ImmersoJet Burner — IJ-8 v1

Rob Forbes, Eclipse Calgary

Eclipse Product:

Submitted by:

Application:

Description:

Oil Sands Flash Treater

Eclipse was contacted by Universal Industries Corp. (UIC), an operating entity of Foremost Universal LP, in Lloydminster, Alberta, to provide an immersion tube burner system for a new patented design of a flash treater. Universal Industries has been supplying customers with a full line of oil and gas processing equipment since 1949.

The process of evaporation dehydration involves boiling the water out of oil. At atmospheric pressure, water turns to vapour at 100°C (212°F), whereas the oil, except for some light ends, has a higher boiling point. During a conventional heavy oil treating process, free water and the larger droplets of water in the emulsion are removed by application of heat, chemicals and residence time. The remaining emulsion usually contains small droplets of water (up to 10% BS & W).

The UIC/Colt Flash Treater® has been designed to break that remaining emulsion (whether it is a slop feed or the outlet of a conventional treater), which may otherwise be impossible or too expensive to treat. Recovery of this untreatable heavy oil can effectively pay back the UIC/Colt Flash Treater® quickly. The UIC/Colt Flash Treater®

recycles hot dry oil from its outlet to the incoming stream of wet oil. This hot oil will cause a majority of the incoming water to vaporize. The recycling of hot oil, the large volume of oil in the vessel and the baffled heating path enable the UIC/Colt Flash Treater® to handle substantial slugs of water and emulsion without foaming and unstable operation.

The IJ-8 Version 1 was the type of burner that would fit the application, but there were some issues to address to ensure safe and reliable operation in the field.

Overall Side View of Unit Showing Both IJ-8 Burners and Control Cabinets

AB-193

Two important issues are Viscosity and Cracking1. Viscosity - There is a caution in the IJ-8 Installation Guide about highly viscous fluids. We looked at the heavy oil viscosity and found that it is on the borderline of #4 & #5 (light) oil. The Eclipse Engineering Guide shows: #4 fuel oil at 35-160 SSU, 0.85-0.99 spec. grav. #5 (light) fuel oil is 80-700 SSU, 0.89-1.01 spec. grav. The customer’s oil is 100 SSU (20 cP), 1.0 spec. grav. 2. Cracking - Les Unrau, General Manager of UIC describes the cracking process:Cracking is a fairly complex process that is affected by temperature, pressure and retention time. An increase in any of these parameters increases the likelihood of cracking. Conversely, a decrease in one means the others have to be increased for cracking to happen. When done as a process, thermal cracking typically takes place at 700°C (1290°F) and 1000 psi. I don’t think cracking will occur in our application for the following reasons:1. Our pressure is very low (3-5 psig) 2. The bath temperature is relatively low at135°C (275°F). 3. Our typical process vessels, using natural draft burners, have retention times in the order of hours, the units that these power burners are going into have retention times of less than 20 minutes.4. The vessels are large enough and open enough that the hot fluid is not held directly against the fire tubes; it can move away as convective currents and be replaced by new fluid. We further encourage this action by spraying hot oil continuously onto the surface of the tubes through a 2” pipe with jets every foot along each heater tube leg as well as one re-circ pipe along the bottom of the vessel.

End View Combustion Cabinet Inside

David Collier (V.P. Engineering at Eclipse) advised on the Cracking condition and what methods would avoid it:

The main concern is carbon forming on the outside of the tube due to the “oil cracking”. The hottest part of the tube is the end of the combustion chamber and the first section of tube and this is where the oil will crack first. This carbon will form an insulated barrier and cause the high temperature to move down the tube and hence more cracking. If the carbon forms a very effective insulation barrier the tube or combustion chamber will eventually fail.

To minimize the effect I would suggest that you direct the re-circulated oil to flow over the combustion chamber to increase the heat transfer rate and reduce the surface temperature. If 700°C (1290°F) is the cracking temperature, there should be no problem with the ImmersoJet.

With the fluid circulation methods that UIC had provided in the unit to address the heat transfer it was decided to implement a control method to ensure the maximum firing rate is moderated by the heat transfer. Larry Meek (Calgary service technician) suggested a cascaded controller design which was implemented with two Honeywell UDC control-lers.

