prashant r daggolu sÜd chemie india pvt. ltd. (a ... norms for two/three wheeler after treatment...

BS-VI Norms for Two/Three Wheeler

After treatment approach

Prashant R Daggolu

SÜD CHEMIE INDIA PVT. LTD.

(A CLARIANT Group Company)

SÜD CHEMIE is now a CLARIANT group Co.

CLARIANT ,A globally leading company in specialty chemicals

CLARIANT focuses on creating

value through innovation and

sustainability.

Corporate Center, Pratteln, Switzerland

SCIL/CONFIDENTIAL/ECMA 2016

Contents

• 2W Segment

– Market

– Impact of BSVI Norms

– Expected After treatment System

– Challenges and Approach

– OBD-II

• 3W Segment

– Similar sub sections as above


• High Volumes

• Smaller Engines (move to performance and

sporty bikes)

• High Fuel efficiency conscious

• Lean tuned vehicles

• Low speed driving

• Move to electronic based systems

Indian 2W Market


BS-VI Norms for 2W

Vehicle Class CO,

g/km

THC,

g/km

NOx,

g/km

NMHC,

g/km

THC

(NMHC) +

NOx,

g/km*

PM, g/km EVAP

g/test

Durability

(km)

All Classes 1.0 0.10 0.06 0.068 0.16

(0.128)

0.0045** 1.50 35K

DF 1.3 1.3 1.3 1.3 1.3

BS-VI (with DF) 0.77 0.077 0.046 0.052 0.123

(0.098)

BS-IV (inbuilt

DF); class 2.1

1.403 - 0.39 - 0.79*** - 2/6

Reduction, % 45 - 88 - 84 (89) -

OBD-II 1.9 -- 0.3 0.25 0.05

*Does not have norms – only for evaluation**For GDI engines only*** This is for evap norm of 2 g/test. If evap norm of 6 g/test is chosen; then THC +NOx norm shall be 0.59 g/km

In general, about 90% of Engine out THC emissions of 2W are NMHC; Hence

NMHC limit more applicable – making it more stringent


WMTC-Class 1 & 2.1 Carburetor

0

50

100

150

200

250

300

350

400

450

-1600 -1400 -1200 -1000 -800 -600 -400 -200 0 200 400 600

NO

x, m

g/k

m

, CO mg/km THC mg/km

73%

80%

72%

92%BS-VI

Typical Raw Emissions, g/km24%92%

BS-IV

BS-VI, DF-V1

0.40

2.60 0.65

Current

Performance


WMTC-Class 2.2

0

50

100

150

200

250

300

350

400

-2200 -2000 -1800 -1600 -1400 -1200 -1000 -800 -600 -400 -200 0 200 400 600

NO

x, m

g/k

m

' CO mg/km THC, mg/km

89%96% 0.92

BS-IV

BS-VI,DF-V1BS-VI

2.300.39

74%

86%77%

78%

Typical Raw Emissions, g/km

Current

Performance


WMTC-Class 3.2

0

50

100

150

200

250

300

350

400

-2200 -2000 -1800 -1600 -1400 -1200 -1000 -800 -600 -400 -200 0 200 400 600

NO

x, m

g/k

m

' CO mg/km THC, mg/km

96%97%1.07

BS-VI,DF-V1

2.93

0.44

89%

88%82%

79%

BS-VI

Typical Raw Emissions, g/km

Current

Performance


Effect of A/F on Engine out emission and Catalyst

conversion Efficiency

NOx

HC

CO

A/F Ratio window for 80% catalyst

efficiency at 400 C


Close Loop System and Catalyst Efficiency

Performance of TWC Catalyst is improved with Fuel Metering Control –

Narrower the lambda band the better


Challenges and Approach

Separate Norm for HC and NOx

Separate NOx limit may lead to a reduction in fuel efficiency

Stringent NMHC norm has been introduced

Tighter Engineering Targets

Challenges in implementing OBD-II

Single cylinder Engine – non uniform exhaust flow

Fast reaction times (FI and actuators) –High RPM

Cost sensitive Market


Catalysts for BS-VI Emission Norms

• High activity and selectivity

• Low LOT

• High thermal stability

• High OSC

• Optimum PGM density and ratio

• Judicious utilization of PGM

• PGM Dispersion

• 2 Catalysts required for thermal management

• Available on structured substrates

• NOx is space velocity sensitive: larger and higher cpsi substrate• Wash coat chemistry

