 below the slag inlet 2211;more preferably, the lower portion inside the cylinder 221 is provided with an air distribution device 224, and the preferred air distribution device 224 is an air distribution plate;

[0153] a conveyor 23 located below the slag particle outlet 2215 of the cylinder 221; preferably, the conveyor 23 is a screw conveyor or a belt conveyor;

[0154] dust collector 24, the inlet end of which is connected to the air outlet 2212 of the cylinder 221 of the recuperative heat exchanger 22 via a pipeline and valve F1; the outlet of the dust collector 24 is connected via a pipeline to the equipment 25 for recovering waste heat.

[0155] Preferably, the waste heat recovery equipment 25 comprises:

[0156] a superheater 251 and an evaporator 252 located in a sealed container 253, and an air inlet 2531 is located on the sealed container 253 and connected to the outlet of the dust collector 24 through a pipeline; an outlet 2532 of the sealed container 253 is connected to the air cleaner 255 through a pipeline and a fan 254; it is preferable that the evaporator 252 and the superheater 251 have a spiral-tube structure;

[0157] a steam drum 256, the inlet of which is connected via a pipeline to the water outlet of the heat exchange tube 222; the outlet for saturated steam of the steam drum 256 is connected to the inlet of the superheater 251 via a pipeline and valve 257, and the outlet pipeline of the superheater 251 is connected to the network of steam pipes; the water inlet of the steam drum 256 is connected to the outlet of the evaporator 252 via a pipeline and water pump 257', and the inlet of the evaporator 252 is connected to the water tank 258 via a pipeline and water pump 257''; preferably, the water purification device 259 is located in the inlet pipeline of the evaporator 252.

[0158] The method for recovering waste heat of slag particles in Example 2 comprises the following:

[0159] 1) The molten slag enters the granulation device to granulate the molten slag to obtain slag particles, the air during the molten slag granulation process carries out contact heat exchange with the molten slag, and is discharged through the dust collector and fan;

[0160] 2) The slag particles enter the recuperative heat exchanger, where the slag particles carry out indirect contact heat exchange with water or steam from the steam drum through a set of heat exchange tubes, and the water or steam absorbs heat and then returns to the steam drum and / or superheater and evaporator for heat exchange; the slag particles fall uniformly under the action of the guide plate of the recuperative heat exchanger, and in the process of falling, they exchange heat with the air blown out by the air distribution equipment located at the bottom of the recuperative heat exchanger, slowing down the falling time.

[0161] 3) The water supply to the recuperative heat exchanger is provided by the steam drum, and the supplied water absorbs heat and then returns to the steam drum; the heat released by the hot air from the recuperative heat exchanger is transferred to the superheater, and the water is finally converted into superheated steam in the superheater for discharge to the outside.

[0162] Example 3

[0163] With reference to Fig. 3, another embodiment of a waste heat recovery system for high temperature solid slag particles is shown, comprising:

[0164] a heat exchanger 31 with a metal shell-and-tube structure, divided from top to bottom into a superheat section 3101 and an evaporation section 3102; a first heat exchange tube 32 and a second heat exchange tube 33 are respectively located in the superheat section 3101 and the evaporation section 3102;

[0165] a steam drum 34, an inlet 341, an outlet 342 for saturated steam, an outlet 343 for saturated water and an inlet 344 for a saturated steam-water mixture are located on the steam drum; the outlet 342 for saturated steam is connected to the inlet end of the first heat exchange tube 32 in the superheating section 3101 of the heat exchanger 31 via a pipeline, and the outlet end of the first heat exchange tube 32 is connected to the steam pipe network through the buffer tank 35 via a pipeline; the outlet 343 for saturated water is connected to the inlet end of the second heat exchange tube 33 in the evaporation section 3102 of the heat exchanger 31 via a pipeline and a circulation pump 36; the outlet end of the second heat exchange tube 33 is connected via a pipeline to the inlet 344 for the saturated steam-water mixture of the steam drum 34;

[0166] guide plates 37, vertically located at certain intervals inside the heat exchanger 31, with through holes for the passage of the first and second heat exchange tubes 32, 33;

[0167] device 38 for loading and distributing material, located in the upper part of the heat exchanger 31;

[0168] a material distribution trough 39 located inside the heat exchanger 31 and under the material loading and distribution device 38; high-temperature slag particles 3100 enter the heat exchanger 31 through the material loading and distribution device 38 through the material distribution trough 39; and

[0169] outlet 310 located at the outlet at the bottom of heat exchanger 31.

[0170] Also with reference to Fig. 4, the waste heat recovery system for high temperature solid slag particles also comprises:

[0171] a disturbing rod 3111 inserted between the first heat exchange tube 32 and the second heat exchange tube 33 in the heat exchanger 31, wherein one end of the disturbing rod is fixed to the fixed base 3112, and the other end of the disturbing rod protrudes beyond the heat exchanger 31; a plurality of disturbing levers 3113 are arranged at intervals along the axial direction on the body of the disturbing rod 3111, and the axis of the disturbing lever 3113 and the axis of the disturbing rod 3111 form an angle; it is preferable that adjacent disturbing levers 3113 are installed antisymmetrically;

[0172] drive device 3114, the output end of which is connected to the end of the excitation rod 311 protruding beyond the heat exchanger 31.

[0173] It is preferable that the drive device 3114 is designed as a worm and a worm wheel, wherein the worm wheel is coaxially connected to the end of the exciting rod 3111.

[0174] The method for recovering waste heat of slag particles in Example 3 comprises the following:

[0175] 1) The high-temperature slag particles are uniformly distributed in the inner upper part of the heat exchanger by the material loading and distributing device and the material distributing trough, forming a horizontal material surface, and pass downward under the action of gravity;

[0176] 2) The saturated water flows out of the steam drum under the action of the circulation pump and enters the second heat exchange tube of the evaporation section of the heat exchanger; after heat exchange with high-temperature slag particles, it turns into a saturated steam-water mixture, which then returns to the steam drum through the pipeline, ensuring the separation of steam and water;

[0177] 3) The saturated steam from the steam drum enters the first heat exchange tube of the superheat section of the heat exchanger under the action of pressure difference; after heat exchange with high-temperature slag particles, superheated steam is generated, which then enters the buffer tank through the pipeline and finally enters the steam pipe network;

[0178] 4) high-temperature slag particles are converted into low-temperature slag particles through heat exchange with the first and second heat exchange tubes, moved to the outlet at the bottom of the heat exchanger, and discharged from the heat exchanger through the outlet device.

[0179] It is preferable that if the slag flow rate is low, the steam pipeline in the superheat section is shut off and switched to saturated steam production, ensuring that the outlet of the evaporator section pipeline is a steam-water mixture.

