Jim Hacksma Consulting Petroleum Engineering Automation Liquid Loading

Jim Hacksma, Consulting Petroleum Engineering Automation & Liquid Loading © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 1

Liquid Loading Solutions § Velocity Strings § Foam (Sticks & Liquid) § Plunger Lift § Beam Pumping § Wellhead Compression § Continuous Gas Circulation (CGC) ØA Relatively New Method § © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 2 Gas Lift 2

Velocity Strings § Easily Understood ØSmaller Tubing ►Higher Gas Velocity ►Liquids Removed ØA Seemingly Obvious Solution § But, Without Automation There Are Problems: ØFlow Is Limited To The Velocity String q. No Flow Thru The Annulus ØNo Single Tubing Size Suitable For Entire Well Life ØTubing Too Small – Too Much Friction ØTubing Too Large – Controls Loading Only A Short Time ØMust Change Tubing Often © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 3 3

Velocity Strings ¾” 1” 1¼” 2⅜” © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 4 § Lower Critical Rates § But, Without Automation… § Must Change Tubing Often § BECOMES VERY COSTLY 4

Velocity Strings (cont’d) Better With Automation: § One Tubing Size “Can” Be Suitable For Entire Life § Initially Install Smallest Tubing ►Lowest Critical Rate § Permit Flow Up Both Velocity String & Annulus ØLess Friction ►More Production § Add Gas Measurement To The Velocity String ØAutomatically Determine Critical Rate Of The Velocity String § Add Choke Control To The Annulus § When Total Well Gas > Critical Rate Of Velocity String ØPermit Excess Gas To Flow Up Annulus © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 5 5

Foam § Foam Deployment ØSticks Down Tubing ØBatch Liquid Down Tubing Or Annulus ØContinuous Liquid Down Capillary String Or Annulus § Problems Without Automation: ØFoam Performance Can Be Unpredictable ØEasy To Under-Treat ►Won’t Effectively Remove Liquid ØEasy To Over-Treat ►Higher Density And/or Friction ØIn Either Case, Casing Pressure Increases ØIn Either Case, Production Will Be Less Than Optimum © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 6 6

Foam (cont’d) Better With Automation: § Monitor & Minimize CP-TP ØBecause There Is No Established Critical Rate For Foam § Automatically Change Chemical Rate (More or Less) ØIf CP-TP Decreases, Continue In The Same Direction ØIf CP-TP Increases, Reverse Direction ØThis Must Be Done Very Slowly (Slow Response) © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 7 § CP Will Always Be Near The Minimum § Production Will Always Be Near The Maximum 7

Plunger Lift § One Of The More Effective Solutions For Loading § Also One Of The Most Complex Solutions § Most Advances Have Been Automation Related ØGreat Strides Have Been Made In PL Automation ØHowever, There Is Still Room For Significant Improvement ØImprovements Can Lead To Increased Production ØThe Plunger Itself Has Remained Relatively Unchanged § © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 8 With No Automation, There Is No Plunger Lift 8

Plunger Lift is Complex SI & Drop Build Press Open Well Push Plunger After Flow SI & Drop 9

Plunger Lift (cont’d) With Simple Logic § Must Make A Choice; Be Conservative Or Aggressive § With Very Conservative Settings ØPlunger Will Always Run ØBut, Production Will Not Be Optimum § With More Aggressive Settings ØProduction May Be Greater q Until Conditions Change & Plunger Fails To Run ØSimple Logic Is Unable To Quickly Adapt To Changes q. Changing Line Pressure Is The Most Common Problem q. Changing/Declining Well – Gas & Liquid Rates, Well Pressure, Etc. © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 10 10

Plunger Lift (cont’d) The Perfect Logic § No Human Intervention (Other Than Logic Design) ØController Automatically Changes All Settings ØFrom The Very First Cycle To The Very Last Cycle § Senses All Conditions During Pressure Build-up ØBased Upon Those Conditions, Automatically Determines The Lowest Possible (Earliest) Opening Pressure § Senses All Conditions During The After-Flow ØBased Upon Those Conditions, Automatically Determines The Optimum After-Flow © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 11 11

Plunger Lift (cont’d) The Perfect Logic (cont’d) § Adapts Perfectly To Changing LP & Changing Well ØUse Improved Opening Logic, Such As ►Foss & Gaul ►Rising Velocity ØUse Improved Closing Logic, Such As ►”Modified” Critical Rate ►Casing Pressure (or CP-TP) Changes § Use EFM In Optimization ØAutomatically Change Any Parameter (More Or Less) ØIf Next Cycle MCFD “Increases”, Continue In Same Direction ØIf Next Cycle MCFD “Decreases”, Reverse Direction © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 12 12

