Water tank is a kind of physical and chemical reaction vessel. Belong to the mixing equipment. Material is put inside the kettle, while working in the jacketed ventilation with different heat conduction medium (freezing liquid, hot water or hot oil) circulation of heating or cooling, by heating or cooling jacket heat conduction medium material inside the kettle in constant temperature, heating or cooling, at the same time, according to the requirement under the condition of atmospheric pressure or negative pressure for stirring, so as to speed up the material within the kettle reaction, and can control the material evaporation and backflow. After the reaction material from the kettle bottom discharging mouth out.