EXPERIENCES ABOUT NO 2

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Transcription:

EXPERIENCES ABOUT NO 2 J. Czerwinski, AFHB A. Mayer, TTM MVEG Meeting Brussels, 19. Nov. 212

EXPERIENCES OF VERT: CDPF S & DIFFERENT MEASURING SYSTEMS SAE 27-1-321

Liebherr engine at the test stand DPF DI TC 6.11 dm 3 2 rpm 15 kw Dilut. tunnel silencer

TFULNESSUA ROTASYLAN -Ax ON x ON S IS EH S IL -F LE -G A IK RET IL 2 ON ON REYRD N IOFAN SAGBA IN E RET IL FBUATS IN E TFULLÜP (S TFULNESSUA ) EPMUPKCURDRETNU ON 2 ON x ON IT EH IN ESSEMSAGBA AMBIENT AIR NOx - ANALYZER HOT SILICA-GEL- FILTER NAFION DRYER EXHAUST GAS INLET DUST FILTER VAACUM PUMP SCAVENGING AIR INLET M SCAVENGING AIR OUTLET SUA TFULLÜPS ESUÄHEG GNULEGER DNU IGEZNARUTAREPMET NE 7 HOUSING TEMPERATURE READING & REGULATION HEATING GNUIZ EH HEATED LINE ET IZ EHEB GNUIT EL NO X measuring systems: hot analyzer with heated line and Nafion Gas Sample Dryer and cold analyzer TEMP. REGULATION HEATED LINE IZ EHEB GNUIT EL ET GNULEGERRUTAREPMET HEATED PREFILTER RET IL F RET IZ EHEBROV COOLER REPRÖKLHÜK H2O SEPARATOR 2 WITH FILTER 2 M IT ZTAS IN ERET IL F EHCSBA ID SSÄFEGE H2O SEPARATOR 1 SSÄFEGE ID EHCSBA 1 COOLER RELHÜK NOx - ANALYSAZER TLAK ROTASYLAN -Ax ON COLD SUA SAGBA EXHAUST GAS OUTLET

HEATED SAMPLING SYSTEM EN 14792 p.25 1. exhaust chanel 2. heated filter 6. analyzer 1. calibration gases 11. heated zone 12. sample conduit 13. by-pass 14. gas divider 15. pump

[ % ] 645 865 NO X [ppm] 115 118 1322 144 155 188 26 227 25 2 hot measurement cold measurement CRT NO X 15 1 Comparison of NO X - values during the cold and hot measurement 5 1 Liebherr 914T, LSD (S<5ppm) 8 NO X / NO Xcold 82.9 6 4 32.9 33.9 2 17.2 1.2 2rpm full load 2 rpm 378Nm 14rpm full load 14rpm 445Nm 14rpm 297Nm

[ % ] NO 2 [ppm] 9 8 7 hot measurement cold measurement CRT 68 78 6 NO 2 5 4 3 29 41 3 Comparison of NO 2 - values during the cold and hot measurement 2 1 52 51 9 73 63 Liebherr 914T, LSD (S<5ppm) 12 1138 1 8 NO 2 / NO 2cold 74 832 6 458 4 2 233 2rpm full load 2 rpm 378Nm 14rpm full load 14rpm 445Nm 14rpm 297Nm

[ % ] Increase of the NO X concentration with hot measuring system relatively to the cold measurement Ammann particle trap (preconditioned with Pt/Ce) & CRT particle trap 1 8 6 Ammann K2 - particle filter CRT - particle filter Strong catalytic activity 4 average 26.89 % 2 2rpm full load 2rpm 378Nm 14rpm full load 14rpm 445Nm 14rpm 297Nm

[ % ] Increase of the NO X concentration with hot measuring system relatively to the cold measurement IBIDEN-, Greentop-, INTECO Particle trap & LUBRIZOL water-emulsion 12 1 8 weak catalytic activity IBIDEN A-1 DPF + FBC IBIDEN B-1 DPF + FBC INTECO DPF + FBC GREENTOP DPF + FBC LUBRIZOL emulsion w/o DPF 6 4 average 2.87 % 2-2 -4 2rpm full load 2rpm 378Nm 14rpm full load 14rpm 445Nm 14rpm 297Nm -6