The temperature control system for the treater is designed to operate using two temperature controllers to provide minimum heat up and recovery time while still protecting the immersion tube from exceeding an operating temperature which may lead to carbon formation.

The first temperature controller, labeled as the Operating Temperature Control, senses the product temperature in the ves-sel. The second temperature controller, labeled as the Stack Temperature Control, senses the flue gas temperature in the burner exhaust stack. The Operating Temperature Control compares the product temperature with the selected Set Point, the output from the Operating Temperature Control is sent to the Stack Temperature Control as the temperature Set Point. This Set Point is designed to operate within a specified set point temperature range. The output from the Stack control-ler to the burner firing rate valve varies to maintain the varying Stack Set Point. This action will continue until the product temperature inside the vessel meets the Operating Temperature Control Set Point. This ensures a slow, controlled heat-up ramp which will reduce the coking of the immersion tube, that reduces tube life.

Deer Creek Energy Flash Treater PrototypeUIC has patented this new multi-pass tube oil treater design and plan to take the lead over their competition. Their past history of these treaters has been with Atmospheric Injector burners in tubes up to 30” diameter for a comparable firing rate, UIC currently has thousands of units in the field.

Eclipse Calgary designed and built a single burner IJ-8, V1 system for UIC to supply for a flash treater for Deer Creek En-ergy. The process vessel has the IJ-8 burner mounted horizontally in a process vessel. This first unit has the control panel, blower and valve train located inside the heated process building which is a Class I, Div. II hazardous area.

Burner firing rate: 5.625 MM Btu/hr Immersion Tube: 4-pass tube, 29 feet long each leg (4x29=119 ft)Oil viscosity: 100 SSU (20 cP), spec. grav. 1.0Incoming fluid temp is 110° – 140° C (230° – 284° F)Process temp is 135° C (275° F)Process high limit temp is 150° C (300° F)Stack controller set point range – -50° C to +260° C (-58° F to +500° F)Stack high limit temp is 300° C (570° F)

Jacques Inkel (technician Eclipse Montreal) provided start up for the system. Process start-up was done by Larry Meek. The burner was tuned with fluid flow and it produced a smooth, controlled temperature ramp to the setpoint of 140° C (284° F). UIC has 6 temperature probes in the vessel and all read within 7° C (45° F) of each other.

Dual Burner DesignEclipse Canada supplied two dual burner units since the first prototype. Each system consists of two IJ-8 V1 burners firing at 6.25 MM Btu/hr in the same vessel for a combined firing rate of 12.5 MM Btu/hr. The other specifications are the same as the Deer Creek Energy prototype. All of the installation photos shown were taken at start-up. The cabinets enclosing the blower’s valve trains and control panels were designed by Harry Ajamian and fabricated in Montreal. We have positive feedback from the Devon Energy operators on the powerful, reliable operation of this treater; it is their first experience with a power burner in this type of process. The initial process throughput is 80 cubic meters per hour of heavy oil. The second dual unit is due to start later this year.

Temperature Control Panel Process Pumps

Below is the data from a combustion analysis test performed with an EGA4 on the first dual burner treater unit that was started in February 2007 at the Devon Energy Manatokan site near Bonneyville, northeast of Lloydminster, Alberta.

Cabinet End View

AB-193

EnglishUnits

Burner Input 1000’s Btu/hr. 1000 2400 3800 5200 6600 8000

Air

Static Air Pressure, tap “A” 1Diff. Air Pressure, taps “A” & “D”

Air Flow

"w.c.

"w.c.

SCFH

0.6

∆0.5

11,500

5.0

∆2.5

27,600

17.5

∆8.0

43,700

21.8

∆8.9

59,800

24.5

∆10.0

75,900

27.0

∆11.0

92,000

Gas

Static Gas Pressure, tap “B” 1Diff. Gas Pressure , taps “B” & “C”

Gas Flow

"w.c.

"w.c.

SCFH

0.6

∆0.5

1000

4.5

∆1.1

2400

11.8

∆1.8

3800

16.9

∆ 2.9

5200

20.5

∆4.5

6600

24.2

∆6.2

8000

SystemImmersion Tube Backpressure 2Min. Blower Pressure Required 3

"w.c.

"w.c.

