US Patent 7476318 Drilling mud tank

A mud tank for processing drilling mud during drilling operations wherein the interior of the mud tank has sloping walls to guide sinking aggregate toward a sand trap disposed at the point of convergence thereof. The sand trap is comprised of the convergences area of the sloping walls and an inverted V-shaped cap member located thereabove along the entire length with ¼″ gaps provided between the edges of the cap and their respective sloping walls. Aggregate is drawn through the gaps into the sand trap by a sand pump that provides a suction line therein. A center-divider within the mud tank separates the tank into a dirty tank and a clean tank to provide redundant cleaning operation for more effective removal of aggregate.