Plunger Lift (cont’d) The Perfect Logic (cont’d) § Without Human Intervention, The Controller Will (from the very first cycle to the very last cycle): ØAutomatically Change All Settings ØOptimize Production ØKeep Plunger Running (In Spite Of Changes) © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 13 § Don’t Have To Choose Conservative Or Aggressive § Pre-Determined (Fixed) Settings Are Not Optimum § Opening Pressures & Duration Of After-Flow May Vary From Cycle To Cycle 13

Beam Pump § On Oil Wells (Electricity Usually Available), Automation (Pump-Off Control) Is Very Effective ØElectric Motors Are Easily Controlled § But, On Gas Wells (Often No Electricity), Pump-Off Control Is Often Unavailable ØGas Engines Are Not As Easily Controlled § However, Need For Pump-Off Control Is Greater On Gas Wells Than On Oil Wells – WHY? § In Gas Wells Without Pump-Off Control ØAn Achilles Heel – GAS LOCK © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 14 14

Pump on Typical Gas Well § No Way To Control Pump Capacity (No Electricity): Ø 8 SPM ► 1¼” Pump ► 64” Stroke ►Capacity = 93 BPD ØWAY TOO MUCH PUMP FOR TYPICAL GAS WELL § Very Little Liquid Production In Typical Gas Well: Ø 100 MCFD ► 10 bbl/mmcf ►Only 1 BPD Ø 8 SPM ► 11, 500 Strokes/Day ►½ Oz Liquid/Stroke ØWAY TOO LITTLE LIQUID FOR BEAM PUMP § Gas Enters Pump, Because There Is No Liquid ØGas Separation Can’t Prevent It ►Pump Gas Locks ►FL Increases ►Gas Rate Falls ►Takes High FL To Unlock © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 15 15

Wellhead Compression WELL COMPRESSOR Suction Pressure (SP) Controller – Prevents Excessive SP & Excessive HP Demand. Throttles High Wellhead Pressure, Reducing The SP To Acceptable Levels. Recycle Controller – Prevents Very Low SP & Compressor Damage. When SP Falls Too Low, Valve Opens Permitting Gas From Discharge To Return To Suction. © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 16 THIS COMMONLY USED CONTROL SYSTEM WORKS VERY WELL 16

Continuous Gas Circulation (CGC) § New ►Uses Compressor To Circulate Thru Wellbore ØTwo Versions ►Two Different Compressor Locations § CGC-CO ØContinuous Gas Circulation – Circulate Only ØPurely A Circulating Device ►Does Not Reduce FTP ØNo Controls / No Automation § CGC-C&R ØContinuous Gas Circulation – Circulate & Reduce (the FTP) ØBOTH Circulates AND Reduces FTP ØUses Controls ►There Have Been Minor Control Problems © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 17 17

Continuous Gas Circulation (CGC) Separator CGC-CO Sales Meter Compressor Formation Gas = Sales Gas Circulated Gas Formation + Circulation = High Velocity Note Compressor Location: § Sales By-Pass Compressor § Does Not Reduce FTP Think Of CGC As Gas Lift, Except: § No Gas Lift Valves § No Packer § No Outside Source Of Gas © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 18 18

Where are the Controls? Separator CGC-CO Sales Meter Compressor § No Controls Are Needed § Then How Is The Correct Volume Established? § Compressor Cylinder Is In Effect The Controller § Line Pressure & Suction Pressure Are Known § Desired Compressor Rate Is Known ØEquals The Critical Rate § © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 19 Select Cylinder Size To Deliver Desired Rate 19

Continuous Gas Circulation Separator Compressor Choke § CGC-C&R Sales Back. Pressure Valve Now Conventional Compressor Location ØNow Need CONTROLS To Split Flow § Disadvantages: ØAdded Controls & Operating Complexity ØCompression Ratio & HP May Be Increased § The Big Advantage: ØINCREASED PRODUCTION ØCGC (to control loading) + Reduced FTP © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 20 20

Control of CGC-C&R § The Control Of CGC-C&R Is Very Similar To That For Conventional Wellhead Compression § As A Starting Point, Fig. “A” (below) Shows The Controls Commonly Used For Wellhead Compression Recycle Line WELL CGC-C&R FIG. A COMPRESSOR Wellhead Compression 21

Control of CGC-C&R § CGC-C&R Fig. “B” Shows 1 st Version Of Controls ØRe-routes Recycle Line Thru The Wellbore ØPrevents Low SP AND Increases Velocity In Tubing ØProblem ►Oscillation ►All Gas Sold OR All Circulated ØPreferred ►Part Sold AND Part Circulated, At All Times ØReason For Oscillation? ►Controller Is 30, 000’ Away From Compressor Suction (15, 000’ Wells) ►Very Compressible ►Slow To Correct Low SP ►Then System Over Reacts ►Result Is All Sales OR All Circulation WELL FIG. B Pressure Sensing Line COMPRESSOR 1 st Version Of Controls Back-Pressure Valve 22

