But there are also requirements

The method of production of boric acid can be divided by a method of treatment on and a two-level method with one step. The method with one step is used, inorganic acids directly consider containing pine forest a mineral. From which including sulfuric acid, hydrochloric acid, a nitric acid method. Now the Chinese industry of acid of pine forest, mainly, is used a sulfuric acid method. The two-level method is based on sulfuric acid, hydrochloric acid, nitric acid pleasure industrial the drill of decahydrate of the drill or pentahydrate drill to prepare boric acid in what the sulfuric acid method was earlier production accepted in China. In recent years nitric the drill of consideration of decahydrate acid and pentahydrate drill to make boric acid, process of a method of nitrate of nitrate of the sodium developed quickly and, Chinas steel important two-level process for boric acid. Sulfuric acid as devices for the decomposition, considering minerals of pine forest one process of a step, advantage - mature technology, process is simple, less investments in the equipment, easy operation. Therefore, long was exposed to attention of the people. But there are also requirements for higher level, not suitable to process low-grade pine forest; serious corrosion of the equipment; product quality control in big restrictions, pine forest with a poor harvest. Shortage of a reliable method of use of liqueur, make a greater impact on environment and other inconveniences.

The lake inTibet, China, contains many from drills and boric acid. The drill - the most important compositions of pine forest. In welding metal it will be with brown to clean a metal surface.