[0180] Example 3 is mainly divided into three cycles:

[0181] 1. The heat exchange tube is located in the evaporator and superheat sections of the heat exchanger. Saturated water flows out of the steam drum and enters the evaporator section under the action of a circulation pump. After heat exchange with high-temperature slag particles, the saturated water turns into a mixture of saturated water and steam, which then enters the steam drum, ensuring separation of steam and water.

[0182] 2. The saturated steam from the steam drum enters the superheat section of the heat exchanger under the action of pressure difference, exchanges heat with high-temperature slag particles, forms superheated steam, enters the buffer tank, and finally enters the steam pipe network.

[0183] 3. High-temperature slag particles are transported to the material loading and distribution device and uniformly distributed at the top of the heat exchanger through a material distribution trough, forming a horizontal material surface. Under the force of gravity, the high-temperature slag particles flow downwards within the heat exchanger, and heat exchange tubes and guide plates restrict the flow of slag particles, preventing slag particle flow deviation at the macroscopic level. When the slag particles reach the bottom of the heat exchanger, they are discharged from the heat exchanger through a discharge device. The low-temperature slag particles then proceed to the next processing stage.

[0184] During operation, ensure that there is a steam-water mixture at the outlet of the heat exchanger evaporation section pipeline; the device distributes the material so that the surface of the material is flat and there is no difference in height between the guide plates; the discharge device must be able to adjust the flow rate of the slag.

[0185] Example 4

[0186] With reference to Figs. 5 and 7, Example 4, based on Example 1, further comprises:

[0187] at least one high-temperature tank 55 located between the granulating device 111 and the recuperative heat exchanger 52; an inlet 551 connected to the high-temperature slag outlet 112 of the granulating device 111 and an inlet valve are located at an upper portion of the high-temperature tank 55; an outlet 552 connected to the inlet 5213 of the cylinder 521 of the recuperative heat exchanger 52 and an outlet valve are located at a lower portion of the high-temperature tank 55; an air inlet 553, an air supply pipeline and a fan 554 are located at a lower portion of one side wall of the high-temperature tank 55; an air outlet 555 is located at an upper portion of the opposite side wall and is connected to the dust collector 57 through a pipeline and a valve; it is preferable that a temperature detecting device 56 is installed in the pipeline;It is preferable that the air distribution equipment 556 connected to the air pipeline is located at the lower part inside the high-temperature tank 55; In the example, the air distribution equipment 556 is an air distribution plate; it is more preferable that the filter mesh 5501, the insulation material 5502 and the outer shell 5503 are located on the side wall of the high-temperature tank 55 from the inside to the outside;

[0188] Waste heat recovery equipment contains:

[0189] steam drum 53, connected to the inlet 5211 for the cooling medium of the recuperative heat exchanger 52 through a downpipe and a circulation pump 54; the outlet 5212 for the cooling medium of the recuperative heat exchanger 52 is connected by a pipeline to the inlet for the steam-water mixture of the steam drum 53, and

[0190] a superheater 58 and an evaporator 59 disposed in a sealed container 510, wherein an inlet 51001 and an outlet 51002 are disposed on the sealed container 510; the inlet is connected to an outlet pipe of the dust collector 57 through a pipe; the outlet pipe of the sealed container 510 is connected through a pipe to a fan 520' and an air cleaner 531; the saturated steam pipe of the steam drum 53 is connected to the inlet of the superheater 58 through a saturated steam valve 533, and the outlet of the superheater 58 is connected to a steam pipe network; the inlet pipe of the evaporator 59 is connected to a water purification device 517, a water pump 516 and a water tank 518; water pump 532 is located on the outlet pipeline of evaporator 59 and is connected to the water supply pipeline of steam drum 53.

[0191] Slag particles first enter a high-temperature storage tank for temporary storage and then enter a recuperative heat exchanger. During temporary storage of slag particles in the high-temperature tank, the hot air generated in the high-temperature tank is directed to the waste heat recovery equipment for heat exchange after dust removal by a dust collector. It is preferable to use multiple high-temperature tanks arranged in parallel.

[0192] Example 5

[0193] With reference to Figs. 6 and 7, Example 5, based on Example 2, further comprises:

[0194] at least one high-temperature tank 66 located between the granulating device 211 and the recuperative heat exchanger 22.

[0195] An inlet 551 connected to an outlet 112 at the bottom of the granulating tank 211 and an inlet valve are disposed at the top of the high-temperature tank 66; an outlet 552 connected to an inlet 2211 for slag particles of the cylinder 221 of the recuperative heat exchanger 22 and an outlet valve are disposed at the bottom of the high-temperature tank 66; an air inlet 553, an air supply pipeline and a fan 554 are disposed at the bottom of one side wall of the high-temperature tank 66; an air outlet 555 disposed at the top of the opposite other side wall and connected to the inlet pipeline of the dust collector 24 through a pipeline; it is preferable that a temperature detecting device 67 is installed in the pipeline; the air distribution equipment 556 is located at the bottom of the high-temperature tank 66 and is connected to the air supply pipeline;the air distribution equipment 556 is preferably an air distribution plate and is connected to a fan; more preferably, a filter mesh 5501, an insulating material 5502 and an outer shell 5503 are arranged on the side wall of the high-temperature tank 66 from the inside to the outside;

[0196] Slag particles first enter a high-temperature storage tank for temporary storage, and then enter a recuperative heat exchanger. During temporary storage of slag particles in the high-temperature tank, the hot air generated in the high-temperature tank is directed to the waste heat recovery equipment for heat exchange after dust is removed by a dust collector. It is preferable to use multiple high-temperature tanks arranged in parallel.

[0197] Example 6

[0198] With reference to Fig. 8, another embodiment is shown of a gas-water granulation device, which can replace the gas-cooled granulation device in the previous examples. Preferably, the gas-water granulation device comprises:

[0199] a granulation tank 611 having a box-shaped structure, wherein an inlet 6111 for a slag flow is located at the upper part of the granulation tank, and a slag chute 6100 is located above the inlet 6111 for a slag flow; an outlet 6112 for a slag flow is located at the lower part of the granulation tank 611;

[0200] high pressure nozzle 612, which is a spray nozzle or a gas-liquid dual-flow nozzle, located on the upper side wall of the granulation tank 611; the outlet of the high pressure nozzle 612 corresponds to the high-temperature molten slag 6200 supplied through the slag flow inlet 6111; the high pressure nozzle 612 is connected to the gas-water mixer 629, and the gas-water mixer 629 is respectively connected to the compressed air supply pipeline and the air flow control valve 6291 and the water supply pipeline with the water flow control valve 6292; the outlet port 6114 for the gas-water mixture, the filter 626, the gas-water separator 627 and the fan 628 are located at the upper part of the other side wall of the granulation tank 611.

