Upload
others
View
8
Download
0
Embed Size (px)
Citation preview
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
Same Engine Over Time
Why are results lower on these two tests?
8
© 2018 – Dr B Davies AM
Different Engines But Same Type & Approximate Age
1 2 3 4 5 6 7
9
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
Raw Exhaust Testing Equipment
Equipment must be suitable for use by site personnel
Source: J Hines
11
© 2018 – Dr B Davies AM
Intake Restriction & Backpressure Measurement
Source: S McGinn
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
• 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
© 2018 – Dr B Davies AM
Source: Jeanot Tourneur
Exhaust Velocity from MT6020
15
© 2018 – Dr B Davies AM
Sampling Points
16
Source: B Davies
© 2018 – Dr B Davies AM
Maintenance Personnel Performing a Gas Test
17
Source: B Davies
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
• 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
© 2018 – Dr B Davies AM
DPM Test Procedure
Source: MDG 29 2008
20
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
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
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 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
Diesel Oxidation Catalyst
R 1700 Loader
CAT 3176CEngine
Source: S McGinn30
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 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
Diesel Oxidation Catalyst
R 1700 Loader
CAT 3176CEngine
Source: S McGinn31
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 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
Diesel Oxidation Catalyst
R 1700 Loader
CAT 3176CEngine
Source: S McGinn
32
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 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
Diesel Oxidation Catalyst
R 1700 Loader
CAT 3176CEngine
Source: S McGinn
33
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 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
Diesel Oxidation Catalyst
R 1700 Loader
CAT 3176CEngine
Source: S McGinn
34
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 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
Diesel Oxidation Catalyst
R 1700 Loader
CAT 3176CEngine
Source: S McGinn
35
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 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
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 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
Diesel Particulate Filter
R 1700 Loader
CAT 3176CEngine
Source: S McGinn
mg/m3 EC
37
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 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
Diesel Particulate Filter
Source: S McGinn
R 1700 Loader
CAT 3176CEngine
mg/m3 EC
38
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
-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
Source: J Hines – Used with permission
40
© 2018 – Dr B Davies AM
% 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
Source: J Hines – Used with permission
41
© 2018 – Dr B Davies AM
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
Source: J Hines – Used with permission
42
© 2018 – Dr B Davies AM
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
Source: J Hines – Used with permission
43
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
LHD - Exhaust Canister & DDEF
Reproduced with permission
45
© 2018 – Dr B Davies AM
Maintenance Issues Identified
Leaking seals around raw exhaust particulate filters
Old seal New seal
Source: J Hines – Used with permission
46
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
Maintenance Issues Identified
Blocked scrubber tank exhaust pathway
48
Source: B Davies
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
Progress over 12 months: Personal Sampling – DPM
Exposure Guideline 0.1mg/m3 EC
Source: J Hines – Used with permission
50
© 2018 – Dr B Davies AM
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)
Source: J Hines – Used with permission
51
© 2018 – Dr B Davies AM
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
Source: J Hines – Used with permission
52
© 2018 – Dr B Davies AM
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
Source: J Hines – Used with permission
53
© 2018 – Dr B Davies AM
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
© 2018 – Dr B Davies AM
Acknowledgements
• Southern African Institute of Occupational Hygiene
• Anglo American plc
• Jen Hines
• University of Wollongong
55