High-temperature steel slag air-cooling crushing waste heat recovery steam power generation device and method

Abstract

The invention provides a high-temperature steel slag air cooling crushing waste heat recovery steam power generation device and method.The device comprises a slag tank, a slag overturning device, a slag crushing device, an air cooling device, a transfer device, a slag cooling device, a waste heat recovery device, a steam generation device, a heat storage device and a power generation device body; the slag breaking device is arranged in the air cooling device, the transferring device is connected with the air cooling device and the slag cooling device in a transferring mode, the waste heat recovery device is connected with the air cooling device and the heat storage device, and the steam generation device is connected with the slag cooling device and the heat storage device. Cooling water of the slag cooling device absorbs heat to generate high-temperature pressurized water, and steam output from the waste heat recovery device and / or the steam generation device enters the heat storage device; through heat energy recycling of the hot-state materials and stabilization treatment of the steel slag, short-process efficient heat energy recycling and conversion power generation treatment of the steel slag can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of molten steel slag processing, and in particular to a device and method for high-temperature steel slag air-cooling, crushing, and waste heat recovery steam power generation. Background Art

[0002] In the steel production process, about 0.1-0.12 tons of slag are produced per ton of steel, and the annual slag production exceeds 100 million tons. Among them, molten slag contains considerable latent heat and sensible heat. At present, the pretreatment processes of slag include hot stuffing, hot pouring, drum method, wind quenching and other processes. Among them, hot stuffing, hot pouring and drum method all use wet methods to treat slag, and the steam generated has a large dust content and unstable flow rate, and cannot be directly used for steam turbine power generation. Although the wind quenching method uses dry method to treat slag, the entire treatment process is carried out in a relatively open environment, which is seriously polluted and difficult to recover heat. These processes cannot achieve stable and reliable heat recovery of slag. Summary of the invention

[0003] In order to solve the above problems, the present invention provides a high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device and method, which can realize the short-process high-efficiency heat energy recovery, conversion and power generation of steel slag through the recovery and utilization of hot material heat energy and stabilization treatment of steel slag.

[0004] The present invention provides a high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device, comprising a slag pot, a slag turning device, a slag breaking device, an air-cooling device, a transfer device, a slag cooling device, a waste heat recovery device, a steam generating device, a heat storage device, and a power generation device. The slag turning device is arranged on a side outside the air-cooling device so as to be accessible, the slag breaking device is arranged in the air-cooling device, the transfer device is transported and connected between the air-cooling device and the slag cooling device, the waste heat recovery device is connected between the air-cooling device and the heat storage device, the steam generating device is connected between the slag cooling device and the heat storage device, the heat storage device is connected to the power generation device, the cooling water of the slag cooling device absorbs heat to generate high-temperature pressurized water, and the steam output from the waste heat recovery device and / or the steam generating device enters the heat storage device.

[0005] Furthermore, the slag cooling device includes an annular water-cooling tube group, and the cooling water in the annular water-cooling tube group absorbs heat to generate high-temperature pressurized water, and the high-temperature pressurized water enters the steam generating device to generate steam.

[0006] Furthermore, the slag pot can enter and exit the air cooling device and the slag breaking device through the slag turning device.

[0007] Furthermore, it also includes a dust removal system, which is connected to the waste heat recovery device and the air cooling device.

[0008] Furthermore, it also includes a control system, which controls the connection of the slag turning device, the slag breaking device, the air cooling device, the transfer device, the slag cooling device, the waste heat recovery device 7, the steam generating device, the heat storage device, the power generation device, and the dust removal system.

[0009] Furthermore, the slag breaking device comprises a fixed crushing bed and a slag breaking machine, the slag breaking machine is arranged on the fixed crushing bed, the fixed crushing bed is paved with a steel plate, the lower part of the steel plate is filled with castable material, and the upper part of the steel plate is paved with a steel slag cushion layer.

