The quality OSLO evaporation crystallizer, also known as Kristal crystallizer, is a mother liquor circulating continuous crystallizer. The operating feed liquid is added to the circulating pipe, mixed with the circulating mother liquor in the pipe, and pumped to the heating chamber. The heated solution evaporates and reaches supersaturation in the evaporation chamber, and enters the fluidized bed of crystals below the evaporation chamber through the central pipe (see fluidization).

In a crystal fluidized bed, supersaturated solutes in solution deposit on the surface of suspended particles, causing crystals to grow. The crystal fluidized bed performs hydraulic classification on the particles, the large particles are on the bottom, and the small particles are on the top, and the crystalline product with relatively uniform particle size is discharged from the bottom of the fluidized bed. The fine particles in the fluidized bed flow into the circulation pipe with the mother liquor, and the tiny crystals are dissolved away when reheated. If the heating chamber of the OSLO evaporation crystallizer is replaced by a cooling chamber and the evaporation chamber etc. are removed, a quality OSLO evaporation crystallizer is formed. The main disadvantage of this kind of equipment is that the solute is easy to deposit on the heat transfer surface, the operation is more troublesome, so it is not widely used.
The main feature of the quality OSLO evaporation crystallizer is that the supersaturation generation area and the crystal growth area are respectively set at two places in the crystallizer, and the crystals are fluidized and suspended in the circulating mother liquor, which provides a good condition for crystal growth.
The quality OSLO evaporation crystallizer belongs to the mother liquor circulation type continuous crystallizer. Enter the crystal fluidized bed below the evaporation chamber through the central pipe. In the crystal fluidized bed, supersaturated solutes in the solution deposit on the surface of suspended particles, causing the crystals to grow. The crystal fluidized bed performs hydraulic classification on the particles, the large particles are on the bottom, and the small particles are on the top, and the crystalline product with relatively uniform particle size is discharged from the bottom of the fluidized bed. The fine particles in the fluidized bed flow into the circulation pipe with the mother liquor, and the tiny crystals are dissolved away when reheated. If the heating chamber of the OSLO evaporation crystallizer is replaced by a cooling chamber and the evaporation chamber etc. are removed, a quality OSLO evaporation crystallizer is formed. The main disadvantage of this kind of equipment is that the solute is easy to deposit on the heat transfer surface, the operation is more troublesome, so it is not widely used.