Production optimization dhbk

Introduction:Production Optimization Truc Doan •1 Outline • Introduction • Well Performance • Estimated Ultimate Recovery / Reserves • Well Operations • • • • Remote Booster Compressor (BC) Blowdown Well Cycling Well Unloading Unit (WUU) • Well Interventions • • • • Water shut-off Foam Injection  lifting liquid Re-perforation  reduce skin Acid stimulation/ acid wash  reduce skin • Mechanical Problem Introduction Production Optimization = Max rate? What’s PE concerned? • Gas Buyer’s nomination? • Sale target in each funnel? • Gas rate in each platform/ funnel? • Reserves of each platform/well? • any behind pipe? • Incremental Rate Potential? • Risk? • ELU & Slick-Line Unit Scheduling? • Maximize BC rate? • CO2/BTU? • Condensate/ water rate? Sale Target MDQ = xxx MMscfd • Water Injection Capacity • High back Pressure •3 Introduction Production Optimization = Max reserves? What’s PE concerned? • Reservoir Management • Maximize recovery factor • Reservoir Correlation i.e best producer(s) • Reserves of each platform/well? • Risk? • No flow or under performance? • Time for BC for higher recovery? • Most of the time  delay • Single/Commingle sands to maximize the EUR? •4 Introduction How to Balance Rate vs Reserves Max rate Max reserves • Meet sale target in short term • Maximize reserves, less investment • Less time to W/L move units • Delay of behind pipe reserves to production • Risk of water  loss of reserves • More wells/platforms to operate/maintenance • More drilling projects, more investment • More W/L unit move (less efficiency) Introduction Typical Gas Well Life Cycle in GOT Drilling & Completion Well Intervention Well Production/ Operation Time Line iTTP Natural Decline Post-Prod TTP Operational Operationalchallenges challenges Re-TTP High Drawdown WSO High Water Cleanout Fill/ Scale Put into BC Cycling Blowdown Depleted Plug and Abandonment Well Performance Inflow performance BHP • Initial reservoir pressure Pi Pres • Gas being produced, reservoir pressure and gas rate decline VLP • Reservoir is depleted Gas rate Well Performance Vertical flow performance (no aquifer) Ppipeline FTP Pressure • Well produce at constant gas rate • FTP limit at pipeline pressure, gas rate declines • Hook the well to BC, gas rate increase • Produce at constant suction pressure, gas rate declines BHP Depth Pi Well Performance Vertical flow performance (with aquifer) Ppipeline FTP FTP Pressure • Well produce at constant gas rate • FTP limit at pipeline pressure, gas rate declines • Gas & water mixture is producing • Hook the well to BC • Water start loading • Water load up BHP Water breakthrough the well Depth BHP Pi Well Performance Well Test/Well Chart Log scale Cum condy Condy rate Water rate Chk size Gas rate WGR Cum gas THP Example: Well X Natural Flow BC Well Operations Blowdown • A procedure which intentionally produce the well to flare system (0 psi) for a short period of time in order to provide maximum drawdown lifting liquid in wellbore and kick-off production Gas to Flare Boom psi Well Test Separator Flare Boom Liquid to Sump Tank Sump Tank Pipeline (or launcher) Example: Well Y B/D B/D Well Operations Well Cycling • A state where a well can be produced periodically by Shut-in and Re-open, then Shut-in and Re-open again and again in a proper duration 1500 200 1000psi psi psi 200 psi 1500 psi Open up Well Well Shut in Example: Well Z S/I periods Open periods Well Interventions Water shut-off Pres DP Depth Pressure Well Interventions Water shut-off • Mechanical seal • Tubing patch • Tubing plug • Cement squeeze • Seal off porous media of target sand • Polymer/Chemical squeeze • Change rock permeability Well Interventions Water shut-off -> Cement Squeezing • Shut off produced water • Repair casing leaks • Abandon depletes zone • Selective shut off for water injection • Seal lost circulation • Stop fluid migration •Fluid Migration Water shut-off Example Before WSO After WSO Well Interventions Foam Injection  lifting liquid Before inject After inject  Reduces the critical velocity of the well  Enables liquid unloading Well Interventions Re-perforation BHP Gas rate Re-perforation Example Before re-TTP After re-TTP Well Interventions Acid Stimulation BHP Formation damage Gas rate Mechanical Problem Wells Mechanical Problem Wells: Prioritized List • TRSV Failure to gain significant reserves back to production as soon as possible • Fish • High Hang Up Depth (HUD) •Tubing Issues Effective SLU Plan TRSV TRSV TRSV Failure 'X' Nipple 'X' Nipple 'X' Nipple P1DP P1DP (0') AZI HUD (Hang Up Depth) P1DP P1DN (0') Fishing P1DP P1DP (0') Well Interventions Acid Wash Scale Sand production