Response of Oil Sands Derived Fuels in Diesel HCCI Operation · 2014-03-10 · Response of Oil Sands Derived Fuels in Diesel HCCI Operation ... A fuel produces ISFC and combustion

Response of Oil Sands DerivedFuels in Diesel HCCI Operation

Bruce G. Bunting

senior staff scientist

Fuels, Engines, and Emissions Research Center

2007 DOE DEER Conference

Sponsored by DOE FCVT, Fuels Technology Program DOE team: Steve Goguen, Kevin Stork, Dennis Smith

Managed by UT-Battellefor the Department of Energy

Oil sands derived fuels: close to home, large supplycompatible with petroleum infrastructuresome chemistry differences

• OUTLINE OF TALK – 2006 vision – Advanced characterization – down to molecular level • how far do we need to go?

– HCCI engine – Fuel performance effects • different chemistry • new opportunities / potential problems?

– Conclusions – Future plans • (We are not done yet!)

2 Managed by UT-Battellefor the Department of Energy 2007 DOE DEER Conference

3 Managed by UT-Battelle

for the Department of Energy 2007 DOE DEER Conference

DEER 2006 vision

Ken Mitchell, Royal Dutch Shell

CO-INVESTIGATORS

Fuels

• Fuels have specifications – Cetane, octane, distillation, vapor pressure, flash point,

stability, etc. • And simple chemistry

– Sulfur, aromatics, olefins • And more chemistry • And are eventually mixtures of individual molecules

– How far do you need to go to control manufacturing and quality?

– How far do you need to go to understand and optimize?


Oil sands fuels and refinery intermediates • Provided by Shell Canada (now Royal Dutch Shell) • 17 fuels and refinery intermediates derived from oil sands crude

– Both coker and hydrocracker upgrading – 33 to 55 cetane – 196 to 336 °C T50 – Diverse chemistry • 3 to 20% normal paraffins • 8 to 19% iso paraffins • 41 to 63% cyclo paraffins • 15 to 38% aromatics, • 0 to 2% olefins

• Majority treated to ultra low sulfur specs – good looking, good smelling – not your father’s oil sands fuels


HC types, molecular weight, polarity M

OR

E PO

LAR

Æ

seco

ndar

y re

tent

ion

time,

sec

onds

4

439 by HC type, 2D GCMS

3

3.5

iso-p normal-p cyclo-p olefin aromatic

2.5

2

1.5 0 1000 2000 3000 4000 5000

primary retention time, seconds

Å C8 -- CARBON NUMBER -- C27 Æ

6000


AROM

ATIC

S

CYCL

OPARA

FFIN

S

OLEFI

NS

PARA

FFIN

S

I

……

.E

VY

Variations on 2D-GCMS spectra

FUEL 606 FUEL 444 FUEL 530 FUEL 438 GOOD ISFC GOOD ISFC POOR ISFC POOR ISFC LOW CETANE MID CETANE HIGH CETANE LOW CETANE LOW T50 MID T50 MID T50 HIGH T50

LGH

A

POLAR

T

H

NON-POLAR 7 Managed by UT-Battelle


HCCI engine

• Defined here as fully premixed, dilute combustion with ignition initiated kinetically near top of compression stroke

• Advantages – Potential for more efficient combustion – Low NOx and low smoke – Simple platform for fuels research

• Same chemistry processes occur in low NOx LTC or PCCI engines, but more mixed up in time and space


ORNL HCCI research engine MODIFIED PISTON WITH SPHERICAL

COMBUSTION BOWL

INTAKE AIR HEATER

ATOMIZING INJECTOR

ENGINE

BELT DRIVE

CONSTANT SPEED MOTORING DYNO

30 - 400 Intake Air Temperature (°C) 20Exhaust Valve Closing (CA deg) 499Exhaust Valve Opening (CA deg) 218Intake Valve Closing (CA deg) 710Intake Valve Opening (CA deg)

10.5:1 Compression Ratio 7.0Stroke (cm) 9.7Bore (cm)

517Engine Displacement (cc)


HCCI engine behavior

• A fuel produces ISFC and combustion trade-offs as a function of combustion phasing

• A collection of fuel and engine characteristics determines where optimum occurs

