Transcript 4_Bapiraju_CPCL

PETROFED Work Shop on
Energy Management & Efficiency Improvement
in
Oil & Gas Sector
Oxy Enrich Process for Capacity
Enhancement of Claus Based
Sulfur Recovery Unit
NOVEMBER 13, 2009
NEW DELHI
OxyEnrich Process
• OxyEnrich Process uses oxygen enriched air for oxidation
of H2S to elementary sulfur in sulfur recovery unit and
increases the plant capacity.
• Process minimizes nitrogen content in combustion air
and results reduction in process gas flow in down
stream of reaction furnace .
• Process increases reaction furnace temperature, which
depends on oxygen concentration in air .
• Process gives better conversion of H2S in reaction
furnace and marginally increases overall sulfur recovery
of the unit
MAIN DRIVERS FOR OPTING SULFUR REVAMP IN CPCL

ADDITIONAL ACID GAS GENERATION OF ABOUT 16%
DUE TO NEW PROCESS UNITS BEING INSTALLED UNDER
THE
EURO- IV PROJECT

AVAILABILITY OF VERY MARGINAL CAPACITY IN THE
EXISTING UNITS ABOUT 10%

REQUIRED CAPACITY LEVELS OBSERVED TO BE (ABOUT
30 TPD) NOT COST EFFECTIVE COMPARATIVELY , IF NEW
UNIT OPTION IS ADOPTED

SCOUTED FOR VIABLE OPTIONS FOR MARGINAL
AUGMENTATION

REQUIREMENT OF QUICK AND LOWER COST OPTIONS IN
HAND
DEMONSTRATION RUN OF OXYGEN ENRICHMENT IN
SULFUR RECOVERY UNIT OF CPCL
SALIENT FEATURES:
 Technology is First of its kind being implemented in Indian
Refineries.
 Project jointly undertaken by CPCL & EIL (R&D).
 Technology will be jointly licensed by CPCL & EIL.
 Demonstration Run being done by CPCL from 11/5/2009
 No Major hardware modifications in the existing unit.
 Capacity increase by 15% to 22%
(From 90 TPD to 104 / 110 TPD of Sulphur in each Train)
 Oxygen content in Air Enriched from 19.6 to 28 vol%
 Low cost option for enhancing SRU capacity.
 Cost towards demonstration run is about Rs.2 Cr.
Slide 4 of 8
MAJOR MILESTONES OF DEMONSTRATION RUN
SNO
ACTIVITY
DATE
1
Signing of MoU with EIL
25-09-07
2
Process Package Developed by EIL
25-10-08
3
Detailed Engineering Activities carried out by EIL
25-10-08
4
Installation of Piping & Control Valves
30-04-09
5
Oxygen Mixing Drum installation
07-05-09
6
Successful Commissioning of the System
11-05-09
Slide 5 of 12
Major Benefits of OxyeEnrich Process
Greater processing
capacity of sulfur
recovery unit
Stable flame in
main burner even
at lean acid gas
processing
Low capital cost for
grass root sulfur
units due to smaller
equipment sizes
Less sulfur mist–
lead to better
operation
No major modification
for 25% -30% capacity
enhancement
Processing low
quality feed
without problem
Low backpressure
ensures trouble
free operation
Conventional Claus Process
Claus SRU Configuration
Thermal
Catalytic
Stages
Stage
To Steam
System
AAG K.O.
Drum
HP
Steam
BFW
Amine Acid
Gas Feed
HP
Steam
#2
Reheater
#1
Converter
Steam
Drum
Thermal Reactor
(Reaction
Furnace)
HP
Steam
#1
Reheater
#3
Reheater
#3
Converter
#2
Converter
To
Condensate
System
To
Condensate
System
To
Condensate
System
Waste Steam
Condenser
Rxn Cooler
(WHB)
Burner
To Steam
System
To Steam
System
To Steam
System
#1
Condenser
#2
Condenser
#3
Condenser
To TGTU
SWS GAS
K.O. Drum
SWS Acid
Gas Feed
BFW
Combustion
Air Blower
Sulfur to
Pit
BFW
Sulfur to
Pit
BFW
#4
Condenser
Sulfur to
Pit
BFW
Sulfur to
Pit
O2 Enrichment : Direct O2 injection to Combustion Air
Acid Gas Preheater
Acid Gas from
Burner
Furnace
WHB
Catalytic
Stages
ARU/SWS
Mixer
Combustion air from Blower
Oxygen from Oxygen
Supply System
RATIO CONTROLLER
O2STORAGE
VESSEL
FIC
UV
FV
O2VAPORIZER
O2 ANALYZER
FIC
AIR BLOWER
MIXER
FIC
ACID GAS
MB
MAIN
COMBUSTION
CHAMBER
PROCESS
GAS
FOR
SULPHUR
RECOVERY
Case Study for OxyEnrich Process

