Foam Assisted Lift in the North Sea

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1 Foam Assisted Lift in the North Sea Identifying Unlikely Candidates Presented by Butch Gothard

2 FAL Program Loading occurs on all wells. The question that must be answered for each well is When will this loading cycle begin? Foam assisted lift (FAL) can be an integral part of the production plan to keep a well flowing at its true potential Three steps for a successful FAL program Well diagnostics Product selection Application assessment

3 Well Diagnostics

4 During the end of November / first of December of 2006, Multi-Chem performed an offshore Southern North Sea foamer study via batch application of liquid foaming agent. The platform utilized during the study was Perenco s 27 Echo a relatively low volume producing platform for both produced gas as well as produced water volumes. The production from the test platform was transferred via commingled production to the main production platform 27 Alpha and as a result, no test separation was taking place on the test platform. Additionally, there was no individual well test (production) data available. As a result, treatment designs were based around Echometer fluid level data taken prior to each treatment, and prior to post treatment flowback. Pretreatment dummy shut in / flowback testing was also performed on each test well to determine what percentage of the post treatment incremental gas flow increase could be attributed to the pressure build up only, and what percentage could be attributed to foam induced liquid unloading of each well. The foamer study was performed on five wells via dual batch treatment applications, with each application varying based upon wellbore and/or expected formation fluid volumes, with shut in intervals varying from 16 to 48 hours.

5 Of the five candidate wells selected for the test period, the pre-treatment gas flow rates ranged from 0 mmscf/d to 1.0 mmscf/d. The well producing 1.0 mmscf/d was not expected to be producing under liquid loaded conditions based upon flow history of the well, which was confirmed via Echometer fluid level readings and dual foaming agent batch applications. Of the remaining four wells, gas flow incremental increases were recorded ranging from 100% to 500% over a 0.5 to plus seven day period, with a total of 9.5 mmscf/d over the seven day observation period. Testing was suspended after the seven day period due to additional ongoing platform projects and time constraints. Preliminary test results indicate that liquid unloading of some of the test wells would be best achieved via continuous capillary string injection of a liquid foaming agent, while cyclic batch application of liquid foaming agent may be the desired application for other test wells.

6 Echometer Well Analyzer Package

7 Echometer Software Package

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12 Summary FAL is an important tool When performed properly can be the difference between success versus failure Onsite evaluation of produced fluids and products is essential The use of Echometer analysis can be a very useful tool when production data is not available Batch application for foam trials is a very inexpensive tool