[0010] Furthermore, the air cooling device includes a fixed air cooling bed, a blower, a grooved grate plate, and a fire door. The fire door can be opened and closed and is arranged on one side of the air cooling device. The grooved grate plate is laid on the fixed air cooling bed, and the blower is connected to the lower part of the fixed air cooling bed.

[0011] Furthermore, a superheater is provided in the heat storage device, and an exhaust valve is provided between the heat storage device and the power generation device.

[0012] The present invention also provides a method for recovering steam power generation by using waste heat from air-cooled crushing of high-temperature steel slag, which uses the above-mentioned device for recovering steam power generation by using waste heat from air-cooled crushing of high-temperature steel slag, and comprises the following steps:

[0013] Step S1. The molten slag is loaded and crushed by rollers. The molten slag is placed in a slag pot and hoisted to a slag turning device via an overhead crane. The slag turning device enters a fixed crushing bed to dump the slag and transport the empty slag pot out. The fire door is closed and the slag crusher solidifies and crushes the molten slag to a state where it is no longer sticky.

[0014] Step S2. Cooling the high-temperature solid slag with air blast. The slag crusher pushes the crushed high-temperature solid slag to a fixed air cooling bed. The slag is left to stand. The blower blows in normal temperature air to cool the slag and discharge the high-temperature flue gas.

[0015] Step S3. Waste heat is recovered to generate steam, steam is stored for power generation, high-temperature flue gas is heat exchanged to generate steam, solid slag enters the slag cooling device for heat exchange to generate high-temperature pressurized water, high-temperature pressurized water enters the steam generating device to generate steam, and the steam output from the waste heat recovery device and / or the steam generating device is stored for power generation;

[0016] Step S4: discharging the solid slag. After the solid slag is cooled to a certain temperature, the discharge port of the cooling slag device is opened to discharge the solid slag.

[0017] Furthermore, the step S3 also includes that the high-temperature flue gas is heat exchanged to generate steam, the high-temperature flue gas discharged from the fixed air-cooled bed enters the waste heat recovery device to release heat, the cooling water absorbs heat to generate steam, the solid slag enters the slag cooling device for heat exchange to generate steam, and the solid slag is transported to the slag cooling device via the transfer device. When the steam pressure in the device reaches a certain threshold, the exhaust valve opens, and the superheated pressure steam drives the power generation device to generate electricity.

[0018] The present invention adopts a roller crushing-stabilization treatment-heat energy recovery method to treat molten steel slag. A slag crusher initially cools and crushes 1400-1600°C molten steel slag, pushes it to a fixed air cooling bed, and blast cools it to about 600°C-800°C. The slag is transported to a slag cooling device for further cooling, and the slag is discharged to 60°C-100°C. The high-temperature pressure steam generated in the process is subjected to superheating treatment by a heat storage device, and superheated steam with constant pressure is output to generate electricity. The roller crushing system cooperates with the heat exchange system to operate together, which can realize the continuous production of molten steel slag treatment and heat energy recovery power generation, and greatly improve the steel slag treatment efficiency and heat energy recovery utilization rate.

[0019] The device of the present invention occupies a small space, and the overall system can realize a fully enclosed processing environment, reduce the emission of dusty steam, and quickly reduce the slag temperature during the processing process, and the recovered heat energy generates steam for power generation. It has the technical effects of high degree of automation, good production continuity, high processing efficiency, small space occupation, heat energy recovery and utilization, and environmental emission compliance, and can meet the environmental emission and resource utilization requirements of steel slag treatment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0021] Figure 1 The overall operation schematic diagram of a high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device provided by the present invention;

[0022] Figure 2 A flow chart of a method for recovering waste heat from high-temperature steel slag through air-cooling and crushing to generate steam for power generation provided by the present invention.

