The thirst for energy continues to push companies to exploit oil and gas reserves in more challenging areas of the world.
The El Merk fields being developed by the Sonatrach/Anadarko (Contracting Authority) and partners in the Algerian Sahara desert are a good example.
The El Merk fields are located 300 km southeast of Hassi Messaoud, a remote, harsh desert location in the Berkine Basin where the terrain is mainly large interlocking sand dunes. The remote location and challenging environmental conditions pose challenges for ABB, charged with providing the offsite facilities for the project. Over the course of the project, ABB will supply some 900 km of trunkline and flowlines and install about 600 km of them.
The oil and gas fields being developed are located in Block 208 which contains four fields – EKT, EMN, EME and EMK and Block 405a which contains the MLSE field and is being developed as unitized production with the EMK field. Within each field in Block 208, production will be from three different reservoirs, namely the TAGI oil reservoir and the RKF and Strunian gas-condensate reservoirs. Block 208 is located 90 km south of the Sonatrach/Anadarko-operated Hassi Berkine South (HBNS) oil field.
The El Merk central processing facility will be the hub for processing oil, condensate, and associated gas from the four fields within Block 208 and adjacent blocks 405a and 403a/404.
Natural gas liquids will be transported from Hassi Berkine facilities (B404/403a) for fractionation. The development plan for exploiting the reserves is to produce stabilized oil, stabilized condensate, and LPG for export.
The nominal capacities of the project are: two 65,000-bpd (each) oil/condensate processing trains; a single 600 MMscf/d NGL recovery train; water-injection facilities for 155,000 bpd; and gas-injection facilities for 500 MMscf/d.
The nominal peak export rates (including the NGL production from blocks 404/403a) are: 90,000 bpd of oil, 36,000 bpd of condensate and 35,000 bpd of LPG.
The accompanying map indicates the geographical location of the development and illustrates its position with respect to the adjacent blocks.
The table below summarizes the breakdown of contracts involved in the development.
*ABB’s contract covers Lots 3 and 4 that are combined and designated as the Offsite Facilities Package.
The Offsite Facilities contract packages awarded to ABB cover the design, procurement and installation, construction, commissioning and start-up of the field gathering stations, gas distribution manifolds, well sites and 900 km of flowline and trunkline installations.
The field gathering stations being provided will include valved manifolds to combine flow from individual wells for production gathering and well testing using multi-phase flow meters. The manifolds will also distribute lift gas and dilution water to the TAGI oil-producing wells. In addition, at certain field gathering stations, water injection/dilution water pumping and filtration facilities will be provided. All field gathering stations will be supplied with 30 kV of power. Distribution system and chemical injection facilities will be installed at each respective station for both production and water-injection systems.
ABB is also providing the unmanned gas distribution manifolds for the distribution of high-pressure gas from the gas injection trunklines to individual gas injection well sites and for the supply of lift gas to the field gathering stations. The manifolds will be designed with manual operation only, with no power or telecommunications.
The contract also requires gas injection and treated produced water transfer and injection trunklines that respectively connect the central processing facility to the gas distribution manifolds and the central processing facility to the field gathering stations and/or disposal-injection well. All production trunklines will be provided with pig traps.
The work that forms ABB’s Lot 4 contract includes the oil production, gas-condensate production, water source, water injection and gas injection well site facilities in the EMK, EKT, EME and EMN fields. The scope of supply is relevant to 120 wells and also covered is the hook-up of 80 of the 137 total wells and flowlines for the full field development from contract award until six months after early oil.
ABB is also responsible for the flowlines to connect the production well sites to field gathering stations and/or directly to the central processing facility and to connect gas distribution manifolds to the gas injection well sites and to connect field gathering stations to the water-injection well sites. In addition, gas lift flowlines will be installed between the gas distribution manifolds, the field gathering stations and the TAGI production well sites and dilution water flowlines will be installed between the field gathering stations and the TAGI production wells.
All well sites will be supplied with electrical power from the field gathering station’s via buried cable and a separate fiber-optic cable will be installed for data and telecommunications. At all production and water source well sites, chemical-injection facilities will be installed. In addition, nitrogen degassing and pumping facilities will be provided at the water source well sites.
ABB’s contract, valued at $490 million, was awarded by Grouperment Berkine, an Algerian entity that is co-managed by Sonatrach and Anadarko. Significant production from the development is scheduled to begin in 2012.
Although not yet awarded, the El Merk project calls for construction of new export and infield pipelines. The export pipelines at El Merk will include:
- A 20-inch diameter oil pipeline and associated facilities at the end of the pipeline to enable tie-in to existing storage tanks and OH3/OH4 pipelines at the Hassi Berkine central storage facility;
- A 16-inch diameter LPG export pipeline and associated facilities at the end of the pipeline to enable tie-in to the existing LR1 LPG pipeline system at Gassi Touill; and
- An 18-inch diameter condensate export pipeline and associated facilities at the end of the pipeline to enable tie-in to the existing NH2 pipeline at Gassi Touill.
All export pipelines will be provided with pig launching and receiving facilities at the pipeline end stations. Valve stations for intermediate pipeline isolation will be installed along the export pipelines at intervals no greater than 40 km apart. Pipeline intermediate isolation valves will be provided with remote closure capability. Pipeline end stations and intermediate valve stations will be securely fenced and locked.
Plans also call for fiber-optic cable to be installed along the export pipeline routes to provide voice communication and transmission of valve position, pressure, and temperature to the central processing facility CCR via SCADA at each valve station. The cables will also provide telecommunications links to Sonatrach’s pipeline company, the Groupement Berkine office in Hassi Messaoud and the Hassi Berkine south-central processing facility.
The project will also require 12-inch diameter NGL transfer pipeline to enable NGLs to be exported from the existing Hassi Berkine central processing facility to the El Merk central processing facility. The same requirements with respect to pig traps, valve stations and fibre optic cable as that described for the export pipelines shall apply.