Reverse immersion method normal pressure hot-smouldering steel slag and waste heat recovery system and method

Abstract

The invention relates to a reverse immersion method normal pressure hot-smouldering steel slag and waste heat recovery system. The system comprises a slag smouldering device and a waste heat recovery device connected with the slag smouldering device. The slag smouldering device comprises a solid slag tank, a water supply and drainage device communicated with the bottom of the solid slag tank and a water-cooling dust collecting cover arranged above the solid slag tank; the waste heat recovery device comprises a waste heat boiler connected with the water-cooling dust collecting cover through a water-cooling flue; a low-temperature flue gas pipeline of the waste heat boiler is communicated with a spray tower, a dehydrator, a wet type electronic dust removal tower, a dust removal fan and a purified gas discharge tower which are connected in sequence; the dust removal fan is dragged by a steam turbine; and a saturated steam pipeline of the waste heat boiler is connected with the steam turbine. The invention further relates to a method for slag smouldering and waste heat recovery through the system. According to the system and method, the temperature of the steel slag entering the tank can be increased, waste heat of the hot steel slag is fully utilized, meanwhile, combustible gas generated in the slag smouldering process is effectively treated and recycled, and the safety and energy conservation are achieved.

Description

technical field [0001] The invention relates to a system and method for recovering hot stuffy steel slag under normal pressure and waste heat by reverse immersion method. Background technique [0002] Steel slag is a by-product in the steel smelting process, and its output is about 12% to 14% of crude steel output. At present, the annual output of steel slag in my country has reached about 150 million tons. Steel slag contains a certain amount of iron metal elements, and the recovery of metallic iron has huge economic value for metallurgical enterprises. Steel slag also contains a large amount of unstable substances such as free magnesia (f-MgO) and free calcium oxide (f-CaO). The characteristics of severe expansion of the volume of the reaction with water are not conducive to the recycling of steel slag. The temperature of liquid steel slag is as high as 1400~1600°C, which has relatively high waste heat recovery value. [0003] Hot stuffy steel slag is the main method of ...

AI Technical Summary

Problems solved by technology

[0010] 2. Tank type pressure hot stuffy

Second, the temperature of the steel slag loaded into the slag tank is too high, and the CO and H produced by the water in the water injection process 2 Combustible gases such as flammable gases are easy to gather to a certain concentration in a closed container, and the temperature reaches the ignition point of flammable gases and produces an explosion.

At the same time, the water temperature in the autoclave has a temperature difference from top to bottom, and the slag stuffing effect is uneven, especially in large-volume slag tanks.

[0016] (v) The steam generated by the slag contains a large amount of combustible gases such as hydrogen and carbon monoxide and particulate matter, which is difficult to collect and utilize

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