pugmill mixers continuous mixers by Rapid

Rapid's pugmill mixers or pug mill is a machine in which materials are simultaneously mixed with a liquid. Industrial applications are found in cement and some parts of the concrete and asphalt mixing processes. Rapid's pugmill mixers is a fast continuous mixer. Rapid's continuous pugmill mixers can achieve a thoroughly mixed, homogeneous mixture in a few seconds. Mixing materials at optimum moisture content requires the forced mixing action of the pugmill mixers paddles, while soupy materials might be mixed in a drum mixer. Rapid uses a horizontal boxlike chamber with a top inlet and a bottom discharge at the other end, 2 shafts with opposing paddles, and a drive assembly. Some of the factors affecting mixing and residence time are the number and the size of the paddles, paddle swing arc, overlap of left and right swing arc, size of mixing chamber, length of pugmill mixers floor, and material being mixed.

Common construction and industrial uses include:

Road Base - Dense well-graded aggregate, uniformly mixed, wetted, and densely compacted for building the foundation under a pavement.

Lime Addition to asphalt - Lime may be added to the cold feed of an asphalt plant to strengthen the binding properties of the asphalt.

Flyash Conditioning - Wetting fly ash in a pugmill mixers to stabilize the ash so that it won't create dust. Some flyashes have cementitious properties when wetted and can be used to stabilize other materials.

Waste stabilization - various waste streams are remediated with pugmill mixerss forcing the mixing of the wastes with remediation agents.

Roller-compacted concrete - (RCC) or rolled concrete is a special blend of concrete that has the same ingredients as conventional concrete but in different ratios. It has cement, water, and aggregates, but RCC is much drier and essentially has no slump. RCC is placed in a manner similar to paving, often by dump trucks or conveyors, spread by bulldozers or special modified asphalt pavers. After placement it is compacted by vibratory rollers. The "stiff" nature of RCC may require a paddle type pugmill mixers to force the materials to mix completely and discharge easily.