Method for calculating flash evaporation rate of flash evaporation process in alumina evaporation process

The invention provides a method for calculating a flash evaporation rate of a flash evaporation process in an alumina evaporation process, and relates to the technical field of industrial automatic control application. The steps of the invention are as follows: step 1: obtaining real-time process data of an alumina evaporation system; step 2: determining whether the feed amount of the flash evaporation system is in the normal working range of 450 m3/hr to 650 m3/hr, if so, proceeding to step 3 and if not, executing step 1; step 3: obtaining the boiling point rise [delta]'BPE of a sodium aluminate solution according to the data obtained in step 1; and step 4: calculating the flash evaporation rate CFS according to the boiling point rise [delta]'BPE obtained in step 3, and evaluating the flash evaporation intensity of actual alumina production in real time based on the obtained CFS online. The method of the invention evaluates the flash evaporation intensity of the flash evaporator online, and has important sig