Continuously Regenerating Particulate Filters
Performance and Durability Evaluation of Continuously Regenerating Particulate Filters on Diesel Powered Urban Buses at NY City Transit
- Thomas Lanni, Division of Air Resources, New York State Department of Environmental Conservation
- Sougato Chatterjee, Ray Conway, Hassan Windawi, Diesel Emission Control Systems, Johnson Matthey, CSD
- Deborah Rosenblatt, Environment Canada
- Christopher Bush, Dana Lowell, New York City Metropolitan Transit Authority
- James Evans, Equilon Enterprises LLC
- Robert McLean, Corning Inc.
- Steven Levy, Rad Energy
Summary
Particulate emission from diesel engines is one of the most important pollutants in urban areas. As a result, particulate emission control from urban bus diesel engines using particle filter technology is being evaluated at several locations in the US. A project entitled "Clean Diesel Demonstration Program" was initiated by NY City Transit under the supervision of NY State DEC and with active participation from Johnson Matthey, Corning, Equilon, Environment Canada and Rad Energy.
Under this program, several NY City transit buses with DDC Series 50 engines were equipped with continuously regenerating diesel particulate filters (the CRTTM system from Johnson Matthey) and were operated with ultra low sulfur diesel (<30 ppm S) in transit service in Manhattan beginning in February 2000. The first phase of the program, reported here, consisted of a pilot project to verify the emissions reduction capability of the continuously regenerating diesel particulate filter technology with baseline emissions testing. The buses were evaluated over a 8-9 month period for operations, maintainability and durability of the particulate filter, including extensive emissions testing under transient cycles on a chassis dynamometer.
The on-road operational data over eight months showed stable exhaust back pressure with the particle filters, indicating successful filter regeneration. No adverse operational or maintenance issues were observed which could be attributed to the filter system. The emissions results from the first phase of testing exhibited >90% reductions in CO, HC and PM with the particulate filter. In addition, >99% reductions in carbonyls and up to 80% destruction of PAH and N-PAH were also achieved.
| Bus ID | Test Cycle | Configuration | Fuel | FE mpg |
CO2 g/mile |
NOx g/mile |
THC g/mile |
CO g/mile |
PM g/mile |
|---|---|---|---|---|---|---|---|---|---|
| NYCTA #6019 | CBD | OEM | LSD | 3.3 | 2942 | 25.6 | 0.18 | 1.8 | 0.22 |
| NYCTA #6019 | CBD | OEM | ULSD | 3.4 | 2948 | 25.6 | 0.06 | 1.2 | 0.19 |
| NYCTA #6019 | CBD | CRDPF | ULSD | 3.1 | 3236 | 26.4 | 0.03 | 0.16 | 0.04 |
| % Reduction baseline to ULSD | -0.2 | 0.0 | 66.7 | 34.7 | 15 | ||||
| % Reduction Baseline to ULSD & CRDPF | -10.0 | -3.1 | 83.3 | 91.4 | 82 | ||||
| NYCTA #6019 | NYBUS | OEM | LSD | 1.5 | 6483 | 70.3 | 0.91 | 13 | 0.65 |
| NYCTA #6019 | NYBUS | CRDPF | ULSD | 1.4 | 7177 | 70.3 | 0.06 | 0.23 | 0.04 |
| % Reduction Baseline to ULSD & CRDPF | -10.7 | -4.3 | 93.4 | 98.3 | 95.4 | ||||
| NYCTA #6065 | CBD | OEM | LSD | 3.3 | 2897 | 23.3 | 0.26 | 2.1 | 0.21 |
| NYCTA #6065 | CBD | OEM | ULSD | 3.5 | 2884 | 25.1 | 0.04 | 1.6 | 0.14 |
| NYCTA #6065 | CBD | CRDPF | ULSD | 3.7 | 2679 | 23.8 | 0 | 0.09 | 0.01 |
| % Reduction Baseline to ULSD | 0.5 | -7.6 | 85.7 | 23.9 | 31 | ||||
| % Reduction Baseline to ULSD & CRDPF | 7.5 | -2.1 | 100.0 | 95.9 | 95 | ||||
| Bus ID | Test Cycle | Configuration | Fuel | Carbonyl mg/mile |
PAH µg/mile |
NO2PAH µg/mile |
SO4 mg/mile |
SO2 mg/mile |
SOF % |
OC mg/mile |
EC mg/mile |
TC mg/mile |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| #6019 | CBD | OEM | LSD | 73 | 62 | 5 | 62 | 270 | 59 | 29 | 90 | 119 |
| #6019 | CBD | OEM | ULSD | 66 | 49 | 3.4 | 2.8 | 21 | n/r | 33 | 111 | 145 |
| #6019 | CBD | CRDPF | ULSD | bdl | 14 | 1.5 | 13 | 7 | bdl | 6.6 | 1.5 | 8.1 |
| % Reduction baseline LSD to ULSD | 10 | 22 | 32 | 95 | 92 | -14 | -23 | -22 | ||||
| % Reduction baseline LSD to ULSD with CRDPF | >99 | 78 | 70 | 79 | 97 | >99 | 77 | 98 | 93 | |||
| #6019 | NYB | OEM | LSD | 294 | 201 | 23 | 37 | 620 | 54 | 109 | 403 | 512 |
| #6019 | NYB | CRDPF | ULSD | bdl | 42 | 1.3 | 1.3 | 14.5 | bdl | bdl | bdl | bdl |
| % Reduction baseline LSD to ULSD with CRDPF | 79 | 94 | 96 | 98 | >99 | >99 | >99 | >99 | ||||
| #6065 | CBD | OEM | LSD | 77 | 66 | 3.8 | 37 | 316 | 65 | 42 | 90 | 133 |
| #6065 | CBD | OEM | ULSD | 70 | 63 | 2.6 | 3.9 | 31 | 68 | 26 | 82 | 110 |
| #6065 | CBD | CRDPF | ULSD | 0.9 | 15 | 0.5 | 2.6* | 7.4 | bdl | bdl | bdl | bdl |
| % Reduction baseline LSD to ULSD | 9 | 5 | 32 | 89 | 90 | -5 | 38 | 9 | 17 | |||
| % Reduction baseline LSD to ULSD with CRDPF | 99 | 78 | 87 | 93 | 98 | >99 | >99 | >99 | >99 | |||
- OC = Organic Carbon
- EC = Elemental Carbon
- SOF = Soluble Organic Fraction
- n/r = not reportable
- bdl = below detection limit
- * = large amount of error associated with this value analysis