Abstract: A system for extracting nutrients from raw manure comprises: a manure pump for transferring manure from a reception pit to a rotary cutter configured to cut fibers of the raw manure to a desired length to generate a manure slurry. The manure slurry is transferred to a preprocessing tank having an agitator for agitating the manure slurry. An infeed pump transfers the manure slurry from the preprocessing tank to a decanter centrifuge, the centrifuge having at least one solid outlet and at least one liquid outlet. A control system controls a flow of the raw manure from the manure pump to the rotary cutter, and from the rotary cutter to the preprocessing tank, the infeed pump and the decanter centrifuge, and also controls each of these elements of the system. A nutrient content of the resulting liquid centrate is reduced by at least 50% as compared to the raw manure.

Abstract: An engine repair stand of two holding frames, one for each side of the engine is provided such that the engine can be held a short distance above the ground in an upright or inverted position and moved by hand back and forth to readily reach all parts of the engine. The engine is held at its normal motor mount positions with the center of gravity of the engine off-set from the attachment position such that when the ends of the stand are rounded the engine may be turned over with ease by hand. Universal mounting members are provided so that the frame means generally constructed of tubular steel may be used with any type of engine.