Acheson furnace with furnace core waste heat extraction function and furnace group energy-saving and efficiency-improving method

The invention discloses an Acheson furnace with a furnace core waste heat extraction function and an energy-saving and efficiency-improving method of a furnace group, and relates to the technical field of Acheson furnace graphitization. The lower portion of the micro-oxygen gas bottom blowing device is respectively connected with a micro-oxygen gas header pipe, a heat energy transfer header pipe and a nitrogen header pipe through a distributor, the distributor is respectively connected with a furnace inner bottom blowing device through elbows and valves, and the U-shaped air return devices are arranged in furnace walls on two sides and resistance materials below a furnace bottom crucible. Insulating high-temperature-resistant tee joints are installed on the furnace wall faces on the two sides of the U-shaped air return device, removable flue type furnace covers are arranged on the furnace walls on the two sides, high-temperature heat storage devices are arranged at furnace heads of the removable flue type fur