COREFLUX®

Enhanced NGL/LPG Recovery
The solution for NGL/LPG extraction from NaturalGas and LNG with high product recovery rate and low
energy consumption

COREFLUX® Concept
Toyo Engineering Corporation (TOYO) has developed COREFLUX®
(Cold Reflux) technology to extract Natural Gas Liquids (NGL),ethane and Liquefied Petroleum Gas (LPG) from Natural Gas/
Liquefied Natural Gas (LNG) using a reflux enhancement method.
Our unique processes are known as COREFLUX®-C2 for NGL recovery from Natural Gas, COREFLUX®-LNG for ethane and LPG
recovery from LNG and COREFLUX®-LPG for LPG recovery fromLNG.
Key features of COREFLUX®-C2/LNG concept are ;▶
Simple flow scheme- lower CAPEX▶
High ethane recovery rates▶
Low total energy consumption with advanced cold heat
integration and lower OPEX compared to conventional NGL
extraction processfrom the separator is recompressed by a compressor and totallycondensed against the cold stream from demethanizer overhead.
The condensed liquid contains high concentration of methane
and works as an effective reflux. Maximum power recovery at theturbo expander and the methane rich reflux lowers total compression power by 20% compared to the conventional processes.

Brakecompressor

Sales gas

Turboexpander

Naturalgas feedColdrefluxcompr.

C3 refCold
separator

COREFLUX®-C2 Features & Applications
COREFLUX®-C2 is a highly efficient and competitive process technology with a deep NGL recovery from Natural Gas, oil associated gas and off-gas from refinery plants. This proprietary process
suits following applications ;▶
High ethane recovery requirement▶
Rich feed gas▶
Increased throughput or enhanced C2 recovery
COREFLUX®-C2 recovers more than 95% of ethane from feed natural gas at less compression power compared to the conventional split vapor process. Easy modification from the conventional
process to COREFLUX®-C2 is also applicable. NGL recovered will
be utilized for petrochemical feedstock and contribute to feasibility of gas processing complex.

Demethanizer
NGL

Fig.-1 : Flow scheme of COREFLUX®-C2

COREFLUX®-LNG Features & Applications
COREFLUX®-LNG is an efficient LNG processing technology to recover ethane and LPG from LNG. Process features in COREFLUX®LNG include ;▶
High ethane recovery rate ( > 98%) with enhanced reflux▶
Low energy consumption with cold heat integration▶
Simple flow scheme for easy operation and maintenancewith low initial investment

COREFLUX®-C2 Process Configuration

COREFLUX®-LNG Process Configuration

Process configuration of COREFLUX®-C2 is shown in Fig.-1. Turbo
expander cools down the feed gas similar to the conventional
split vapor process, however in COREFLUX®-C2, all feed gases aresent to the turbo expander to maximize the power recovery. To
produce a methane rich reflux, a gas-liquid separator is provided
at the outlet of the turbo expander. The methane rich vapor

Process configuration of COREFLUX®-LNG is shown in Fig.-2.
Process feature in COREFLUX®-LNG is in demethanizer overheadcondenser system, where the overhead vapor is partially condensed against the cold LNG feed stream in the conventional
process. In COREFLUX®-LNG, a part of condensed liquid fromthe condenser is returned to demethanizer as reflux. This reflux

COREFLUX® Enhanced NGL Recovery

contains more than 99 mole% of methane, and this methane richreflux enables more than 98% of ethane recovery rate at demethanizer. The remaining vapor from the condenser is compressedwith an overhead compressor before being fully condensed
against the feed LNG. For energy conservation, a methanol heating medium, suitable for cold heat transfer, is applied.

LPG provides additional profit to LNG regasification terminals, i.e.,
an opportunity to sell petrochemical feedstock and improve terminal complex feasibility as depicted in Fig.-4. COREFLUX®-LNG/
LPG is applicable to regasification terminals where:▶
Higher heating value LNG importing▶
Lower heating value Natural Gas to end users▶
Ethane and LPG demand as petrochemical feedstock

Demethanizer
reflux drum

Refluxdrum
Lean LNG
Compressor

Reflux pump

Refluxcondenser

Heating medium(methanol)

Feed LNG
Compressedgas condenser

Feed LNG
pump

Feed LNG

Sidereboiler

Lean LNG

Demethanizer
Deethanizer
Deethanizer condenser
Heating medium(Methanol)

Refluxdrum

Feed LNG pumpSidereboiler

Refluxcondenser

Reboiler

Reboiler

Demethanizer
Ethane,LPG
Recovered LPG

Fig.-2 : Flow scheme of COREFLUX®-LNG

COREFLUX®-LPG Features & Applications
COREFLUX®-LPG is unique LNG processing technology to extract
LPG from LNG, where process configuration is further simplified
from COREFLUX®-LNG. Process features in COREFLUX®-LPG include:▶
High C3/C4 recovery rate ( > 99.5%) with enhanced reflux▶
No external refrigerant for cryogenic fractionation▶
No vapor compression for reliquefaction of demethanizer
overheadFig.-3: COREFLUX®-LPG Process Flow Diagram (Patent pending)

LNG Receiving Terminal

Lean LNG
HydrogenRich LNGNGL Recovery
COREFLUX®-LNG
COREFLUX®-LPG

COREFLUX -LPG Process Configuration®

Process configuration of COREFLUX®-LPG is shown in Fig.-3. A
high Propane recovery rate can be achieved when an ethanerich reflux is fed to the overhead of demethanizer. This is uniqueprocess and first time to use subcooled ethane reflux to enhance
LPG recovery in LNG processing.
Process feature in COREFLUX®-LPG is overhead vapor in bothcolumns is fully condensed by feed LNG and heat recovery fromdemethanizer. This reflux contains more than 99 mole% of ethane to ensure less LPG leakage and enable more than 99.5% ofpropane recovery rate in whole process. All products can be sentout in liquid phase to ensure no further compression becomesrequired.

Applications of COREFLUX®-LNG/LPG
Extracting ethane and LPG at the LNG regasification terminal isan effective method to meet the heating value specifications
with downstream gas pipelines requirements. COREFLUX®-LNG/

To Gas pipeline

Vaporizer
LNG

EthaneEthylene Plant

Ethylene

PE PlantPE

Butene-1
Hexene-1
LPG

PDH Plant

Propylene

PP Plant

PPFig.-4: COREFLUX®-LNG/LPG integration with petrochemical plants

Commercially Proven Process
COREFLUX®-LNG has been selected by Oil and Natural Gas Corporation Ltd (ONGC) for a 5 million tons LNG per annum C2/C3/C4 extraction facility located in Dahej, India. The plant has beenin commercial operation successfully since 2015.
COREFLUX®-C 2 has also been selected by State Concern “Turkmengas” for a 5 billion m³ natural gas per annum NGL extraction
facility located in Turkmenbashi, Turkmenistan. Turkmengas
awarded TOYO as EP contractor for gas processing, ethylene andpolyethylene construction project. This plant is scheduled to becompleted in 2018.

Toyo Engineering Corporation
2-8-1 Akanehama, Narashino-shi, Chiba 275-0024, Japan
TEL: +81-47-454-7317
FAX: +81-47-454-1164
http://www.toyo-eng.co.com
COREFLUX®is a trademark of Toyo Engineering Corporation registered in Japan (Registered Number : 4839760).

2018.03.10②FP