Plasma heating blast furnace blast method

Abstract

The invention discloses a plasma heating blast furnace blast method which comprises the steps that a heating device formed by connecting a plurality of plasma cabinets in parallel generates cold air with certain pressure and flow under the action of an air blower, the cold air is conveyed through a cold air pipeline, part of the cold air enters the plasma cabinets through the cold air pipeline, and part of the cold air does not pass through the plasma cabinets; cold air passing through the plasma cabinet is heated to 2500 DEG C or above under the action of the plasma heating device and directly enters an unheated cold air pipeline to heat the cold air, and finally high-temperature blast air heated by the plasma cabinet is mixed with cold air of an air blower to form high-temperature blast air needed by the blast furnace to enter the blast furnace to participate in combustion reaction; the blast temperature can be quickly and efficiently increased through the plasma cabinet, and the purpose of reducing the carbon consumption of the blast furnace is achieved.

Description

Technical Field

[0001] The present invention relates to a method for heating blast furnace air by plasma. Background Art

[0002] Hot blast stoves for heating blast furnace air all use gas heating. First, the checker bricks of the hot blast stove are heated by gas, and then the blast is heated by the checker bricks. The thermal efficiency is low. Because of burning gas, carbon emissions are generated, and the investment is large and the operation is relatively complex. Under the background of the current goal of energy conservation and consumption reduction, it is urgent to reduce the consumption of fossil energy and use green electricity generated by renewable energy for ironmaking. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention provides a method for heating blast furnace air by plasma, so that the blast can quickly and efficiently increase the air temperature through the plasma cabinet, achieving the purpose of reducing the carbon consumption of the blast furnace.

[0004] Specifically, the present invention is realized through the following technical solutions: A method for heating blast furnace air by plasma, including a heating device composed of a plurality of plasma cabinets connected in parallel. Under the action of a blower, cold air with a certain pressure and flow rate is transported through a cold air pipeline. A part of the cold air pipeline enters the plasma cabinet, and a part of the cold air does not pass through the plasma cabinet. The cold air passing through the plasma cabinet is heated to above 2500 °C under the action of the plasma heating device and directly enters the unheated cold air pipeline to heat the cold air. Finally, the high-temperature blast heated by the plasma cabinet is mixed with the cold air of the blower to form the high-temperature blast required by the blast furnace and enters the blast furnace to participate in the combustion reaction; According to the air temperature requirement, 5-10 groups of 8MW plasma cabinets are added to heat the cold air; According to the production requirement, the air volume entering the plasma cabinet and the data of the plasma cabinets put into operation are determined. In order to facilitate the input and cut-out of the cold air and the plasma cabinets, cut-off valves are provided at the cold air pipeline, the inlets and outlets of each plasma cabinet; When a certain plasma cabinet needs to be taken out of operation, first stop the plasma power supply, then close the inlet valve of the plasma cabinet, and close the outlet valve of the plasma cabinet to complete the cut-out operation of the plasma cabinet; When a certain plasma cabinet needs to be put into operation, the following steps are completed for the operation of putting the plasma cabinet into operation: open the outlet valve of the plasma cabinet, open the cold air inlet valve of the plasma cabinet, and the plasma is powered on and enters the operation; The adjustment of the blast furnace air temperature can be carried out in two ways: one is to adjust the blast temperature by putting into and cutting out the working plasma cabinets; the other is to adjust the blast temperature by adjusting the cold air flow rate.

