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Verified Technologies for SmartWay and Clean Diesel

DonaldsonTechnology—Low NO2 Diesel Particulate Filter for Non-Road Applications (NR-LNF DPF) System

This retrofit technology is included on EPA's Verified Technologies List for Clean Diesel.

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Technology specifications

Engine Model/Application

Non-road, Tier 1 or Tier 2 diesel engines certified, maximum PM level of 0.25 g/bhp-hr, power rating 75 ≤ Kilowatts < 450 (100.6 ≤ Horsepower < 603.4) 

Retrofit Fuel, Max Sulfur 15 parts per million (ppm)
Reduction in particulate matter (PM) 90%
Reduction in nitrogen oxide (NOx) n/a
Reduction in hydrocarbons (HC) 95*%
Reduction in carbon monoxide (CO) 90%

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Criteria to achieve emission reductions

The following criteria must be met in order for appropriately retrofitted engines to achieve the aforementioned emission reductions:

  1. The engine must be operated on ultra-low sulfur diesel fuel (ULSD) of 15 ppm or less.
  2. The NR-LNF DPF System requires an exhaust temperature profile sufficient for regeneration. For engines with certification levels of 3.0 to 8.0 g/bhp-hr NOx and 0.01 to 0.11 g/bhp-hr PM, a duty cycle with a Weighted Average Temperature (WAT) at or above 250°C or at least 40% above 245°C (Category 1). For the engine group with emission certification of 5.0 to 8.0 g/bhp-hr NOx and 0.11 to 0.25 g/bhp-hr PM, a duty cycle with a WAT at or above 320°C or at least 40% above 320°C (Category 2). For the engine group with emission certification of 3.0 to 4.99 g/bhp-hr NOx and 0.11 to 0.25 g/bhp-hr PM, a duty cycle with a WAT at or above 362°C or at least 40% above 372°C (Category 3).
  3. Donaldson approved dealer shall perform an engine pre-assessment that assures the engine is at a minimum operating condition to prevent excess soot build up and that checks the maximum flow rate necessary for installation. The dealer will provide the owner with a copy of the pre-assessment.
  4. Donaldson approved dealer will install the Donaldson Emissions Device Monitor with the NR-LNF DPF System to constantly monitor backpressure and temperature on all vehicles equipped with this diesel particulate filter.
  5. The NR-LNF DPF System can be applied to engines with a maximum PM certification level of 0.25 g/bhp-hr.
  6. The engine must be well maintained and not consume lubricating oil at a rate greater than that specified by the engine manufacturer.
  7. The vehicle may not be equipped with an oil burning system and lube oil or other oils may not be mixed with the fuel.
  8. The engine must not have been originally certified or equipped with a diesel particulate filter.

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Verification Letter from EPA

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