Apparatus for continuously producing potassium sulfate

An apparatus for the production of potassium sulfate and hydrogen chloride gas from potassium hydrogen sulfate and potassium chloride, comprising:

• (a) an elongated horizontal type muffle furnace having an arcuate heat-conductive upper wall, said furnace having (i) at least one elongated and horizontally disposed agitator shaft which is equipped with agitating blades that are adapted to admix the reaction mixture therein rapidly by agitating and turning over said mixture so as to prevent it from adhering to the bottom of the furnace,
• (ii) a raw material feeder located in a first end wall of said elongated furnace, said raw material-feeder extending inwardly into the furnace to a point which is located between the longitudinal center of the furnace and said first end wall,
• (iii) a reaction product-discharging means located in a second end wall that is opposite from said first end wall, said reaction product-discharging means being located on a level higher than that of the axial center of said at least one agitator shaft,
• (iv) an exit port in the furnace for the removal of hydrogen chloride gas generated,
• (v) the agitating blade closest to the wall surface of the furnace which contains said reaction product-discharging means being positioned in close contact with said inner wall surface so as to be able to scrape the reaction mixture off said wall surface, and
• (b) an outer casing surrounding said muffle furnace, in which casing said furnace is supported on a bed of an insulating material and the casing is spaced away from the top of the furnace to thereby form a passage for heating gas which provides the amount of heat necessary to complete the total reaction, said heating space over said furnace having an inlet port for introducing heating gas and an outlet port for the removal of heating gas, a drop arch type partititon wall being provided in the vicinity of said outlet port for exhaust gas.