An adaptive method is used for LNT desulfation and regeneration. The desulfation method involves adapting the amount of sulfur loading to trigger a desulfation event in accordance with the current adsorption capacity of the LNT. The method involves monitoring the current sulfur loading and the current LNT adsorption capacity. This data is used to calculate a loading amount "trigger", whose value varies over the LNT lifetime. Whenever this trigger amount is reached, a desulfation event is performed. The regeneration method is similar, with the baseline data and loading threshold being determined by NOx loading rather than sulfur loading.
Qilong Lu; Shizuo Sasaki; Yiqun Huang