0.1

9.6

2.5

14.0

9.5

26.5

12.9

30.8

14.5

33.5

16.0

36.0

MetricUnits

Burner Input Kw 291 703 1114 1524 1934 2345

Air

Static Air Pressure, tap “A” 1Diff. Air Pressure, taps “A” & “D”

Air Flow

Pascals

Pascals

Nm3/hr.

149

∆125

308

1246

∆ 623

740

4359

∆1993

1171

5431

∆2217

1603

6103

∆2491

2034

6726

∆2740

2466

Gas

Static Gas Pressure, tap “B” 1Diff. Gas Pressure , taps “B” & “C”

Gas Flow

Pascals

Pascals

Nm3/hr.

149

∆125

27

1121

∆274

64

2939

∆ 448

102

4210

∆722

139

5107

∆1121

177

6028

∆1544

214

SystemImmersion Tube Backpressure 2Min. Blower Pressure Required 3

Pascals

Pascals

25

2391

623

3488

2367

6601

3214

7673

3612

8345

3986

8968

Typical Flue Products

Oxygen

Carbon Dioxide

%

%

12.0

4.9

10.2

6.1

8.3

7.20

6.1

8.3

4.0

9.5

2.8

10.2

Natural Gas, 0.65 s.g. • 15% Excess Air at High Fire • 80% System Efficiency • 1.5" Integral Gas Orifice

IJ-8 Operating Data

Static pressures are for sizing only. Do not use them for burner set-up or adjustment.

Immersion tube sized for 80% efficiency at 8,000,000 Btu/hr. input (2345 kw) using six 90° or three 180° elbows.

Using the corresponding input as high fire for the system. Includes 9" w.c. drop (2239 Pa) taken across item #5, page 3, to aco usticallyseparate the burner from the manifold and blower, minimizing resonance problems.

1

23

Model IJ-8Version 1

ImmersoJet Burner

3/25/04Data 330-8

2 Eclipse ImmersoJet Burner Model IJ-8 v1, Data 330-8, 3/25/04

Design Considerations

Combustion Air PipingKeep piping pressure losses to a minimum. Adding any elbows to the typicalsystem shown on page 3 may require larger piping, system components, or alarger blower to make up for the additional pressure losses. The chart at rightshows high fire air pressure losses that may be expected for elbows of variouspipe sizes.

Gas PipingSee chart at right for high fire gas pressure losses for piping elbows.

For convenience, the gas inlet housing may be rotated in 45° increments withrespect to the air inlet.

Immersion Tube Length vs. Efficiency

Piping Considerations

System Sizing for 80% EfficiencyIt is customary to size conventional immersion tubes for 70%efficiency, a reasonable compromise between fuel economyand tube length. However, small bore tubes occupy less tankspace than conventional tubes, so their length can easily beincreased to provide efficiencies of 80% or more.

Burner SizingDetermine the net heat output required by the tank.

Divide this by the immersion tube efficiency to find the inputrequired to the immersion tube.

Example: A spray wash tank requires 2,800,000 Btu/hr. out-put from the immersion tube at high fire. Design efficiencyis 80%. Dividing 2,800,000 by 0.8 gives an input to the tubeof 3,500,000 Btu/hr.

Immersion Tube DesignTubes sized for 80% efficiency will have low exhaust tem-peratures, causing condensation to form in them at start-up

or during long idling periods. This condensation will normallyevaporate after the burner has run at high fire briefly. How-ever, if extended idling periods are expected, provide a con-densate drain at the exhaust and slope the immersion tubedown away from the burner. Consult Eclipse publication Info330 for details.

Small bore immersion tubes can be sized for efficiencieslower than 80% if tank space is extremely limited or if com-plete freedom from tube condensation is desired.

The graph below shows the immersion tube length requiredto achieve various efficiencies at two different inputs. Tubelength is the total running length measured from the exit(small) end of the combustion chamber. Heat transfer fromthe chamber itself has been taken into account.

Use the centerline lengths of elbows when computing totalpipe runs.

