Curved blade mixing device

A method for continuously mixing and reacting liquid or solid feed materials with a solid granular heat-transfer medium in a mixing device, the method comprising:

• actuating a mixing device comprising at least two rotating shafts, at least two opposite rows of blades are disposed on each shaft, each of the row of blades having at least two individual blades, each of the individual blades being fastened to the shaft at a fastening point along a shaft diameter (DW) at an angle of incidence α to a longitudinal axis of the shaft, each of the individual blades being curved such that they exhibit an angle of incidence β to the longitudinal axis of the shaft at an outer diameter of the blades (DA) such that the angle of incidence β at the outer diameter of the blades (DA) is less than the angle of incidence α at the shaft diameter (DW), and that the angle of incidence α continuously decreases from the shaft diameter (DW) as the diameter increases and reaches the smaller angle of incidence β at the outer diameter of the blade (DA) such that the axial speed of the liquid or solid feed materials and solid granular heat-transfer medium at the shaft diameter (DW) is equal to the axial speed of the liquid or solid feed materials and solid granular heat-transfer medium at the outer diameter of the blades (DA), wherein the outer diameter of the blades (DA) is twice as large as the shaft diameter (DW) and the angle of incidence β is approximately half as large as the angle of incidence α.