Dust heat recovery system for waste heat boiler of rotary hearth furnace

Abstract

The utility model relates to a dust heat recovery system of a rotary hearth furnace waste heat boiler, and belongs to the technical field of metallurgical production rotary hearth furnace processes. Providing an embedded scraper transporter (3) for transporting dust, and arranging a water cooling box body for cooling the dust on the embedded scraper transporter (3) along the transporting direction of the embedded scraper transporter (3); the water inlet side of the water-cooling box body is connected with a make-up pump (2), the water outlet side of the water-cooling box body is connected to a deaerator (5), and cooling water absorbing dust heat is conveyed to the deaerator (5) for deaeration and then exchanges heat with flue gas of a boiler (7). According to the system, the deoxygenization steam consumption is reduced, the heat utilization rate of the waste heat boiler is improved, the dust temperature is also reduced, and dust recovery is facilitated.

Description

Technical Field

[0001] The utility model belongs to the technical field of rotary hearth furnace technology in metallurgical production, and relates to a dust heat recovery system for a waste heat boiler of a rotary hearth furnace. Background Art

[0002] The rotary hearth furnace is a new ironmaking process developed in the last 30 years. The characteristics of the waste heat boiler of the rotary hearth furnace are large dust content, recyclable dust, and high dust temperature, ranging from about 1000℃ to about 200℃ in the waste heat boiler. The dust of the waste heat boiler of the conventional rotary hearth furnace is transported to the ash discharge valve through the buried scraper conveyor, and then collected and recycled by bags or carts. The heat of the dust is wasted and it is easy to burn the bags or carts. Utility Model Content

[0003] In view of this, the purpose of the utility model is to provide a dust heat recovery system for a rotary hearth furnace waste heat boiler to recover dust waste heat and reduce dust heat.

[0004] In order to achieve the above object, the utility model provides the following technical solutions:

[0005] A dust heat recovery system for a rotary hearth furnace waste heat boiler comprises a buried scraper conveyor for conveying dust, on which a water cooling box for cooling the dust is arranged along its conveying direction; the water inlet side of the water cooling box is connected to a water supply pump, and the water outlet side is connected to a deaerator, and the cooling water that absorbs the heat of the dust is conveyed to the deaerator for deoxidation and then exchanges heat with the flue gas of the boiler.

[0006] Optionally, the water inlet side of the water replenishment pump is connected to a water replenishment tank.

[0007] Optionally, two water replenishment pumps are provided, one for use and one for backup, and are respectively connected to the water cooling box.

[0008] Optionally, the high-temperature side of the water-cooling box is connected to the water supply pump, and the low-temperature side is connected to the deaerator.

[0009] Optionally, a plurality of water-cooling boxes are arranged in parallel, and the water inlets of all the water-cooling boxes are connected as a main water inlet and connected to the water replenishment pump.

[0010] Optionally, the deaerator is arranged on the top of the boiler.

[0011] Optionally, the deaerator is arranged independently.

[0012] Optionally, a ash discharge valve is provided on the buried scraper conveyor.

[0013] Optionally, a steam drum is provided on the boiler.

[0014] The beneficial effects of the utility model are:

[0015] The water in the water supply tank of the utility model is transported to the water-cooled box of the buried scraper conveyor through the water supply pump, and then transported to the deaerator for deoxidation after absorbing the heat of the dust. The water in the deaerator then enters the boiler body to exchange heat with the flue gas according to the conventional process. This system reduces the consumption of deoxidizing steam, improves the heat utilization rate of the waste heat boiler, and also reduces the dust temperature, making it easier to recover dust and reducing the difficulty of the subsequent dust transportation process.

[0016] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and will be apparent to those skilled in the art based on the following examination and research, or can be taught from the practice of the present invention to some extent. The objectives and other advantages of the present invention can be achieved and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be described in detail below in conjunction with the accompanying drawings, in which:

[0018] Figure 1 It is a schematic diagram of the utility model.

