Enhanced oil recovery methods (EOR) methods such as Steam Assisted Gravity Drainage (SAGD), Cyclic Steam Stimulation (CSS), steam drive, solvent and electric heating allow production of highly viscous crude oil at elevated operating temperatures (>160°C). The choice of artificial lift technique is critical to overall well performance. Therefore it has been a challenge to find a reliable artificial lift pumping system for heavy oil thermal recovery. Available options such as beam pumps and electrical submersible pumps (ESP), which are well proven in the petroleum industry, are not particularly well suited for thermal production. Progressing Cavity Pumps (PCP), with elastomeric stator, are economic to run and have performed well in heavy oil cold production. Since their elastomers are limited in temperature (<160°C), a metal PCP technology has been developed through numerous research works to meet the high temperature requirement of SAGD and other thermal recovery processes. This paper describes the successful application of KUDU PCM Vulcain TM metal PCP systems for SAGD process in Athabasca reservoir, beginning from 2007. We made analysis on production optimization in SAGD well pairs equipped with the PCM Vulcain™, which consists of a hydroformed metal stator and matching rotor utilizing special metallurgy to resist wear and maximize run life. In particular, the production with metal PCP in these wells reached the value of 200 m3/d at pump intake temperature of 200°C, performing volumetric efficiency of 82%. In general, the field results have demonstrated that the strong resistance of metal PCPs to chemical and mechanical degradation makes them a good alternative for the cold production of heavy and extra heavy oil with relatively high bottomhole temperatures and high aromatic, CO2 or H2S concentrations. This paper can be a guide for special heavy oil hot production PCP technologies to be spread and applied for EOR projects widely in the world.

No abstract

The ZH field located in Kazakhstan is comprised of shallow, unconsolidated sandstone reservoir that is being produced medium sandy oil by the help of progressive cavity pumps (PCP). The nature of unconsolidated reservoir makes overall production inefficient; due to sand production being a major concern in the field. High frequency of workover operations and limited productivity of wells were caused by sand production. Moreover, pump seizure happens more often because of the low fluid velocity, there is sand inside the production wells can not move up to the surface.The goal of this study is to increase oil production by optimizing the progressive cavity pumps operation. Improving production requires minimizing workover frequency, therefore sand should be lifted out of the well continuously with the fluid. This can be achieved by controlling the ratio of the actual fluid velocity to the sand settling velocity. The fluid velocity in the tubing should be enough to lift most of the produced sand particles from the bottomhole of a well.The statistics showed that production wells with fluid velocities of 75% of sand settling velocity or less were likely to have pump seizure with the lack of sand carrying capacity in the tubing. By increasing pump size, modifying tubing size, and increasing pump rotation per minute (RPM), PCP performance was significantly improved. This paper shows the significance of the parameters stated above.Field cases in PCP optimization are summarized. The successful cases highlight an incremental oil production of 126 m 3 /d with seldom workover. Unsuccessful cases were characterized by often and sudden pump seizures with increased watercut. This study has shown that maintaining production rate through PCP operation coupled with continuous sand lifting is more beneficial than controlling the sand production such as installing gravel packs.

No abstract