Production device and preparation method of alkalescent low-sodium salt in deep well

The invention provides a deep well alkalescence low sodium salt production device and a preparation method thereof.The deep well alkalescence low sodium salt production device comprises a plurality of membrane filters and a K-type tank group, the K-type tank group comprises a head tank, a middle tank and a tail tank, a plurality of overflow pipes communicating the head tank with the tail tank up and down are arranged on the K-type side of the K-type tank group, the overflow pipes correspond to the membrane filters one to one, a flow blocking filter is arranged in the head tank, and the middle tank is arranged in the middle tank. A combined filter vertically penetrating through the head tank and the tail tank is arranged in the middle tank and comprises a first-stage membrane filter and a second-stage membrane filter, the first-stage membrane filter comprises a top cover, a porous shell, a first filtering membrane and a Y-shaped pipe, the second-stage membrane filter comprises a porous inner core and a second