Patent ID: 8568017

Claim:
A mixing device for mixing at least a first substance and a second substance, the mixing device comprising: a body having a first inlet in fluid communication with an open chamber such that the first substance flows through the first inlet into the open chamber; a mixing tube extending through the open chamber, the mixing tube having a first end to receive a flow of the second substance and a second end to discharge the flow of the second substance, the mixing tube having a plurality of injection openings formed in an outer wall of the mixing tube to allow the first substance to flow into a flow passage of the mixing tube through the outer wall to mix with the second substance, wherein the plurality of injection openings are located in a plurality of distinct and separate injection zones, wherein the injection zones each include a subset of the plurality of the injection openings and the injection zones are separated from each other by a portion of the mixing tube devoid of openings; and a regulating member surrounding at least a portion of the mixing tube, wherein the regulating member includes a plurality of regulating sections each movable along one of the plurality of injection zones, wherein the regulating member and the mixing tube are movable relative to each other such that each of the plurality of regulating sections move along one of the plurality of injection zones to simultaneously expose a varying number of the injection openings in each of the plurality of injection zones to the open chamber.