[0201] Example 7

[0202] With reference to Fig. 9, another embodiment is shown of a rotary bowl granulation device that can replace the gas-cooled granulation device in the previous examples. The rotary bowl granulation device comprises:

[0203] a granulation chamber 711 having a box-shaped structure, wherein the slag flow inlet 7111 is located at the upper portion of the granulation chamber, and the slag flow outlet 7112 is located at the lower portion of the granulation chamber; air inlets 7115, 7115', air supply pipes and fans 734, 734' are located at the lower portion of the side wall of the granulation chamber 711, and an air outlet 7113, an air discharge pipe, a dust collector 719 and a fan 720 are located at the upper portion of the other side wall of the granulation chamber 711;

[0204] rotating motor 735 located in the center of granulating chamber 711;

[0205] rotary bowl 736 located at the output end of the rotating motor 735.

[0206] Example 8

[0207] With reference to Fig. 10 and 11, the structure of the recuperative heat exchanger 22 in Example 2 is also shown, comprising:

[0208] a drum cylinder 81, wherein an inlet 8101 for a cooling medium and an outlet 8102 for a cooling medium are located at both ends of the drum cylinder and respectively connected to external pipelines through rotary joints; an inlet for high-temperature slag particles and an inlet pipeline 8103 are located on a side wall of the drum cylinder 81 near the outlet 8102 for a cooling medium, and an outlet for low-temperature slag particles and an outlet pipeline 8104 are located on a side wall of the drum cylinder 81 near the inlet 8101 for a cooling medium; the drum cylinder 81 is installed with a downward inclination toward the outlet side for a cooling medium, which ensures the movement of high-temperature slag particles from the inlet end to the outlet end inside the drum cylinder 81;

[0209] a plurality of lifting plates 82, wherein the lifting plates 82 are L-shaped, with one end thereof arranged vertically at intervals along the inner wall of the drum cylinder 81 around the circumference;

[0210] the heat exchange tubes 83 are respectively located in the center of the drum cylinder 81, on the inner wall of the drum cylinder 81 and on the inner side of the lifting plates 82;

[0211] a drive device (not shown in the drawing) comprising a toothed ring, a drive motor and corresponding support structures located outside the drum cylinder 81.

[0212] Preferably, the drum cylinder 81 is composed of an inner cylinder 811, an outer cylinder 812, and an insulating material 813 between the inner cylinder 811 and the outer cylinder 812.

[0213] Preferably, the heat exchange tubes 83 comprise a set 831 of type A heat exchange tubes and a set 832 of type B heat exchange tubes; on the outer wall 831 of the set of type A heat exchange tubes, vertical fins 8311 are formed around the circumference, forming finned tubes; the set 831 of type A heat exchange tubes is located in the center of the drum cylinder 81, and preferably the fins 8311 are annular fins, columnar fins or plate fins; the set 832 of type B heat exchange tubes is located on the lifting plates 82 or on the inner wall of the drum cylinder 81.

[0214] It is preferable that the heat exchange tubes 83 be arranged in a drum cylinder with multiple tube passes, and the number of tube passes is odd; it is preferable that the resistance of the passes of each heat exchange tube be the same.

[0215] Example 9

[0216] Referring to Fig. 12 and 13, based on Example 8, the drum 91 of the buffer tank may also be connected in series before the inlet for high-temperature slag particles of the recuperative heat exchanger 22, comprising:

[0217] a drum 91 of a buffer tank, wherein the inlet and the inlet pipe 9101 are located on one side wall of the drum of the buffer tank, and the outlet and the outlet pipe 9102 are located on the other side wall of the drum of the buffer tank; the drum 91 of the buffer tank is installed with an inclination toward the outlet side, which ensures the movement of high-temperature slag particles from the inlet end to the outlet end inside the cylinder;

[0218] first lifting plates 92, which are L-shaped, with one end thereof located vertically at intervals along the inner wall of the drum 91 of the buffer tank around the circumference;

[0219] a first drive device (not shown in the drawings) comprising a toothed ring, a first drive motor and corresponding support structures located on the outer wall of the drum of the buffer tank.

[0220] Example 10

[0221] With reference to Fig. 14-22, another structure of the recuperative heat exchanger 22 in Example 2 is further illustrated, comprising:

[0222] a drum cylinder 101 that is horizontally disposed and mainly consists of a cylinder 1011, a material guide spiral plate 1012 and a set of heat exchange tubes 1013; the material guide spiral plate 1012 is welded to the inner wall of the cylinder 1011, and a plurality of through holes 10121 are formed on the material guide spiral plate 1012; the set of heat exchange tubes 1013 are inserted through the through holes of the material guide spiral plate 1012 and are uniformly arranged inside the cylinder 1011; the cylinder 1011 is covered with an insulating layer on the outside;

[0223] a feeding device 102 and a discharging device 103, respectively located at the ends of the drum cylinder 101;

[0224] a support roller device 104 located at the lower part of the drum cylinder near the end with the discharge device of the drum cylinder 101;

[0225] a holding roller device 105 located at the lower part of the drum cylinder near the end of the drum cylinder 101 on which the feeding device is located;

[0226] transmission device 106 located on the support roller device 104; the drum cylinder 101 is supported by the support roller device 104 and the holding roller device 105, and it can perform a continuous rotational motion under the action of the transmission device 106.

[0227] A set of heat exchange tubes are evenly distributed inside the cylinder.

[0228] Preferably, the cylinder 1011 of the drum cylinder 101 is composed of three sections, which are respectively made of heat-resistant stainless steel, stainless steel and alloy steel, sequentially forming a high-temperature section, a medium-temperature section and a low-temperature section.

[0229] Preferably, the transmission device 106 is composed of a main transmission system and an auxiliary transmission system that are mutually self-locking, and the main motor of the main transmission system uses a variable speed motor.

[0230] Referring to Fig. 18 and 19, the feeding device 102 according to the present invention comprises:

[0231] a first fixed base 1021, wherein the first connecting tubular body 10211 is disposed at an upper portion of the first fixed base; one end of the cylinder 1011 of the drum cylinder 101 is inserted into one end of the first connecting tubular body 10211 of the first fixed base 1021 by a fit with a gap therebetween and sealed by a sealing device 1024; an inlet hole 102111 and an outlet connecting tube 10212 are formed at the upper portion of the tubular body 10211; preferably, the distance L between the drum cylinder 1011 passing into the first connecting tubular body 10211 of the first fixed base 1021 and the center line of the outlet connecting tube 10212 is half the radius of the inlet hole of the outlet connecting tube 10212;

[0232] the first blocking plate 1022 inserted into the other end of the first connecting tubular body 10211 of the first fixed base 1021 by a fit with a gap therebetween and sealed by a sealing device 1024'; a plurality of fastening holes 10221 are formed on the first blocking plate 1022 for passing the set of heat exchange tubes 1013, and one end of the set of heat exchange tubes 1013 is welded to the first blocking plate 1022; preferably, the hatch 10222 is located in the center of the first blocking plate 1022;

[0233] a first rotating connecting pipe 1023, rigidly connected to the first locking plate 1022 by means of a flange.

