diesel particulate matter control strategies in the mining ...€¦ · turbo boost press intake...

Diesel Particulate Matter

Control Strategies in the

Mining Industry

Dr Brian Davies AM

© 2018 – Dr B Davies AM

What is DPM & Why Control It?

• Small particles (15-30 nm) called spherules

• Agglomerate to form larger particles (<1 m in diameter)

• Absorb significant quantities of hydrocarbons and other organic compounds

• Have traces of inorganic compounds

• Respirable

• Significant component of diesel exhaust emissions which was declared carcinogenic to humans by IARC in 2012

2


Diesel Particulate - Composition

Electron micrograph –

mine diesel particulates

showing spherules,

chains and agglomerates

Schematic – mine diesel particulate

showing spherules, chains and

agglomerates

Source: A Rogers

3


What Control Technologies are Available?

• Low emission fuel

• Low emission engines

• Ventilation

• Exhaust filtration systems (DPFs & DDEFs)

• Air conditioned & filtered operator cabins

• Operating practices

• Driver & workforce education

• Personal protective equipment

• Emissions based maintenance

• Nuclear option – use of alternate powered equipment4


What is Emissions Based Maintenance?

• Maintenance of an engine in ADDITION to OEM & statutory requirements to reduce exhaust emissions

• An effective control at the source of exhaust emissions to reduce workplace DPM and gas exposures

• Not a new control, under-utilised, requires management support and collaboration across an organisation

• An engine can only be as good as the maintenance it receives

5


EBM as a Control

• Links health outcomes with productivity gains

• Critical (or priority) control

– Reduces emissions at the source ✓

– Reduces exposure to workers ✓

– Reduces amount of fuel used ✓

– Vehicles have less breakdowns (improved reliability) ✓

6


History of EBM

• US Bureau of Mines

• DEEP – Canada

• Canyon Fuel Company - USA

• Tower Colliery – Australia

• Metalliferous industry – USA, Canada, Mongolia & Australia

• Coal industry – Australia (NSW Department of Industry: EBM component

of Mechanical Engineering Control Plan)

7


Same Engine Over Time

Why are results lower on these two tests?

8


Different Engines But Same Type & Approximate Age

1 2 3 4 5 6 7

9


How does it work?

• Testing of engine gaseous and particulate emissions on a regular basis plus additional testing if maintenance conducted – Stage 1

• Test prior to and after exhaust controls (catalytic converters, diesel particulate filters) – Stage 1

• Develop target values & interpret results – Stage 2

• Act on results to maintain the engine in a cleaner and more efficient manner – Stage 3

Stage 1 Stage 2 Stage 3

10


Raw Exhaust Testing Equipment

Equipment must be suitable for use by site personnel

Source: J Hines

11


Intake Restriction & Backpressure Measurement

Source: S McGinn


How & where to collect a valid sample

• Sample collection point needs to be pre & post control technologies to identify engine faults AND measure efficiency of controls

• Using tail pipe data only leads to significant errors in interpretation and inability to identify maintenance issues

• Sample collection is best done using a mixing device & water trap (mandatory after a water based exhaust conditioner for spark suppression)

13


• Probe insertion distance• Variability of exhaust flow• Temperature• Sampling point (manifold vs

tailpipe)• High moisture content in

exhaust

Issues when sampling Diesel Particulate

Proven approach: Water trap and exhaust mixing system

14

Source: B Davies


Source: Jeanot Tourneur

Exhaust Velocity from MT6020

15


Sampling Points

16

Source: B Davies


Maintenance Personnel Performing a Gas Test

17

Source: B Davies


Loading Engines for EBM Testing

Source: M W Spears

Video on loading engines

https://e-r-p.com.au/diesel-exhaust-monitoring/training-tools/

Source: ERP Engineering Pty Ltd

18

Target load point

https://e-r-p.com.au/diesel-exhaust-monitoring/training-tools/


• Transient (20sec idle-20sec load-20sec decay to idle) –suitable for any vehicle that can be loaded via a torque converter or hydraulics

• Snap test – 8sec idle to flight revs snaps (60sec max) –suitable for manual gear box engines such at 4WD light vehicles

Always allow engine transmission to cool before commencing gas test

Loading Engines - DPM

19


DPM Test Procedure

Source: MDG 29 2008

20


Loading Engines - Gases• 60sec steady state load with 10 second pre – load

(torque converter or hydraulics)• Some OEMs will only warranty up to 30 sec load:

can be overcome by using the “dwell” time of the sampling line on the gas analyser

• Determine maximum RPM & apply load to decrease RPM by 10% (for example if max RPM is 2200rpm apply load to reduce to 2000rpm)

