Boric acid production method and device of boron-containing brine

The invention provides a boric acid production method of boron-containing brine, which comprises the following steps of: adding alkali into the boron-containing brine to adjust the pH value, feeding into a resin adsorption device to complete an adsorption period, adding hydrochloric acid and pure water for desorption, forming a dilute boron desorption solution in the form of boric acid, and feeding into an evaporation and concentration process, a dilute boron desorption solution is firstly heated by a heat source through a preheater and enters a multi-stage membrane evaporation device to evaporate a large amount of water, a concentrated solution is discharged into a buffer tank and then is pumped into the preheater through a material transfer pump to be heated, the concentrated solution enters a flash crystallizer, and boric acid crystals are separated out at the bottom of the flash crystallizer. According to the flash evaporation crystallizer, heat is transferred step by step, the next stage obtains heat to