Prigorodnoye LNG Overview Unit 1000 Inlet Metering Feed gas from the OPF enters unit 1000 between 65 to 95 bar at ~20 o C. The gas leaves the unit at 60 bar at temperature of ~0 o C. The feed gas from U1000 is fed to U1100. Unit 1000 consists of three parallel meter runs, each consisting of a feed gas mono-cyclone separator (V-1001A/B/C), and a flow/pressure control station. This maintains the feed gas supply pressure at 60 bar to the LNG plant. Each meter run is capable of supplying 33.3% of the overall design gas Flow for the two LNG trains.
Prigorodnoye LNG Overview U-1000 Gas Inlet and Metering Gas Pipeline From OPF V1001 A/B/C gas separators with flow & pressure control
Prigorodnoye LNG Overview Unit 1100 Acid Gas Removal unit. Purpose of the Acid Gas Removal unit is to remove CO 2 and H 2 S from the natural gas. Why? To prevent freezing and blockages in the liquefaction unit (U1400). Each train has its own dedicated acid gas removal unit. The solvent used in the unit is Shell Sulfinol D. The solvent is made up of the following: Water 25%. Di-isopropanolamine (DIPA) 50%. Tetra-hydrothiophene-dioxide (Sulfolane) 25%.
Prigorodnoye LNG Overview U1100 Sulfinol Treating Substation Elec/Inst U-1100 Acid Gas Removal Unit
Prigorodnoye LNG Overview U-1100 Acid Gas Removal Unit C-1102 – Regenerator C-1101 – Absorber V-1101– Feed Gas Knock-out Vessel V-1103– Regenerator Overhead Accumulator
Prigorodnoye LNG Overview Transporting C1101 for installation during construction
Prigorodnoye LNG Overview C1101 C1102 Raw gas U1000 Treated gas to driers GAS SEPARATOR V1102 Heat In CO2 Out U1100 Principle Operation Rich amine Lean amine To fuelgas CO2 is soaked up by the amine and removed in the regenerator Absorber Regenerator
Prigorodnoye LNG Overview Purpose of U1300/U1350 Dehydration unit 1300 To remove water present in feed gas from Unit Why? To prevent downstream equipment blockage and damage by ice and hydrate formation during the gas liquefaction process. Mercury removal vessel 1350 To remove trace quantities of mercury that could be present in the feed to liquefaction. Why? To prevent corrosion in the downstream equipment, and aluminium tube bundles of the MCHE ’ s.
Prigorodnoye LNG Overview Substation Elec/Inst U-1300 Dehydration Unit and U-1350 Mercury Removal
Prigorodnoye LNG Overview FAR, Substation and Analyzer House SS-410FAR 1 ANC-1
Prigorodnoye LNG Overview Purpose of Unit 1400 In unit 1400, the feedgas is progressively cooled until it condenses at around –158 degrees C and is subcooled to –162 before running down to the storage tanks. This reduces the overall volume around 600 times allowing one LNG tanker able to carry 600 times more than if the natural gas remained in a gaseous state. (135,000m3 LNG = 81,000,000m3! gas)
Prigorodnoye LNG Overview REFRIGERATION PRINCIPLES Compressing a gas makes its pressure and temperature rise because of the energy we have given it. Depressuring this gas again would result in the pressure and temperature returning to the same point as we started. We have not changed this gas in anyway!
Prigorodnoye LNG Overview REFRIGERATION PRINCIPLES We can graph this and see exactly what has happened. HOT COLD 0 Temperature Pressure 0%100% 0% Compression LOW HIGH
Prigorodnoye LNG Overview REFRIGERATION PRINCIPLES This time, after compressing the gas we will cool it to remove the heat energy we gave it. HOT COLD 0 Temperature Pressure 0%100% 0% Compression LOW HIGH
Prigorodnoye LNG Overview REFRIGERATION PRINCIPLES This time when we depressure the gas the temperature becomes very low! HOT COLD 0 Temperature Pressure 0%100% 0% Compression LOW HIGH Additional temperature drop
Prigorodnoye LNG Overview TREATED FEEDGAS LIQUIFIED NATURAL GAS MR LP HP -180 LNG PLANT PRINCIPLES PMR HP LP LIQUID GAS -80
Prigorodnoye LNG Overview Treated feed gas from the mercury removal unit (U1350) is cooled against low pressure PMR in E-1402 and fed to the scrub columns. The scrub columns, C-1401 & C-1402, remove heavy hydrocarbons (C5+) and the LPG’s from the natural gas stream for 2 reasons. These gases will condense too early in the fractionation section The LPG’s are used as the refrigerant in U1400 cooling circuits. The bottom product of the scrub columns is fed to the fractionation unit (U1500). Purpose of Unit 1400
Prigorodnoye LNG Overview Substation Elec/Inst Purpose of Unit 1400 (Cold End)
Prigorodnoye LNG Overview Process Description - PMR PMR The PMR (pre-mixed refrigerant) system utilizes pressurized PMR, a mixture of ethane and propane, evaporating at two pressures. This supplies refrigeration to the NG feed circuit, the MR circuit and the fractionation unit. The PMR is compressed by gas turbine driven PMR compressor K1440, power assisted by PMR compressor helper motor/generator (KM-1440).
