RIASSUNTO
Description of Material:
This paper is a case history that shows the achievability and benefit of right-sizing production and injection facilities in a major oil field. The notion of right-sizing the field was prompted by the high operating cost. In addition, due to the mature nature of the miscible WAG flood, the Jay field facilities were producing at levels that no longer merit the elaborate separation processes and accompanying operating costs. The re-design of the Jay field facilities to right-size them with respect to current and future operating conditions is described in this paper.
Application:
Major oil and gas fields have elaborate processing facilities, which were designed for early field-life producing conditions. As a producing field matures, these elaborate facilities may need to be modified and streamlined to be cost effective in operating at significantly reduced oil and gas rates. These modifications are described as right-sizing of the facilities, because these changes can reduce operating cost, extend productive field life and increase reserves.
Results, Observations and Conclusions:
The Jay field commenced production in 1972. A water flood was initiated in 1974, and since 1981 the field has been undergoing a water/nitrogen miscible WAG flood. Over the first twenty years, the field produced at the plateau rate of 110,000 bopd using around 150 wells, of which 1/3 of the wells were used as WAG injectors. By 2009, the field rate had dropped below 4,000 bopd and high operating costs had significantly shortened reserve life. The field was down for one year, while the facility was re-designed to enhance runtime and stream-line process flow under current and future operating conditions. The right-sizing of the Jay facilities was completed in late 2009 and extended the field life and expected reserves by reducing lifting costs by over 35%.
Significance of Subject Matter:
This case history serves as an analog for other major fields with elaborate producing/injection facilities and high operating costs. Right-sizing of facilities will add reserves by lowering the field economic limit. Due to the success in right-sizing of the Jay field, further plant modifications are envisioned for Jay field in the future.