Riffle Tubes are used to enhance gravitation separation of high specific gravity solids. The riffle tubes operate to prevent the accumulation of such solids or deposits on the bottom of the bioreactor tank.
Rig moving tugs are ships approximately 60 to 70 feet in length, having 900 horsepower or greater, which are used to move barge rigs to and from the drilling location. They can also be used to move and position utility barges and moves materials and personnel to and from the barge rig.