• Hence, the fuel story also depends on the engine story

10 Managed by UT-Battellefor the Department of Energy

Power output and economy

150

160

170

180

190

200

210

220

230

240

250

355 360 365 370 375

MFB50, atdc

ISFC

, gm

/kw

-hr

2.5

3

3.5

4

4.5

5

IMEP

, bar

ISFC

IMEP


Emissions

0

20

40

60

80

100

120

355 360 365 370 375

MFB50, atdc

NO

X pp

m

0

1000

2000

3000

4000

5000

6000

HC

and

CO

ppm

NOX

HC

CO

MFB50, deg.CA

ISFC

, gm

/kw

-hr

Oil sands fuels showed both enginespecific and fuel specific trends

↑ FUEL SPECIFIC

↓ ENGINE SPECIFIC


10.5 gm/min fuel rate

200

220

240

260

280

300

320

340

360

380

400

350 355 360 365 370 375 380

f438 f439 f440 f441 f444 f445 f446 f447 f480 f481 f482 f483 f530 f531 f605 f606 f607

COMBUSTION PHASING, MFB50

TDC

->

ISFC

, gm

/kw

hr

11 Managed by UT-Battellefor the Department of Energy

MFB50, deg.CA

NO

x pp

m

Ability to advance timing limited by NOx,dP/dCA, peak pressure, noise, etc.

NOx at 10.5 gm/min fuel rate

0

50

100

150

200

250

345 350 355 360 365 370 375 380

f438 f439 f440 f441 f444 f445 f446 f447 f480 f481 f482 f483 f530 f531 f605 f606 f607

NO

x, p

pm



MFB50

CO

ppm

f445f446f447f480f481f482f483f530f531f605f606f607bp15

MFB50

HC

ppm

Ability to retard timing limited bymisfire, high CO, high HC, high COV


CO ppm vs. MFB50 at 10.5 gm/min fuel rate

0

500

1000

1500

2000

2500

350 355 360 365 370 375 380

f438 f439 f440 f441 f444

CO

, ppm


HC ppm at 10.5 gm/min fuel rate

0

500

1000

1500

2000

2500

3000

3500

4000

4500

345 350 355 360 365 370 375 380

f438 f439 f440 f441 f444 f445 f446 f447 f480 f481 f482 f483 f530 f531 f605 f606 f607 bp15

HC

, ppm


Best achievable ISFC shows correlation to cetane and T50

45 50 55 60 65

Best ISFC vs. T50 R2 = 0.658

220

240

260

280

300

320

340

180 200 220 240 260 280 300 320 340

T50 distillation temperature, deg.C

best ISFC vs. cetane

R2 = 0.6142

220

240

260

280

300

320

340

30 35 40

best

ISFC

best

ISFC

cetane number

But, don’t forget that in real fuels,

cetane and T50 also correlate to energy content

and % aromatics and % heavy aromatics and

density and other chemistries and etc.


0180

tem

pera

ture

, deg

.K

Higher cetane fuels show easier ignition,more low temperature heat release

calculated in-cylinder temperature histories

500

1000

1500

2000

2500

225 270 315 360 405 450 495 540

CA degree

530-60.2 446-52.9 439-35.5

Lower starting temperature required for

higher cetane

Main combustion

starts at ~ same temp. for all

fuels

LTHR boosts temperature for

high cetane fuels up to 100 K

332 1782140.716060.2 319 8641935.720452.9 279 4637532.925035.5

ISFC gm/kwhrCO ppmNOx ppm A/F INTAKE

deg.CCETANE

AT CONSTANT MFB50 = ~ 360 deg.CA

CYL

IND

ER T

EMPE

RA

TUR

E, d

eg.K

TDC 15 Managed by UT-Battelle


Summary

• Fuel characterization can be carried down to detailed molecular level

• Lower cetane and lower T50 provided better performance in our engine, with these fuels

• Higher cetane promotes easier ignition, more low temperature heat release

• Trends uncovered are similar to those uncovered with conventional diesel fuels

• Detailed chemistry effects still to be analyzed for


Now what?

• Collaboration is continuing – NCUT, CANMET, PNNL, ORNL, Royal Dutch Shell – Add other companies, labs, universities

• Resolve various analytical methods • Deeper dive into performance – beyond cetane and distillation

– Detailed chemistry effects, statistical analysis • Confirm and broaden results

– New set of refinery based fuels and intermediates – Doping with surrogate compounds (if appropriate) – Extend to oil shale, FT, biodiesel

• Provide information which could be used to support refinery process development or fuel specification decisions


Documents

Response of Oil Sands Derived Fuels in Diesel HCCI Operation · 2014-03-10 · Response of Oil Sands Derived Fuels in Diesel HCCI Operation ... A fuel produces ISFC and combustion