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www.tge-gas.com Page 1Rev1_2020
TGE GAS ENGINEERING
LIQUEFIED GAS TERMINALS
DESIGNED WITH SAFETY AT HEART
www.tge-gas.com Page 2Rev1_2020
▪ The cycle of process safety design
▪ Typical safety systems in a cryogenic gas terminal
▪ Marine installations & Transfer System
▪ Storage Tank
▪ Sendout Systems
▪ Fire Protection
▪ Conclusions
OUTLINE
www.tge-gas.com Page 3Rev1_2020
THE LIFE CYCLE OF PROCESS SAFETY DESIGN
HAZARDS
Identify• HAZID
• HAZOP
Analyse / Understand• Consequence Modelling
• Fire Hazards Assessment
• Quantitative Risk
Assessment (QRA) Control• Process Control
• Alarms
• Safety Instrumented Functions
→ SIL Assessment
Mitigate• Fire, Gas & Spill Detection System
• Control of Ignition Sources-
Hazardous Area Classification
• Spill Collection
• Fire Fighting System
• Passive fire and cold embrittlement
Protection
www.tge-gas.com Page 4Rev1_2020
A TYPICAL IMPORT TERMINAL
Reganosa LNG Terminal. Spain
www.tge-gas.com Page 5Rev1_2020
MARINE INSTALLATIONS
• Hazards
• Ship collision
• Releases on water → large flammable
clouds, pool fire, RPT
• Shared jetties, handling different products
• International crews → Human Factors
• Control / Mitigation
• Port traffic control
• Ship-to-shore link
• Powered Emergency Release
Couplings (PERC)
• Emergency Shutdown system (ESD)
• Impounding basinReganosa LNG Terminal. Spain
www.tge-gas.com Page 6Rev1_2020
TRANSFER SYSTEM
• Long pipeline (can be a few km)
• Usually kept liquid full with recirculation
• Allows quick start-up
• Avoids formation of vapour pockets
• Risk of hydraulic pressure surge (e.g. in
case of emergency shutdown (ESD)
• Transient surge analysis to ensure inherently
safe pipeline and supports design.
• Risk of trapped cryogenic liquid
• Thermal Safety Valves (TSV)
• TSV discharge to the tank to avoid flaring
Vystok LNG Terminal. Russia
www.tge-gas.com Page 7Rev1_2020
STORAGE TANK
• Very large inventory of liquefied gas
• Several tank designs:
• Single containment
• Double containment
• Full containment
• Steel outer wall
• Concrete outer wall
• In-tank pumps
• Often large, multi-level tank-top platforms
Grangemouth Ethane Tank, UK.
www.tge-gas.com Page 8Rev1_2020
STORAGE TANK HAZARDS
SINES LNG Terminal
• Overpressure / Vacuum
• Overfilling
• Rollover (LNG)
• Leaks from pump head flanges
• Gas detection difficult due to high winds at tank top
• Jet Fire
• Short duration after pump stops
• Pool fire
• Pool formation avoided by sloping/ drainage to
downcomer and impounding basin.
• Ignited PSV Release
www.tge-gas.com Page 9Rev1_2020
SEND-OUT SYSTEM
• Liquid send-out
• Truck loading
• Ship / barge loading
• Bunkering (LNG)
• Railcar loading
• Gaseous send-out
• To local low / high pressure mains pipeline
www.tge-gas.com Page 10Rev1_2020
HAZARDS ASSOCIATED WITH TRUCK LOADING
• Human Factors
• Manual or automatic control systems?
• Operation by truck driver / terminal
personnel ?
• Interface between terminal & truck
• Different truck designs
• Overfilling & overpressure protection-
ensured by terminal and truck systems.
• Frequent connection/ disconnection
• Hard arms or flexible hoses?
• High potential for leaks
• Many loading bays → congested area
OX Ethylene Terminal, China
www.tge-gas.com Page 11Rev1_2020
• Submerged Combustion Vaporisers
(SCV)
• Open Rack Vaporisers (ORV)
• Ambient Air Vaporisers (AAV)
• Intermediate Fluid Vaporisers
• Other …
GAS SEND-OUT SYSTEM
The choice of re-gasification system depends on fluid to be gasified, location,
ambient conditions and availability of heat transfer fluid.
ORV. Reganosa LNG Terminal. Spain
www.tge-gas.com Page 12Rev1_2020
• High pressure pumps to meet required pipeline pressure• Potential for large, high pressure liquid releases• High pressure 2-phase / gas jet fires
HAZARDS ASSOCIATED WITH GAS SEND-OUT SYSTEM
• Design pressure (DP) of external mains pipeline
• Terminal piping able to withstand maximum pump shut-off pressure, but no control over design of external pipeline.
• High Integrity Pressure Protection System (HIPPS) might be required
• Material selection downstream of vaporiser• Cryogenic lines usually stainless steel. Gas pipeline usually carbon steel• Need to protect from liquid breakthrough - how far from vaporiser?• Reliance on Safety Instrumented Systems
• Vaporisers can create large congested areas (specially for AAV)
www.tge-gas.com Page 13Rev1_2020
FIRE & COLD EMBRITTLEMENT PROTECTION
• Fire Hazard Assessment (FHA) identifies
equipment and structures to be protected
• Main objective: minimise the risk of escalation
• Informs the selection of:
• Fire, gas and spill detection systems
• Need for automatic ESD
• Passive Fire Protection (PFP)
• Active fire protection
• Embrittlement protection – avoid contact of
critical steel structures with cryogenic fluids.Shenzen LNG Terminal. China
www.tge-gas.com Page 14Rev1_2020
ACTIVE FIRE PROTECTION
• Best fire fighting is to remove the fuel
• Rapid isolation and shut-down.
• Minimise inventories
• Water cooling of equipment and structures subjected to high
thermal loads.
• Contain spills in impounding basins.
• Reduce dispersion & thermal radiation by using foam/foam blocks.
Shenzen LNG Terminal. China
OX Ethylene Terminal, China
www.tge-gas.com Page 15Rev1_2020
The safe design of a liquefied gas terminal requires a multidisciplinary approach
between process safety, process design, plant design, structural and
instrumentation engineers.
This can achieve a design that offers maximum reliability, operability and safety.
CONCLUSION
www.tge-gas.com Page 16Rev1_2020
Thank you for your attention!
www.tge-gas.com Page 17Rev1_2020
Is there a real need for a impounding basin to collect spills
from full containment LNG tanks? Considering that:
▪In-tank pumps in vertical columns
▪Piping is largely welded after the pump head flange
Q & A
www.tge-gas.com Page 18Rev1_2020
LINKEDIN@TGE Gas Engineering
TWITTER@TGE_Gas
YOUTUBE@TGE Gas Engineering
CONTACT Karina.AlmeidaLeñero
@tge-gas.com