[0019] Figure numerals: 1 water supply tank, 2 water supply pump, 3 buried scraper conveyor, 4 ash discharge valve, 5 deaerator, 6 steam drum, 7 boiler. DETAILED DESCRIPTION

[0020] The following describes the implementation of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and the features in the embodiments can be combined with each other without conflict.

[0021] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present utility model. In order to better illustrate the embodiments of the present utility model, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0022] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "back" and the like indicate directions or positional relationships, they are based on the directions or positional relationships shown in the drawings, which 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 direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as a limitation on the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0023] See also Figure 1 , is a dust heat recovery system for a rotary hearth furnace waste heat boiler 7, providing an buried scraper conveyor 3 for conveying dust, and a water cooling box for cooling dust is arranged on it along its conveying direction; the water inlet side of the water cooling box is connected to a water supply pump 2, and the water outlet side is connected to a deaerator 5, and the cooling water absorbing the heat of the dust is conveyed to the deaerator 5 for deoxidation and then heat exchange with the flue gas of the boiler 7. A steam drum 6 is arranged on the boiler.

[0024] The water inlet side of the make-up water pump 2 is connected to the make-up water tank 1, and in some other embodiments, it can also be connected to a make-up water pipe, etc. In some embodiments, two make-up water pumps 2 are provided, one for use and one for backup, and they are respectively connected to the water-cooled box. In order to better absorb the heat of the high-temperature section of the waste heat boiler, the high-temperature side of the water-cooled box is connected to the make-up water pump 2, and the low-temperature side is connected to the deaerator 5. In order to improve the fault tolerance of the system and improve the heat absorption efficiency of the dust, several water-cooled boxes are arranged in parallel, and the water inlets of all water-cooled boxes are connected to the total water inlet and connected to the make-up water pump 2. In different embodiments, the deaerator 5 is arranged on the top of the boiler 7, and can also be independently arranged inside the pump room. The buried scraper conveyor is provided with an ash unloading valve, after which rear-end equipment such as a conveying trolley and a bag dust collector can be arranged.

[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the utility model.

Claims

1. A dust heat recovery system for a rotary hearth furnace waste heat boiler, characterized in that: A scraper conveyor (3) for conveying dust is provided, and a water cooling box for cooling the dust is arranged on the conveying direction thereof; The water inlet side of the water cooling box is connected to a water supply pump (2), and the water outlet side is connected to a deaerator (5). The cooling water that absorbs the heat of the dust is transported to the deaerator (5) for deoxygenation and then exchanges heat with the flue gas of the boiler (7).

2. The rotary hearth furnace waste heat boiler dust heat recovery system according to claim 1, characterized in that: The water inlet side of the water replenishment pump (2) is connected to the water replenishment tank (1).

3. The rotary hearth furnace waste heat boiler dust heat recovery system according to claim 1, characterized in that: Two water replenishment pumps (2) are provided, one for use and one for backup, and are respectively connected to the water cooling box.

4. The rotary hearth furnace waste heat boiler dust heat recovery system according to claim 1, characterized in that: The high-temperature side of the water-cooling box is connected to the water replenishment pump (2), and the low-temperature side is connected to the deaerator (5).

5. The rotary hearth furnace waste heat boiler dust heat recovery system according to claim 1, characterized in that: A plurality of water cooling boxes are arranged in parallel, and the water inlets of all the water cooling boxes are connected as a total water inlet and connected to the water replenishment pump (2).

6. The rotary hearth furnace waste heat boiler dust heat recovery system according to claim 1, characterized in that: The deaerator (5) is arranged on the top of the boiler (7).

7. The rotary hearth furnace waste heat boiler dust heat recovery system according to claim 1, characterized in that: The deaerator (5) is arranged independently.

8. The rotary hearth furnace waste heat boiler dust heat recovery system according to claim 1, characterized in that: The buried scraper conveyor (3) is provided with an ash discharge valve (4).

9. The rotary hearth furnace waste heat boiler dust heat recovery system according to claim 1, characterized in that: The boiler is provided with a steam drum (6).

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