Preliminary Investigation of the Correlation Between In-use Diesel Engine PM Emission Rates and Opacity

Transcription

1 212 PEMS Conference and Workshop Preliminary Investigation of the Correlation Between In-use Diesel Engine PM Emission Rates and Opacity John Karim, Section Manager In-Use Retrofit Section Mobile Source Control Division El Monte, California

2 212 PEMS Conference and Workshop Study Objective The series of testing was initially designed to examine gaseous emission concentrations and particulate matter (PM) mass emission levels for a variety of on-road and off-road diesel engines. With the addition of snap-acceleration opacity testing, the study led to indicate that a strong correlation may exist between PM mass emission rates (g/bhp-hr) and opacity (%). If a strong correlation is established, opacity testing can be used as a simple in-field measurement tool for evaluating engine conditions and diesel-particulate filter (DPF) performance. Quick infield evaluations may be used to supplement extensive engine testing in preparation for DPF retrofit installations. Test Methods 4 CFR 165 compliant gravimetric PM mass analysis SAE J1667 compliant opacity testing Laser photometer Electrical detection

3 212 PEMS Conference and Workshop Diesel Engine Test Series Test I: Test II: Test III: Future Testing: On-road and Off-road Diesel Engines (Urban Bus and Others) Transport Refrigeration Unit (TRU) Diesel Engine ARB Field Vehicle Diesel Engine Continued Testing of On-road and Off-road Diesel Engines

4 212 PEMS Conference and Workshop Emissions Measurement Equipment Gaseous and PM Mass Emissions PM Mass Emissions DUSTTRAK SEMTECH-DS Pegasor URG Dual Phase filter BOSCH RTT 1 Opacity Red Mountain Dekati Mass Monitor (DMM)

5 Test Cell vs. PEMS USO6-1 USO6-2 USO6-3 USO6-4 SS5-1 SS5-2 SS5-3 USO6 SS5 Total Exhaust Volume (ft3) PEMS Cell %Diff Fuel Usage (gal) PEMS Cell %Diff PEMS CO2 (g) Cell %Diff PEMS CO (g) Cell %Diff PEMS NOx (corrected NOx as NO2) Cell 7 (g) %Diff PEMS THC (g) Cell %Diff Ford F L (Gasoline) grams per test

6 212 PEMS Conference and Workshop PEMS System Flow Schematic Exhaust DPF Exhaust Flow Meter Exhaust Filter Filter Diluter DUSTTRAK Diluter DUSTTRAK Other PM Devices PM #1 PM #2 Other PM Devices Remote Controller On-Board Control System ECM GPS Gas Analyzer Exhaust Signal

7 CO, ppm CO2, % NOx, ppm HC, ppm PEMS gas audit NIST Gas Check: PEMS NOx reading NIST Gas Check: PEMS HC reading % % %.9% PEMS NOx NIST cylinder NOx %.3% PEMS HC NIST cylinder HC NIST Gas Check: PEMS CO reading NIST Gas Check: PEMS CO2 reading % % % 1.2% PEMS CO NIST cylinder CO % PEMS CO2 NIST cylinder CO2

8 212 PEMS Conference and Workshop Test I: Urban Bus Testing Continuous, real-time measurements: Gaseous emissions (NO, NO 2, CO, CO 2, and THC) PM mass concentrations using gravimetric, electrical detection, and laser photometer methods Vehicle exhaust flowrate using engine electronic control module (ECM), or exhaust flowmeter (EFM) at the exhaust outlet Atmospheric conditions (temperature, pressure) and GPS data Snap-acceleration measurements: Opacity Continued real-time measurements during snap-acceleration procedure Engine mfr. Engine model series Displacement hp Rating Urban Bus Detroit Diesel DDC L 315 hp

9 212 PEMS Conference and Workshop Test I: Test Route Continuous PM mass emissions data was collected at the engineout location along the exhaust stream (prior to the DPF) while the buses were driven along typical urban routes. Subsequently, opacity measurements along with PM mass measurements were also taken at engine-out during snapacceleration test modes. Typical bus route followed during on-road PEMS testing

10 212 PEMS Conference and Workshop Test I: Test Results 1. Engine-out PM mass emission rates measured in real-time test mode correlated well (r =.89) with the CFR-compliant gravimetric method. 2. Engine-out opacity measurements also correlated well (r =.83) with engine-out PM emission rates measured in real-time test mode.

