Apparatus for moistening mixable materials

Claim 1

Apparatus for moistening a mixable material by the multistage addition of a moistening liquid, comprising a container rotatable about a substantially vertical axis and arranged to hold the material to be mixed and moistened, a vertically arranged relatively low-speed rotatable main mixing tool located within said container for mixing the material, a vertically arranged high-speed low-inertia auxiliary mixing tool located within said container and spaced laterally from said mixing tool so that its path of rotation is outside the path of rotation of said main mixing tool, driving means for rotating said auxiliary tool in the material, means for a step-wise addition of moistening liquid to the material to bring its moisture content to a predetermined level, control means for regulating said means for a step-wise addition of moistening liquid to the material determined in dependence on the power consumption of said driving means for said auxiliary mixing tool, and said control means includes a means for affording an interval in which the moistening liquid thoroughly mixes with the material before the power consumption of said driving means is determined, wherein the improvement comprises a hopper for supplying measured quantities of material into said container, temperature sensing means positioned within said hopper for determining the temperature of the material to be supplied into said container, and said control means includes a control device connected to said temperature sensing means for regulating the admission of cooling water to said container and regulating the cooling period after the admission of the water based upon the temperature determined by said temperature sensing means for establishing a predetermined starting temperature for the material within said container prior to the multi-stage addition of the moistening liquid.