oxidation catalyst offers particular ad- vantages in this area, said Emitec, as the exhaust gas is deflected and flows back through an inner tube. Urea is injected into the deflection chamber so that, given an optimum mixture, hydrolysis already occurs inside the component. The first, small SCR is fitted downstream, still close to the engine. The close-cou- pled design of these compact metal components was designed to ensure rapid heating for catalyst light-off and to be highly effective under the engine cycle conditions commonly found in nonroad applications. Emitec said NOx emissions are substantially reduced in the first SCR stage. In combination with a second SCR, the system can achieve NOx conversion rates of 90 to 95%, Emitec said. The company said that modern engines with high- pressure fuel injection and highly effective turbocharging will require no other emissions control technolo- gy than SCRa to achieve Tier 4 interim and Tier 4 final.
ENGINE CONTROL SYSTEMS Engine Control Systems has intro- duced the Purifilter Plus, which combines the Combifilter’s active regeneration with Purifilter’s passive operation to provide a hybrid that allows “boost regeneration” for cold- er duty cycles. It has CARB Level 3 verification and reduces PM by 90%. The system is applicable to 1993 to 2006 engines and is available in six models that can be customized for specific applications. To date, Engine Control Systems has supplied approximately 400 to 450 Purifilter and Purifilter Plus sys- tems to drayage truck operators serv- ing the Port of Oakland, Calif. Engine Control Systems’ TermiNOx D, a urea-based selective catalytic reduction (SCR) system, is listed on the National Clean Diesel Cam- paign’s Emerging Technology List. SCR is used to inject urea into the
exhaust stream, which then decom- poses to produce ammonia (NH3). ECS said the TermiNOx D reduces PM by 25%, CO by 85%, HC by 85% and NOx by 65%. The Actifilter SG is another one of ECS’s emerging technologies. It has a modular design and uses onboard diesel fuel to generate syngas for DPF regeneration. It is currently in durability trials on a number of vehi- cle demonstrations with both EGR and non-EGR equipment. It is antic- ipated to meet the low NO2 limits of Level 3 Plus verification.
ESW GROUP ESW has developed the Therma Cat Level 3 Plus active diesel particu- late filter (DPF) for on- and off-road, medium- and heavy-duty diesel en- gines and the Xtrm Cat diesel oxida- tion catalyst (DOC) for marine and rail applications. ESW achieved verifica- tions from CARB, with testing con- ducted at ESW’s Air Testing Services division. The Therma Cat is an active DPF that achieves more than 96% reduction of diesel particulate matter and over 90% reduction of HC and carbon monoxide and is designed for a wide variety of on-road and off-road diesel engine applications. The Therma Cat and Xtrm Cat are CARB verified. This verification is also wide- ly accepted and transferable to Australia and the Asian markets, such as China and Korea, ESW said. ESW’s Therma Cat is an active Level 3 Plus system that has passed Federal Motor Vehicle Safety Standard 301 for fuel system integrity on school buses. ESW has also worked closely with dis- tributors and end users to design sys- tems that have minimal impact on the safe and healthy operation of the vehi- cle by designing systems that fit in exist- ing engine compartments, eliminating driver visibility issues, especially for off- road applications. ESW has fitted more than 200 Therma Cat units in 2009 in a combination of on- and off-road applica- tions from school buses, municipal vehi-
38 DIESEL PROGRESS NORTH AMERICAN EDI TION February 2010
TECHNOLOGY OF CLEAN AIR
cles and off-road construction equip- ment such as wheel loaders and exca- vators. ESW said it also has the ability to design systems for the off-road sec- tor that allow the Therma Cat DPF to be retrofitted under the hood in the existing OEM muffler location. ESW was also part of two successful grant opportunities, one with Mississippi River Corridor in Tennessee that will see 13 Xtrm Cat DOC kits installed on six barges operated by Ingram Barge Co. on the Mississippi River, and one with Puget Sound Clean Air Agency that will see four Xtrm Cat DOC kits installed on two vessels operated by Foss Maritime in Puget Sound. ESW also installed its first Xtrm Cat DOC on a rail engine operated by Dallas Area Rapid Transit commuter trains with three addi- tional engines to be retrofitted in 2010.
A diesel particulate filter system that GTE has developed for a rail application.
GTE Industries has received a Level 3 Plus verification from CARB for its PurityLine of catalyzed diesel particu- late filters. GTE Industries’ Purity cDPF acts as a silencer and a filter for partic- ulate matter (PM). It can be purchased as either a separate unit that can be installed in front of an existing silencer or as a new silencer/filter combination that can be installed in place of the existing silencer to meet sound attenu- ation and emissions control needs. CARB has verified GTE Industries Purity DPF system as a Level 3 Plus device for Tier 1, Tier 2 or Tier 3 certi- fied off-road engines used in station- ary prime and emergency standby generators and pumps. The GTE