As the first attempt of its kind in the country, Seoul Metropolitan Government launched a trial program for the reduction of nitrogen oxides emitted by vehicles using 400 LPG taxis.
Under said program, the city replaced for free the three-way catalytic converters (TWC) installed in LPG taxis whose performance guarantee period has passed with new ones to maintain the function of nitrogen oxide reduction.
Usually, owners scrap a taxi that has run 500,000km, which takes 4~6 years. However, since the TWC performance guarantee period ends at 192,000㎞, the nitrogen oxides reduction function starts to deteriorate.
TWC is a device that facilitates the conversion of hydrocarbon, nitrogen oxides, and carbon monoxide existing in emissions into carbon dioxide, nitrogen, and vapor (H2O) to reduce the emission of polluted gas through a self-purification system.
According to Seoul Metropolitan Government, it adopted said program since no additional measure has been prepared concerning the obligatory installation of TWC on gasoline and LPG vehicles, which account for 68.7% of all vehicles in the city.
Vehicles participating in said program are 400 Sonata taxis owned by 17 taxi companies whose initial date of registration falls on 2010 or 2011 and which have run more than 200,000km. The free installation of TWC was carried out in May at the business jointly selected by Seoul City and the Ministry of Environment.
The Seoul Metropolitan Government will expand the scope of the program to more LPG taxis and gasoline vehicles after checking the effect of the first round of the program. It will also apply the program of installing a PM (particulate matter)-NOx reducing device in large-sized cargo trucks and buses.