Gas Division Activities

Offshore Projects Department

is mainly to manage and  execute projects assigned from the evaluation stage and ensure optimization of economics of the project portfolio as well as each individual project until it is handed over to the Operations Department.

 

Main projects executed by the department and  future ones :

 

BAHER ESSALAM FIELD :

 

The field is located about 110 km from Tripoli coast. The field structure is an ENE,WSW trending narrow and elongated anticline about 50 km long and 4 km wide located in the central part of NC 41 area.

The reservoir rock is composed of Carbonate Facies; the petrophysical characteristics are generally good.

The exploration activities in the field started in 1977 and 1979 by drilling of two wells C1 and C2, followed by another five exploratory wells, the development plan calls for two phases,

 

 In 2003, the drilling activities in Bahr Essalam Phase 1 were to drill 15 Central wells and 11 west subsea wells 5 Midline and 6 Endline.  It was the first stage of Bahr Essalam gas field and a major challenge of Libya financially in different stages of the project until we saw the first results which clearly was a great success .

 

In 2016, the drilling activities in Bahr Essalam Phase II The project includes the delivery of the gas and condensate production from 3 new wells from the C Central A area and 10 new wells from the C East area to the existing Sabratha Platform. Gas and condensate production will be partially treated on the Sabratha platform topside facilities and then sent to shore through the existing gas and condensate pipelines to the Mellitah plant for final treatment to reach sale requirements.

 

Beside development the existing field, the owners’ strategy is also to develop other new structures in the same Area (NC-41) and put them in operation in the near future:

  • A Structure
  • E Structure
  • T&U Structures
  • D Structure
  • Other Minor Structures (G, H, K, P, M, F, & Q).

 

The production from the subsea and platform wells is treated on Sabratha Platform for separation and dehydration. The condensate is pumped through a 10’’ pipeline to Mellitah for further treatment and export.

The gas is transported through a 36’’ pipeline to Mellitah plant for final treatment and onward transmission to the local market to meet possible increase of local gas demand and export to Italy through the Green Stream compression station through 540 km 32’’ sea line and liquid hydrocarbons to export by vessels from Mellitah harbour.

 

 

ONSHORE PROJECTS

 

NC 118 DEVELOPMENT PROJECT

 

The field is situated about 250 km Southwest of Tripoli and about 300 km North East of the Wafa Field. The fast track schedule approach has a goal to have first oil by early 1st Quarter 2009.

The field development will be executed in 2 phases:

1- Natural depletion (early oil production) for the first 2 years
2- WAG (Water Alternating Gas injection) for the full field development after conducting pilot test to prove that the WAG method is technically successful and economically acceptable.

For the phase 1 the production will be through two oil production wells. At this time also 1 gas injection well will be drilled and completed, through which the associated gas will be stored in the reservoir, together with 1 water disposal well.
For the implementation of phase 2 (WAG) two additional injection wells will be drilled and completed, together with 3 water supply wells.
The Production Facilities for phase 1 will include flowlines & gathering system, two stage separation, oil desalting, stabilization, storage and pumping, gas dehydration and compression, waste water treatment and disposal, fire-fighting and ESD systems. A water injection system will be added for phase 2.
The development concept foresees the construction, installation and operation of a modular treatment plant on a rental basis (EPF, Early Production Facility) with the option to buy it after 2 years of operation.
Oil production will flow through a 55 km long 10” pipeline that from the field will connect with the Wafa-Mellitah pipelines North of Sinawen at Line Valve Station No. 8. The same pipeline will be utilized later for the gas export when the oil reservoir exploitation will come to an end and the gas exploitation will commence. All the required provisions for the tie-ins have been already made on the Wafa-Mellitah pipelines; therefore connection of the oil pipeline to the existing pipelines should be easy and straightforward.
The production profile foresees a maximum plant capacity of 10,000 BPD with a design life of 20 years.

WAFA DESERT

Wafa Compression Station

In the development plan of WLGP a decrease in the reservoir pressure was foreseen after 4 years of production. Updated reservoir study concluded that the need for compressors is expected to be after 5-6 years of production (i.e. by the end of 2009). Reservoir has completed and delivered the data (i.e. production profiles, pressure profiles etc.) needed to start the Engineering activities.

Electrical power supply for the temporary and army camps

In Wafa Field, Company retained the Contractor temporary camp and facilities. These facilities were fed by electrical diesel generators.
In order to avoid supporting additional costs for fuel and maintenance Operation dept requested to lay down an electrical cable from the Plant power generation. The scope of work has now to include both Temporary and Army camps.