Increase of the NO X concentration measured hot with Nafion Dryer relatively to the hot measurement without Nafion Dryer 1 [ % ] Ammann K2 - particle filter & additive Pt/Ce IBIDEN A-1- particle filter & additive Octimax 8 6 average 5.29 % 4 2 2rpm full load 2rpm 378Nm 14rpm full load 14rpm 445Nm 14rpm 297Nm

7 19 22 47 NO 2 [ppm] 19 15 28 34 37 74 362 28 543 39 NO [ppm] 188 11 117 1867 177 22 384 NO X [ppm] 65 59 195 12 132 113 1886 211 23 25 2 NO X 15 1 5 25 2 NO Horiba-CLA-51, cold CLD 7 EL ht, hot line Comparison of NO X / NO / NO 2 values during measurements cold, hot, hot + Nafion Dryer 15 1 5 CLD 7 EL ht, hot line / Nafion Dryer with CRT(2), Liebherr 914T, LSD (S<5ppm) 8 7 6 NO 2 5 4 3 2 1 2rpm 57Nm 14rpm 62Nm 2rpm 252Nm 14rpm 297Nm

NO 2 /NO X [%] Effects of different aftertreatment devises on NO 2 -portion in exhaust gas engine Liebherr 914 T, 14rpm, ULSD Diesel S<1ppm FBC Octel Octimax 481a 1.8x (29ppm Fe/ 7ppm Sr) 6 5 all with FBC 4 CRT 3 2 1 Airmex Ox.Cat. w/o DPF 1 2 3 4 5 Température T5 [ C ]

NO 2 /NO X [%] Influence of FBC on NO 2 -ratio with/without CRT engine Liebherr 914 T, 14rpm, ULSD Diesel S<1ppm FBC Octel Octimax 481a 1.8x (29ppm Fe/ 7ppm Sr) 7 6 5 CRT w/o FBC 4 3 CRT with FBC 2 1 w/o DPF with FBC w/o DPF w/o FBC 1 2 3 4 5 temperature T5 (before trap) [ C ]

w/o FBC with FBC average NO2 [ppm] with DPF Airmeex w/o FBC with FBC with ox.cat. Average NO 2 concentrations in 1 operating points with different configurations DPF/FBC engine Liebherr 914 T, 14rpm, ULSD Diesel S<1ppm FBC Octel Octimax 481a 1.8x (29ppm Fe/ 7ppm Sr) 5 45 4 CRT 35 3 25 2 15 w/o DPF with FBC 1 5

NO 2 / NO X [%] 7% Pt-Coating A 6% Pt-Coating B 5% 4% 3% w/o DPF Pt-Coating C Pt-Coating D Pt-Coating E NO 2 /NO X ratio with different DPF's & coatings in the VERT verification tests. Pt-Coating F 2% 1% Base-Metal Coating G Base-Metal Coating H + Fe-FBC % 1 2 3 4 5 T5 (before DPF) [ C]

Conclusions (1) Strong catalyst Hot measurement + 27 % NO X Nafion Dryer + 5 % NO X NO 2 /NO X maximum at 3 C - 35 C

Conclusions (2) FBC at short term no effect on NO 2 /NO X at long term with Pt strong effect Absolute NO 2 -values depend on: engine out emissions & temp. position & temp. of DOC (Ox.Cat)

CONDITIONS OF NO 2 -FORMATION SAE 213

Test Engines

IVECO ENGINE F1C IN THE ENGINE ROOM Manufacturer Iveco, Torino Italy Type F1C Euro 4 Displacement RPM Rated power Model Combustion process Injection system Supercharging 3. Liters max. 42 rpm 15 [kw] @ 35 [min -1 ] 4 cylinder in-line direct injection Bosch Common Rail (CR) 16 bar Turbocharger with intercooling Emission control Development period cooled EGR until 25

LIEBHERR ENGINE D934 IN THE ENGINE ROOM Manufacturer Liebherr Machines Bulle S.A., Bulle/Fribourg Type D934 S Displacement 6.36 Liters RPM 2 min -1 Rated power Model Combustion process Injection system 111 kw 4 cylinder in-line direct injection Bosch unit pumps Supercharging Emission control Turbocharger with intercooling none (exhaust gas aftertreatment according to the requirements) Development period 25