[0023] Description of reference numerals:

[0024] 1- slag pot, 2- slag turning device, 3- slag breaking device, 4- air cooling device, 5- transfer device, 6- slag cooling device, 7- waste heat recovery device, 8- steam generating device, 9- heat storage device, 10- power generation device, 11- dust removal system, 12- control system, 31- fixed crushing bed, 32- slag breaking machine, 41- fixed air cooling bed, 42- blower, 43- grooved grate plate, 44- fire door, 91- superheater, 92- exhaust valve. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0027] See attached Figure 1 The present invention provides a high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device, comprising a slag pot 1, a slag turning device 2, a slag breaking device 3, an air cooling device 4, a transfer device 5, a slag cooling device 6, a waste heat recovery device 7, a steam generating device 8, a heat storage device 9, and a power generation device 10. The slag turning device 2 is arranged on the outer side of the air cooling device 4 so as to be accessible, the slag breaking device 3 is arranged in the air cooling device 4, the transfer device 5 transfers and connects the air cooling device 4 with the slag cooling device 6, the waste heat recovery device 7 connects the air cooling device 4 with the heat storage device 9, the steam generating device 8 connects the slag cooling device 6 with the heat storage device 9, the heat storage device 9 is connected to the power generation device 10, the cooling water of the slag cooling device 6 absorbs heat to generate high-temperature pressurized water, and the steam output from the waste heat recovery device 7 and / or the steam generating device 8 enters the heat storage device 9.

[0028] Furthermore, the slag cooling device 6 includes an annular water-cooling tube group 61, and the cooling water in the annular water-cooling tube group 61 absorbs heat to generate high-temperature pressurized water, and the high-temperature pressurized water enters the steam generating device 8 to generate steam.

[0029] Furthermore, the slag pot 1 can enter and exit the air cooling device 4 and the slag breaking device 3 through the slag turning device 2 .

[0030] Furthermore, it also includes a dust removal system 11, and the dust removal system 11 is connected to the waste heat recovery device 7 and the air cooling device 4.

[0031] Furthermore, it also includes a control system 12, which controls the slag turning device 2, the slag breaking device 3, the air cooling device 4, the transfer device 5, the slag cooling device 6, the waste heat recovery device 7, the steam generating device 8, the heat storage device 9, the power generation device 10, and the dust removal system 11 respectively.

[0032] Furthermore, the slag breaking device 3 comprises a fixed crushing bed 31 and a slag breaking machine 32. The slag breaking machine 32 is arranged on the fixed crushing bed 31. The fixed crushing bed 31 is paved with steel plates, the lower part of the steel plates is filled with castables, and a steel slag cushion layer is paved on the upper part of the steel plates.

[0033] Furthermore, the air cooling device 4 includes a fixed air cooling bed 41, a blower 42, a grooved grate plate 43, and a fire door 44. The fire door 44 can be opened and closed and is arranged on one side of the air cooling device 4. The grooved grate plate 43 is laid on the fixed air cooling bed 41, and the blower 42 is connected to the lower part of the fixed air cooling bed 41.

[0034] Furthermore, a superheater 91 is provided in the heat storage device 9 , and an exhaust valve 92 is provided between the heat storage device 9 and the power generation device 10 .

[0035] Furthermore, the roller of the slag breaker 32 needs to be cooled by water, and the cooling water used is industrial new water.

[0036] Furthermore, the fixed crushing bed 31 is paved with steel plates, the lower part of the steel plates is filled with castables, and a steel slag cushion is paved on the upper part of the steel plates. The steel slag cushion and the castables both play a role in heat insulation protection, reducing the structural damage of the bed body caused by high temperature.

[0037] Furthermore, the fixed air cooling bed 41 is provided with a grooved grate plate 43, which is a labyrinth ventilation design to ensure that there is no leakage during the slag processing; wherein, the slag on the fixed air cooling bed 41 stays for 15min-20min, and the normal temperature air blown in by the blower 42 exchanges the waste heat of the slag during the process. The temperature of the cooled slag is about 600℃-800℃, and the temperature of the discharged high-temperature flue gas is about 450℃.

