Technology reduces heavy-duty diesel emissions to meet stringent CARB 2027 NOx requirements

Southwest Analysis Institute (SwRI) demonstrated the effectiveness of its CAT-DEF expertise throughout the WCX World Congress Expertise in Detroit, which befell April 5–7. The development efficiently decreased heavy-duty diesel engine nitrogen oxide (NO_x) emissions to fulfill the California Air Sources Board (CARB) 2027 requirements.

CAT-DEF, which stands for Catalyzed Diesel Exhaust Fluid, is an SwRI-developed catalyst- and surfactant-modified diesel exhaust fluid (DEF) answer. As we speak’s diesel engines use selective catalytic discount (SCR), a complicated emissions management system, to abate NO_x emissions. DEF is injected into the exhaust stream and ideally decomposes to kind ammonia, which reacts with NO_x on the SCR catalyst to kind N₂ and H₂O.

Though the present course of is comparatively environment friendly at temperatures higher than 250°C, at temperatures beneath 250°C, urea-derived deposits kind inside the aftertreatment system. These deposits severely restrict low-temperature NO_x conversion and improve gas consumption as high-temperature engine operations are required to take away the deposits.

SwRI’s novel expertise decreases NO_x and carbon dioxide emissions for diesel engines by considerably lowering undesirable deposit formation in exhaust techniques.

“Though DEF expertise has been utilized for greater than a decade, the very best emissions management efficiencies may by no means be realized because of DEF’s tendency to create doubtlessly dangerous deposits within the exhaust system, notably when the engine is operated at low masses and temperatures,” mentioned Dr. Charles E. Roberts Jr., director of SwRI’s Industrial Car Programs Division. “A mix of surface-active brokers and heterogenous catalysts blended into CAT-DEF reduces deposits by 90% with potential reductions as much as 98%.”

SwRI engineers studied the expertise’s effectiveness for lowering NO_x emissions on the new requirements set by CARB—recognized for enacting stricter requirements than the Environmental Safety Company—by means of a head-to-head comparability of diesel engines operated with and with out CAT-DEF.

“We demonstrated that utilizing CAT-DEF allowed an engine to fulfill or exceed upcoming CARB 2027 NO_x necessities, whereas utilizing customary DEF didn’t meet the brand new customary,” mentioned SwRI Analysis Scientist Dr. Grant Seuser, considered one of CAT-DEF’s principal investigators, who, alongside his fellow researchers, shared the findings throughout a session on system integration and sturdiness at WCX. “Our findings present that DEF can now be utilized over a wider vary of engine operation, reducing general NO_x emissions.”

SwRI’s CAT-DEF expertise is presently out there to license. The novel innovation is backwards-compatible and can be utilized in present engines as a deposit discount answer. For future functions, which shall be required to fulfill extra stringent regulatory necessities, the award-winning CAT-DEF answer competes with higher-cost engine {hardware} modifications presently being thought of by the diesel engine trade and DEF producers.