Energy Infrastructure - Engine Customer Upgrades Doosan 22L System to Achieve EPA and Low Limit Emissions Targets - MIRATECH

Energy Infrastructure – Engine Customer Upgrades Doosan 22L System to Achieve EPA and Low Limit Emissions Targets


In late 2022, MIRATECH visited an engine customer in the Rocky Mountains with its Aftermarket Dealer, RJ Mann, to discuss upgrades to the Doosan 22L engine application. The engine upgrade to a different turbocharger resulted in increased horsepower, flow rates, and other changes to the engine operating conditions, including changes to the raw emissions output. The customer previously tested the MIRATECH Three-way Beast 9” custom housing, having very good results at the standard engine conditions. Based on the new operating conditions of the engine, the customer requested from MIRATECH a solution to meet EPA limits of 1g NOx and 2g CO, as well as a Low Limits solution of .2g NOx and .3g CO.


There are multiple application challenges the MIRATECH team had to consider related to this retrofit opportunity:

  • Ease of Installation: the customer requested a retrofit solution that could be implemented with minimal accommodation.
  • Size and Weight: the customer requested a compact solution that would fit within the limited space available inside the housing enclosure and keep additional weight to a minimum.
  • Increased Flow Rate: The 22L engine upgrades increased the exhaust flow rate from 4,038 lbs./hr. to 4,699 lbs./hr. This is a 16% increase.
  • Scalable Solution: the customer requested a solution that would work across multiple engines and across multiple permit limits.
  • Port locations: the customer requested all the pre- and post-catalyst ports be designed into the top half of the unit.
  • Order Fulfillment: the customer requested to retrofit 300 – 22L units in a short timeline, starting in June 2023 and shipping 50 engines per month. The 22L is a dual outlet requiring two housings.
  • Tight Emissions Targets: The low limit .2g NOx and .3g CO emissions targets are among the very lowest MIRATECH can warranty.


Between December 28th, 2022, and January 31st, 2023, two proposals were delivered to the customer that would meet their project challenges. The following is a summary of the custom engineered solution developed for the customer by the MIRATECH engineering team:

  • Engineering reviewed both the EPA Limit and Low Limits proposals for the increased flow rate and raw engine emissions numbers.
  • The flow rate increase from 4,038 to 4,695 lbs./hr. required a sized solution moving from the 9” RM past the 10.12” RM into the 14.5” RM.
  • The solution required increasing of the flange size from 4” to 5”. MIRATECH presented a standard ANSI 5” flange but communicated another option could be used if needed.
  • The solution called for one catalyst per bank to achieve the EPA emissions limit, and it called for two catalysts per bank to achieve the Low Limit targets.
  • MIRATECH offered the choice to utilize one or two elements to meet the requirements of the 8LNA, 8LTA, 11L, and 14L units.


The engineered solution was reviewed by the customer, and a virtual design review meeting was set up to review the proposed solution together. The meeting was attended by the customer development team, RJ Mann, and MIRATECH Engineering and Sales teams. Much of the discussion centered around the characteristics of the design to ensure the application would receive the best possible emissions reduction performance. A sales drawing and .step file were provided to the customer for final review following the meeting. Going forward, the customer was pleased with the options and will decide on the best path for purchase, installation, and testing of the new housing solution in preparation for a project supply award and the official start of production.

As a result of the comprehensive teamwork across all parties involved, MIRATECH has clearly shown itself to be a strong technical partner to the engine customer involved in this project and others in the future.