[0038] Furthermore, a superheater 91 is provided in the heat storage device 9, which can achieve a steam superheat of 50°C-100°C; wherein, the slag discharge temperature is about 60°C-100°C.

[0039] Furthermore, the waste heat recovery device 7 is a medium-pressure waste heat boiler with a rated steam pressure of 1.6 MPa and a rated steam temperature of 300°C; wherein the dust removal system 11 is connected to the waste heat recovery device 7 to collect dust to achieve ultra-low emissions, and the cooling water used by the waste heat recovery device 7 is desalted water.

[0040] See attached Figure 2The present invention also provides a method for recovering steam power generation by using waste heat from high-temperature steel slag through air cooling and crushing, which uses the above-mentioned device for recovering steam power generation by using waste heat from high-temperature steel slag through air cooling and crushing, and comprises the following steps:

[0041] Step S1. The molten slag is loaded and crushed by rollers. The molten slag is placed in a slag pot 1 and hoisted to a slag turning device 2 via an overhead crane. The slag turning device 2 enters a fixed crushing bed 31 to dump the slag and transport the empty slag pot 1. The fire door 44 is closed. The slag crusher 32 solidifies and crushes the molten slag to a state where it is no longer sticky.

[0042] Step S2. The high-temperature solid slag is cooled by air blasting. The slag crusher 32 pushes the crushed high-temperature solid slag to the fixed air cooling bed 41. The slag is left to stand. The blower 42 blows in normal temperature air to cool the slag and discharge the high-temperature flue gas.

[0043] Step S3. Waste heat is recovered to generate steam, steam is stored for power generation, high-temperature flue gas is heat exchanged to generate steam, solid slag enters the slag cooling device 6 for heat exchange to generate high-temperature pressurized water, high-temperature pressurized water enters the steam generating device 8 to generate steam, and the steam output from the waste heat recovery device 7 and / or the steam generating device 8 is stored for power generation;

[0044] Step S4. discharging the solid slag. After the solid slag is cooled to a certain temperature, the discharging port of the cooling slag device 6 is opened to discharge the solid slag.

[0045] Furthermore, step S3 also includes that the high-temperature flue gas is heat exchanged to generate steam, the high-temperature flue gas discharged from the fixed air-cooled bed 41 enters the waste heat recovery device 7 to release heat, the cooling water absorbs heat to generate steam, the solid slag enters the slag cooling device 6 for heat exchange to generate steam, and the solid slag is transported to the slag cooling device 6 via the transfer device 5. When the steam pressure in the device reaches a certain threshold, the exhaust valve 92 is opened, and the superheated pressure steam drives the power generation device 10 to generate electricity.

[0046] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0047] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device, comprising a slag pot (1), a slag turning device (2), a slag breaking device (3), an air cooling device (4), a transfer device (5), a slag cooling device (6), a waste heat recovery device (7), a steam generating device (8), a heat storage device (9), and a power generation device (10), characterized in that: The slag turning device (2) is arranged on the outer side of the air cooling device (4) so ​​as to be accessible, the slag breaking device (3) is arranged in the air cooling device (4), the transfer device (5) transfers and connects the air cooling device (4) and the slag cooling device (6), the waste heat recovery device (7) connects the air cooling device (4) and the heat storage device (9), the steam generating device (8) connects the slag cooling device (6) and the heat storage device (9), the heat storage device (9) is connected to the power generating device (10), the cooling water of the slag cooling device (6) absorbs heat to generate high-temperature pressurized water, and the steam output from the waste heat recovery device (7) and / or the steam generating device (8) enters the heat storage device (9).

2. The high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device according to claim 1 is characterized in that: The slag cooling device (6) comprises an annular water-cooling tube group (61), wherein cooling water in the annular water-cooling tube group (61) absorbs heat to generate high-temperature pressurized water, and the high-temperature pressurized water enters the steam generating device (8) to generate steam.

