Operators of shallow, low flow oil and gas wells have commonly relied on conventional beam pump and other artificial lift methods to produce these types of wells. Often, the use of these pumping systems results in inefficiencies, short run-life and environmental challenges that affect the overall economics of the operation.
A hybrid artificial lift system has been developed to allow operators of shallow, low flow oil and gas wells the opportunity to produce the wells in a much more economical fashion than beam lift or other conventional methods. This paper introduces the technical aspects of the system, its operation and deployment techniques, and the power savings it realizes in comparison to beam lift and other traditional lift systems.
The Hydraulic Diaphragm Electric Submersible Pump (HDESP) uses a technology that offers a number of benefits to operators. The system's hybrid design advantageously combines the beneficial features of both electric submersible pumps (ESP) and hydraulic diaphragm pumps (HDP). Both of these types of systems are widely accepted in their respective industries.
Laboratory tests and deployment of the HDESP in producing wells confirm the systems capabilities in vertical wells up to 2500 feet in depth with production rates less than 200 BFPD. Ongoing design engineering has objectives of greater depths and higher volumes. Heat issues commonly associated with electric submersible motors are also being addressed.
Abrasives and gas handling comparisons are made between ESPs and beam pumps. Procedures optimizing HDESP reliability within adverse wellbores are also described.
Power cost studies indicate that the HDESP can reduce electrical cost by as much as 50% compared to beam pumps and water-well type ESPs. The net positive suction head (NPSH) requirement is considerably less, allowing an operator to drawdown fluid levels very close to the pump intake. This offers potentially significant production benefits to the producer.
At the conclusion of the paper, readers will have a thorough understanding of the function of the HDESP system, its performance successes and failures, suitable target applications, deployment techniques, and the overall potential for economic benefit the system brings.
The HDESP is a positive displacement pump that comprises two main components:
an oil filled submersible electric motor and,
twin acting diaphragm tubes.
The entire system contains hydraulic oil and is sealed against intrusion by well fluids. The stainless steel construction makes it resistant to corrosion. Figure 1 illustrates the internal components.