• CO2 & O2 between 6-12% indicates acceptable load on engine

21


Gas Test Procedure

0

100

200

300

400

500

600

700

800

900

1000

1 7 13 19 25 31 37 43 49 55 61 67 73 79 85

ppm

Seconds

CO and NO Emissions Chart over 90 Seconds

CO

NO

Source: S McGinn & B Davies

22

10s

20s

60s

Dwell time of analyser

10s


Development of Emission “Target Values”Two methods currently in use:

1) Conformance to baseline analysis

a) Maintain engine to within a % of a baseline analysis when engine new

b) Assumes engine never changes during lifetime

c) Current baseline requirements same as accuracy of DPM instruments making compliance difficult

2) Statistical evaluation of best practice

a) Based on current diesel fleet

b) Takes account of aging fleet as new engines lower target values over time

c) Is international best practice

23


Statistically Based Target Values and Use

• Collect samples for DPM, NO2, NO & CO at each location (manifold & tailpipe) for each engine type

• Collect key engine data e.g. turbo boost, backpressure, intake restriction

• Apply basic statistics – 95% UCL = ‘Initial’ target values

• Fix engines above the 95% UCL, retest and recalculate and fix those above 95% UCL – REPEAT….. until no gain

= In-service target value24


Statistically Based Target Values (QSK 19 -Manifold)

Engine Number

Month 1

EC mg/m3

Month 2

EC mg/m3

Month 3

EC mg/m3

1 28 28 282 26 26 263 29 29 274 33 25 255 33 26 266 29 29 277 27 27 278 35 25 25

a) Average 30 27 26b) STD Deviation 3.3 1.6 1.1c) 95% Confidence 2.3 1.1 0.7

95% UCL = (a + c) 32 28 27

Target Value 32 28 2725


Target Values over Time - Personnel Transport

0

5

10

15

20

25

30

35

40

mg

/m3

Diesel Particulate (EC)

Manifold

Month 1 Month 3

Diesel Particulate (EC)

Tailpipe

Month 1 Month 3

Source: J Hines – Used with permission

26


Recording of Results• If all data is stored it is possible to:

– Compare results from vehicles with same engine type and identify abnormal engines

– Follow emission profile over life of engine and predict when rebuild required

– Follow the efficiency of critical controls (DOC & DDEF) and reduce risk of worker exposure

