Recycling system for lump ore drying waste heat

Abstract

The utility model relates to the technical field of lump ore drying production, in particular to a lump ore drying waste heat recycling system which comprises a dryer, a hot blast stove and a lump ore bin, the hot blast stove is externally connected with a gas pipeline, one side of the dryer is respectively connected with the lump ore bin and the hot blast stove, the other side of the dryer is connected with a smoke collecting hood, and a smoke exhaust pipeline is arranged on the smoke collecting hood. The smoke exhaust pipeline penetrates through the lump ore bin and then is connected with an inlet of the heat exchanger, a low-temperature smoke outlet in the heat exchanger is connected with a chimney through a smoke exhaust fan, and an air pipeline of a high-temperature air outlet in the heat exchanger is connected with the hot blast stove through an induced draft fan. According to the utility model, the technical problems of reasonably utilizing the waste heat of the exhaust flue gas of the lump ore drying production equipment and reducing the gas consumption of the blast furnace are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of lump ore drying production, in particular to a lump ore drying waste heat recycling system. Background Art

[0002] Lump ore is one of the important raw materials used in blast furnace ironmaking. Due to the influence of rain and snow environmental factors, the lump ore absorbs moisture during the stacking process. A large amount of water-containing lump ore enters the blast furnace, which will cause the temperature in the furnace to decrease, the fuel ratio to increase, and the production cost per ton of iron to increase. Patent CN111351369A discloses a device for drying lump ore in a storage yard using sintering ring cooling waste gas, including a ring cooler, an induced draft fan, a distribution pipe, a lump ore drying device and a discharge pipe. The sintering ring cooling waste gas generated by the ring cooler enters the induced draft fan through the flue. The induced draft fan is connected to the distribution pipe. Several drying branch pipes are installed on the distribution pipe. Each drying branch pipe is equipped with a valve. The induced draft fan can inject the sintering ring cooling waste gas into the warehouse body through the distribution pipe and the drying branch pipe. The sintering ring cooling waste gas through the warehouse body is discharged from the discharge pipe. Because the blocks are piled together in this structure, the hot flue gas moves from bottom to top, and the material layer is unevenly dried from top to bottom, and the drying effect of the blocks cannot be guaranteed.

[0003] In response to the above situation, some steel companies have proposed using blast furnace gas as fuel and utilizing rotary kilns, dryers and other equipment to dry the lump ore. However, using rotary kilns and dryers to dry the ore will increase the consumption of blast furnace gas and generate a large amount of waste heat. After dust removal, the heat is directly discharged into the atmosphere in the form of hot air, which makes it impossible to reasonably utilize the waste heat and causes a waste of resources. Utility Model Content

[0004] The embodiment of the utility model provides a lump ore drying waste heat recycling system to achieve the technical effect that hot air can be recycled and resource waste is reduced.

[0005] One aspect of the implementation of the utility model provides a lump ore drying waste heat recycling system, comprising a dryer, a hot blast furnace and a lump ore silo, the hot blast furnace is externally connected to a gas pipeline, one side of the dryer is respectively connected to the lump ore silo and the hot blast furnace, and the other side is connected to a smoke collecting hood, the smoke collecting hood is provided with a smoke exhaust duct, the smoke exhaust duct passes through the lump ore silo and is connected to an inlet of a heat exchanger, the low-temperature smoke outlet on the heat exchanger is connected to the chimney through a smoke exhaust fan, and the air duct of the high-temperature air outlet on the heat exchanger is connected to the hot blast furnace through an induced draft fan.

[0006] Compared with the prior art, the beneficial effects of the present invention are:

[0007] The utility model dries the ore blocks in the dryer through a smoke exhaust pipe that runs through a lump ore silo and waste heat from the lump ore, then uses a heat exchanger to exchange heat between the high-temperature smoke and air, so that the heated hot air is introduced into a hot blast furnace and mixed with coal gas to be ignited and burned to produce drying smoke to dry the ore blocks in the dryer, thereby reasonably and effectively utilizing the heat energy of the smoke and reducing energy waste.

[0008] Furthermore, the preferred solution adopted by the present invention is:

[0009] A plurality of branch pipes are arranged at the position of the smoke exhaust pipe corresponding to the lump ore bin, and a plurality of through holes are opened on the side wall of the lump ore bin corresponding to the branch pipes, and the branch pipes cooperate with the through holes to penetrate the lump ore bin and connect with the heat exchanger. The smoke exhaust pipe is passed through the lump ore bin through a plurality of branch pipes to preheat and dry the lump ore, which helps to increase the contact area between the lump ore and the smoke exhaust pipe.

[0010] The air pipe is equipped with an air regulating valve, which controls the air flow rate to ensure that the air can fully exchange heat and heat up in the heat exchanger.

[0011] A bag dust collector is installed on the smoke exhaust duct. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The drawings described herein are used to provide a further understanding of the present invention, constitute a part of the present application, and do not constitute a limitation of the present invention. In the drawings:

[0013] Figure 1 It is a structural schematic diagram of the utility model;

[0014] Figure 2 It is a schematic diagram of the structure of the branch pipeline in the lump ore silo;

[0015] In the figure: dryer 1; hot air furnace 2; lump ore silo 3; smoke exhaust fan 4; induced draft fan 5; smoke collecting hood 6; gas pipeline 7; air pipeline 8; smoke exhaust pipeline 9; branch pipeline 10; air regulating valve 11; heat exchanger 12; chimney 13; bag filter 14. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in combination with the implementation mode and the accompanying drawings. Here, the schematic implementation mode of the utility model and its description are used to explain the utility model, but are not used as a limitation of the utility model.