11 212 PEMS Conference and Workshop Test I: Additional Test Vehicles Trash Truck Tractor Scraper Engine year Engine mfr. Mack John Deere Caterpillar Engine model series AI 35 ASET IEGR 668HRW64A,B 348E Displacement 11.9 L 6.8 L 18 L hp Rating 35 hp 14 hp 457 hp On- or off-road On Off Off

12 212 PEMS Conference and Workshop Test I: Opacity vs. PM Results The linear relationship between percent opacity and PM mass emission rate data for on-road and off-road vehicles showed a strong correlation (r =.92). Rule of Thumb Given the strong correlation, a 1 x PM (g/bhp-hr) rule of thumb can be applied to infer percent opacity and vice versa.

13 212 PEMS Conference and Workshop Test II: TRU Testing An emissions test was conducted on a transport refrigeration unit (TRU) engine where PM mass emissions and opacity data were collected during three test modes: snap-acceleration with load, snap-acceleration without load and continuous measurements at rated RPM. TRU Engine year 28 Engine mfr. Engine model series Engine output On- or off-road Kubota V223-M-D1-E2B 25.5 kw, 195 RPM N/A

14 BOSCH, % BOSCH, % 212 PEMS Conference and Workshop Test II: Opacity vs. PM Peak opacity and PM mass emissions rate values were compared from snap-acceleration tests with and without load. Opacity data from the BOSCH appears to indicate that the instrument s resolution is not high enough for accurate and repeatable readings below 3%. Improved technology is needed for better repeatability at lower readings. DMM vs. BOSCH: Peak Values Pegasor vs. BOSCH: Peak Values y =.254x R² = y =.398x R² = DMM, mg/m3 DMM vs BOSCH Linear (DMM vs BOSCH) PEGASOR, mg/m3 PEGASOR vs BOSCH Linear (PEGASOR vs BOSCH)

15 Pegasor, mg/m3 212 PEMS Conference and Workshop Test II: Instrument Correlation The DMM and Pegasor PM mass concentration data showed a strong correlation. An adjustment factor of 2.4 was applied to the Pegasor data. DMM 14 Pegasor vs. DMM y =.6594x R² =.9944 PM correlation: DMM vs PEGASOR Linear (PM correlation: DMM vs PEGASOR) Pegasor DMM, mg/m3 DMM and Pegasor have a 13:1 dilution ratio Real-time, continuous measurements Electrical detection operation.2-sec response time

16 DUSTTRAK (mg/m 3 ) 212 PEMS Conference and Workshop Test II: Instrument Correlation The DMM and DUSTTRAK PM mass concentration data showed a strong correlation with R 2 =.973. DMM 2 DUSTTRAK vs. DMM y = x R²=.973 DMM vs. DustTrak DUSTTRAK 12 1 Linear (DMM vs. DustTrak) DMM (mg/m 3 ) DUSTTRAK has a 1:1 dilution ratio Real-time, continuous measurements Electrical detection operation (DMM) Laser photometer operation (DUSTTRAK)

17 DUSTTRAK, mg/m3 212 PEMS Conference and Workshop Test II: Instrument Correlation The Pegasor and DUSTTRAK PM mass concentration data showed a strong correlation with R 2 =.921. Pegasor DUSTTRAK vs. Pegasor y = 1.716x R²=.921 PM correlation: DustTrak vs PEGASOR DUSTTRAK Linear (PM correlation: DustTrak vs PEGASOR) Pegasor, mg/m3 Real-time, continuous measurements Electrical detection operation (Pegasor) Laser photometer operation (DUSTTRAK)

18 212 PEMS Conference and Workshop Test III: ARB Field Truck Testing An emissions test was conducted on our own field vehicle. PM mass emission measurements were collected during a real-world driving test mode. Additionally, opacity data was collected using a snapacceleration test mode while continuing real-time PM mass emission measurements. Field Truck Engine year 29 Engine mfr. Engine model series hp Rating Engine displacement Navistar Power Stroke diesel V8 325 hp 6.4 L