– Demonstrate compliance to company & statutory requirements

– Demonstrate industry best practice

Data management presents difficulties at the site level

27


Interpretation of ResultsBasic analysis

– High CO – possible fuel issue or intake restriction

– High NO – possible timing issue or ECM may be stuck in “smoke” mode

Detailed analysis

– Requires some key engine parameter data

– Greater chance of quickly identifying issue

– Computer software available to assist28

Hi Idle Trans-Hyd StallTrans Stall

CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1900 1750

150 30

600 600

30 30

12 12

7 7

400 385

RPM

ppm

ppm

ppm

%

%

°C

145

3

41

6

450

°C

KPa

KPa

KPa

KPa

Diesel Oxidation Catalyst

R 1700 Loader

CAT 3176CEngine

Source: S McGinn

29


CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1700 1500

400 100

600 600

30 30

12 12

7 7

450 385

RPM

ppm

ppm

ppm

%

%

°C

110

8

6

450

°C

KPa

KPa

KPa

KPa

41


R 1700 Loader

CAT 3176CEngine

Source: S McGinn30


CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1850 1750

100 200

600 600

30 30

12 12

7 7

400 385

RPM

ppm

ppm

ppm

%

%

°C

140

3

41

10

450

°C

KPa

KPa

KPa

KPa


R 1700 Loader

CAT 3176CEngine

Source: S McGinn31


CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1700 1500

400 100

600 600

30 30

12 12

7 7

400 385

RPM

ppm

ppm

ppm

%

%

°C

85

3

41

6

450

°C

KPa

KPa

KPa

KPa


R 1700 Loader

CAT 3176CEngine

Source: S McGinn

32


CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1850 1750

100 20

1000 1000

50 50

12 12

7 7

400 385

RPM

ppm

ppm

ppm

%

%

°C

140

3

82

5

450

°C

KPa

KPa

KPa

KPa


R 1700 Loader

CAT 3176CEngine

Source: S McGinn

33


CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1700 1500

400 100

600 600

25 25

12 12

7 7

400 385

RPM

ppm

ppm

ppm

%

%

°C

105

3

43

5

240

°C

KPa

KPa

KPa

KPa


R 1700 Loader

CAT 3176CEngine

Source: S McGinn

34


CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1700 1500

400 100

600 600

25 25

12 12

7 7

400 385

RPM

ppm

ppm

ppm

%

%

°C

105

3

43

5

450

°C

KPa

KPa

KPa

KPa


R 1700 Loader

CAT 3176CEngine

Source: S McGinn

35


CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1850 1750

100 100

600 600

25 25

12 12

7 7

400 385

RPM

ppm

ppm

ppm

%

%

°C

140

3

45

10

450

°C

kPa

kPa

kPa

kPa

DPM 15 <1

Diesel Particulate Filter

R 1700 Loader

CAT 3176CEngine

Source: S McGinn

mg/m3 EC

36


CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1850 1750

100 100

600 600

25 25

12 12

7 7

400 385

RPM

ppm

ppm

ppm

%

%

°C

140

3

45

6

450

°C

KPa

KPa

KPa

KPa

DPM 15 12


R 1700 Loader

CAT 3176CEngine

Source: S McGinn

mg/m3 EC

37


CO

NO

NO2

O2

CO2

TGas

Turbo Boost Press

Intake Restriction

Charge Air Temp

Backpressure

Fuel Pressure

INLET OUTLET

2100 1700 1500

200 200

600 600

25 25

12 12

7 7

480 425

RPM

ppm

ppm

ppm

%

%

°C

110

3

45

22

450

°C

kPa

kPa

kPa

kPa

DPM 15 1


Source: S McGinn

R 1700 Loader

CAT 3176CEngine

mg/m3 EC

38


UOW Project by Jen Hines to test EBM

• Two underground Coal mines – an intervention site and a control site

• Fuel measurement

• Personal sampling of workers for DPM (as EC) & NO2

• Emissions Based Maintenance adopted at intervention site

• Looking for a reduction in diesel exhaust exposure to workers and a reduction in fuel usage to provide a catalyst for employers to implement EBM

39


-100%

0%

100%

200%

300%

400%

500%

A A A B B C D D D D EL FH GH GL

LHD - ManifoldPercentage (%) of Baseline

CO NOx DPM (EC)

% Comparison to Current Baseline Values

30% of baseline

15% of baseline


40


% Comparison to Current Baseline Values

-100%

-50%

0%

50%

100%

150%

200%

250%

300%

350%

M M N O O P Q R R R S S T U U V V V

Personnel Transport - ManifoldPercentage (%) of Baseline

CO NOx DPM (EC)

30% of baseline

15% of baseline


41


Pre and Post EBM

0

100

200

300

400

500

600

700

800

CO NO NO2 NOx

pp

m

Pre Injector change Post Injector change

0

10

20

30

40

50

mg

/m3

EC

DPM

524

200

48

245

32

Initial target value


42


Maintenance of Baseline – is it possible?

• Intervention mine has attempted to return all engines to within ±15% of their original baseline

• After maintenance campaign & standardising data on % CO2

about 50% of engines met the criteria (i.e. 50% failures)

• Is this a function of engine decay over time or unrealistic baseline values – both possibilities under investigation


43


Maintenance Issues – LHD

DPM

(mg/m3

EC)

Reduction

of DPM

(%)

Sampling

Point

Maintenance

Status

34 - ManifoldPre-

maintenance

24 29 TailpipePre-

maintenance

2 94 TailpipeDDEF canister

seals replacedSource: J Hines – Used with permission

4444


LHD - Exhaust Canister & DDEF

Reproduced with permission

45


Maintenance Issues Identified

Leaking seals around raw exhaust particulate filters

Old seal New seal


46


Maintenance Issues – LHD

Tailpipe CO

(ppm)

Exhaust

Backpressure

(kPa)

Test Date

230 4.5 Week 1

485 25 Week 5Source: J Hines – Used with permission

4747


Maintenance Issues Identified

Blocked scrubber tank exhaust pathway

48

Source: B Davies


Quote:

49

“If we were not doing this work (EBM) – we would not know this is occurring and possibly not do anything for 6 months until statutory samples failed”

Mechanical Engineer: Intervention mine


Progress over 12 months: Personal Sampling – DPM

Exposure Guideline 0.1mg/m3 EC


50


Conclusions To Date• Current practice does not ensure engine emissions meet

baseline comparison criteria – but are the baseline requirements realistic?

• Routine monitoring of exhaust emissions can identify engine (and control technology) faults quickly

• Changing past practices requires a team approach (management, diesel mechanics, operational personnel, support staff)


51


Pros – EBM and Exposure• Early detection of faults• Investigation into faults – can they be prevented?• Understanding results• Reduced exposure to workers• Reduced costs – blocking scrubber tank uses 4 to 6

filters a shift• Improved planning – blocking scrubber tank occurs

over a month – time to plan and improve turnaround time

• Where you reduce DPM, you reduce fuel usage


52


Cons – EBM and Exposure

• Effort is required to schedule testing, train diesel maintenance personnel & implement onsite

• Interpretation and management of data can be a burden


53


What's Next?

• Multi-national project to assist sites in making EBM sustainable by remotely interpreting emissions data in real time and suggesting engine or control technology faults

• Same system will allow scheduling of testing, engine profiling and comparison between participants

54


Acknowledgements

• Southern African Institute of Occupational Hygiene

• Anglo American plc

• Jen Hines

• University of Wollongong

55

diesel particulate matter control strategies in the mining ...€¦ · turbo boost press intake...

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