Method for producing phosphoric acid with vertical flaming kiln

The invention relates to a method for generating phosphoric acid by using a vertical open flame furnace and a device thereof. The method comprises the following steps: adding prepared ball materials and grainy solid fuels in the vertical open flame furnace from the upper part; causing the ball materials and the fuels to move downwards according to self-gravity during the continuous discharging process at the lower part of the furnace; burning the fuels to add the ball materials, so that the ball materials is gradually warmed up to 1200 to 1550 DEG C; oxidizing phosphoric vapor generated by reaction and carbon monoxide after being emitted into phosphorus pentoxide and carbon dioxide in the weak oxidation atmosphere in a material channel; and spraying and absorbing with circulating acid to obtain the high concentration phosphoric acid. The method for generating the phosphoric acid by using the vertical open flame furnace is another feasible route except for tunnel kiln-method phosphoricacid and revolving kiln-m