Control of CGC-C&R § CGC-C&R Fig. “C” Shows 2 nd (Current) Version Of Controls ØReplaced Automatic Controller With Manual Choke ØInitially, Close Choke To Reduce FTP To Desired Levels q. Manually Adjust (Close) Choke Once/Day (? ) In Small Increments ØLater, As Well Declines, Open Choke To Maintain FTP q. Manually Adjust (Open) Choke Once/Week (? ) In Small Increments ØNo More Oscillation ►Always Some Gas Sold & Some Circulated ►But, Automatic Would Be Nicer Manual Choke WELL 2 nd Version Of Controls FIG. C COMPRESSOR Back-Pressure Valve 23

Gas Lift § When Applied To A Single Gas Well, Gas Lift Is Very Similar To CGC-CO. ØPerformance (Control Of Loading) Should Be Similar ØNeed For Controls Is Minimal (One Compressor & One Well) ØThe Only Differences Between CGC & GL Are: q. GL Usually Uses Downhole Valves, Packer & Gas Buy. Back Meter § When Applied To Multiple Wells…. ØI. E. ; One Compressor Serving Multiple Wells ØThen Automation & Controls Become Very Important © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 24 24

THANK YOU Jim Hacksma - Consultant © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 25

APPENDIX © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 26 § Slides Beyond This Point Will Not Be Presented During The Main Presentation. § They Will Be Referred To Only During The Question & Answer Period, If Needed. 26

Foam Curve FOAM NATURALLY FLOWING § § © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 27 As Much Art As Science Easy To Under-Treat Easy To Over-Treat OUTFLOW CURVE UNCERTAIN 27

Plunger Lift – Good Well OPENING PRESSURE § Long Flows § Short Shut-Ins § FBHP Nearly As Low As Flowing Well “SHORT” SI “LONG” FLOWS AT LOW FBHP TIME-AVG FBHP RELATIVELY LOW © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 28 28

Plunger Lift - Depleted OPENING PRESSURE “LONG” SI § Short Flows § Long Shut-Ins “SHORT” FLOWS AT LOW FBHP § FBHP Much Higher Than Flowing Well TIME-AVG FBHP HIGHER © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 29 29

Plunger Lift Curve § § § What Happens As Well Declines? ? Flows Shorten & Shut-Ins Lengthen Time-Average FBHP (Back-Pressure) Increases Production Decreases Fewer Trips Can Be Made – Eventually None BACK-PRESSURE INCREASES AS WELL GETS WEAKER © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 30 30

LOADING CRITICAL RATE Continuous Gas Circulation CGC-CO § § Maintains Low FBHP; Continuously Down To “ 0” Rate PERMANENT SOLUTION THIS CONDITION IS RECREATED CGC MAINTAINS LOW FBHP, DOWN TO “ 0” RATE, PREVENTS LOADING PERMANENTLY © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 31 31

Counter-Intuitive Separator Sales Meter Compressor Reasons Why People Think CGC Can’t Work: § Can’t Circulate ØOr, Can’t Circulate & Sell ►Or, Need Gas Lift Valves § Injecting Places Back-Pressure On Formation ØOr, Gas Will Enter The Formation ►Or, Need A Packer § Need An Outside Source Of Gas § Instead, CGC Is A Direct Solution To Problem ØIncreases Velocity ØShould Be An Obvious Solution § © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 32 FIRST, SI, CREATE DRY WELLBORE, UNLOAD 32

Re-creates Earlier Condition Same FTP Same Rate Same FBHP © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 33 Separator Compressor After Loading w/ CGC Before Loading Separator CGC Achieves Same FBHP That Existed Before Loading 33

Continuous Gas Circulation CRITICAL RATE § LOADING COMPRESSION § § CGC-C&R Use One Compressor To Both Reduce FTP & Circulate Conventional Compression Is Good, But Not For Loading Circulation Controls Loading 300# 100# PREVENTS LOADING PERMANENTLY CIRCULATION © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 34 34

Continuous Gas Circulation CGC-C&R § Best Of Both Methods, With A Single Compressor § Circulation Controls Loading Permanently § Reduced FTP Further Enhances Production § No Other Method Offers So Much § Problems Overcome: ØNo Erratic Gas Flow ►No Liquid Slugs ØNo Mismatch Between Compressor & Well Capacities ØReady Supply Of Gas To Compressor Suction ØNo Low Suction Kill ►Reduced Compressor Down Time ØNo Buy-Back Meter Needed As With Gas Lift © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 35 35

Gas Lift LOADING CRITICAL RATE § § § Performs Like CGC-CO, But Gas Lift Valves Req’d Packer Req’d Buy-Back Meter Req’d Workover Costs Incurred More Expensive Than CGC MAINTAINS LOW FBHP, DOWN TO “ 0” RATE, PREVENTS LOADING PERMANENTLY © ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 36 36

© ABB Group Totalflow Global Technical Conference 01 February 2022 | Slide 37