19 9:7:44 9:8:52 9:1: 9:11:8 9:12:16 9:13:24 9:14:32 9:15:4 9:16:48 9:17:56 9:19:4 9:2:12 9:21:2 9:22:28 9:23:36 9:24:44 9:25:52 9:27: 9:28:8 9:29:16 8:4:4 8:41:22 8:42:4 8:43:58 8:45:16 8:46:34 8:47:52 8:49:1 8:5:28 8:51:46 8:53:4 8:54:22 8:55:4 8:56:58 8:58:16 8:59:34 9::52 9:2:1 9:3: PEMS Conference and Workshop Test III: Instrument Correlation T e s t R u n # 1 PM concentration, mg/m DMM vs. PEGASOR, mg/m 3 DMM corrected, mg/m3 PEGASOR corrected, mg/m3 DMM, mg/m DMM vs. PEGASOR, mg/m 3 y = x R² = DMM vs PEGASOR Linear (DMM vs PEGASOR) PEGASOR, mg/m 3 T e s t R u n # 2 PM concentrations, mg/m DMM vs. PEGASOR, mg/m 3 DMM corrected, mg/m3 PEGASOR corrected, mg/m3 DMM, mg/m DMM vs. PEGASOR, mg/m 3 y = 1.317x R² = DMM vs PEGASOR Linear (DMM vs PEGASOR) PEGASOR, mg/m 3

20 1:4:15 1:5:11 1:6:7 1:7:3 1:7:59 1:8:55 1:9:51 1:1:47 1:11:43 1:12:39 1:13:35 1:14:31 1:15:27 1:16:23 1:17:19 1:18:15 1:19:11 1:2:7 1:21:3 1:21:59 9:35:23 9:36:3 9:37:37 9:38:44 9:39:51 9:4:58 9:42:5 9:43:12 9:44:19 9:45:26 9:46:33 9:47:4 9:48:47 9:49:54 9:51:1 9:52:8 9:53:15 9:54:22 9:55:29 9:56: PEMS Conference and Workshop Test III: Instrument Correlation T e s t R u n # 3 PM concentrations, mg/m DMM vs. PEGASOR, mg/m 3 DMM corrected, mg/m3 PEGASOR corrected, mg/m3 DMM, mg/m DMM vs. PEGASOR, mg/m y = 1.952x R² =.826 DMM vs PEGASOR Linear (DMM vs PEGASOR) PEGASOR, mg/m 3 DMM vs. PEGASOR, mg/m 3 DMM vs. PEGASOR, mg/m3 T e s t R u n # 4 PM concentrations, mg/m DMM corrected, mg/m3 PEGASOR corrected, mg/m3 DMM, mg/m PEGASOR, mg/m 3 y = x R² =.8675 DMM vs PEGASOR Linear (DMM vs PEGASOR)

21 212 PEMS Conference and Workshop Future Testing Further emissions measurements and data collection will be conducted in order to substantiate the correlation between percent opacity and PM mass emission rates. The ability to rely on the use of opacity testing will become valuable for quick and efficient in-field evaluations of: Engines before retrofit installations, and DPF conditions during the course of the demonstration projects. Test vehicles will continue to include on-road and off-road diesel engine vehicles. A number of different instruments will be employed for cross-checking and correlating measurement data. The reliability and accuracy of each instrument will also be taken into consideration in post-test analyses.

22 212 PEMS Conference and Workshop Summary and Conclusion Opacity testing can be used to conduct in-field evaluations of engines before retrofit installations, as well as DPF conditions after installation Opacity meters in the market need to be more accurate and repeatable at lower-end readings There is a need for more reliable technology to conduct in-field evaluations of engines and DPF retrofits, especially in order to quickly determine a compromised DPF The DUSTTRAK and Pegasor can be reliable instruments for evaluating PM emissions

23 Thank you In-Use Retrofit Section John Karim, Jesse Tu, Gloria Pak, George Gatt, Tony Nassar, Svetlana Espinosa, Tung Tran, Stephanie Maalouf, Robert Cabral, Mark Real, Patrick Chang, Nick Le