Off-line drying-out method of hot-blast stove

Abstract

The invention provides an off-line drying-out method of a hot blast stove, and relates to the technical field of hot blast stove maintenance. The off-line drying-out method of the hot blast stove comprises the steps that a first pipeline is laid between a first manhole and a chimney, a drying-out burner is arranged in a second manhole, and a second pipeline is laid between the drying-out burner and a gas main pipe; and a gas inlet, a combustion-supporting gas inlet and a waste gas exhaust port of the hot blast stove are closed and a combustor of the hot blast stove is shutdown, gas is conveyedto the drying-out burner through the second pipeline, combustion-supporting gas is conveyed to the drying-out burner through an access hole or a combustion-supporting gas pipeline, the combustion-supporting gas and the gas are mixed and combusted in the drying-out burner, generated waste gas is conveyed to the chimney through the first pipeline, and the heating rate of the hot blast stove is controlled to be 1 - 4 DEG C / h by adjusting the gas inlet rate of the gas and the combustion-supporting gas and the exhaust rate of the waste gas. According to the drying-out method, the to-be-repaired hot-blast stove can be independent from a hot-blast stove system, and the heating rate of the hot-blast stove is strictly controlled, so that the situation that silica bricks at a high-temperature partof the hot-blast stove are damaged and collapsed in the drying-out process is prevented.

Description

technical field [0001] The present application relates to the technical field of hot blast stove maintenance, and in particular, relates to an off-line oven drying method of a hot blast stove. Background technique [0002] In the on-line emergency repair of silica brick hot blast furnace, the temperature control of the furnace is highly required, especially before 700°C, the temperature rise is usually controlled at 2-3°C per hour. If the existing air and gas system of the hot blast stove is used for baking, since the combustion valve and the shut-off valve are both gate valves, the regulating valve (butterfly valve structure) also has a certain leakage rate like the gate valve, and the temperature control accuracy effect cannot reach the baking temperature. A small increase in temperature in the furnace is required. [0003] The same waste gas valve also has a certain leakage rate. In the early stage of the oven, because the amount of flue gas generated is very small, if t...

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Problems solved by technology

[0003] The same waste gas valve also has a certain leakage rate. In the early stage of the oven, because the amount of flue gas generated is very small, if the flue valve is opened to discharge waste gas, the amount of waste gas in the flue main pipe (normally fired by 2 or more hot blast stoves) is greater than If the exhaust gas volume of the oven cannot achieve a good negative pressure effect, the exhaust gas in the flue main pipe will be poured into the hot blast stove of the oven, resulting in the failure of the oven.

If in order to ensure a good negative pressure state in the flue main pipe, it is necessary to fully open the waste heat recovery flue bypass valve, but it will cause the temperature of the air and gas to drop significantly after preheating, which will affect the normal firing and air temperature of the hot blast stove, and the gain outweighs the gain

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