Yesterday Wednesday evening , I was attended the Society of Petroleum Engineers Annual Lecture Series @ Rosana1 – Diplomatic Club Doha.
Qatar Society of Petroleum Engineers (SPE) kicked off its 2012 “Distinguished lecture series” with hosting Mike Gunningham, Maersk Oil Qatar’s Well, Reservoir & Facility Management Adviser.
Mike, who has close to 30 years of oil and gas industry experience, made a presentation on “Lunskoye Big Bore Gas Wells-Maximising Gas, Minimising Sand”.
Opening the session, Sheikh Faisal Al Thani, Deputy Managing Director of Maersk Oil Qatar and Chairman of the Qatar SPE, said: “The distinguished lecture programme provides a great opportunity for engineers to share best practice, knowledge and experience. There are some extremely talented professionals with a wide range of experience from different countries and companies working here in Qatar.”
The Lunskoye gas field development is a part of the Sakhalin Phase II project. The gas from Lunskoye will provide the majority of the Sakhalin LNG plant capacity with 1800 MMscf/d for plateau production. The 1st six wells, which will initially feed this LNG plant, are expected to produce 300 MMscf/d per well.
This presentation will look at how the sand face completion design has impacted the project. Developments with Shell’s Fully Integrated Sand Failure Prediction Tool enabled the sand volumes to be quantified and used for the first time during completion selection in Shell. The results predicted that unmanageable sand volumes would occur upon start-up, for open hole completions with pre-drilled liners (PDL).
This led to a revision of the sandface completion concept from PDL to cased and selectively perforated liner (C&P). A sand management strategy was developed, where the weakest zones are not perforated. Further studies from the exploration and appraisal wells indicated that, less than 10% of the net reservoir should be left un-perforated. The possibility of lower well productivities, resulting from C&P completion was assessed using inflow models. The resultant lower well deliverability has been more than compensated for, by deviating wells from near vertical to 55º through the reservoir and maximising the tubing size to a 9.5/8” monobore design. Well potentials are now over 500 MMscf/d, although they will be beaned back due to surface constraints.
With the selected completion minor amounts of produced sand are expected for C&P completions during the first 15-20 years of field-life, beyond which manageable amounts of transient sand are expected for remaining production lifetime. A sand management plan has been developed, to ensure the facilities and personnel are prepared and able to manage sand, in these high rate gas wells.
At the end of this presentation, I saw that cased and perforated completions are a sound form of sand control completion, optimizing production and minimizing risk.
(*** Dukhan Thursday Night, 05-01-2012 @ 11:55 pm)