A Successful HSE Management Process Implementation During Drilling andWell Testing Operation in Sour Gas Wells

摘要

ADNOC took up the challenge to drill,test and produce the highly sour HPHT gas reservoirs with +30%H2S and 10 % CO2 in brown field.The objective of the appraisal program was to gain valuable reservoirdata by drilling and then testing the highly sour wells in order to finalize the facilities design and full fielddevelopment plans.Before drilling the wells in the high sour environment,an extensive safety review of the area,emergencyH2S zones,rigs technical capabilities,equipment required for safe operation,testing equipment design andits layout,crew competencies and SIMPOS protocol was prepared.The HSE requirements checklists weredeveloped,reviewed and agreed based on the scope of work both for the drilling and testing phases in ahighly congested brown field.The aim was to complete entire operation expanding over 2-3 years withoutjeopardizing the nearby activities and production.Due to the critically and strategically importance of the project,all the available best practices andtechnical competencies were applied in this project which allowed to overcome all the SAFETY challengesduring drilling,tie-in and testing of these crucial wells.All objectives were successfully achieved with noHSE incidents and failures.Findings and lessons learned are being used to tailor next stage of the projectto ensure most efficient scenario of Field development to support country's increasing gas demand.All existing HSE assurance measures,procedures and programs were reviewed and implemented to suitthe condition of sour wells including:1.Fire & Gas detection,Emergency Shutdown Systems and their layouts;2.Environmental Impact Studies focusing on the potential effects of flaring from sour wells includingZero spill and safe disposal of produced fluids into dedicated disposal wells drilled;3.Establishing and aligning all communications for imposition of EPZ(emergency planning Zone)and Site Specific Safety Plan with emergency response/evacuation procedures including SIMPOSwith multiple evacuation route maps prepared.4.Emergency communication protocol was developed considering the nearby population/towns incase of any gas release.5.Civil defense,Police and other governmental agencies were informed and ensured theirparticipation during the large scale exercises carried out This paper provides an insight of steps taken to achieve the target of drilling/testing highly sour gas wellssafely in brown field.Successful implementation and close follow up of all measures/controls identifiedin SIMOPS thru multiple audits;resulted in drilling,tie-in and testing of Sour gas wells with no safetyincidents or injuries.All routine rig and rigless activities in the vicinity were performed safely complying fully with SIMOPSand no operation was stopped.This paper emphasis importance of following all rules and regulation set by HSE to achieve the objectivesafety and efficiently.