A weir box disposed upstream from conventional solids
control equipment of a mud
system of a drilling rig contains a drilling mud separation unit having a continuous-loop scalper screen that is driven in a continuous loop to separate, convey and
discharge large amounts of gumbo, heavy clays and
drill solids at the end of the separation unit. The
flow divider box is a box-like housing with a diverter plate, weir baffle plates and a sliding gate that allows
drilling fluid or drilling mud to be selectively directed to the mud separation unit to be separated prior to passing to the conventional downstream solids
control equipment or allows the fluid to bypass the separation unit and flow directly to the conventional solids
control equipment. The sliding gate is adjustable to selectively control or meter the flow rate and to create a
hydrostatic head upstream from the conventional solids control equipment. The weir box baffle plates, sliding gate, and selective utilization of the mud separation unit allows the operator to produce an increased
hydrostatic head, which enables high flow rates to be easily processed by
shale shakers and other conventional downstream solids control equipment of the mud
system and to compliment the drilling operation with respect to changes in the
lithology, geological formations, or loss of returns in relation to the gallons pumped or volume of
drilling fluid or drilling mud entering the weir box.