A biomass hot gas boiler used for disinfection and concentration of fluid or semi-fluid products. It includes a furnace body, a furnace bladder and a flue. The mouth of the pipe is connected, and the lower port is communicated with the air supply pipe below the furnace liner; a safety valve is arranged on the upper part of the furnace liner; the stirring tube extends from the upper part of the furnace liner, and the lower pipe mouth is located at the inner bottom of the furnace liner.

Due to the adoption of the above-mentioned solution, the disinfection and concentration treatment time of the fluid or semi-fluid product is short, and the efficiency is high; and the loss of nutrients is small; the semi-fluid product will not cause agglomeration and carbonization, and the quality of the product is improved.