Experimental Analysis of LNT/DPF after Treatment System on a Passenger Car for Indian Road Condition

The Lean NOx Trap (LNT) / Diesel Particulate Filter (DPF) system has been developed as one of key technologies to comply with BS VI regulations. For DPF system it is necessary to prevent excessive soot accumulation and high temperature which can lead to eventual DPF failure. For LNT system it is necessary to maintain the NOx conversion efficiency to meet the required BS VI norms. Considering the Indian road condition a methodology was developed to evaluate the soot, de-NOx and de-SOx regeneration for development of optimized LNT/DPF system.

The study was carried on >1500cc, LNT/DPF equipped Euro VI diesel passenger car to evaluate the effect of regeneration characteristics in real Indian driving condition. The study was carried on different conditions such as traffic [urban mode and rural mode] and ambient condition like temperature and weather on the regeneration behavior of LNT/DPF. A concurrent study was conducted on the regeneration frequency, timing, temperature, success rate on the above mentioned methods which affects the life of the post-treatment system. The paper shows the correlation between the active & passive regeneration and Indian road condition for the development of BS VI. The focus of the study was on the system components and the information based on which regeneration is triggered. The paper will report on failure regenerations under several extreme conditions.