Blast furnace slag dry-type sensible heat recovery system and production process

Abstract

The invention provides a blast furnace slag dry-type sensible heat recovery system and a production process. The production process comprises a slag tundish heat preservation process, a spray gun slag spraying process, a slag multiple jet flow granulation heat exchange process, an impact grinder grinding process and a double-cooling fluidized bed heat recovery process. After being subjected to nitrogen blowing saturated treatment in the tundish, the blast furnace slag is sprayed out by a high-speed air flow spray gun, high-speed air flow slag grains impact one another to be granulized in a jet flow mill, forced heat exchanged is performed, the slag grains move downward and are rebounded and crushed by a flat plate impact grinder, and the crushed slag grains are subjected to heat exchange and cooling; and a double-cooling fluidized bed is used for recovery the heat of the slag grains for a second time, and the heat recovered at the first time and the heat recovered at the second time are converted into heat energy or electric energy by a heat exchanger. When the system and production process of the invention are used, the heat recovery rate of the blast furnace slag reaches more than 80 percent; the finished slag yield is more than 90 percent; the granularity is less than 5 millimeters; the system does not use cooling water in a whole process; and the dry-type treatment saves a large amount of water.

Description

Technical field: [0001] The invention belongs to the technical field of waste heat and waste energy recovery, and in particular relates to a blast furnace slag dry-type sensible heat recovery system and a production process. Background technique: [0002] The sensible heat of blast furnace slag is a high-grade waste heat resource with high recovery value. At present, most iron and steel enterprises use water quenching process to treat blast furnace slag, and the sensible heat of slag is basically not recovered. With the increasingly intensified international competition and the continuous shortage of energy, the iron and steel industry is facing many environmental-friendly issues to maintain sustainable development strategies. Among them, efficient and high-grade recovery of sensible heat from blast furnace slag has become an urgent technical problem. [0003] US Patent No. 5,255,900 reports a related design method of a granulator and a fluidized bed for recovery of slag w...

AI Technical Summary

Problems solved by technology

However, due to the limitations of the huge equipment system, large floor area, high investment cost and excessive energy loss in the system process, the progress was stopped at that time.

[0006] According to the analysis of existing technical data, most of the current processes have problems such as low heat transfer efficiency, large particle size of finished slag, and huge equipment.

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