65 70 75 80 85

40

50

60

70

80

90

100

Immersion Tube Efficiency, %

110

120

130

4,000,000 Btu/hr. (1172 kw)

8,000,000 Btu/hr. (2345 kw)

Imm

ersi

on

Tu

be

Len

gth

12

16

18

14

meters

20

22

24

26

28

30

32

34

36

feet140

30

38

40

42

90° Elbow Pressure Drops*

* At maximum input, page 1.

PipeSize

Air

Gas

Loss Per90° Elbow

6" 4.0" w.c.8" 1.4" w.c.

2" 1.3" w.c.3" 0.3" w.c.

3Eclipse ImmersoJet Burner Model IJ-8 v1, Data 330-8, 3/25/04

Leave at least 6" below item 8 for adjustment.

Typical Single Burner Immerso-Jet System

Sized for a high fire input of 8,000,000 Btu/hr.

PilotGas

1

2 3

4

5

6

8

79

Outlet 8"

Inlet6"

Inlet2"

3"

3"

3"

1/2"

1/2"

10

1112

CompanionWeld Flange

(furnishedw/burner)

As ShortAs Possible

As ShortAs Possible

Reducer8" to 6"

6" w.c. minimumrequired here.

Pilot Pressure:

55" w.c. maximum32" w.c. minimum

Contact Eclipse if theminimum is not available.

Main Gas Pressure:

Loading Line1/4" Pipe or3/8" Tubing

Pipe Eclipse EclipseItem Description Size Part # Bulletin

1 Blower, SMJ 8823-15, 40" w.c. @ 92,000 SCFH 8" 202775-1 610with 15 HP motor (included) --- 11220 610

Inlet filter (optional) --- 200754 614

2 Air flow switch, JD-2 with 24" spring --- 16928-1 840

3 Air control motor w/mounting kit --- --- 720

4 Automatic butterfly valve, Eclipse 24 BV-A8D 6" 500998 720

5 Manual butterfly valve, Eclipse 24 BV 6" 500915 720

6 Immerso-Jet Burner, IJ-8 --- 113047 330

7 Adjusting valve, Eclipse 1212-62 ALO-R 3" 302012 728

8 Proportionator, Eclipse 112 ABP 3" 500628 740

9 Pressure gauge or hose cock --- --- 710, 940

10 Adjustable pilot cock 1/2" 10267 732

11 Pilot solenoid 1/2" --- 760

12 Pilot regulator 1/2" --- 680

Dimensions

Notes

1. Flame rod and ignition plug positions are interchange-able. Do not mount them on the bottom port of theburner, as condensation may collect there and causenuisance shutdowns.

2. Specify mild steel or stainless steel for the combustionchamber and discharge pipe.

3. Bolt the outer circle of mounting studs on the combus-tion chamber through holes drilled in the tank wall. Boltthe inner circle of studs to the burner mounting flangethrough holes drilled in the tank wall. See the “TankWall Layout” at right. Use a sealing compound on theliquid side of the tank suitable for the liquid and tem-peratures being used. Consult a local vendor for rec-ommendations.

To weld rather than bolt the chamber to the tank wall,grind off the outer ring of studs from the chamberflange. Do not use a gasket between the chamberflange and the tank wall.

4. For convenience in piping, the gas inlet housing maybe rotated in 45° increments with respect to the air in-let.

Tank Wall Layout

Tank Wall Cutout17-1/2" I.D.

445 mm

Burner FlangeHoles On 20-3/4" B.C.

527 mm

Chamber FlangeHoles on 23" B.C.

584 mm

(16) Holes1/2" Dia.13 mm

45

22.5

9"(229 mm)

Tank Wall

Flame Rod#11941

Tap “D”

Air Inlet6"

(152 mm)

GasInlet

2" N.P.T.

4"(102 mm)

6-1/2"(165 mm)

7-5/16"(186 mm)

17-1/8"(435 mm)

Peepsight

NOTE: All taps are 1/8" N.P.T.

Burner Flange22" O.D.(559 mm)

51-3/4"(1314 mm)

Combustion Chamber10 Gauge

CombustionChamber Flange,

24-1/4" O.D.(616 mm)

Discharge8" Pipe Size

Schedule 40 Pipe

17-3/4" O.D.(451 mm)

Tap “C”

Tap “A”

Tap “B”

IgnitionPlug

#11941

0.38"(9.65 mm)

Data 330-8 3/25/04 Litho in USA