[0017] A lump ore drying waste heat recycling system is mainly composed of a dryer 1, a hot blast furnace 2 and a lump ore bin 3, etc. The burner of the hot blast furnace 2 is externally connected to a gas pipeline 7, and the air outlet of the hot blast furnace 2 is connected to the air inlet of the dryer 1. The lump ore bin 3 is funnel-shaped, and the bottom discharge port of the lump ore bin 3 is connected to the feed port of the dryer 1 through a feeding pipe.

[0018] The exhaust port of the dryer 1 is equipped with a smoke collecting hood 6, and the smoke collecting hood 6 is equipped with a smoke exhaust pipe 9. The smoke exhaust pipe 9 passes through the lump ore bin 3 and is connected to the pipe side inlet of the heat exchanger 12. The pipe side outlet of the heat exchanger 12 is connected to the chimney 13 through the smoke exhaust fan 4.

[0019] In this embodiment, a bag filter 14 is installed on the smoke exhaust duct 9 to filter and remove dust from the smoke exhausted by the dryer 1 .

[0020] When the smoke exhaust pipe 9 passes through the lump ore bin 3, a plurality of branch pipes 10 can be respectively arranged at the positions corresponding to the positions passing through the lump ore bin 3, and through holes corresponding to the number of branch pipes 10 are respectively opened on the two opposite side walls of the lump ore bin 3, and each branch pipe 10 is respectively sealed and connected to the side walls corresponding to its two ends to prevent leakage of the lump ore bin. In this embodiment, two branch pipes 10 are arranged, and the two branch pipes 10 can increase the contact area with the lump ore in the lump ore bin 3, and the two branch pipes 10 are respectively collected in the main pipe of the smoke exhaust pipe 9 before and after the lump ore bin 3, so as to be connected with the front and rear equipment.

[0021] The tube side outlet of the heat exchanger 12 is connected to the chimney 13 through the smoke exhaust fan 4; the shell side inlet of the heat exchanger 12 takes in normal temperature air, and the shell side outlet of the heat exchanger 12 is connected to the air duct 8, which is connected to the air inlet of the hot air furnace 2 through the induced draft fan 5.

[0022] In this embodiment, an air regulating valve 11 is installed in the air duct 8 between the induced draft fan 5 and the heat exchanger 12 , and the air flow rate is controlled by the air regulating valve 11 to ensure that the air can fully exchange heat and heat up in the heat exchanger 12 .

[0023] When the system is working, firstly, the lump ore is controlled to enter the dryer 1, and the burner of the hot blast furnace 2 is ignited. The flue gas generated by the ignition of the coal gas enters the dryer 1 through the hot blast furnace 2 to dry the lump ore in the dryer 1. The high-temperature flue gas generated after drying is introduced into the pipe side of the heat exchanger 12 through the exhaust fan 4 at a certain pressure and flow rate. When the exhaust pipe 9 passes through the lump ore bin, the high-temperature flue gas preheats and dries the lump ore in the lump ore bin 3 through the branch pipe 10; at the same time, the induced draft fan 5 introduces normal temperature air into the shell side of the heat exchanger 12 at a certain pressure and flow rate. After the high-temperature flue gas and the normal temperature air are heat exchanged in the heat exchanger 12, the low-temperature flue gas after cooling is discharged through the chimney 13, and the high-temperature flue gas after heating is sent to the burner through the induced draft fan 5 to mix with the coal gas and ignite to generate drying flue gas for use in the dryer 1, and then the high-temperature flue gas generated after drying is recycled by repeating the above process.

[0024] The utility model dries the lump ore by exhaust pipe 9 penetrating lump ore bin 3 and waste heat, and then uses heat exchanger 12 to exchange heat between high temperature flue gas and air, so that the heated hot air is introduced into hot blast furnace 2 and mixed with coal gas to ignite and burn to produce drying flue gas to dry the ore in dryer 1, so as to reasonably and effectively use flue gas heat energy and reduce energy waste. Since high temperature flue gas contains residual coal gas, there are safety hazards in directly using high temperature flue gas to dry lump ore. Therefore, this circulation system uses waste heat from exhaust pipe and heat exchanger to exchange heat between flue gas and air, so that residual coal gas components in flue gas will not leak out, thus ensuring the safety of production area and eliminating safety hazards.

[0025] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A waste heat recycling system for lump ore drying, comprising a dryer, a hot blast furnace and a lump ore silo, wherein the hot blast furnace is externally connected to a gas pipeline, one side of the dryer is respectively connected to the lump ore silo and the hot blast furnace, and the other side is connected to a smoke collecting hood, wherein a smoke exhaust duct is provided on the smoke collecting hood, and the characteristics are: The smoke exhaust pipe passes through the lump ore silo and is connected to an inlet of the heat exchanger. The low-temperature smoke outlet on the heat exchanger is connected to the chimney through the smoke exhaust fan. The air pipe of the high-temperature air outlet on the heat exchanger is connected to the hot air furnace through the induced draft fan.

2. The lump ore drying waste heat recycling system according to claim 1 is characterized in that: The smoke exhaust pipe is provided with a plurality of branch pipes, and the side wall of the lump ore bin is provided with a plurality of through holes corresponding to the branch pipes, and the branch pipes cooperate with the through holes to penetrate the lump ore bin and then are connected with the heat exchanger.

3. The lump ore drying waste heat recycling system according to claim 1 is characterized in that: An air regulating valve is provided on the air pipeline.

4. The lump ore drying waste heat recycling system according to claim 1 is characterized in that: A bag dust collector is installed on the smoke exhaust duct.

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