[0234] Referring to Fig. 20 and 21, the outlet device 103 according to the present invention comprises:

[0235] a second fixed base 1031, wherein the second connecting tubular body 10311 is disposed at an upper portion of the second fixed base; the other end of the cylinder 1011 of the drum cylinder 101 is inserted into one end of the second connecting tubular body 10311 of the second fixed base 1031 by a fit with a gap therebetween and is sealed by a sealing device 1035; an exhaust gas outlet 103111 and an exhaust gas connecting pipe 10312 are formed at an upper portion of the second connecting tubular body 10311; the exhaust outlet 103112 and the corresponding exhaust pipe 10313 are disposed on one side of the middle or lower portion of the second connecting tubular body 10311; preferably, the outlet pipe 10313 is located tangentially around the circumference of the second connecting tubular body 10311;

[0236] a second blocking plate 1032 inserted into the other end of the second connecting tube body 10311 of the second fixed base 1031 by a fit with a gap therebetween and sealed by a sealing device 1035'; a plurality of fastening holes 10321 are formed on the second blocking plate 1032 for passing the heat exchange tube set 1013, and the other end of the heat exchange tube set 1013 is welded to the second blocking plate 1032; preferably, the hatch 10322 is located in the center of the second blocking plate 1032;

[0237] a second rotating connecting pipe 1033, rigidly connected to the second locking plate 1032 by means of a flange;

[0238] a plurality of scrapers 1034, wherein the scrapers are uniformly arranged around the circumference of the inner wall of the drum cylinder 1011 in the drum cylinder 1011 inside the second connecting pipe 10311; preferably, the angle between the scraper 1034 and the tangent direction of the circumference of the drum cylinder 101 is 40-50°; one end of the scraper 1034 is welded to the drum cylinder 101, and the other end is welded and connected to the second locking plate 1032.

[0239] Preferably, the length of the material guide spiral plate outside the cylinder is 100-200mm.

[0240] It is preferable that the distance between the end of the drum cylinder that exits into the second connecting pipe and the second blocking plate 32 is 500-800 mm.

[0241] During operation, the horizontally positioned drum cylinder is supported by a supporting roller device and a holding roller device, and it can perform continuous rotational motion under the action of the main driven transmission system of the transmission device. The rotation of the drum cylinder drives the material guide spiral plate 32, which in turn causes high-temperature solid particles to move from right to left in the gap between the inner wall of the drum cylinder and the outer surface of the heat exchange tubes. The heat exchange medium flows from left to right inside the heat exchange tubes, ensuring that there is no direct contact between the high-temperature solid particles and the heat exchange medium, thereby meeting the requirements of indirect heat transfer and heat exchange.

[0242] The main transmission system and the auxiliary transmission system of the transmission device are mutually self-locking. That is, when the main transmission system is activated, the auxiliary transmission system cannot be activated, and vice versa. The main transmission system is activated during operation, but the auxiliary transmission system cannot be activated. The auxiliary transmission system is activated only when the drum cylinder is undergoing maintenance or the main engine is turned off.

[0243] Example 11

[0244] With reference to Fig. 23-26, another waste heat recovery system for high temperature solid slag particles according to the present invention is also shown, comprising:

[0245] Heat exchanger 1110, containing:

[0246] a heat exchange cylinder 11101, wherein a feed box 11102, a discharge box 11103 and a corresponding inlet port 111021, an outlet port 111031 and an outlet port 111032 for exhaust gases are arranged at both ends of the heat exchange cylinder;

[0247] water collector 11104 and steam-water collector 11105 are respectively located at the ends of outlet box 11103 and feed box 11102 of heat exchange cylinder 11101;

[0248] the water collector rotary joint 11106 and the steam-water collector rotary joint 11107 are respectively located at the ends of the outlet box 11104 and the feed box 11105 of the heat exchange cylinder 11101;

[0249] double support and holding roller devices11108, located on both sides of the heat exchanger cylinder 11101;

[0250] rotary drive device 11109 located under the middle part of the heat exchange cylinder 11101;

[0251] steam drum 1120, pressure pipe 11201, downpipe 11202, steam outlet pipe 11203, vent pipe 11204, safety valve 11205, pressure gauge 11206, water level sensor 11207, steam drum blowdown pipe 11208, emergency water discharge pipe 11209 and water inlet pipe 11210; wherein

[0252] the steam drum 1120 is connected to the rotary joint 11107 of the steam outlet of the heat exchanger 1110 through the pressure pipe 11201, and is connected to the rotary joint 11106 of the water inlet of the heat exchanger 1110 through the downpipe 11202; the heat exchanger 1110 and the steam drum 1120 form a closed circulation system; the downpipe 11202 is connected in parallel with the booster pipe 11211, and the booster pump 1130 is disposed on the booster pipe 11211 to provide additional power for circulating the steam and water passing through the booster pump 1130;

[0253] The superheater 1140 is sequentially equipped from top to bottom with a preheating module 1141, a superheating module 1142, and a combustion module 1143; the steam drum 1120 is connected to the preheating module 1141 through a water inlet pipe 11210 and to the superheating module 1142 through a steam outlet pipe 11203;

[0254] the blowdown expansion tank 1150, the blowdown pipe 11212 of the heat exchanger are located at the end of the downcomer 11202 of the steam drum 1120 and the rotary joint 11106 of the water inlet of the heat exchanger 1110, the blowdown pipe 11212 of the heat exchanger is connected to the blowdown expansion tank 1150;

[0255] a water tank 116 equipped with a liquid level sensor 1164, an inlet pipe of the water tank is provided with an electric regulating valve 1163, and an outlet pipe of the water tank is connected to an inlet of a water supply pump 1170; an outlet pipe 1171 of the water supply pump 1170 is connected to a water inlet 11411 of a preheating module 1141 of a superheater 1140; a water outlet 11412 of the preheating module 1141 is connected to a steam drum 1120 through a water supply pipe 11210 of the steam drum 1120; a bypass pipe 1172 is disposed between the outlet pipe 1171 of the water supply pump 1170 and the inlet pipe 11210 of the steam drum 1120; when the superheater 1140 is under maintenance due to a malfunction, the preheating module 1141 of the superheater 1140 may be short-circuited via the bypass pipe 1172;the water tank liquid level sensor 1164 is connected to the electric control valve 1163 on the inlet pipeline, which controls the volume of water supplied to the water tank depending on the liquid level in the water tank, ensuring the required volume of water in the water tank and preventing incidents related to water shortage.

