Preparation method of sodium tungstate solution and method for recovering alkaline in preparation process

The invention discloses a preparation method of a sodium tungstate solution and a method for recovering an alkaline in a preparation process. The preparation method comprises the following steps: adding water into tungsten ores to be ground into tungsten ore pulp and adding a NaOH solution to obtain mixed slurry; feeding the mixed slurry into a reaction kettle for alkali autoclaving to obtain alkali autoclaving slurry, and filtering the alkali autoclaving slurry to obtain a feed liquid; feeding the feed liquid and pure water into an ionic membrane diffusing dialyzer to be diffused and dialyzed to obtain the sodium tungstate solution and a diluted NaOH solution; feeding the diluted NaOH solution into an electrodialyzer to be treated to obtain a concentrated NaOH solution and desalted water; returning and using the concentrated NaOH solution which is regulated to a set concentration, and returning the desalted water for receiving NaOH of the ionic membrane diffusing dialyzer. The method disclosed by the invention is used for realizing separation of the sodium tungstate solution and alkali liquor under a normal temperature and normal pressure condition and is low in energy consumption, easy to operate and realize, and the use amount of alkaline in the production process can be reduced.