Waste heat recovery device for blast furnace slag flushing water

Abstract

The invention provides a waste heat recovery device for blast furnace slag flushing water.The waste heat recovery device comprises a slag water pool, a slag water variable-frequency pump, a heating variable-frequency pump, a heating device, a controller, a first heat exchanger and a second heat exchanger.The slag water pool is connected to the first heat exchanger and the second heat exchanger, the first heat exchanger and the second heat exchanger are communicated with the slag water variable-frequency pump through slag water pipes and are communicated with the heating device through heating water pipes, control valves are arranged at the connecting positions of the first heat exchanger and the slag water pool, the slag water variable-frequency pump, the heating variable-frequency pump and the heating device, and control valves are arranged at the connecting positions of the second heat exchanger and the slag water pool, the slag water variable-frequency pump, the heating variable-frequency pump and the heating device.A controller controls the control valves to be switched on or switched off, the two heat exchange devices are connected in parallel, and the working speed of the water pumps is automatically adjusted according to temperature changes.In this way, the waste heat recovery device can be synchronous with the slag flushing period, production energy consumption can be greatly reduced, and production cost can be greatly lowered.

Description

technical field [0001] The invention relates to the field of blast furnace slag flushing heat recovery, in particular to a blast furnace slag flushing waste heat recovery device. Background technique [0002] Blast furnace is a kind of steelmaking equipment, which uses steel plates as the furnace shell, and refractory bricks are laid on the inner wall of the furnace. During smelting, iron ore, fuel and solvent are poured into the blast furnace from the furnace mouth, and the oxygen in the iron ore is extracted by heating to obtain iron, and finally the molten iron is discharged out of the furnace. [0003] In the above smelting process, the main product produced is pig iron, and a by-product called blast furnace slag is produced at the same time. Blast furnace slag is extracted with water to make blast furnace slag water. As a low-temperature waste heat source, it has the characteristics of stable temperature and large flow rate. Therefore, how to recover and utilize the wa...

AI Technical Summary

Problems solved by technology

However, the amount and flow of slag washing water produced by blast furnace steelmaking are large, and the heat contained in it is also large, while the heat required for indoor heating is limited. , there is no effective way to recycle

Therefore, the existing technology provides a way of driving the heat exchanger to work through the high-speed operation of the water pump, exchanging heat with the slag washing water and recovering its heat. In actual use, due to the periodicity of blast furnace smelting, the extraction of blast furnace slag produces blast furnace slag. The process of flushing slag water is also periodic. When the blast furnace is not flushing slag, the temperature of the slag flushing water is low. If the water pump is kept running at high speed, it will cause a lot of waste of energy.

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