Technical Reports

Assessment of Control Techniques for Reducing Emissions from Locomotive Engines

  • 01
  • Nov
  • 1973
AUTHOR: J. O. Storment, K. J. Springer
SUBJECT: Environmental Protection
KEYWORDS: Diesel Engines, Air Pollution, Environmental Impact
ABSTRACT: The primary objective of this study was to determine the most effective method of reducing emissions of oxides of nitrogem from a two-cylinder version of an EMD series 567C locomotive engine. The control method judged most effective was that which resulted in the greatest reduction in NOx, had the least adverse effects on other emission constituents and engine operation, yet was simple to install and maintain. The NOx control techniques selected for use in this study included: (1) change in fuel injector design, (2) variation in injection timing from the standard setting, (3) inlet air humidification (water induction), (4) reduction of scavenging air volume (air box bleed) and (5) exhaust gas re-circulation (EGR). In addition, methods (2) and (3) were used in combination. Results of these tests indicated that the most effective control method was retarded injection timing (4° from standard). The next most effective method was EGR, with the recirculated exhaust cooled to 125-150°F. It was necessary to derate (or reduce) engine power at certain points to maintain smoke opacity at acceptable levels with all of these control techniques.