DESULFURIZATION METHOD OF A NITROGEN OXIDE ABSORBING CATALYST SYSTEM CAPABLE OF DECIDING A DESULFURIZATION TIME BASED ON THE NUMBER OF SUCCESS IN THE REGENERATION OF A DIESEL PARTICULATE FILTER

摘要

PURPOSE: A desulfurization method of a nitrogen oxide absorbing catalyst system is provided to simplify the regeneration logic of desulfurization by deciding the desulfurization time based on the number of success in the regeneration of DPF(Diesel Particulate Filter), since all the trace sulfur compounds included in the exhaust gas ejected when the ultra low sulfur diesel oil is used become poison to an LNT(Lean NOx Trap) catalyst.;CONSTITUTION: A desulfurization method of a nitrogen oxide absorbing catalyst system comprises the following steps: determining(S110) whether the number of the success of DPF regeneration reaches the predetermined number of the success of DPF regeneration or not; performing(S120) desulfurization by terminating the DPF regeneration when the number of success of the DPF regeneration reaches the predetermined number of success of the DPF regeneration; entering the desulfurization mode; terminating(S160) the desulfurization after performing the desulfurization for the predetermined time; calculating and calibrating(S170) the amount of the collected PM-10(fine dust) in the DPF generated during the time of desulfurization after the termination of the desulfurization; determining the time for the following DPF regeneration; and comparing the temperature(T) of the inside of the nitrogen oxide absorbing catalyst with the deterioration temperature(X) of the nitrogen oxide absorbing catalyst during the time of the desulfurization.;COPYRIGHT KIPO 2013;[Reference numerals] (S100) Normal NO_X purification operation mode; (S110) Reaching a predetermined number of success of DPF regeneration?; (S120) Immediately entering a desulfurization mode after terminating the DPF regeneration; (S130) Maintaining a lambda(λ) value below a predetermined value; (S140) LNT catalyst inside temperature(T) Deterioration temperature(X) ?; (S150) Desulfurization for a predetermined time?; (S160) Terminating the desulfurization; (S170) Calculating and correcting the amount of PM collected in a DPF caused by PM produced during the desulfurization; (S180) Switching the mode to a normal lean operation for preventing overheating of catalyst; (S190) LNT catalyst inside temperature(T) ≤ Predetermined temperature(Y)