Surface facilities for 3 new infilling wells

Three infilling wells (A34H, A38, A45H) and 1 Appraisal (A46) are envisaged to be drilled and completed starting from September 2007. Each well needs to be connected to the relevant Satellite area with flow-lines and all associated equipments (Electrical, Instrumentation, chemical injection package etc.).

Power supply for ESP installation in oil wells

Initially only the well A32 needed to be assisted by an electrical pump (ESP). Further analyses from Reservoir indicated the need of ESPs for up to 7 oil wells (A04H, A22H, A26H, A32H, A34H, A36H, A45H). This will require 2 power cables to be installed, one going from the Central Plant to the oil satellite 1 (N01) and another to the oil satellite 2 (N02). The 2 wells foreseen having ESPs installed in 2008 (A36H and A32H) are temporarily fed by diesel generators until the power cables are installed.

Production Enhancement

In order to asses the max potentiality of the Plant in line with the gas Pipeline transportation maximum capacity to achieve higher production rates, it was necessary to carry out a study to identify the potential bottleneck and optimize the Operation parameters.
The study was completed and final report received. According to the study the modifications required to increase 10% the design capacity (stage 1) are minor. Therefore it was recommended by Company Management to execute the implementation of the study stage 1 results.

MELLITAH COMPLEX

Smokeless flare

In order to reduce the environmental impact it is was decided to provide a smokeless flare (Steam blowing) in addition to the one already existing for the LPG facilities.

New accommodation

The number of accommodation provided in the original design became insufficient to accommodate the required number of personnel needed to run the Complex. Future expansion was already foreseen in the original development plan but no funds at that time were allocated. The current scope of work foresees additional 100 accommodations.

Nitrogen plant upgrading

During simultaneous purging of equipment in Mellitah Plant it happens that the demand of nitrogen is increased resulting in the operation delay and consequently production loss. An additional tank and related facilities are foreseen to mitigate the additional demand.

Waste water treatment plant upgrading

The existing waste water treatment plant cannot any longer cope with the increased personnel number at site. For this reason provisions have been identified to increase the numbers of treatment units.

Drilling

 

The mission of Drilling Completion & Work over Department is to carry out all technical and management aspects, related to the drilling, completion and well intervention. Find the easiest and most economical solutions to Reduce the HSE impact in according to NOC executive regulations .

 

Main Department Activities

 

  • Daily follow up the current operations in those wells which are connected with the drilling devices and tools
  • Prepare the Well Programs (Drilling, Completion  and Work over) technical, budgeting, time planning,  managing, materials etc.) in cooperation with the planning & Reservoir department.
  • Prepare the intent to drill and work over to NOC  in according to NOC executive regulations .
  • Budgeting, AFEs, Cost Monitoring, Accruals, Ticket & Invoices check and  Certification.
  • Execute the Well Intervention Operations slick line ,coil tubing and chemical treatment to increase the well productivity.
  • Record the electrical logs (pressure and temperature  &cement evaluation) for reservoir maintenance and  well life support .
  • Find the Eventually Problems Technical Problems Solving
  • Prepare the Technical Specifications for the Bids.
  • Prepare final drilling &work over wells operations reports.
  • Held the service quality meeting to evaluate the drilling contractors performance
  • Site visits to follow up the drilling and work over operations.

 

AREAS OF DRILLING OPERATIONS

 

OFFSHORE: Bahr Essalam Field (Contract Area D)

A total of 26 Gas& Condensate  wells were drilled and completed offshore (BE field ) Phase I.

  • 15 wells from Sabratha platform (central area)
  • 6 subsea wells (western area middle cluster)
  • 5 subsea wells (western area end cluster)

 

ONSHORE: Wafa Field (Contract Area D)

 

A total of 52 wells were drilled and completed onshore (Wafa field ) covering all the field area classified as following :

 

  • 15 Oil wells
  • 7 Oil/gas wells.
  • 29 Gas wells.
  • 1 Water disposal well .

In additional to 11 water supply wells .

 

 

 

ONGOING DRILLING , COMPLETION &WORKOVER  OPERATIONS:

 

 

 

 

OFFSHORE: Bahr Essalam Field (Contract Area D) II PHASE  PROJECT

 

A total of 10 Subsea wells were recently drilled offshore (BE field ) Phase II using the semisubmersible rig Ensco 5004 in 4 different locations. utilizing the latest  directional drilling technology .

In additional to3 Eni North Africa Exploration wells drilled with the same rig under MOG drilling team supervisions.

The operation is planned to be continued to perform the completions campaign on the 10 subsea wells .