[0256] Continuous spiral tube supporting plates 111013 are welded to the inner wall of the heat exchange cylinder 11101, the continuous spiral tube supporting plates 111013 are spirally distributed along the axis inside the heat exchange cylinder 11101; corresponding through holes are formed on the spiral tube supporting plate of the cylinder, and a plurality of heat exchange tubes 111014 are inserted into the through holes of the spiral tube supporting plate 111013; both ends of the heat exchange cylinder 11101 are provided with flange tube plates 111015, and both ends of the heat exchange tube 111014 are respectively attached to two flange tube sheets 111015; two flange tube plates 111015 are fixedly connected to the steam-water collector 11105 and the water collector 11104, respectively; one end of the heat exchange tube 111014 is connected to the water collector 11104, and the other end of the heat exchange tube 111014 is connected to the steam-water collector 11105;the water collector 11104 is rotatably connected to the rotary joint 11106 for inlet of water, and the steam-water collector 11105 is rotatably connected to the rotary joint 11107 for outlet of steam, wherein graphite material is used for sealing the joint; the steam-water collector 11105 and the water collector 11104 rotate together with the heat exchange cylinder 11101.

[0257] Referring to Fig. 25, the heat exchange cylinder 11101 is provided with an inner cylinder wall 111011 and an outer cylinder wall 111012, the inner cylinder wall 111011 and a plurality of heat exchange tubes 111014 form a heat exchange space, and an insulating material is placed between the inner cylinder wall 111011 and the outer cylinder wall 111012; end plates 111016 are disposed at the ends of the inner cylinder wall 111011 and the outer cylinder wall 111012, and a plurality of outlet scrapers are welded between the end plates 111016 and the flange tube plate 111015 on the outlet side.

[0258] When the heat exchanger 1110 is in operation, the high-temperature slag enters the heat exchange cylinder 11101 through the feed box 11102 from the inlet port 111021. The rotary drive device 11109 drives the drum 11101 of the heat exchanger to rotate and ensures the translational movement of the high-temperature slag through the spiral support tube plate 111013 inside the heat exchange cylinder 11101. When the high-temperature slag reaches the outlet box 11103, it is lifted to the outlet port 111031 by the outlet scrapers 111017 and discharged from the heat exchanger 1110 through the outlet port 111031.

[0259] The top of steam drum 1120 is equipped with a safety valve 11205 and a pressure gauge 11206 to detect the pressure inside the steam drum and ensure the safe operation of the steam drum. If the pressure in the steam drum exceeds the upper limit of the working pressure, the valve on the vent pipe 11204 is opened, reducing the pressure in the steam drum to the working pressure, and then the valve on the vent pipe 11204 is closed.

[0260] The lower part of the steam drum 1120 is equipped with a steam drum blowdown pipe 11208 and an emergency water discharge pipe 11209. The emergency water discharge pipe 11209 is connected to the steam drum blowdown pipe 11208 and is connected to the blowdown expansion tank 1150. The side wall of the steam drum is equipped with a water level sensor 11207, which is used to detect the water level inside the steam drum. When the water level in the steam drum exceeds the upper limit of the safe water level, the valve on the emergency water discharge pipe is opened and the water level is quickly reduced to a safe level. When the water level in the steam drum drops below the lower limit of the safe water level, the system stops operating to ensure safe operation.

[0261] As shown in Fig. 26, the superheater 1140 is a preheating module 1141, a superheating module 1142, and a combustion module 1143 arranged in series from top to bottom.

[0262] The combustion module 1143 comprises a furnace 11431, a burner 11432, an exhaust gas circulation pipe 11433, and a circulation fan 11434; the fuel gas and air are discharged from the burner 11432, they are completely mixed and burned in the furnace 11431 to produce a high-temperature exhaust gas. The high-temperature exhaust gas is mixed with the low-temperature exhaust gas drawn out by the circulation fan 11434 to form a medium-high-temperature exhaust gas, which flows upward into the superheating module 1142. The circulation fan 11434 regulates the speed of the return flow of exhaust gas in the exhaust gas circulation line 11433, thereby regulating the temperature of the exhaust gas entering the superheating module 1142, ensuring that the outgoing superheated steam meets the process requirements.

[0263] The superheat module 1142 comprises a steam inlet 11421, a steam inlet manifold 11422, a steam outlet manifold 11423, a steam outlet 11424 and a set of superheater tubes 11425.

[0264] The steam outlet tube 11203 from the steam drum 1120 is connected to the steam inlet 11421 of the superheating module 1142. The saturated steam from the steam drum 1120 is supplied to the steam inlet header 11422 through the steam inlet 11421 of the superheating module 1142. The saturated steam is uniformly distributed over the superheater tube set 11425 through the steam inlet header 11422. The medium-high temperature exhaust gas generated by the combustion module 1143 passes upward through the superheating module 1142, heating the saturated water vapor in the superheater tube set 11425 to the state of superheated steam. Superheated steam is collected through steam outlet manifold 11423 and then sent to the pipeline through steam outlet 11424 on the superheater module's steam outlet manifold for user use. After heat exchange, the exhaust gas temperature decreases and continues to flow to preheater module 1141.

[0265] The preheating module 1141 comprises a water inlet 11411, a water inlet manifold 11412, a water outlet manifold 11413, a water outlet 11414, and a set of preheating tubes 11415.

[0266] The outlet pipe 1171 of the water supply pump is connected to the water inlet 11411 of the pre-heating module 1141. Cold water from the water tank 1160 is supplied to the water inlet manifold 11412 of the pre-heating module 1141 through the water inlet 11411 of the pre-heating module 1141. The cold water is evenly distributed over the set of pre-heating tubes 11415 through the water inlet manifold 11412. The exhaust gas after heat exchange in the superheating module 1142 passes upward through the preheating module 1141, heating the cold water in the set 11415 of preheating tubes to 90℃, which is then collected by the outlet manifold 11413 for water of the preheating module 1141, and the outlet 11414 for water on the outlet manifold 11413 for water is connected to the inlet pipe 11210 for water of the steam drum 1120, and hot water is supplied to the steam drum 1120.

