Innovative Jet Pump Design Proves Beneficial in Coalbed Methane De-Watering Applications

During the de-watering phase of typical Black Warrior Basin coalbed methane wells, an artificial lift method is needed to produce large volumes of water yet. have the ability to handle a moderate amount of produced solids such as coal fines and frac sand. In response to this scenario, the Coleman Pump Company developed a free style jet pump with a design specific to the problems encountered during coalbed dewatering operations. The unique design of flow passages in the pump allows retrieval of a very small portion of the pump while still providing a greater than normal flow capacity. In addition. the pump does not utilize any downhole moving parts which proves advantageous in a high solids environment to reduce workover expense. Meridian Oil applied the above technology to a test well in the Black Warr Coal Project. In this well, the pump was placed in the conventional or Basin threaded production tubing using a coiled tubing conveyed, concentric string, installation technique. This allowed the coiled tubing to be utilized as a power fluid path while water and gas were separated downhole and produced to surface independently through the dual annular spaces created by the concentric design. This design also provided for easy placement and retrieval of the throat and nozzle portion of the pump by using surface pump pressure. This design package provided a significant increase in water rate which resulted in an accelerated gas production rate and an overall increase in profitability for the well.