Tested DPF Systems

DPF Syst. Nbr. DOC DPF Pt [g] Pd [g] Pt [g] regeneration active volume [feet 3 ] summary Pt [g] Passive regeneration 1 8.33 4.16 1.45 SiC ø 144mm x 12mm SiC ø 144mm x 254mm CRT.2 9.78 5.58 1.39 1.45 2 SiC ø 144mm x 12mm SiC ø 144mm x 254mm CRT.2 7.3 1.16 1.16 1.45 3 SiC ø 144mm x 12mm SiC ø 144mm x 254mm CRT.2 2.61 8.33 4.16 4 SiC ø 144mm x 12mm SiC ø 144mm x 254mm CRT.6 8.33 2.94 1.47 4.41 5 SiC ø 229mm x 152mm SiC ø 229mm x 35mm CRT.66 7.35 4.41 4.41 4.41 6 7 SiC ø 229mm x 152mm - SiC ø 229mm x 35mm 4.41 SiC ø 229mm x 35mm CRT cdpf.66.44 8.82 4.41 4.41 4.41-8 9 1 SiC ø 229mm x 152mm Pt/Pd/Rh Metal ø 283.5mm x 13mm - SiC ø 229mm x 35mm Pt/Pd/Rh SiC ø 283.5mm x 355mm V 2 O 5 SiC ø 275mm x 584mm CRT CRT cdpf.22.81 1.22 4.41 n/a - 3.8 - V 2 O 5 (14g/L) 11 SiC SiC CRT.24 3.8 ø 151mm x 12mm ø 151mm x 3mm DATA OF THE TESTED DPF SYSTEMS Semi active regeneration 12 3 3 - Cordierite ø19mm x 152mm SiC ø 21mm x 23mm fuel aero-sol gene-rator + DOC.35 3

Results

NO2 [ppm] temperature t7 [ C] NO2 [ppm] tem 18 3 24 18 DPF1 Pt 9.8g DPF2 Pt 7g DPF3 Pt 2.6g DPF4 Pt 8.3g DPF3 Pt 2.6g DPF4 Pt 8.3g NO 2 -PRODUCTION IN STEP-TEST WITH DIFFERENT CONTENT OF PT IN THE CATALYTIC COATING, SMALLER DPF S, IVECO ENGINE F1C 12 6 6 12 18 24 time [s] 42 6 NO 2 /NOx [%] 36 3 24 18 3 24 18 DPF1 Pt 9.8g DPF2 Pt 7g DPF3 Pt 2.6g DPF4 Pt 8.3g DPF1 Pt 9.8g DPF2 Pt 7g DPF3 Pt 2.6g DPF4 Pt 8.3g 4 2 5 Nm 1 Nm 15 Nm 2 Nm Reference w/o DOC & DPF DPF1 Pt 9.8g 12 6 DPF2 Pt 7g DPF3 Pt 2.6g DPF4 Pt 8.3g 6 12 18 24 time [s] 6 NO2 /NOx [%] 4

3 24 18 reference w/o DOC & cdpf DPF5 Pt 7.4g DPF6 Pt 8.8g FTIR 12 NO2 [ppm] 6 8 6 4 2 8 6 NO2/NOx [%] ΔNO2/NOx with DOC & cdpf [-] FTIR FTIR NO 2 & NO 2 VERSUS TEMPERATURE WITH DIFFERENT PT- CONTENT AND DIFFERENT ACTIVE VOLUME OF THE BIGGER DPF S, IVECO F1C 4 2-2 -4 DPF7 Pt 4.4g DPF8 Pt 4.4g 15 2 25 3 35 4 45 5 Temperature b. DOC & cdpf [ C] > NO 2 = NO 2with DOC & cdpf - NO 2without DOC & cdpf > NO 2 /NOx with DOC & cdpf > average values, 6 s

NOX, NO & NO 2 IN ETC WITH DIFFERENT PT-CONTENT, SMALLER DPF S, IVECO F1C CLD 1 1 1 1 1 8 8 8 8 8 6 6 6 6 6 4 4 4 4 4 2 2 2 2 2 NOx [g/test] NO [g/test]* NO2 [g/test] NO2/NOx [%]** ΔNO2/NOx [%] REF DPF1 Pt 9.8g DPF2 Pt 7.g DPF3 Pt 2.6g DPF4 Pt 8.3g * mass of NOx and NO calculated with density of NO 2 ** calculated with vol. concentration [ppm] average values

