Which heating method is the fastest in pickling solution?

In the manufacturing process of condenser tube, the surface oxides produced by hot rolled steel strip during hot rolling need to be removed before cold rolling. At present, the method of removing these oxides is high-temperature hydrochloric acid pickling, which has good effect. The commonly used hydrochloric acid heating method is mostly steam heating method. These high-pressure and high-temperature steam are produced by coal-fired or gas-fired boilers, which will bring a lot of waste gas pollution. Moreover, steam is used for one-time heating, and the discharge of waste water with residual heat will also cause water pollution. In addition, there is a hydrochloric acid heating device, which adopts the following methods, for example, the patent publication number is CN105188171A, and is mainly composed of a quartz tube, a heating source, a heating fixing seat and a safety shield. The open end of that quartz tube is provided with a heating fix seat and a safety cover, a heat source is arranged in the quartz tube, the quartz tube and the heat source are fixed through the heating fix seat, and the end of the heat source is provided with a safety cover; The heating method is to put the quartz tube into hydrochloric acid, and the heating source in the quartz tube is below the liquid level of hydrochloric acid to prevent dry burning. The quartz tube does not react with hydrochloric acid and is not in direct contact with hydrochloric acid. Another example is the internal heating hydrochloric acid heating device with the patent announcement number of cn86204 145u, which is an energy-saving device applied to the production of existing reagent hydrochloric acid. A spiral heater consisting of a protective sleeve and a heating element is used for heating under the liquid surface, and the outer protective sleeve is an oil-immersed resistance heater with a glass tube. These resistance heaters are placed in hydrochloric acid liquid, and even the best protective cover is not 100% safe, and its heat transfer effect is also poor after passing through the protective cover.