• PM support interaction

• Oxygen Storage materials (OSC)

• Wash coating technology• Segregated : to minimize potential alloying

• Layered / Zone

• Wash coat Properties and Rheology


All Classes

• EFI with Closed-loop (Stoichiometric A/F) control

• May need SAI if engine has to run rich for combustion stability and/or performance

• Three Way catalyst(s)

TWC-1 TWC-2

SAI

O2

Sens.ECU


Typical Reactions on TWC Surface

HC + O2 CO2 + H2O

NO + CO CO2 + 0.5N2

NO + H2 0.5N2 + H2ONO + HC CO2 + H2O + 0.5N2

CO + 0.5O2 CO2

CO + H2O CO2 + H2

Reduction

Oxidation


Scheme 1

Typical Layering / Zone Coating Technology

Every layer is :

Optimized for metal support interactions / devoid of negative

interactions

Improved utilization of Rh & durability

Specifically targeted to individually abate HC and NOx

Top Layer – NOx Reduction

Bottom Layer – Oxidation Catalyst

Scheme 2

Lower light-off temperature and better cold start conversion

Control of emissions at high speed / high temperature

Improved conversions of CO, HC & NOx

PGM loading can be lowered


Washcoat/PGM Dispersion

High Dispersion catalysts important for better PGM utilization


OBD -2W

Monitoring Items OBD-I (1st

April, 2020)OBD-II (1

st

April 2023)

Circuit continuity for all emission related powertrain

component (if equipped

Distance Travelled since MIL (malfunction indicator

lamp) ON

Electrical disconnection of Electronic Evaporative purge

control device ( if equipped & if active)

Catalytic Converter Monitoring X

EGR system Monitoring

Misfire Detection X

Oxygen Sensor Deterioration X

OBD systems for emission control shall have the capability of

identifying the likely area of malfunction by means of fault codes

stored in the computer memory


Vehicle Class OBD-II Stage

Type CO g/km NMHC g/km NOx g/km PM g/km

Class -1 & 2-1

(BS-VI Norm)1.90

(1.00)

0.250

(0.068)

0.30

(0.060)0.050*

(0.0045)

Class- 2-2

(BS-VI Norm)1.90

(1.00)

0.250

(0.068)

0.30

(0.060)0.050*

(0.0045)

Class - 3-1 & 3-2

(BS-VI Norm)1.90

(1.00)

0.250

(0.068)

0.30

(0.060)0.050*

(0.0045)

OBD-II Emission thresholds for BS-VI

* GDI Vehicles only


3W - Diesel


• Low cost market

• Small Engines, low speeds

• Space constraints

• Most cost effective AFT solution expected

• Major Urban short distance transportation system –

high volumes

• Can carry 3-5 persons or light freight

• Largely run on Diesel – but some on CNG, LPG and

Gasoline

3W Market info - India


All norms with DF3 Wheeler – Diesel Norms

HC+ NOx, mg/kmCO, mg/km

0

5

10

15

20

25

30

35

40

-400 -300 -200 -100 0 100 200 300 400 500

PM

, m

g/k

m

-42% -32%

-41%

345 380

35

21

200 260

BS-4

BS-6

HC NOx

100 160

HC and NOx separated in BS VI

NOx Limit relaxed from 100

mg/km to 160 mg/km


Advance Engine

NOx

PM

Stringent

Norms

SCR

Part

icu

late

Filte

r

Current Engine

Current Limit (BS-3)

NOx-PM Trade Off

NOx PM Trade off – One has to be

controlled at the expense of the otherSCIL/CONFIDENTIAL/ECMA 2016

HC, CO, Particulate matter (PM)

DOC + DPF System – Overview

• DOC:

– Must have low Light Off performance for HC and CO conversion

– Needs resistance & robust stability against thermal deactivation.

