Electric heating atmospheric pressure reaction kettle can be divided into carbon steel reaction kettle, stainless steel reaction kettle, and enamel glass reaction kettle (enamel reaction kettle) according to the material. According to the manufacturing structure of the reaction vessel, it can be divided into three categories: open flat cover reaction vessel, open butt welded flange reaction vessel, and closed reaction vessel. Each structure has its own scope of application and advantages and disadvantages.