[0267] The working process of Example 11 is as follows:

[0268] The water supply pump 1170 supplies cold water from the water tank 1160 to the preheating module 1141 of the superheater 1140 through the pipeline. The cold water is preheated by the preheating module 1141 of the superheater 1140, and it is converted into hot water, which is then sent to the steam drum 1120 through the steam drum water supply pipe 11210. The hot water is sent to the rotary joint 11106 for inlet of the heat exchanger through the downpipe 11202, and the water manifold 11104 evenly distributes the hot water through the heat exchange tube 111014. The high-temperature slag continuously enters the heat exchanger 1110 through the inlet port 111021, and the heat exchanger 1110 continuously rotates. The spiral plate 111013 for supporting the tubes transports high temperature slag to the outlet end.During this process, the high-temperature slag continuously contacts with the heat exchange tubes 111014, and the hot water in the heat exchange tubes 111014 absorbs the heat transferred by the high-temperature material, turning into high-temperature water and saturated steam; due to the decrease in density, a difference in the density of hot water occurs in the downcomer 11202, and the high-temperature water and saturated steam then enter the steam drum 1120 through the pressure pipe 11201. The high-temperature water and saturated steam are separated in the steam drum 1120. The saturated steam is supplied to the superheating module 1142 of the superheater 1140 through the outlet pipe 11203 of the steam drum, where it is heated to the state of superheated steam and sent for external use. High-temperature water enters steam drum 1120 and is returned to heat exchanger 1110 through downcomer 11202, continuing the heat absorption cycle. The slag, after heat exchange, is discharged from heat exchanger 1110 through outlet 111031.The slag dust and exhaust gas generated in the heat exchanger 1110 are directed to the dust removal system through the exhaust gas outlet 111032.

[0269] The above descriptions are merely preferred specific embodiments of the present invention, and the protection scope of the present invention is not limited thereto. Within the technical scope disclosed in the present invention, equivalent replacements or modifications made by any skilled person familiar with the technical field based on the technical solutions and inventive concepts disclosed in the present invention fall within the protection scope of the present invention.

Claims

1. A waste heat recovery system for high temperature slag solid particles comprising: a granulating device, preferably a gas-cooled granulating device, a gas-water granulating device, or a rotary bowl granulating device; a rotating recuperative heat exchanger comprising an inlet for slag particles corresponding to a slag outlet of a granulation device, an outlet for slag particles and a set of heat exchange tubes located inside the recuperative heat exchanger, wherein the set of heat exchange tubes has an inlet for a cooling medium and an outlet for a cooling medium, and the cooling medium is preferably water; and waste heat recovery equipment, wherein the inlet for the cooling medium and the outlet for the cooling medium are respectively connected to the waste heat recovery equipment via pipelines; in which the waste heat recovery equipment contains: a steam drum comprising a steam drum water inlet, a steam drum steam outlet, a saturated steam outlet, and a steam-water mixture inlet; water tank; wherein the water inlet of the steam drum is connected to the water tank, the cooling medium inlet is connected to the water outlet of the steam drum, and the cooling medium outlet is connected to the steam-water mixture inlet.

2. A waste heat recovery system for high temperature slag solid particles according to claim 1, further comprising a conveyor and a dust collector located below the outlet for slag particles, wherein the inlet end of the dust collector is connected to the air outlet of the recuperative heat exchanger via a pipeline, and the outlet of the dust collector is connected via a pipeline to waste heat recovery equipment.

3. A waste heat recovery system for high-temperature slag solid particles according to claim 1 or 2, wherein the heat exchanger comprises a cylinder formed as a metal shell-and-tube structure, and an inlet for slag particles and an outlet for slag particles are respectively located on a side wall of the cylinder on the outlet side for the cooling medium and on a side wall of the cylinder on the inlet side for the cooling medium, wherein spiral plates with interconnected through holes into which heat exchange tubes are inserted are located inside the cylinder; preferably, the outer shell of the cylinder has a water-cooled wall structure containing a cylinder heat exchange tube liner, a central heat exchange tube, a spiral plate located inside the cylinder, and a set of heat exchange tubes passing through the spiral plate.

4. A waste heat recovery system for high-temperature slag solid particles according to claim 1, wherein the heat exchanger comprises: a drum cylinder, wherein the inlet for slag particles is located on the side wall of the drum cylinder near the outlet for the cooling medium, and the outlet for slag particles is located on the side wall of the drum cylinder near the inlet for the cooling medium; the drum cylinder is installed with a downward slope, towards the outlet for the cooling medium, which allows the slag particles to move from the inlet for slag particles to the outlet for slag particles; preferably, the drum cylinder consists of an inner cylinder, an outer cylinder and an insulating material between the inner cylinder and the outer cylinder; lifting plates arranged at intervals on the inner wall of the drum cylinder along the circumference of the inner wall of the drum cylinder, wherein the lifting plates are L-shaped; a cylinder drive device comprising a toothed ring, a drive motor and a support structure located outside the drum cylinder, wherein the cylinder drive device is used to rotate the drum cylinder, wherein The heat exchange tubes are located in the center of the drum cylinder, on the inner wall of the drum cylinder and on the inner side of the lifting plates.

5. The waste heat recovery system for high-temperature slag solid particles according to claim 4, wherein the set of heat exchange tubes comprises a set of type A heat exchange tubes and a set of type B heat exchange tubes, a plurality of fins are vertically arranged circumferentially on the outer wall of the set of type A heat exchange tubes to form a finned tube, the set of type A heat exchange tubes is located in the center of the drum cylinder, and the fins are preferably ring fins, columnar fins or plate fins; the set of type B heat exchange tubes is located on lifting plates or on the inner wall of the drum cylinder.

6. A waste heat recovery system for high temperature slag solid particles according to claim 5, wherein the set of heat exchange tubes is arranged in a drum cylinder with multiple tube passes and the number of tube passes is odd; it is preferable that the flow resistance of each heat exchange tube is the same.

7. A waste heat recovery system for high temperature slag solid particles according to any one of paragraphs 4-6, further comprising: a buffer tank drum having an inlet and an inlet pipe on one side of its side wall and an outlet and an outlet pipe on the other side; the buffer tank drum is installed with an inclination toward the outlet side, which ensures the movement of slag particles from the inlet end to the outlet end inside the cylinder; first material lifting plates arranged vertically at intervals along the inner wall of the drum of the buffer tank along the circumference, and the first material lifting plates have an L-shape; and a first drive device comprising a toothed ring, a first drive motor and corresponding support structures located on the outer wall of the drum of the buffer tank.

8. A waste heat recovery system for high temperature slag solid particles according to any one of paragraphs 1-3, wherein the heat exchanger comprises: a drum cylinder located horizontally, wherein at the ends of the drum cylinder there is a feed device containing an inlet for slag particles, and an outlet device containing an outlet for slag particles; a material-guiding spiral plate located inside the drum cylinder, wherein the material-guiding spiral plate has through holes for the passage of a set of heat exchange tubes; a support roller device located at the bottom of the cylinder near the end with the cylinder outlet device; a holding roller device located at the bottom of the cylinder near the end of the cylinder on which the feed device is located; a transmission device located on a support roller device; wherein the cylinder is supported by means of the support roller device and the holding roller device and it can perform a continuous rotational movement under the action of the transmission device; wherein a set of heat exchange tubes is evenly distributed inside the cylinder.