• DPF:

– High filtration efficiency reqd for efficient soot trapping .

– Additional CO/HC Clean up functionality a must to avoid secondary emissions during regeneration.

– High stability against thermal degradation is mandatory for meeting durability /life in field .

DPFDOC

Challenges


DPF

HC, CO

NOxNO NO2

Supports DOC Function

Minimizes NO2

Particulate MatterSupports Soot Burning

via NO2

Functions of DOC and Diesel Particulate Filter

DOC

DOC + DPF System - Mechanism


SCIL NO2 make Catalyst

EnviCat® DOC: Different PGM Loadings

Increasing

PGM


NOx control Strategies – LNT & SCR

• NOx control is difficult for Lean tuned Engine

(Diesel)

• LNT: Also called NSC, stores NOx and reduces

during a rich pulse

• SCR: NOx may be reduced by adding an

additional Reactant (NH3)


LNT (NSC)

• Lean NOx Trap/ NOx

Storage Catalyst

• At low temperature will store

NOx and release at High

temperature/ Rich Pulse

• Reduction happens during

the High Temperature pulse

NO

x S

tora

ge

/Co

nve

rsio

n

Temp

SCR

LNT


Selective Catalytic Reduction


DPF Regeneration Strategies

• Active regeneration

requires system

changes

• HC pulses via engine

or into exhaust line is

needed

• Electric burners or fuel

additives maybe

available

• The objective is to burn

soot with air

Source: BOSCH


Condition: NOx controlled from

Engine

– Electronic Fuel Injection

– Calibrate for low NOx (EGR)

– Closed Coupled DOC+cDPF

– DOC for oxidation of CO/HC

and NO2 make for passive

soot oxidation

– Pressure sensor for OBD-II

monitoring and signaling to

ECU for late cylinder injection

for active cDPF regeneration

when needed

– Less penalty on fuel for active

regeneration

DOC cDPF

ECU

Pressure Sensor

Option 1: DOC + cDPF

NOx Limit relaxed from 100

mg/km to 160 mg/km


Option 2: DOC + cDPF + LNTCondition: NOx reduction

requirement of <70%

• LNT Approach

– Control NOx through LNT

– Rich pulse needed for

Regeneration

– High PGM loaded

catalyst

• The role of DOC and cDPF

shall be as before

• Active Regeneration

DOC cDPF LNT

ECU

Pressure Sensor


Option 3: DOC + cDPF +SCR

Condition: NOx reduction

requirement of >70%

• SCR Approach

– Control NOx through SCR

– Maximum > 90%

conversion possible

• The role of DOC and cDPF

shall be as before

DOC

AdBlue

cDPF SCR


SCR Vs LNT for NOx Conversion

• SCR

– Conversion: >90%

– Non PGM catalyst

– Can be tuned for various

operating conditions

– Needs several accessories

- Adblue Tank

- Pump

- Mixer

- NH3 slip measurement

- Ammonia Slip catalyst

– Space Constraints

• LNT/NSC

– Conversion: 70% max

– High PGM Loadings

– Best operating temperature

of 200 – 450 C

– No Accessories needed

– Rich Pulses needed for

regeneration- ECU programed

Source: BoschSCIL/CONFIDENTIAL/ECMA 2016

3W Reductions - Solutions

CO HC NOx PM

Baseline, g/km

(No EGR)

0.4 0.1 0.6 0.350

BS-VI norm 0.2 0.1 0.16 0.021

Conversion

needed

To meet norm

with DF, %

50 0 72% 95%

With EGR, NOx could be brought down by ~50%, 43% further NOx reduction

Needed


Decision Matrix

ENGINE

OUT NOX

WITHIN

LIMIT

DOC +cDPF

REQD

NOX

CONV

<70%

Yes

PM

WITHIN

LIMIT?DOC +LNT

REQD

PM

CONV

<50%

DOC +PFF +LNT

PM

WITHIN

LIMIT?