Prigorodnoye LNG Overview Substation Elec/Inst Process Description - PMR
Prigorodnoye LNG Overview MR – Mixed Refrigerant The refrigeration to fully liquefy the feed gas is provided by MR (mixed refrigerant). This is a mixture of nitrogen, methane, ethane and propane. The MR system is a closed loop refrigeration system utilizing two compressors in series, K1420/30. They share a single shaft and are gas turbine driven. The LP MR compressor (K-1420) is a single stage axial machine and the HP MR Compressor (K ‑ 1430) is a two stage centrifugal machine. The MR compressor starter/helper motor (KM ‑ 1420) is used for starting the compressor, and also to provide additional shaft power to maximize LNG production. Process Description - MR
Prigorodnoye LNG Overview Substation Elec/Inst Process Description - MR
Prigorodnoye LNG Overview Process Description - End Flash System End Flash System Nitrogen in the LNG stream leaving the MCHE’s is removed in the end flash vessel. The nitrogen and some light hydrocarbons leave the top of the end flash vessel and exchange cooling in the light MR/end flash gas exchanger. The gas is then compressed by the end flash gas compressor (K- 1450) and routed via the end flash compressor after-cooler to the HP fuel gas system.
Prigorodnoye LNG Overview K-1450 End Flash Compressor
Prigorodnoye LNG Overview U1500 Process Description Purpose of Unit 1500: To remove heavy components from the feed gas To extract refrigerant components, and make up ethane and propane for storage. Also to produce stabilized condensate for re-injection in the crude oil. Any LPG ’ s not used in the refrigerant circuit are re-injected back into the liquefaction section as part of the LNG rundown.
Prigorodnoye LNG Overview The ethane and propane/PMR storage systems are common to both LNG Trains and are used primarily to supply start-up refrigerant for the PMR and MR cycles in the Liquefaction Unit, U The purpose of Unit 1600 is to provide storage for refrigerant grade ethane and propane produced in Unit 1500 De-ethaniser and the De-propaniser. U1600 Process Description
Prigorodnoye LNG Overview LNG Storage Tanks T-3101 LNG Tank No. 1T-3102 LNG Tank No. 2
Prigorodnoye LNG Overview To store and load Liquefied Natural Gasand to collect and compress the vapor generated from the process of filling the tanks. This is known as BOG (boil off gas) Vapor created when loading LNG ships (ship vapor return) is used used as fuel gas LNG Storage Tanks / Boil Off Gas
Prigorodnoye LNG Overview There are two LNG Storage tanks each with a capacity of 100,000m3 Eight loading pumps each with a discharge capacity of 1250 m3/Hr One boil off compressor with a capacity of 730T/D There are Four loading arms, Two for LNG liquid, One vapour return arm & a spare for either liquid or vapour service allow ship loading to be carried out based on a 24 hour turn around. LNG Storage Tanks / Boil Off Gas
Prigorodnoye LNG Overview Fuel gas system K3401 Boil off gas FLAREFLARE T3100 V3401 Boil off gas header TC LC PC Vapour Arm Loading Arm LNG Loading line End Flash compressor
Prigorodnoye LNG Overview Unit 6200 Flare system Emergency Flare stack Liquid disposal burners and Ops flare
Prigorodnoye LNG Overview Why do we have a Flare System? The flare system is used to collect and dispose vapour and liquid in a safe manner. ( Safe disposal of Hydrocarbons, the first system online and the last system shut down) Flare Systems Emergency operational system for cold, light, dry streams, liquid and vapour. Emergency operational system for warm, heavy, streams, liquid and vapour. Emergency operational system for LNG storage and loading, vapour. Operational flare system, vapour. LNG disposal system, liquid and vapour (start-up). Spare flare can be used for cold and warm service. Unit 6200 Flare system FLAREFLARE
Prigorodnoye LNG Overview Warm Flare System (FWW) All the warm vapours are collected into a single 48” header which slopes to the liquid knock-out drum V The header is continuously purged with LP fuel gas at sufficient flow rate to keep velocity at the tip of flare stack. Nitrogen connection is also given as back-up purge source. Warm Liquid Disposal System (DHC) The warm liquids from manual drains are collected in a 4” header and routed to V Light components are flashed-off and burned in A-6201 (FWW) The accumulated liquid in V-6201 is pumped and transferred to warm liquid burner A-6204 by P-6201A/B via 6” line. Unit 6200 Flare system
Prigorodnoye LNG Overview Cold Flare System (FCD) Cold dry and light hydrocarbon vapours from unit 1400, 1500 and 1600 are collected into a 48” header which slopes to the cold flare KO drum V-6202.The header is continuously purged with LP fuel gas. Nitrogen connection is also given as back-up purge source.Vapour from the cold flare KO drum is directed to the cold flare (A ‑ 6202) through a 56” line. HP fuel gas is used as atomising gas to flare stack A-6202 Cold Liquid Disposal System (DLH) All the cold liquids are collected into two 12” headers that are routed to the cold flare KO Drum (V ‑ 6202). flashed vapours are removed and burned in A Operational Flare System (FOP) Any operationally initiated release is vented to a separate 16” FOP header. The vented gas is routed to V-6203 and burned in operational flare (A-6211) Unit 6200 Flare system
Prigorodnoye LNG Overview Unit 6200 Flare system
Prigorodnoye LNG Overview Unit 6200 Flare system