The biomass thermal oil furnace series organic heat carrier furnace is an assembled forced circulation vertical biomass thermal oil furnace. The heating surface structure of this series of boilers is compact, consisting of inner and outer tightly arranged circular tubes. The inner tube is a radiative heating surface, while the outer and inner tubes form a convective heating surface. The biomass thermal oil furnace consists of an upper body and a lower combustion chamber, which are assembled on site. After the fuel is fully burned in the combustion chamber, most of the heat is absorbed by the radiant heating surface, and the high-temperature flue gas enters the convective heating surface for heat exchange. The flue gas generates material and conducts heat through the oil furnace, heating the air required for boiler combustion in the air preheater. Then, the flue gas is sent to the chimney by the induced draft fan through the dust collector and discharged into the atmosphere. All types of emission indicators are lower than the national (GB13271-2001) "Emission Standards for Air Pollutants from Biomass Thermal Oil Boilers", making it the best product to replace electric, fuel oil, gas, and coal-fired steam boilers. Biomass boilers have low operating costs, saving 40% -60% compared to oil, gas, and electric heating boilers, and 5% -10% compared to coal-fired boilers. They are an efficient, energy-saving, and environmentally friendly thermal energy equipment.