TEPNL Foam Assisted Lift Project

Transcription

1 TEPNL Foam Assisted Lift Project Maria Perez Fernandez Groningen, 26 th September 2012

2 Contents Overview Phases: Phase 1: Initial Contacts Phase 2: Gathering data Phase 3: Feedback Phase 4: Economic Analysis Phase 5: Field Trials Way Forward 2

3 Total E&P Nederland 84 wells 65 producing wells Current problems: Water breakthrough: plug settings. Salt deposition: water batches. Increase of skin: reperforations and clean-out. Lifting problems: velocity strings, reduction of WHP, foam injection. 19 wells with lifting issues. 3

4 Foam Project Overview Phase 2: Chemicals and well screening Phase 3: Foam screening and evaluation Phase 4: Economic analysis Phase 5: Design & execution of the surfactant injection Phase 1: Contact chemical vendors and operators 4

5 Timeline 5

6 Total Group Experience Total Workshop July 2012: Argentina Indonesia USA UK The Netherlands Conclusions: Important factors: Lower WHP. Depressurization of BHP. Concentration of: surfactant and condensates. Important parameters for well selection: Salinity GLR Water production 6

7 TEPNL Experience Bullheading Operation: Restart with ejector Bullheading Operation: Restart with low back pressure Operations: Initial positive result but the foam disturbed the liquid control in the separator and the platform was flooded with foam Conclusions: Probably too much surfactant used or not optimal concentration Good result Operations: Two restarts: with and without foam Conclusions: Efficiency of the defoamer Soaking time of 24 h is enough to bring the foam from top to bottom The well flowed 20% longer with foam Conclusions: Poor reaction of the well Perfs covered with clay 7

8 TEPNL Experience Bullheading Operation: Inject high pressure gas from nearby well Conclusion: little change in production Conclusion: good result after clean up Good result Capillary string Problems: Not effective foam, liquid could not be lifted The position of the capillary string, due to a restriction above the top perforations Recommendations: To have a downhole gauge with direct surface read-out which makes it easier to understand what is going on downhole and be able to react accordingly To increase the foam injection rate at the start Monitories the separator continuously during the foam test to detect foam carry over Lab tests before the capillary string Bull heading + foam lift + start-up via ejector Operations: Light the water column with foam Inject high pressure gas from nearby well Problems: The connection between the gas injected and the one present in the reservoir was not reached Bull heading period not long enough A lost of wellhead pressure prior to restart the well, due to a leaking choke Recommendation: Measurement of the liquid level at the first stage 8

9 Total candidate wells Priority Platform Well 1 K6 K6DN3 1 K6 K6DN1 1 K6 K6DN2 2 K5 K5D2 2 L4 L4A5 2 L4 L4PN3 2 L7 L7B1 2 L7 L7H3 2 L7 L7N2 2 L7 L7H2 3 K5 K5B1 3 K5 K5D1ST 3 K5 K5ENC4 3 L4 L4B1 3 L4 L4PN4 3 K4 K4BE2 3 K5 K5ENC3 3 K6 K6N1 3 L4 L4A3 3 K4 K4D1 3 K5 K5D3 3 K5 K5ENC1 TEPNL 19 candidates 3 Candidates for the initial batch 7 Priority wells 9 Candidates to be confirmed First trial Priority wells Candidate wells 9

10 Preliminary studies Gas and condensate production rates Pressure and temperature at surface and downhole conditions Lab test Downhole agitation Foam performance Compatibility: fluid, chemical, material and antifoam Emulsion tendency Physical properties: thermal stability, winterization and viscosity Costs Build-up time and half life of the foam Report: From free to 100 EUR/report Lab test: From free to 900 EUR/sample Field test: 3000 EUR/trial 10

11 Candidates Wells Chem 1 Chem 2 Chem 3 Chem 4 Chem 5 Chem 6 Well 1 Well 2 Well 3 Well 4 Well 5 Well 6 Well 7 Well 8 Well 9 Well 10 Well 11 Well 12 Well 13 Well 14 Well 15 Well 16 Well 17 Well 18 Well 19 Good application Moderate application 11

12 Field Trials Batch Treatment Essential for initial experience Get familiar with providers and products Prove the effectiveness of the products Water level measurement, needed to estimate the volume of water in place in the tubing Get information for next steps: capillary string Capillary String Uncertainties with the process and the economic profitability Already installed capillary for water management DHSV problem: Renaissance System Next year: installation of temporary and permanent capillary string 12

13 Way Forward Planning and scheduling: Lab test Field trials JIP on techniques for deliquification of gas wells Tool to rank FAL vs. other deliquification techniques Innovation Contract Upstream Gas project Selection of foamers for deliquification of gas wells Collaboration between operators 13