 

 

 

BAHR ESSALAM FIELD ACTIVITY  Sabratha Platform (Contract Area D)

 

  • To perform the SGS campaign on Sabratha Platform
  • To perform next WH and x-mas trees maintenance on Sabratha Platform
  • To perform the FMWR maintenance

 

 

 

WAFA FIELD:

 

  • To perform the SGS & P.I   campaign ,coil tubing and chemical treatment

to increase the well productivity..

  • To Work Over 3 Well gas wells .
  • To perform well heads and x-mas trees maintenance
  • To prepare to drill new wells .

Production

 

Mellitah Oil & Gas is The operator of western Libya gas project (WLGP), which entails the development of two reservoirs; Wafa field located in the south west part of Libya, adjacent to the Libyan-Algerian border Approximately 500 km from the Mediterranean coast, Bahr Essalam field located offshore and covering an area distant between 30 and 350 km from the Libyan coast in water depth ranging from 70 to 350 m.
The main target of the project is to annually produce (10) BCM of sales gas; (8) BCM for export to GELA-Italy through Green Stream 32’’ pipeline and (5) BCM for the local market.

 

Wafa field

Oil and gas field with a significant gas cap and limited quantity of recoverable oil; it is producing gas and associated condensate from the gas cap through (30) gas wells and oil with associated gas from oil zone through (21) oil wells.
The production from (51) wells collected in different gathering stations (NG1, NG2, SG1, NO1 & NO2) and routed for separation and treatment at the central plant.
The on specification gas is delivered to Mellitah by the 32’’ pipeline (527 km), the average gas delivery is about 13 MMSm3 /day.
The production of oil & condensate sent to storage tanks in Wafa field , and then delivered in mixed mode with NGL coming from gas trains to Wafa Coastal plant by 16’’ pipeline for more processing. Approximately 23 KBbls of NGL and 38 KBbls of oil & condensate are delivered daily to Mellitah.

 

Bahr Essalam field

Gas field where gas and associated condensate are produced from (26) wells; (15) platform wells and (11) sub-sea wells.
The production is gathered on the platform where the gas is primarily dehydrated and approximately 28.2 MSCM/D (995 MMSCF/day) of sour gas delivered to Mellitah gas Treatment plants for further treatment by 36’’ sea-line (110 km), the un-stabilized condensate is delivered to Mellitah fractionation and stabilization units  for further processing  by the 10’’sea-line for stabilization.

 

Mellitah Complex

Comprise of Wafa coastal plant, Mellitah plants and Marine export facilities.

 

Wafa Coastal plant

Treats production received from Wafa desert and includes; fractionation and stabilization units to produce oil and LPG; the oil is routed to storage tanks with total capacity of about 2.5 MBbls, and the LPG is routed to the LPG splitter to produce commercial Propane and Butane which finally routed to fully refrigerated storage tanks, Propane storage capacity is about 230 KBbls, Butane storage capacity is about 210 KBbls

 

Mellitah plant

treats production received from Bahr Essalam field and includes; gas Treatment Units (GTU), sulfur recovery units (SRU), fractionation units and condensate stabilization units.

 

Gas plant

The raw gas received from the  Sabratha platform is treated in Mellitah gas  Treatment Units  to produce sales gas, the  Mellitah plant sales gas  combined with sales gas treated at wafa desert via Wafa coastal plant, then the  total  sales gas is delivered through fiscal metering to Mellitah gas compressor station ( MGCS ) for final export to Italy.
In addition the production of LPG (Propane, Butane) and stabilized condensate delivered to storage tanks with capacity of about 860 KBbls.

 

Sulfur RecoveryUunits (SRU)

Sulphur recovery units are designed to convert the H2S removed from the raw gas to elemental sulphur in a liquid form, which’s then sent to past illation unit for solidification and stored and exported  as solid sulphur.
Storage capacity of liquid sulphur is about 17,000 Sm3, and the storage capacity of the solid sulphur is about 25, 000 tons.

Marine export facilities

• Marine loading facilities contains two single mooring point (SPM) for the export of oil and condensate, one (SPM) is dedicated for the export of oil received from El-Feel field and wafa field
• the jetty is equipped for the export of LPG and Solid Sulphur.

 

Products & Production dates

 

Natural Sales Gas

On the first of September 2004 Started delivering gas from Wafa Field to Mellitah compressor station, the average sales gas was about 9.5 MMSm3/day.
Early September 2005 dehydrated gas arrived from Bahr Essalam Field to Mellitah gas plant for treatment and delivery to Green Stream, the average Sales gas from Mellitah gas plant was about 16.5 MMSm3/day.
On November 2005 start first delivery of gas to AR-Ruways power station near Nalut, approximately 5 MSm3 of Wafa sales gas delivered daily to the power station.

