Hot-rolled steel waste heat recovery system and waste heat recovery method based on phase change control

Abstract

The invention particularly relates to a hot rolled steel waste heat recovery system and method based on phase change control, the system comprises a salt bath, a fused salt pump, an evaporator, a deaerator and a water pump, a salt liquid outlet of the salt bath is connected with the evaporator through a first pipeline, the fused salt pump is arranged on the first pipeline, and a salt liquid inlet of the salt bath is connected with the evaporator through a second pipeline; the deoxidizing pump is connected with the evaporator through a third pipeline, the water pump is arranged on the third pipeline, and the evaporator is further connected with a fourth pipeline. The method comprises the steps that after hot-rolled steel enters a salt bath, heat is absorbed by salt liquid, after the salt liquid absorbs the heat, the temperature rises, the salt liquid is fed into an evaporator through a molten salt pump, forced circulation heat exchange is achieved between the salt liquid and treated water input into a deaerator through a water pump, and after heat exchange, the temperature of the salt liquid is reduced to the temperature needed by phase change of the steel, and the salt liquid is fed back to the salt bath; the hot-rolled steel is subjected to phase change in the salt bath, water exchanges heat with the salt liquid in the evaporator and then is converted into medium-pressure steam, and waste heat recycling is achieved.

Description

technical field [0001] The invention relates to the technical field of waste heat recovery of hot-rolled steel, in particular to a waste heat recovery system and method for hot-rolled steel waste heat recovery based on phase transition control. Background technique [0002] The carbon emissions of my country's iron and steel industry account for about 14% of China's total carbon emissions. The low-carbon, high-energy-efficiency and green development of the iron and steel industry is of great significance to the country's realization of the dual-carbon goal. For long-process iron and steel enterprises, about 34% of the energy input into the process is converted into various types of waste heat. Most processes in the long-process iron and steel industry, such as sintering, coking, ironmaking, and steelmaking, have relatively mature technical solutions for waste heat recovery, but there is no ideal recovery method for the waste heat resources contained in hot rolling processes,...

AI Technical Summary

Problems solved by technology

If we simply recycle the remaining heat resources and ignore the product performance of steel, it is obviously putting the cart before the horse and cannot be implemented.

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