What are the methods to improve the thermal efficiency of heating furnaces?

1) Maintain complete combustion； 　 (2) While ensuring complete combustion, reduce the excess air coefficient and adjust the three doors and one plate appropriately ； 　 (3) Operate smoke gas waste heat recovery facilities such as air preheaters and waste heat boilers properly ； (4) Strengthen equipment management; ensure the furnace body is airtight, preventing cracks or collapses in the refractory layer of the furnace walls, and maintain its integrity at all times. Reduce air leakage into areas such as the lower elbow boxes, manholes, and sight glasses, thereby minimizing heat loss. The exposed sections (including those subject to convective radiation and the lower elbow areas) need to be properly insulated to prevent excessive heat loss ； 　 (5) Prevent coking of furnace tubes ； 　 (6) Enhanced soot blowing in the convection chamber (for fuel oil-fired heaters), as well as burning of carbon deposits and cleaning of salt scale during major overhauls of the radiation chamber, to improve heat transfer efficiency.