REQD

PM

CONV

<50%

Yes Yes

Yes

DOC+SCR

DOC+PFF+SCR

Yes

DOC+cDPF+SCR DOC+cDPF+LNT

No

No

No No

No No

Yes

Final AFT system configuration depends on Engine out emissions


Challenges – Single cylinder & Two Cylinder NA engine More than 70% of operating points are at full load and peak temperature for an NA single cylinder/Two cylinder engine

is ~ 520 °C at an air excess ratio of ~ 1.4; Minimum temperature required regenerating soot in DPF is ~ 600 °C. Throttling of NA engine for temperature rise will result in significant reduction of air flow and significant increase in soot

emission.

SPEED [RPM]

1000 1500 2000 2500 3000 3500 4000

To

rq

ue

[N

m]

2.5

5.0

7.5

10.0

12.5

15.0

17.5

20.0

22.5

25.0

27.5

30.0

32.5

35.0

37.5

40.0

42.5

1.5 1.5

1.5

1.81.8

1.8

2.0 2.0

2.02.3 2.3

2.32.5 2.5

2.52.8

2.8

2.83.0

3.0

3.03.33.3

3.33.5 3.53.53.8 3.83.84.0 4.04.04.5 4.54.55.0

2.0

1.5

1.4

1.31.31.31.41.3

TO

RQ

UE

[N

m]

2.5

5.0

7.5

10.0

12.5

15.0

17.5

20.0

22.5

25.0

27.5

30.0

32.5

35.0

37.5

40.0

42.5

200

250

300

350

400

450

500

Operating points – real world

Exhaust temperature isolines

Air excess ratio isolines

SOURCE: SIAM


• DOC+cDPF+LNT/SCR

• DOC coated with Pt-Pd based WC

• cDPF with Pt-Pd based WC with moderate PGM

• Both DOC and cDPF to withstand high

exotherms

• LNT with high PGM loading

Catalytic Systems


• EnviCat® DOC

• EnviCat® cDPF (Passive Regeneration)

• EnviCat® Catburner (Active Regeneration)

• EnviCat® SCR (VWT)

• EnviCat® Clean up Catalyst

• EnviCat® Hydrolysis Catalyst

• EnviCat® SCR (Zeolite)

• EnviCat® LNT

Sud Chemie Product Portfolio


Facilities @SCIL


• 2W

– Move to TWC

– EFI closed loop control

– SAI may be needed (in specific cases)

• 3W

– DOC + cDPF with Active Regen needed

– LNT/SCR may play a role on at least in higher inertia vehicles

– Cost implications have to be studied

• Engine out emissions on BSVI Engines will determine AFT system

strategy

• SCIL offers all product ranges

Conclusion


THANK YOU FOR YOUR ATTENTION!!


Meeting BS-VI With CARB Engines

• Tune engine richer to minimize NOx

• Use special reduction catalyst, primarily Rh, to reduce NOx

• Add SAI after reduction catalyst

• Use oxidation catalyst to primarily convert remaining CO and HC

• Issues:

– Need secondary air injection into muffler

– Need SAI port and piping

– Requires two catalysts – higher cost

RED

CAT

OXY

CAT

SAI

CARB


OBD - 3W

Monitoring Items OBD-I (1st

April 2020)OBD-II (1

st

April 2023)

Circuit continuity for all emission related powertrain

component (if equipped

Distance Travelled since MIL (malfunction indicator

lamp) ON

Electrical disconnection of Electronic Evaporative purge

control device ( if equipped & if active)

Catalytic Converter Monitoring X

EGR system Monitoring X

Misfire Detection X

Oxygen Sensor Deterioration X

OBD systems for emission control shall

have the capability of identifying the

likely area of malfunction by means of

fault codes stored in the computer

memory

OBD II Limit, mg/km

CO 440

NOx 300


prashant r daggolu sÜd chemie india pvt. ltd. (a ... norms for two/three wheeler after treatment...

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