Liquid Pipeline Leak Detection - Ongoing Research to Evaluate Selected External Leak Detection Technologies Mark Stephens, C-FER Technologies Pipeline Safety Trust Conference, New Orleans LA October 20, 2016 www.cfertech.com 1 2016 Pipeline Safety Trust Conference
Rationale • Conventional Computational Pipeline Monitoring (CPM) methods have very limited ability to detect small leaks – Small leaks if undetected can lead to significant spill volumes • Interest in alternative External Leak Detection (ELD) methods – In conjunction with existing internal methods can provide system redundancy and thereby enhance overall leak detection capability – Have potential to address blind spot associated with detection of small leaks • Many ELD technologies are new and capabilities are evolving – Performance capabilities have yet to be verified – Difficult to verify through field trials and/or pilot projects • Actual pipeline leak events are rare • Realistic simulation of leak events problematic www.cfertech.com 2 2016 Pipeline Safety Trust Conference
External Leak Detection Methods • Continuous monitoring (in-ground systems) – Acoustic, temperature or displacement sensing (fibre optic cable) – Hydrocarbon sensing (electrical cable) C-FER Ground Based – Vapour sensing (permeable tube) Leak Detection JIP • Periodic inspection (airborne and/or satellite systems) – Visual inspection • Manual or automated image interpretation – Vapour sensing • Laser or ambient light absorption sensing • Flame ionization detection C-FER Airborne – Temperature sensing Leak Detection JIP • Thermal imaging – Displacement sensing • Laser light detection and ranging (LIDAR) www.cfertech.com 3 2016 Pipeline Safety Trust Conference
Ground Based Leak Detection Joint industry Project • Program objective – Experimentally valuate selected commercially available cable or tube based systems for leak detection on buried liquid pipelines • Technology focus DAS and DTS – Fibre optic cables for distributed acoustic sensing (DAS) and/or VST distributed temperature sensing (DTS) – Vapour sensing tubes (VST) – Hydrocarbon sensing cables (HSC) HSC • Deliverables – Independently verified data on system performance capabilities – Information to help vendors benchmark and improve their systems • Research partners – Enbridge Pipelines, TransCanada Pipelines, Kinder Morgan Canada www.cfertech.com 4 2016 Pipeline Safety Trust Conference
Experimental Design Considerations • Simulate leaks under real world operating conditions – Realistic soil conditions and sensor placement configurations – Realistic temperature differentials between oil and soil – Realistic release events • Representative driving pressures, hole sizes and flow rates • Range of release orientations (i.e. different clock positions) • Facilitate unbiased evaluation of ELD technologies – Matching conditions for competing technologies – Provisions to ensure ‘blind testing’ from vendor perspective • Ensure safe handling and disposal of hydrocarbons – Apparatus to accommodate full range of LVP hydrocarbon liquids – Near-term focus on diluted bitumen (dilbit) www.cfertech.com 5 2016 Pipeline Safety Trust Conference
Test Apparatus External Leak Detection Experimental Research (ELDER) Apparatus Retractable Enclosure Soil Containment Tank High Pressure Product Discharge Vessel Pump Skid with Acoustic Enclosure and Base Isolation System Catalytic Oxidizer Test Pipe with Release Ports Product Filter and Circulation Piping, Discharge Piping, Spill Containment Berm Vessel Pressurization Systems, Control Valves, Pressure Regulators and Product Storage Vessel Flow Meter Not Shown www.cfertech.com 6 2016 Pipeline Safety Trust Conference
Test Apparatus – Commissioning Trials www.cfertech.com 7 2016 Pipeline Safety Trust Conference
Soil and Sensor Placement Light compaction: backfill ← Trench boundary Candidate ELD sensor cable/tube Heavy compaction: placement locations undisturbed soil Soil placement considerations: Sensor placement considerations: • In lifts to maximize consistency • Sensing mechanism and vendor • Lift compaction varied to simulate recommendations undisturbed soil and consolidated • Pipeline construction and cable backfill installation feasibility • Insight from previous tests www.cfertech.com 8 2016 Pipeline Safety Trust Conference
Test Preparation www.cfertech.com 9 2016 Pipeline Safety Trust Conference
Apparatus Ready for Testing Testing involves the staging of multiple release events over a one-week period Release parameters and timing of release events not known by vendors www.cfertech.com 10 2016 Pipeline Safety Trust Conference
Ground Based Leak Detection JIP - Directional Findings • Leak detection capabilities varies between technology types and between vendors of a given technology type in terms of both detection threshold and time to detect • Detection capability can be significantly influence by sensor placement location and release orientation • Detection of small leaks (leak rates < 1% flow rate) is possible www.cfertech.com 11 2016 Pipeline Safety Trust Conference
Airborne Leak Detection Joint industry Project • Program objective – Evaluate selected technologies conveyed on airborne platforms for detecting hydrocarbon liquid leaks from buried pipelines • Technology focus hydrocarbon vapour sensing – Laser absorption hydrocarbon vapour sensing – Flame ionization ground temperature sensing – Thermal imaging • Deliverables – Models for volatile liquid vapour migration through soils, vapour dispersion in the atmosphere and thermal effects of leaks at ground surface – Evaluation of sensitivity of selected technologies for hydrocarbon liquid vapour detection in the atmosphere and temperature differential detection at ground surface • Research partners – Enbridge Pipelines, TransCanada Pipelines, Kinder Morgan Canada www.cfertech.com 12 2016 Pipeline Safety Trust Conference
Release Modeling – In Ground • Determine magnitude of “signal” reaching surface • Determine species of gases generated by liquid leaks Temperature change Vapour flux www.cfertech.com
Release Modeling – In Atmosphere • Determine hydrocarbon vapour plume concentration above ground surface 350 300 Height above ground Height Above Ground (m) 250 200 Class 1 150 Class 2 Class 3 100 50 0 1.0E-08 1.0E-06 1.0E-04 1.0E-02 1.0E+00 Concentration Pentane Concentraion (ppmV) www.cfertech.com
Model Verification Example • Confirm vapour flux model by collecting volatile compounds produced by liquid leaks in ELDER tests PI D www.cfertech.com
Technology Evaluation Example • Conduct controlled outdoor gas releases with vendor sensors mounted on boom-lift Central weather station Mobile boom-lift • Evaluate detection capabilities (up to 125 ft) Release points & weather stations C-FER Data Acquisition Trailer AITF mobile release lab www.cfertech.com
Airborne Leak Detection JIP - Current Status • Evaluation of technologies for detecting liquid leaks by sensing hydrocarbon vapours in the atmosphere is on going • Evaluation of technologies for detecting liquid leaks by sensing ground surface temperature changes is soon to start www.cfertech.com 17 2016 Pipeline Safety Trust Conference
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