Waste heat recycling method and device of full-hydrogen hood-type annealing furnace

Abstract

The invention relates to a waste heat recycling device of a full-hydrogen hood-type annealing furnace. The waste heat recycling device is characterized in that a steam waste heat boiler, a hot water waste heat boiler and a magnetic driving leakproof fan are connected in sequence through hydrogen circulating pipes and then are connected to an inner hood of the full-hydrogen hood-type annealing furnace; high-temperature gas butterfly valves are respectively arranged on the hydrogen circulating pipes except between the two boilers. The steam waste heat boiler and the hot water waste heat boiler which are connected in series are arranged, so that high-temperature hydrogen in the full-hydrogen hood-type annealing furnace is cooled through heat exchange and then flows back to the full-hydrogen hood-type annealing furnace, heat in the full-hydrogen hood-type annealing furnace is fully used, energy conservation and emission reduction are realized, and the production cost is reduced; additionally, after the temperature of the high-temperature hydrogen is reduced through heat exchange, the high-temperature hydrogen flows back to the inner hood so as to perform heat convection on a strip steel coil in a cooling section, so that the cooling speed of strip steel is obviously increased, the furnace occupied time is reduced, the production efficiency is improved, expenses of enterprises are saved, and good economic benefits and social effects are obtained.

Description

technical field [0001] The invention relates to a waste heat recovery comprehensive utilization method and device. Background technique [0002] Annealing is a common process for producing high-quality cold-rolled strip steel and eliminating the internal stress of the strip steel. Bell-type annealing furnaces are generally used to anneal cold-rolled strip steel coils. A complete annealing process includes: furnace base cleaning → furnace base loading (steel coil + convection plate) → input annealing parameters → fasten the inner cover → lock the inner cover → cold seal inspection → nitrogen purging → start the circulation fan → buckle Put the heating cover→fill hydrogen (H2) protection→ignite the heating cover→heat up according to the set rate→change the fan to high-speed operation according to the control method→keep warm→heat seal check (before the heat preservation is over)→lift the heating cover and put on the cooling cover →Fan cooling to the set temperature→Spray wate...

AI Technical Summary

Problems solved by technology

A complete annealing process includes: furnace base cleaning → furnace base loading (steel coil + convection plate) → input annealing parameters → fasten the inner cover → lock the inner cover → cold seal inspection → nitrogen purging → start the circulation fan → buckle Put the heating cover→fill hydrogen (H2) protection→ignite the heating cover→heat up according to the set rate→change the fan to high-speed operation according to the control method→keep warm→heat seal check (before the heat preservation is over)→lift the heating cover and put on the cooling cover →Fan cooling to the set temperature→Spray water cooling to the furnace temperature→Nitrogen blowing→Hanging away the cooling cover→Loosen the lock of the inner cover→Hanging away the inner cover→Unloading→Save the annealing data, due to the current bell annealing furnace It basically replaces the previous conventional nitrogen-hydrogen protective gas (nitrogen-hydrogen protective gas, generally refers to 2-4% H2, 96-98% N2), and uses all-hydrogen protective gas. Therefore, after the traditional annealing process is completed, The hydrogen used for the protective atmosphere has a high temperature and is cooled with the strip steel in the subsequent cooling stage. Although there is indirect heat transfer from the inner cover to the cold air outside the inner cover, the cooling efficiency is high and a lot of energy is wasted at the same time.

Images