Designed and commissioned by The Randall Corporation of USA, in 1982

Production capacity : 55000 MT of LPG 25000 MT of Condensate Gas throughput : 2.21 MMSCMD Feed Gas Pressure : 14 Kg/ Cm2 g Residue Gas Pressure : 11.2 Kg/ Cm2 g Water content : Saturated LPG Quality : To conform IS-4576:1999 specification

The LPG Recovery Plant:

Feed gas composition (mole%)

COMPONENT DESIGN PRESENT FLUCTUATION N2 0.26 0.93 0.44 CO2 1.10 0.64 1.15 C1 86.80 86.58 88.99 C2 6.50 3.75 4.31 C3 3.30 2.16 2.39 i- C4 0.72 0.48 0.56 n-C4 0.86 0.65 0.83 i- C5 0.18 0.23 0.31 n-C5 0.13 0.17 0.26 C6 + 0.15 0.39 0.77

Production profile

Fin. Year : 1992 – 2004 2006 - 2010 2011-2012 * LPG (MT) : 50417- 55780 43750- 48165 50500 COND (MT) : 23470 – 27905 23630 – 25615 29000 LPG (TPD) : 148.68 – 160.24 129.82 – 135.80 150.77 COND (TPD) : 69.45 – 78.61 70.12- 75.36 86.53 Low production was attributed mainly due to change in feed gas composition, more particularly decline in propane and butane content from the year 2006-07. * April – May ‘ 2011

PRODUCTION PROFILE 1992-200455780 54610 54320

24750 25350

0100002000030000400005000060000

1992-93

1993-94

1994-95

1995-96

1996-97

1997-98

1998-99

1999-00

2000-01

2001-02

2002-03

2003-04

FINANCIAL YEAR

MT

LPG PRODUCTION CONDENSATE PRODUCTION

PRODUCTION PROFILE 2006-2010

4375048165 47610 44950 45010

23630 25615 25295 24150 25170

0100002000030000400005000060000

2006-07 2007-08 2008-09 2009-10 2010--11

FINANCIAL YEAR

MT

LPG PRODUCTION CONDENSATE PRODUCTION

RATE OF PRODUCTION 1992-2004235.73235.16 231.58

0.0050.00

100.00150.00200.00250.00

1992-93

1993-94

1994-95

1995-96

1996-97

1997-98

1998-99

1999-00

2000-01

2001-02

2002-03

2003-04

FINANCIAL YEAR

TO

NN

ES

PE

R

DA

Y

LPG PRODUCTION RATE CONDENSATE PRODUCTION RATETOTAL LIQUID PRODUCTION RATE

RATE OF PRODUCTION 2006-2011

150.87

86.86

199.94 203.25 210.71 208.76 210.12237.73

0.00

50.00

100.00

150.00

200.00

250.00

2006-07 2007-08 2008-09 2009-10 2010--11 2011-12

FINANCIAL YEAR

TO

NN

ES

PE

R D

AY

LPG PRODUCTION RATE CONDENSATE PRODUCTION RATETOTAL LIQUID PRODUCTION RATE

Need Of The Hour To find out ways and means to enhance the LPG production from the available feed gas or from the new gas finds which was under development, in order to sustain the market demand in the northeast.

Action initiated for enhancement of LPG Production

Awarded a consultancy service to EIL on 26.10.2006 to prepare Techno Economic Feasibility Report (TEFR) with additional recovery of propane and/ or spiking of butane in OIL’s LPG Recovery Plant at a cost of Rs 36.00 Lakh. Report submitted by EIL on 12.03.2007 and a presentation was given to OIL Directors on 21.03.2007. Further study was carried out by EIL for recovery of propane without considering the limitations of existing plant and equipment and with no butane injection.

Action initiated for enhancement of LPG Production

On 25.04.2007 EIL presented their findings to OIL

Directors wherein the following case studies over base case towards maximizing propane recovery have emerged.

Base case:

• Simulation was carried out on existing plant operating data of 08.11.2006

• Throughput : 79 MMSCFD • Butane content : 1.20 % • Propane recovery :69.7% over the feed content. • LPG production : 135 tones per day (45000 MT) • Propane : Butane : 50.6:49.4 by weight.

Modified Case : Maximization of Propane recovery

Recycling a part of product condensate (NGL) through

deethanizer and debutanizer. • Additional column height of deethanizer (about 1.5 meter) • Small supplementary condenser and re-boiler • A manhole has to be provided for inspection of the tower. • Propane recovery : 87 % • Additional LPG production : 6166 TPA • Propane: Butane : 56:44 by weight. • Expected plant downtime : 3-4 weeks • Project cost: Rs 2-3 Crore • Net Annual revenue : Rs.1520 Lakh based on LPG price @ 27000/MT • Investment will be returned in 100 days.