NO X & NO 2 IN ETC WITH DIFFERENT DPF SIZE, IVECO F1C

Ratio DPF9 Ratio DPF1 INFLUENCE OF HIGH SULFUR DIESEL FUEL (HSD) ON THE NO 2 /NO X -RATIO WITH DIFFERENT COATINGS (PT OR V); LIEBHERR D 934S 45 NO2 / NOx ratio 6 3 15 ulsd DPF9 (Pt) hsd DPF1 (V) 4 2 12 24 36 48 6 time [s]

Effect of Sulphur Contents (in ppm S) in Fuel On NO Conversion over CRT-Catalyst Johnson Matthey SAE 22-1-1271

backpressure [mbar] NO2 [ppm] engine torque [Nm] temperature [ C] EFFECT OF DIFFERENT SOOT LOADING HISTORY ON NO 2 -EMMISSIONS DURING THE REGENERATION PROCEDURE, DPF11; LIEBHERR D 934S 7 6 5 4 3 2 1 2 16 Regeneration n = 11 rpm p 7 M load steps reg. nr. 3 preliminary / reg. nr. 1 unloaded / reg. nr. 2 defined / reg. nr. 3 reg. nr. 1 6 5 4 3 2 1 5 4 Regeneration n = 11 rpm t 7 before DPF FTIR reg. nr. 2 reg. nr. 3 reg. nr. 2 load steps reg. nr. 1 12 8 reg. nr. 2 reg. nr. 3 3 2 reg. nr. 3 reg. nr. 1 4 1 NO 2 6 12 18 24 3 36 42 48 54 6 time [s] 6 12 18 24 3 36 42 48 54 6 time [s]

backpresssure [mbar] NO2 [ppm] engine torque [Nm] temperature [ C] IMPACT OF BIO-FUELS (RME) ON REGENERATION AND NO 2 -EMMISSIONS, DPF11; LIEBHERR D 934S 7 6 5 4 3 2 1 22 17 Regeneration n = 11 rpm B2 M load steps reg. B2 reg. B reg. B2 reg. B1 6 48 36 24 12 28 24 2 Regeneration n = 11 rpm CLD t 7 before DPF B2 B load steps B1 B1 12 7 2 B B1 6 12 18 24 3 36 42 48 54 6 time [s] p 7 16 12 8 4 B NO 2 B2 6 12 18 24 3 36 42 48 54 6 time [s]

CONCLUSIONS (1) with presence of Pt-coating in DOC, in DPF, or in both, there is an oxidation NO-NO 2 and a typical maximum of the NO 2 /NO x -ratio in the temperature range around 35 C, with higher Pt-content in the coatings, there is a higher potential of NO 2 -formation (larger temperature range and higher maximum values), in the low-temperature range (low-load engine operation) the catalysts are below the light-off temperature and the DPF s reduce slightly NO 2 ; the absolute values of NO 2 & NO x are low in these operating conditions and the NO 2 /NO x - ratio gives an exagerated picture of the NO 2 -differences, the bigger size, or bigger active volume of the aftertreatment system causes a lower spatial velocity, longer residence times and a more intense NO 2 -production,

CONCLUSIONS (2) the higher sulfur content in fuel inhibits the NO NO 2 oxidation and gives preference to the SO SO 2 oxidation; the Vanadium-based coatings have potential of lowering NO 2, with used and/or soot-loaded DPF (DOC) there is less production of NO 2 ; the reasons are: masking, or ageing of the catalytic coating and use of NO 2 for soot oxidation, with high portion of RME in fuel (or pure RME) higher NO 2 emissions can occur; the reasons for that are: higher engineout NO x -emissions, higher reactivity of RME-post products, lower exhaust temperatures and higher probability of exhaust temperature near to the range of maximum NO 2 - production, during, or after some active, or semi active regeneration procedures of catalytic DPF-systems, temperatures of maximum NO 2 -formation are attained.

with SCR

Comparison of different Systems in Steps-Test at 22 rpm: Reference - PF1(cat.)+SCR - PF3(FBC)+SCR, 6s Average Values of stationary Operating Points

Correlations 2 CLD-FTIR

NO x NO CORRELATIONS 2CLD-FTIR NO 2

GENERAL CONCLUSIONS NO 2 is a secondary emission NO 2 increases the opacity NO 2 causes the nuisance of smell NO 2 increases the toxicity NO 2 is produced with noble metal catalysts For limitation of NO 2 the measuring systems should be more strictly defined There are technical measures to reduce NO 2