Raw gas high-temperature residual heat recovery method and device

Abstract

The invention relates to a raw gas high-temperature residual heat recovery method and device. The method includes the following steps that raw gas is introduced into all waste heat recovery rising pipes, a circulating water pump is connected with a steam pocket, a water outlet of the circulating water pump is connected with a water supply main pipe, the water supply main pipe conveys water to pipewater heat removal device water inlets of all rising pipe wall heat removal devices, the water converges to a water return main pipe through a plurality of parallel-connection water return branch pipes after coming out of pipe water heat removal device water outlets of all the rising pipe wall heat removal devices, the water return main pipe conveys the water to the steam pocket, saturated steamseparated from the top of the steam pocket is sent into a steam supply main pipe, and the steam supply main pipe conveys the saturated steam to inner heat removal device steam inlets of all rising pipe inner heat removal devices through a plurality of parallel-connection steam supply branch pipes. All the rising pipes are used for producing high-pressure saturated steam, the produced high-pressuresaturated steam can be sent back to the rising pipe inner heat removal devices to produce overheat steam, and the raw gas residual heat recovery efficiency can be improved to the maximum extent.

Description

technical field [0001] The invention relates to a method and a device for recovering waste heat from raw gas at high temperature, which are mainly used for recovering waste heat from raw gas in coke ovens, and belong to the technical field of thermal engineering and energy saving (boiler). Background technique [0002] Multiple coking coals in the coke oven are heated and dry-distilled by isolated air to generate coke. At the same time, a large amount of volatile matter is volatilized to produce raw coal gas. The coke oven has multiple dry distillation chambers (carbonization chambers) arranged side by side, and each carbonization chamber is There are one or two ascending pipes, and the dry distillation in the carbonization chamber is as high as 850°C. The sensible heat accounts for about 36% of the coke oven expenditure heat. After the ammonia water is vaporized, the temperature of the raw gas is quickly reduced to about 80°C. The high-temperature heat of the raw gas is was...

AI Technical Summary

Problems solved by technology

[0004] 1. Any waste heat recovery method does not solve the problem of recovering high-temperature waste heat from the high-temperature raw gas beyond the boundary layer of the wall end of the heat extractor inside the riser, that is to say, the current waste heat recovery from raw gas only recovers the boundary of the waste heat recovery heat exchanger The heat of the raw gas in the part of the thickness of the boundary layer, and the heat of the raw gas in the part of the area beyond the thickness of the boundary layer is not and cannot be recycled;

[0005] 2. It is not possible to produce superheated steam at the same time that all the risers are used to produce saturated steam. If it is necessary to produce superheated steam, stop part of the riser to produce saturated steam and replace it with superheated steam, which makes this part less efficient and more wasteful. The waste heat of raw gas that should have been recovered makes the efficiency of waste heat recovery of the inefficient riser pipe even lower;

[0006] 3. When the raw gas is lower than 450°C, it starts to coke, which will bring hidden dangers to production safety;

[0007] 4. High-temperature raw gas has severe high-temperature corrosion, and metals exposed to raw gas will cause rapid high-temperature corrosion;

[0008] 5. The waste heat recovery of the rising pipe of raw gas can only produce low-medium pressure steam, so that the high-quality waste heat of raw gas can only be recycled with low quality, which wastes the energy efficiency of high-quality waste heat of raw gas, which is a waste of high-quality waste heat resources of raw gas Recycle

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