Multi-tank type sensible heat recovery device and method for sintered ore

Abstract

The invention discloses a multi-tank type sensible heat recovery device and method for sintered ore. The method includes the steps that a sintered ore material is fed into a multi-tank type sensible heat recovery assembly from a sintered ore conveying belt arranged at the bottom of a sintered ore storage bin after being smashed, and the multi-tank type sensible heat recovery assembly screens the sintered ore material according to the ore material particle sizes and then feeds the sintered ore material into different vertical tank cooling devices; the sintered ore material descends at a constant speed in the vertical tank cooling devices after being evenly distributed; the sintered ore material and air blowing devices are subjected to air blowing heat exchange in the descending process; the sintered ore material is discharged out of pipelines in all the vertical tank cooling devices by warmed hot-blast air in the air blowing heat exchange process; the sintered ore material passes through a dust removal device after being gathered and then enters a sensible heat recovery device body; and low-temperature exhaust gas subjected tosensible heat recovery passes through a gas circulation assembly and then is fed into the air blowing devices at the lower sides of the insides of the vertical tank cooling devices, and accordingly sensible heat recovery and gas cyclic utilization are realized. The multi-tank type sensible heat recovery device and method are suitable for the field of sintered ore sensible heat recovery in various types of ferrous metallurgy production.

Description

technical field [0001] The invention relates to a sensible heat recovery device and a sensible heat recovery method, in particular to a sensible heat recovery device and a sensible heat recovery device for recovering the sensible heat of sintered ore in the field of iron and steel metallurgy production in a multi-tank combination mode for high-temperature block materials Recycling method. Background technique [0002] At present, in various iron and steel metallurgical enterprises in my country, a kind of sintered ore is widely used as the main charge of blast furnace ironmaking. The annual national sinter output is about 850 million tons. The energy consumption of the sintering process accounts for about 12% of the total energy consumption of steel production, of which the waste heat of sintering waste gas accounts for about 4%, and the sensible heat of sintering ore accounts for about 8%. Therefore, the waste heat resources in the sintering process, especially sintering or...

AI Technical Summary

Problems solved by technology

[0004] The low-temperature waste gas produced in the cooling process of sinter in the prior art mainly utilizes sensible heat resource methods such as waste heat boiler and power recovery, hot air sintering recovery, hot air ignition combustion-supporting recovery, and preheating raw material recovery. The overall waste heat utilization rate is less than 30%, while in foreign countries this ratio is as high as 50-80%. The gap is self-evident, so the waste heat recovery potential of the sintering process is still great

[0005] Feedback from on-site operators and long-term records and analysis of various sampling equipment show that the sensible heat recovery efficiency of the traditional blast ring cooling or belt cooling process of sinter under the existing technology is not high, and the overall waste heat utilization rate is insufficient. It is due to the following disadvantages:

[0008] (3) The belt cooler or annular cooler of the prior art has the disadvantages of its average floor area and large volume, high investment, high energy consumption, large dust in the area, and heavy equipment maintenance workload.

However, the reasons why the technology is difficult to apply in engineering are:

[0012] (1) The amount of sintering waste gas is large, and when the gas-to-material ratio (the ratio of gas volume to sinter mass) is too large, the temperature rise of the gas after heat exchange is limited, and it is difficult to meet the requirements of the follow-up waste heat power generation system for the smoke temperature;

[0013] (2) The negative pressure of the sintering waste gas from the main flue is as high as 15000Pa, and then boosted to overcome the resistance of the material layer in the shaft furnace, which puts forward very strict requirements on the fan, resulting in a sharp increase in fan power;

[0014] (3) SO in sintering waste gas 2 High concentration and contains SO 3 , HCl, HF and other corrosive components, which will directly enter the waste heat boiler without treatment, will cause serious equipment corrosion

[0019] (1) The size of sinter varies, and the time required for cooling varies. Under the same gas-to-material ratio, the cooling process is uneven, and large pieces that are not completely cooled inside are easy to burn out the cold ore transfer belt after being discharged from the system;

[0020] (2) The sinter particles that are too small or too large are easy to form a dense gradation structure during the downward process in the shaft furnace, and may even be sintered again, resulting in excessive material layer resistance. The circulating cooling air system must choose a high-pressure fan, and then The energy consumption of the vertical tank cooling process is too large, which violates the original intention of the vertical cooling process to save energy;

[0021] (3) When thermal sintering of the material layer or material distribution / discharge failure occurs in the vertical tank, the operation mode of a single vertical tank will cause the shutdown of the entire system;

[0022] (4) A single vertical tank undertakes cooling of hot ore, which will result in a higher layer of material in the vertical tank and a larger area, which will bring challenges to the selection and design of equipment for material distribution, material discharge, air distribution, and air discharge

[0023] To sum up, the waste heat recovery device and recovery method of sinter in the prior art more or less have some deficiencies, so now there is an urgent need for a new type of multi-tank sensible heat recovery device for sinter and The sensible heat recovery method can make up for the shortcomings of the existing ring cooler or belt cooler to recover the sensible (waste) heat of sinter, and can make up for the shortcomings of the existing vertical cold recovery of sinter sensible heat device and process method

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