 

Crude oil and condensate C5+


On the first of July 2004 Started delivering Crude oil by 16’’ pipeline from Wafa Field, an average of 43 KBbls/day received in Mellitah as mixture of oil & condensate routed to storage facilities.
On the first of November 2005 starts receiving El-Feel crude oil from El-Feel field and mixed with Wafa crude oil in Mellitah complex, the Average oil received was about 140 KBbls/day.

 

Condensate C5+

In September 2005 the first offshore stabilized condensate from Mellitah gas plant was produced with an average daily rate of approximately 35 KBbls.

 

Liquefied Petroleum Gas -LPG (Propane (C3) & Butane (C4))

The first LPG Propane (C3) and Butane (C4) production from Mellitah coastal plant started in November 2004, the average Propane production is about 9 KBbls /day and the average Butane production is about 8 KBbls /day.
on the first of October 2005; the first offshore LPG production from Mellitah gas plant started, with an average production of about 1.6 KBbls /day of Propane and about 1.8 KBbls /day of Butane .

 

Solid Sulfur

the production of Solid Sulfur from pastillation units started on first of July 2006, the average daily production was approximately 350 tons.

Department: Geological & Geophysical

 

Purpose

Geological monitoring and management of Regional Geology and Reservoir

 

Main Responsibilities and Tasks

 

Geology and Geophysics

  • Collecting information in the field, from seismic and well data and other sources.
  • Monitoring the acquisition of data to ensure consistent quality.
  • Interpreting data to determine subsurface geology and the economic importance, using sophisticated technical software.
  • Developing geological models of the earth’s subsurface to understand the geological structure, rock characteristics and the likely distribution of oil/gas bearing strata.
  • Interpreting the results in consultation with other earth science professionals.
  • Assessing the potential quality of hydrocarbon resources.
  • Collaborating with drilling engineers to determine drilling locations on the basis of the interpretation of the data and models developed.
  • Producing and presenting geological maps and reports.
  • Performing detailed geological risk analysis of proposed exploration targets.
  • planning and undertaking well drilling programme, after collecting and modelling all available data.
  • Planning the location and trajectory of development wells and putting well proposals together in conjunction with the multidisciplinary team;
  • Creating new opportunities to access remaining reserves.
  • Implementing new technologies in geological modelling and seismic processing.
  • Advising engineers and senior management on geological factors affecting exploration.
  • Following Geological and Geophysical Regional/Reservoir Studies.

 

 

 

Department: Reservoir Engineering

 

Purpose

Reservoir monitoring and management

 

Main Responsibilities and Tasks

 

  1. Reservoir Monitoring and Surveillance
  • Monitoring of relevant production data & wells parameters to suggest any possible actions to improve the well productivity.
  • Performing cased hole logging (Production Logging and Reservoir Saturation Tools) in order to detect the inflow profile, current Fluid contacts and Fluid saturation profile.
  • Performing Static Gradient Surveys for Reservoir Pressure estimation.
  • Running Deliverability Test to evaluate the well production performance.
  • Carrying out Pressure Build up test in order to assist the well performance in terms of reservoir damage.
  • Designing & supervising stimulation and other rig-less work-over activities at well site as required.

 

  1. Reservoir studies & Economic
  • Estimation of initial hydrocarbon in place & reserves.
  • Updating in monthly bases the dynamic model in term of new collected information (production, pressure, completions change & etc).
  • Creating field production forecast for different development plans/scenarios as requested which including selection of new wells locations.
  • Performing cash flow and economic sensitivities analysis with profit indicators of any predicated scenario.
  1. Production Optimization & reservoir management.
  • Well Flow assurance study to optimize production and solve technical challenges.
  • Redesigning wells completion when necessary (adding new perforation intervals and/or perforations extension), and any kind of stimulation activities.
  • Create field development plans.
  • Preparing technical proposals /programs of the rigless and workover activities.
  • Carrying out production optimization study to get the best well candidates for artificial lift and other enhancement methods.
  • Preparing production allocation and well test reports per well on monthly base.
  • Comprehensive documenting of database includes well events and production of oil, gas and water in daily basis.

 

 

  1. Department Publication
  • Updating the official Reserve booklet of the company.
  • Annual status report.
  • NOC technical meeting presentation ( TCM).
  • Monthly production reports.
  • General assembly presentation.