A fully compositional Integrated Asset Model (IAM) has been built for a giant gas-condensate field. The field is a complex retrograde gas-condensate reservoir with a hydrocarbon column up to 1750m in height. The fluid composition varies significantly with depth, ranging from a gas condensate to under-saturated oil. Production is centred on three processing facilities which are variously constrained by gas processing, gas compression & oil stabilisation capacities and overall export levels. There are some 100 producers and 15 gas injectors presently active in the field, with new wells and facilities planned as part of future development. IAM's for the total production system have been gaining in popularity for applications such as FEED studies, field development planning and optimisation. Their complexity has grown with the need to have fully compositional models, which are particularly important for gas condensate fields, where accurate fluid description is required for predicting condensate recovery and injection gas composition. Development of this IAM has required close cooperation between reservoir, production and process engineers since each of the component models - a 3D reservoir simulation model, production & injection surface network models and a process model for the three production units – are complex in their own right. The IAM model honours the well, network, and facilities constraints, taking into account interdependence between the different elements of the system. The IAM provides the capability to manage scheduled field events (well re-routing, plant maintenance, field uptime, etc) and optimizing field liquid production. This work offers valuable insights for more accurate assessments while evaluating different field exploitation strategies.

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This paper describes the novel experience of running Corrosion-Resistant Alloy (CRA) 25% chrome tubing with Dope-free connections in triple joint stands to reduce online running-in-hole (RIH) time. To achieve this, an international operator of a deepwater field development in Angola, defined a special set-up for the make-up and handling equipment, along with connections featuring Dope-free technology. 5 V2" production tubing strings were run in triple joint stands in 2 deep water wells offshore Angola. Well "A" had 14 triples while Well "B" had 67 triples installed. Running highly alloyed CRA tubing with Dope-free technology in stands, in conjunction with using the special handling equipment resulted in faster and safer installations, thus reducing operational risk and saving rig time for the operator. Furthermore, the thread compensator performed the make-up with the neutral point at thread pin thus minimizing stress at the thread's metal seal zone. Several other benefits recorded include savings in jet-wash water, zero dope discharge, reduced personnel exposure to risk, reusability of non-contaminated thread protectors and improved well productivity. The notion of installing highly alloyed CRA tubular in oil and gas wells initially considered too sensitive to be run in triples has been shown to be conservative. This paper shows that from field experience, running highly alloyed CRA tubulars with Dope-free connections in triples is achievable with demonstrable operational improvement and increased reliability.

Hydraulic fracturing technique is worldwide used to unlock reserves in tight formations. The Devonian layer, present in this field in the Berkine Basin (Algeria), is gas condensate bearing with a permeability range of 1 to 0.1 md; the zone shows also an highly tectonic stresses, and the frac gradient can rise easily values above 1.0 psi/ft. 3 previous fracturing treatments performed in 2005 and 2006 in 3 vertical wells were without success, due to the high stresses encountered, the wrong frac designs and completion limitation. Aim of this paper is describing the successful multiple propped hydraulic fracturing treatments, placed in a subhorizontal well in March 2012, listing all the actions done in terms of Completion design Materials choice and Frac schedule optimization. This paper describes also the multiple lessons learned experienced in the execution phase of the multifrac job about frac placement, frac design and completion choice, that have to be considered for the fracturing jobs already planned, in fact the good results of this treatment allowed the Operator to plan a future appraisal/development phase for the Devonian layer.