Plant Capacity

Typical Feed Composition
H2S
H2O
H2
CH4
C2H6
NH3
%V
%V
%V
%V
%V
%V
: 65 TPD
Acid Gas H2S rich SWS NH3 rich SWS
93.40
66.53
2.69
4.43
33.37
42.00
0.07
0.00
0.00
0.06
0.00
0.00
2.04
0.00
0.00
0.00
0.11
55.30
Furnace Temperature ( C )
Result : Effect on Furnace Temperature
1500
1450
1400
1350
1300
1250
1200
1150
1100
Oxygen Concentration in Enriched Air(Molefr.)
Air Flow rate Kmole/hr
Result : Effect on Combustion Air Rate
250
200
150
100
50
0
Oxygen Concentration in Enriched Air (Molefr.)
Combustion Air Flow Rate
Total Combustion Air to MCC
Oxygen injected in Air
Result : Capacity Enhancement
Oxygen Concentration in Enriched Air(Molefr.)
Technology Demonstration : Feed / Controlling Parameters
Feeds



Acid Gas
 Source
 H2S concentration
Vaporised Oxygen
 Source
Combustion Air
 O2 concentration
: Amine Regenerator O/H
: 74-90%v
: Liquid Oxygen Storage Vessel
: 19.6-28%v
Controlling Parameters



Temperature of Reaction Furnace Effluent
 Maximum allowable temperature
: 1500oC
Backpressure of the unit
 Maximum allowable pressure
: 0.74 Kg/cm2
Sulfur recovery of the unit
 Minimum sulfur recovery
: 99%
Technology Demonstration : Capacity Enhancement of CPCL-SRU
Objectives :
 Demonstration of OxyEnrich Process in a commercial plant
 Commercial use of OxyEnrich Process for processing additional
acid gas to be generated in Euro IV Project
Existing SRU

Process
: MCRC

Design Capacity
: 90 TPD Sulfur

Design Sulfur Recovery : 99.0% ( min)
Technology Demonstration : Plant Configuration After Revamp
Oxygen
Air Blower
Liquid Oxygen Vaporization Unit
Air
Acid
LP Steam
Acid Gas, Air , Fuel Gas
RF
WHB
Gas
Condenser-I
Claus
Reactor-I
Line Burner
Claus Bypass
LP
Reheater
Fuel Gas
S
MCRC-I
Condenser-III
MCRC-II
Condenser-IV
MCRC-III
Condenser-II
T
LP Steam
A
Condenser-V
C
K
Sulphur
Incinerator
Air , Fuel Gas
Technology Demonstration : Steps in Project Execution
• Adequacy check of equipments/instruments through test
run and in-house simulator
• Preparation of Process Package for oxygen enrichment
facility
• Procurement of Equipments like Control valves, Oxygen
Analyzer, Oxygen Supply and storage system etc.
• Installation and Erection of oxygen mixing device and
oxygen supply system
• Commissioning of Oxygen enrichment system and test run
Technology Demonstration : Key Operating Data
OPERATING PARAMETERS
BEFORE
(Oxygen
Enrichment )
AFTER
(Oxygen
Enrichment)
Feed Gas Flow ( Acid Gas), Nm3/Hr
2115
2600
Enriched Air Flow, Nm3/Hr
3900
3100
Oxygen Content in Enriched Air, vol %
19.6
26.8
MCC Temperature, °C
1160
1340
Unit Back Pressure, kg/Cm2
0.71
0.71
% Increase in Unit Throughput
NA
22
Above 99
Above 99
4.20
5.60
Sulphur Recovery, %
Steam Production, MT/Hr
Technology Demonstration : Salient features
No Major
hardware
modification
Low cost option
for enhancing
SRU capacity
Improvement in
MCC Temp and
stable flame even at
Lean acid gas
Low
backpressure in
the unit
Capacity
increased by 22%
Oxygen content
in Air Enriched up
to 26.8 vol%
Quality of
Sulphur
continued to be
good
EIL-CPCL Deliverables for Implementation of OxyEnrich Process
Supervision of test run for performance evaluation of running SRU
Adequacy check of Existing Equipments & Instruments
Preparation of Process Package for oxygen enrichment facility
Detail Engineering of new oxygen enrichment facility
Commissioning