The road map towards implementation of the NGL Recycle

Project • Preparation of basic design engineering package (BDEP) • Project management consultancy (PMC)

• Procurement and construction

• Installation and commissioning

ACTION PLAN

Award of BDEP with extended deliverables to EIL on

26.05.2007 at a cost of Rs 75 lakh BDEP Report submitted on 15.02.2008 The total estimated cost works out to Rs. 624.75 lakh with

following beak-up. --------------------------------------------------------------------------- 1. Equipment and Modification job : RS. 414.75 Lakh 2. Project Management Consultancy : Rs. 110.00 Lakh 3. Additional job : Rs. 100.00 Lakh --------------------------------------------------------------------------- TOTAL : Rs. 624.75 Lakh

ACTION PLAN

• LOA awarded to EIL for PMC on 10.05.2008 at a cost

of Rs.135 lakhs. • Procurement of equipment initiated. • Tender document for LSTK job (NIT) prepared. • The cost of LSTK has been increased from that was

estimated in BDEP by EIL, R& D in 2007.

• Total cost of the project : Rs.1053 lakhs. (2010)

INNOVATIVE PROCESS

Composition 56:44 of C3:C4 by Wt.

C2 present 1% by Wt.

Vapor pressure 9.5 Kg/Cm2g at 40o C

Yield of the process : 15 Tones per day of additional LPG. (Expected) Specification of LPG :

Recycling one part of NGL (Condensate Product) as Deethanizer Feed Additional Propane can be retained at Deethanizer and subsequently Extra amount of LPG can be produced from Debutanizer top.

Modification Jobs : At a Glance PV 16.09 to be cut at top dished end. Weld 1.5 M height of column section. Steel lining at dished end and the new section. New distributor plate at top section. New reflux nozzle at top section One manhole at new section. Three hand hole for removal of packing at bottoms of section. One new nozzle for NGL recycle at middle section. Contd

Modification Jobs : At a Glance

Replacement of Deethanizer reflux line from pump to the tower.

Topping of packing if necessary.

Replacement of PV 16-08 with new one.

One NGL tank will be installed

Two nos. of pumps for NGL recycle will be required.

Three nos. of new heat exchangers will be installed.

Deethanizer reflux condenser no2

Debutanizer reflux condenser no 2

Debutanizer feed pre heater

HE 15.04 will be replaced with a new one.

HE 15.05 will be replaced with a new one.

Piping modification for new equipment and insulation

STATUS AS ON 01.06.2011 1. Pressure Vessels (3 Nos.) : Received. 2. Heat exchanger (6 Nos.) : Received. 3. NGL dosing pump (2 Nos.) : Received 4. Pressure Control Valves (8 Nos.) : Received. 5. Control Valves ( 4 Nos.) : Received. 6. Safety Relief Valves ( 2 Nos.) : Received 7. Column Internals : Delivery by 30.09.11. 8. LSTK job : NIT is ready 9. PMC Job : Extended up to 31.03.10 10. Expenditure incurred : Rs 3.00 Crore

PV 16 03 PV 16 04

PV 16 01

PV-16 06

FC 2101

PV 16 02

PV 10 08

PV 16 10

PV 16 07

FC 2102FC 2103

HE 15 03

HE 15 08

HE 15 11

HE 15 10

HE 15 01

HE 15 02

CM 11-01

EC 12-01HE 15 09

HE 15 13

HE 15 12

HE 15 05

HE 15 06CONDENSATE

LPG

HE 15 07

RESIDUE GAS

INLET GAS

REFLUX

EXP SEP

COLD SEP

PV 16 09 PV 16 11LPG RECOVERY PLANT PROCESS FLOW DIAGRAMDrawn by: SANCHITA BANERJEE : 29.11.2006

GASOLINE PRODUCT

FROM DEEHYDRATOR

PV1609

PV1610

PV16101A/B

PM17101A/B

HE1512

HE 1504 HE1502

HE 15101

HE 15103

He151 02

HE1505

HE1503

REFLUX

EXP SEP

NGL

COLD SEP

HOT OIL

PV1611

HE1501

TO COLD SEP

FROM EXP SEP TOP

FROM COLD SEP BOTTOM

INLET GAS FROM CM1101

RESIDUE GAS TO HE15102

HE 1506 CONDENSATE

HE1513

PM1703/04

TO KOD

LPG PRODUCT

HE1510

PV1608

TO HE1511

FROM EXP SEP

NGL

RESIDUE GAS

RESIDUE GAS

MODIFIED PORTION

NGL RECYCLE AT LPG PLANT

PM170102

Present consideration Plant can handle a total liquid (LPG + Condensate) of 250-255 tones per day

About 40 MT of NGL will be recycled through Deethanizer and Debutanizer to produce about 17 MT of additional LPG at base case (total liquid will be 135+68+40+17 = 260 MT)

Present production of liquid (152+ 88) 240 MT.

A margin of only 15 – 20 MT left for NGL recycle and additional production of LPG . If LPG production goes to about 160 MT and above there will be hardly any margin left for NGL recycle.

Further Deethanizer and Debutanizer are due for replacement in 2015 – 2017 as per health survey report by EIL

While simulating the base case for enhancement of LPG production the limitation of existing equipment was not considered particularly the case for Debutanizer Rebioler.

Replacement of equipment to be planned phase wise