A recovery device and working method for recovering waste heat of high-temperature liquid blast furnace slag

Abstract

The invention discloses a recovery device used for recovery of high-temperature liquid-state blast furnace slag waste heat. The recovery device comprises a granulating device and a gas-solid heat exchange device. The granulating device comprises a box body structure and a granulating disc arranged in the box body structure. The granulating disc is connected with a drive motor on the outer portionof the box body structure through a worm and worm gear. A molten slag inlet is arranged on the upper portion of the box body structure and is provided with a slag flow controller. The upper portion ofthe left side of the box body structure is covered with a high-temperature gas collecting hood exposed out of the molten slag inlet. The high-temperature gas collecting hood is connected with the left end of the gas-solid heat exchange device through a gas conveying pipe. A slag granule discharging opening is arranged on the lower portion of the box body structure and is connected with the rightend of the gas-solid heat exchange device through a slag granule collection hopper. An air inlet pipe is arranged on the side wall of the lower portion of the box body structure and provided with an air inlet controller. According to the recovery device, slag drops can be cooled fast to form a glass phase microstructure, recovery of heat of high-temperature liquid-state molten slag can be achievedto the maximum extent, and resource utilization and energy utilization of the high-temperature liquid-state molten slag can be achieved.

Description

technical field [0001] The invention relates to the technical field of energy utilization in the iron and steel industry, in particular to a recovery device and working method for recovering high-temperature liquid blast furnace slag waste heat. Background technique [0002] Blast furnace ironmaking is the link with the highest energy consumption in the iron and steel industry, and maximizing energy conservation and emission reduction is the basic requirement for the healthy development of the current iron and steel industry. During the blast furnace production process, the high-temperature liquid blast furnace slag, a by-product directly discharged from the blast furnace, has a temperature as high as 1500°C or more. At present, the subsequent treatment of high-temperature liquid blast furnace slag in China is water quenching. During the water quenching process of high-temperature liquid blast furnace slag, not only a large amount of fresh water is consumed, but also SO 2 、...

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Problems solved by technology

The process flow is as follows: when the molten slag flows into the granulation device vertically from the intermediate slag tank, under the action of surface tension, it shrinks into a nearly standard cylindrical shape; The high-speed rotation, under the action of centrifugal force, gradually thins out into a circle, forms a film, and quickly covers the upper surface of the granulation disc; , broken into filaments, and then the slag filaments are broken into several sections; each section of slag filaments shrinks into balls under the action of surface tension, forming slag droplets; during the flight, the slag droplets run against the surrounding air at high speed, generating severe heat Radiation and heat conduction, while the slag droplets are rapidly cooled, the ambient temperature in the granulation device rises sharply; the increase in the ambient temperature will seriously reduce the cooling rate of the slag droplets, and the slag droplets that cannot be cooled rapidly During the evolution process, it is difficult to form a glass phase microstructure, and most of the slag particles cannot be used as raw materials for the subsequent cement industry, so it will make the dry centrifugal granulation technology meaningless in the subsequent treatment process of high-temperature liquid blast furnace slag

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