9. A waste heat recovery system for high temperature slag solids according to claim 8, wherein the heat exchanger satisfies one or more of the following conditions: the cylinder consists of three sections, respectively made of heat-resistant stainless steel, stainless steel and alloy steel, sequentially forming a high-temperature section with a temperature of 750-550°C, a medium-temperature section with a temperature of 550-350°C and a low-temperature section with a temperature of less than 350°C; the transmission device consists of a main transmission system and an auxiliary transmission system, which are mutually self-locking, and the main motor of the main transmission system uses a variable speed motor; The length of the spiral plate guiding the material, protruding beyond the cylinder, is 100-200 mm.

10. A waste heat recovery system for high temperature slag solid particles according to claim 1 or 2, wherein the heat exchanger comprises: a heat exchanger cylinder provided with a feed box containing an inlet for slag particles and a discharge box containing an outlet for slag particles at the ends of the heat exchanger cylinder, wherein the ends of the heat exchanger cylinder near the discharge box and the feed box are respectively provided with a water collector and a steam-water collector; double support and holding roller devices located on both sides of the heat exchanger cylinder; a rotary drive device located at the bottom of the middle part of the heat exchanger cylinder; and the steam drum and heat exchanger form a closed circulation system; The waste heat recovery equipment comprises a superheater, which is sequentially equipped from top to bottom with a preheating module, a superheating module and a combustion module; the steam drum is connected to the preheating module through a water inlet pipe and to the superheating module through a steam outlet pipe; the blowdown pipe and the emergency water drain pipe are located at the bottom of the steam drum, and the blowdown pipe and the emergency water drain pipe are connected to the blowdown expansion tank; a control valve, preferably an electric control valve, is located on the inlet pipe of the water tank, and the outlet pipe of the water tank is connected to the inlet of the water supply pump, the outlet pipe of the water supply pump is connected to the inlet of the superheater; it is preferable that the water tank is equipped with a liquid level sensor.

11. A waste heat recovery system for high temperature slag solid particles according to claim 10, wherein the waste heat recovery system for high temperature slag solid particles satisfies one or more of the following requirements: continuous spiral tube support plates are welded to the inner wall of the heat exchanger cylinder, the continuous spiral tube support plates are distributed spirally along the axis inside the heat exchanger cylinder; corresponding through holes are formed on the spiral tube support plates, and a set of heat exchange tubes is inserted into the through holes of the spiral tube support plates; both ends of the heat exchanger cylinder are provided with flange tube plates, and the ends of the heat exchange tube are respectively fixed on two flange tube plates, which are fixedly connected to a steam-water collector and a water collector, respectively, one end of the heat exchange tube is connected to the water collector, and the other end of the heat exchange tube is connected to the steam-water collector;the water collector is rotatably connected to a rotary joint for inlet of water, the steam-water collector is rotatably connected to a rotary joint for outlet of steam, and the rotary joint is sealed with graphite material; the steam-water collector and the water collector rotate together with the heat exchanger cylinder; The heat exchanger cylinder is provided with an inner cylinder wall and an outer cylinder wall, the inner cylinder wall and the heat exchange tube form a heat exchange space, and an insulating material is placed between the inner cylinder wall and the outer cylinder wall; end plates are located on the inner cylinder wall and the outer cylinder wall and ends, and outlet scrapers are welded circumferentially between the end plates and the flange tube plates on the outlet side.

12. A waste heat recovery system for high-temperature slag solid particles according to claim 11, in which The superheater is equipped sequentially from top to bottom with a preheating module, a superheating module and a combustion module; the combustion module contains a furnace, a burner, a flue gas circulation pipeline and a circulation fan; The superheating module contains a steam inlet, a steam inlet manifold, a steam outlet manifold, a steam outlet, and a set of superheating tubes; a steam outlet pipe from the steam drum is connected to the steam inlet of the superheating module, and saturated steam from the steam drum is supplied to the steam inlet header through the steam inlet of the superheating module, and the saturated steam is uniformly distributed over the set of superheating tubes through the steam inlet header; The superheating module comprises a water inlet, a water inlet manifold, a water outlet manifold, a water outlet and a set of preheating tubes; the outlet pipe of the water supply pump is connected to the water inlet, and water from the water tank is supplied to the water inlet manifold through the water inlet, and the water is uniformly distributed over the set of preheating tubes through the water inlet manifold; the exhaust gas after heat exchange in the superheating module passes upward through the preheating module, heating the water in the set of preheating tubes after being collected by the water outlet manifold on the preheating module, the water outlet on the water outlet manifold is connected to the water inlet pipe of the steam drum and the heated water is supplied to the steam drum.

13. A waste heat recovery system for high-temperature slag solid particles according to claim 1 or 2, wherein the heat exchanger comprises a cylinder, wherein the slag particle inlet and the slag particle outlet are respectively located at the upper end and the bottom of the cylinder, the upper portion of one side wall of the cylinder is provided with an air outlet, and the lower portion of the other side wall is provided with an air inlet duct and a fan; it is preferable that a guide plate that directs a uniform flow of slag particles is located in the upper portion inside the cylinder; it is preferable that the lower portion inside the cylinder is equipped with air distribution equipment.

14. A waste heat recovery system for high temperature slag solid particles according to claim 1 or 2, wherein the heat exchanger is a metal shell and tube structure, the interior of which is divided into a superheat section at the top and an evaporator section at the bottom, wherein a first set of heat exchange tubes and a second set of heat exchange tubes are located in the superheat section and the evaporator section, respectively, wherein the inlet end of the first set of heat exchange tubes is connected to the saturated steam outlet of the steam drum, and the outlet end of the first set of heat exchange tubes is connected to the steam tube network by a pipeline through a buffer tank, the inlet end of the second set of heat exchange tubes is connected to the saturated water outlet of the steam drum, and the outlet end of the second set of heat exchange tubes is connected to the saturated steam-water mixture inlet of the steam drum, and the heat exchanger is provided with guide plates arranged vertically at intervals,and the trough for distributing the material is located under the slag inlet and on the guide plates there are through holes for the passage of heat exchange tubes.

