Patent ID: 6964511

Claim:
A method for mixing a substance including liquid and solid constituents, the substance being contained in a tank having a floor, at least a portion of the solid constituents being settled on the floor of the tank, the method comprising: providing a mixing apparatus, the mixing apparatus including a frame, and a pair of opposing thrust generators pivotably mounted to the frame, the frame including an opening for receiving at least one of the thrust generators therein; lowering at least a portion of the mixing apparatus into the tank with the thrust generators in a first position wherein one of the pair of thrust generators is oriented generally within the opening and above the other of the pair of thrust generators; after said step of lowering, moving the pair of thrust generators to a second position spaced from the first position; with the thrust generators in the second position; mixing the liquid and solid constituents of the substance, including the settled solid constituents; moving the pair of thrust generators from the second position to the first position; and removing the mixing apparatus from the tank when the pair of thrust generators are substantially in the first position.