US Patent 7559362 Downhole flow reversal apparatus

A water reinjection arrangement for a coal bed methane well to minimize water disposal problems at the well surface. Water is withdrawn by a motor driven pump from an upper coal seam through openings in the upper portion of the well casing. A flow reversing head is provided within the well casing and into which the withdrawn water is directed. The water flow direction is reversed by about 180° and is conveyed within the well casing through tubular conduits to a downstream flow collector and into a downflow pipe, to be injected into a lower seam through openings in a lower portion of the well casing wall. A sealing arrangement is provided within the well casing to seal off the upper coal seam from the lower seam.