15. A waste heat recovery system for high-temperature slag solid particles according to paragraph 5, further comprising: a disturbing rod inserted between the first heat exchange tube and the second heat exchange tube in the heat exchanger, wherein one end of the disturbing rod is attached to a fixed base, and the other end of the disturbing rod protrudes beyond the heat exchanger; disturbing levers are arranged at intervals in the axial direction on the body of the disturbing rod, and the axis of the disturbing lever and the axis of the disturbing rod form an angle; it is preferable that adjacent disturbing levers are installed antisymmetrically; a drive device whose output end is connected to the end of a disturbing rod protruding beyond the heat exchanger.

16. A waste heat recovery system for high-temperature slag solid particles according to claim 6, wherein the drive device is made in the form of a worm and a worm wheel, wherein the worm wheel is coaxially connected to the end of the excitation rod.

17. A waste heat recovery system for high temperature slag solids according to any one of claims 1 to 3 or 13, further comprising: at least one tank located between the granulation device and the recuperative heat exchanger, wherein an inlet connected to the slag outlet of the granulation device is located on the top of the tank, and an outlet connected to the slag particle inlet of the heat exchanger is located at the bottom of the tank; the bottom of one side wall of the tank is provided with an air inlet, an air duct and a fan, while the top of the opposite side wall is provided with an air outlet that is connected to the inlet end of a dust collector via a duct, and the outlet of the dust collector is connected to the waste heat recovery equipment via a duct;It is preferable that a temperature detection device be installed in the pipeline connected to the dust collector; it is preferable that the air distribution equipment connected to the air pipeline be located at the bottom of the tank; it is more preferable that a filter mesh, an insulating material and an outer shell be located on the side wall of the tank from the inside to the outside.

18. A waste heat recovery system for high temperature slag solids according to any one of claims 1 to 9 or 13, wherein the waste heat recovery equipment further comprises a superheater and / or an evaporator, wherein the inlet of the superheater is connected to the saturated steam outlet of the steam drum, and the outlet of the superheater is connected to the steam pipe network; the inlet of the evaporator is connected to the water tank, and the outlet of the evaporator is connected to the water inlet of the steam drum.

19. A waste heat recovery system for high-temperature slag solid particles according to claim 18, wherein the superheater and evaporator are located in a sealed container, and the air inlet is located on the sealed container and is connected to the outlet of the dust collector through a pipeline; the outlet of the sealed container is connected to the air cleaner through a pipeline and a fan; it is preferable that the evaporator and superheater have a spiral design; it is preferable that a water purification device is additionally installed between the evaporator and the water tank.

20. A waste heat recovery system for high temperature slag solid particles according to any one of paragraphs 1-19, wherein the gas-cooled granulation device comprises: a granulation chamber having a box-shaped structure, in which an inlet for a flow of molten slag is located at the top of the granulation chamber, and a trough for a flow of molten slag is located above the inlet for the flow of molten slag; an outlet for a flow of slag particles is located at the bottom of the granulation chamber; a high-pressure nozzle located on a side wall of the granulation chamber, wherein the outlet of the high-pressure nozzle faces the inlet for the flow of molten slag, and the air outlet, dust collector and fan are located at the top of the other side wall of the granulation chamber; preferably, the high-pressure nozzle is a Laval nozzle.

21. A waste heat recovery system for high temperature slag solid particles according to any one of paragraphs 1-19, wherein the gas-water granulation device comprises: a granulation chamber having a box-shaped structure, in which an inlet for a flow of molten slag is located at the top of the granulation chamber, and a trough for a flow of molten slag is located above the inlet for the flow of molten slag; an outlet for a flow of slag particles is located at the bottom of the granulation chamber; a high-pressure nozzle located on the side wall of the granulation chamber, wherein the outlet of the high-pressure nozzle faces the inlet for the molten slag flow, and the outlet for the gas-water mixture, the gas-water separator and the fan are located in the upper part of the other side wall of the granulation chamber, wherein the high-pressure nozzle is a spray nozzle or a gas-liquid dual-flow nozzle.

22. A waste heat recovery system for high temperature slag solid particles according to any one of paragraphs 1-19, wherein the rotary bowl granulation device comprises: a granulation chamber having a box-shaped structure, in which an inlet for a flow of molten slag is located at an upper portion of the granulation chamber, and an outlet for the molten slag is located at a lower portion, an air inlet, an air supply duct and a fan are located at a lower portion of one side wall of the granulation chamber, and an air outlet, an air discharge duct, a dust collector and a fan are located at an upper portion of the other side wall of the granulation chamber; a rotating motor located in the center of the granulation chamber; and a rotary bowl located at the output end of the rotating motor.

23. A method for recovering waste heat from solid particles of high-temperature slag, comprising the following steps: a) introducing molten slag into a granulating device for granulating molten slag to obtain slag particles, and air during the granulating process of molten slag carries out contact heat exchange with the molten slag and is discharged through a dust collector and a fan; preferably, gas-cooled granulation, gas-water granulation or rotary bowl granulation are used for granulating molten slag; b) introducing slag particles into a rotating recuperative heat exchanger, where the slag particles perform indirect contact heat exchange with water or steam from a steam drum through a set of heat exchange tubes, and the water or steam absorbs heat to produce heat exchange water, saturated steam or superheated steam, wherein the slag particles perform indirect contact heat exchange with water or steam from the steam drum through a set of heat exchange tubes, and / or a sleeve of a cylinder heat exchange tube, and / or a central heat exchange tube; the slag particles subjected to heat exchange are pushed onto a conveyor by a spiral plate and discharged through the conveyor; c) send the slag particles after heat exchange outside via a conveyor.

24. The method for recovering waste heat for solid particles of high-temperature slag according to claim 23, wherein in step b) the slag particles fall uniformly under the action of guide plates of the recuperative heat exchanger and, during the falling process, they contact and exchange heat with air blown out by air distribution equipment located in the lower part of the recuperative heat exchanger.

25. The method for recovering waste heat for high-temperature slag solid particles according to claim 23, wherein in step b) saturated water from the steam drum enters the second heat exchange tube in the evaporator section of the recuperative heat exchanger, after heat exchange with the high-temperature slag particles it turns into a saturated mixture of water and steam, which is then returned to the steam drum through a steam and water separation pipeline; the saturated steam from the steam drum enters the first heat exchange tube of the superheating section of the recuperative heat exchanger under the action of a pressure difference and after heat exchange with the slag particles it forms superheated steam, and then passes through a pipeline to the steam tube network through a buffer tank; preferably, if the slag flow rate is below a set value, the pipeline for steam of the superheating section is closed.

26. The method for recovering waste heat for solid particles of high-temperature slag according to claim 23, wherein before step b), the slag particles are first fed into a storage tank for temporary storage and then fed into a recuperative heat exchanger; during the temporary storage of the slag particles in the tank, the heated air generated in the tank is directed to waste heat recovery equipment for heat exchange after dust removal using a dust collector; it is preferable to use tanks arranged in parallel.

Images