[0005] Through the above design, the plasma cabinet can be effectively utilized to heat and blast air, and the air temperature can be quickly and flexibly adjusted, achieving the goals of stable and smooth operation of the blast furnace and reduction of carbon consumption. 1. Using the plasma cabinet to heat the blast air of the blast furnace, the air temperature can reach over 1500 °C, realizing ultra-high air temperature smelting of the blast furnace, maximizing the utilization of electric energy, and reducing the demand of the blast furnace for fossil energy coal. 2. The adjustment speed of the blast furnace air temperature is fast, the adjustment range is large, the operation is simple, the floor area of the facilities is 60% less than that of the traditional blast furnace, and the one-time investment is reduced by 40%. 3. Using the plasma cabinet to heat the blast air of the blast furnace creates conditions for the traditional blast furnace ironmaking process to fully utilize green electricity metallurgy and minimize carbon consumption. This invention makes it possible for the traditional blast furnace to fully utilize clean energy to reduce carbon consumption and can be widely promoted and applied in the traditional blast furnace ironmaking process technology. Embodiment

[0006] A method for plasma heating of blast furnace air includes a heating device composed of several plasma cabinets connected in parallel. Under the action of a blower, cold air with a certain pressure and flow rate is transported through a cold air pipeline. Part of the cold air pipeline enters the plasma cabinet, and part of the cold air does not pass through the plasma cabinet. The cold air passing through the plasma cabinet is heated to over 2500 °C under the action of the plasma heating device and directly enters the unheated cold air pipeline to heat the cold air. Finally, the high-temperature blast air heated by the plasma cabinet is mixed with the cold air of the blower to form the high-temperature blast air required by the blast furnace and enters the blast furnace to participate in the combustion reaction; according to the air temperature requirement, 5 - 10 groups of 8MW plasma cabinets are added to heat the cold air; according to the production requirement, the air volume entering the plasma cabinet and the data of the plasma cabinets put into operation are determined. To facilitate the input and cut-out of the cold air and the plasma cabinets, cut-off valves are installed at the cold air pipeline and the inlets and outlets of each plasma cabinet; when a certain plasma cabinet needs to be taken out of operation, first stop the plasma power supply, then close the inlet valve of the plasma cabinet, and close the outlet valve of the plasma cabinet to complete the cut-out operation of the plasma cabinet; when a certain plasma cabinet needs to be put into operation, the plasma cabinet commissioning operation is completed according to the following steps: open the outlet valve of the plasma cabinet, open the cold air inlet valve of the plasma cabinet, and send power to the plasma to enter the operation; the adjustment of the blast furnace air temperature can be carried out in two ways: one is to adjust the blast air temperature by putting into and cutting out the working plasma cabinets; the other is to adjust the blast air temperature by adjusting the cold air flow rate.

Claims

1. A method for heating blast furnace air by plasma, comprising a heating device composed of a plurality of plasma cabinets connected in parallel, characterized in that: Under the action of the blower, cold air with a certain pressure and flow rate is transported through the cold air pipeline. A part of the cold air pipeline enters the plasma cabinet, and a part of the cold air does not pass through the plasma cabinet. The cold air passing through the plasma cabinet is heated to above 2500 °C under the action of the plasma heating device and directly enters the unheated cold air pipeline to heat the cold air. Finally, the high-temperature blast heated by the plasma cabinet is mixed with the cold air of the blower to form the high-temperature blast required by the blast furnace and enters the blast furnace to participate in the combustion reaction; according to the requirement of blast temperature, 5-10 groups of 8MW plasma cabinets are added to heat the cold air; according to the production requirement, the air volume entering the plasma cabinet and the data of the plasma cabinets put into operation are determined. To facilitate the input and cut-out of the cold air and the plasma cabinet, cut-off valves are installed at the inlet and outlet of the cold air pipeline and at the inlet and outlet of each plasma cabinet; when a certain plasma cabinet needs to be taken out of operation, first stop the plasma power supply, then close the inlet valve of the plasma cabinet, and close the outlet valve of the plasma cabinet to complete the cut-out operation of the plasma cabinet; when a certain plasma cabinet needs to be put into operation, the following steps are completed for the operation of the plasma cabinet: open the outlet valve of the plasma cabinet, open the cold air inlet valve of the plasma cabinet, and send power to the plasma to enter the operation; the blast temperature of the blast furnace can be adjusted in two ways: one is to adjust the blast temperature by putting into and cutting out the working plasma cabinets; the other is to adjust the blast temperature by adjusting the cold air flow rate.