This paper focuses on the robust mixed H2/H∞ observer design problem for removal of NOx sensor ammonia cross-sensitivity in selective catalytic reduction (SCR) systems. Due to the ammonia cross-sensitivity, the reading of the NOx sensor is contaminated severely. In order to utilize the concentration of the NOx in the downstream tailpipe, it is desired to design an observer to estimate the actua...

Photo-chemical smog and acid rain formed from many pollutants including NOx are serious problems that have attracted much attention due to their negative influences on the atmosphere, plants, animals and even building materials. Effective measures of controlling NOx emissions are necessary. In this study, a computational fluid dynamics (CFD) software, Ansys Fluent 14.5, has been applied to rese...

This paper reports plasma treatment of a 5 HP stationary diesel engine exhaust at full flow-rate (approximately 387 l/min) energized by power frequency AC. Glass and Chlorinated Polyvinyl Chloride (CPVC) tubes were used as the dielectric barriers. Significant removal of NO and NOx has been achieved with barrier discharge plasma. The reactors were specially fabricated to facilitate high flow and...

Wet scrubbing combined with ozone oxidation has become a promising technology for simultaneous removal of SO2 and NOx in exhaust gas. In this paper, a new 20-species, 76-step detailed kinetic mechanism was proposed between O3 and NOx. The concentration of N2O5 was measured using an in-situ IR spectrometer. The numerical evaluation results kept good pace with both the public experiment results a...

Introduction Removal of harmful NOx emissions from lean burn and diesel engines in the presence of excess oxygen presents a great challenge. Lean-NOx traps (LNTs, aka NOx storage/reduction (NSR) catalysts or NOx adsorbers) are one of the promising technologies to remove NOx effectively. In the LNT technology, an active (alkali and/or alkaline earth) oxide material takes up NOx under lean engine...

In this study, experiments have been conducted to evaluate the organics and nutrients removal from synthetic wastewater by a laboratory scale moving bed biofilm process. For nutrients removal, moving bed biofilm process has been applied in series with anaerobic, anoxic and aerobic units in four separate reactors. Moving bed biofilm reactors were operated continuously at different loading rates ...