3. The high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device according to claim 1 is characterized in that: The slag pot (1) can enter and exit the air cooling device (4) and the slag breaking device (3) through the slag turning device (2).

4. The high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device according to claim 1 is characterized in that: It also includes a dust removal system (11), wherein the dust removal system (11) is connected to the waste heat recovery device (7) and the air cooling device (4).

5. The high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device according to claim 1 is characterized in that: The invention also comprises a control system (12), wherein the control system (12) controls and connects the slag turning device (2), the slag breaking device (3), the air cooling device (4), the transfer device (5), the slag cooling device (6), the waste heat recovery device (7), the steam generating device (8), the heat storage device (9), the power generating device (10), and the dust removal system (11).

6. The high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device according to claim 1 is characterized in that: The slag breaking device (3) comprises a fixed crushing bed (31) and a slag breaking machine (32), wherein the slag breaking machine (32) is arranged on the fixed crushing bed (31), the fixed crushing bed (31) is paved with a steel plate, the lower part of the steel plate is filled with castable material, and the upper part of the steel plate is paved with a steel slag cushion layer.

7. The high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device according to claim 1 is characterized in that: The air cooling device (4) comprises a fixed air cooling bed (41), a blower (42), a grooved grate plate (43), and a fire door (44); the fire door (44) is openably and closably arranged on one side of the air cooling device (4); the grooved grate plate (43) is laid on the fixed air cooling bed (41); and the lower part of the fixed air cooling bed (41) is connected to the blower (42).

8. The high-temperature steel slag air-cooled crushing waste heat recovery steam power generation device according to claim 1 is characterized in that: A superheater (91) is provided in the heat storage device (9), and an exhaust valve (92) is provided between the heat storage device (9) and the power generation device (10).

9. A method for generating electricity by recovering waste heat from high-temperature steel slag by air cooling and crushing, using the device for generating electricity by recovering waste heat from high-temperature steel slag by air cooling and crushing according to any one of claims 1 to 8, characterized in that: The following steps are involved: Step S1. The molten slag is loaded and crushed by rollers. The molten slag is placed in a slag pot (1) and transported to a slag turning device (2) via an overhead crane. The slag turning device (2) enters a fixed crushing bed (31) to pour the slag and transport it out of the empty slag pot (1). The fire door (44) is closed. The slag crusher (32) solidifies and crushes the molten slag to a state where it is no longer sticky. Step S2. The high-temperature solid slag is cooled by air blasting. The slag crusher (32) pushes the crushed high-temperature solid slag to the fixed air cooling bed (41). The slag is left to stand. The blower (42) blows in normal temperature air to cool the slag and discharge the high-temperature smoke. Step S3. Recover waste heat to generate steam, store steam to generate electricity, use high-temperature flue gas for heat exchange to generate steam, solid slag enters the slag cooling device (6) for heat exchange to generate high-temperature pressurized water, the high-temperature pressurized water enters the steam generating device (8) to generate steam, and the steam output from the waste heat recovery device (7) and / or the steam generating device (8) is used for energy storage to generate electricity; Step S4. discharging the solid slag. After the solid slag is cooled to a certain temperature, the discharging port of the cooling slag device (6) is opened to discharge the solid slag.

10. A method for generating electricity by recovering waste heat from high-temperature steel slag by air cooling and crushing according to claim 9, characterized in that: The step S3 also includes: high-temperature flue gas is heat exchanged to generate steam, the high-temperature flue gas discharged from the fixed air-cooled bed (41) enters the waste heat recovery device (7) to release heat, the cooling water absorbs heat to generate steam, the solid slag enters the slag cooling device (6) to exchange heat to generate steam, the solid slag is transported to the slag cooling device (6) via the transfer device (5), and when the steam pressure in the device reaches a certain threshold, the exhaust valve (92) is opened, and the superheated pressure steam drives the power generation device (10) to generate electricity.

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