| 摘要 |
PROBLEM TO BE SOLVED: To avoid an excessive rise of a temperature of a filter at filter regeneration processing.SOLUTION: In an exhaust emission control system of an internal combustion engine which estimates an accumulation amount of particulate matters at each of partial regions which are divided into a plurality of zones in a filter which is arranged in an exhaust passage of the internal combustion engine, and oxidizes and removes the PMs which are accumulated in each region on the basis of an estimation result, when the accumulation amount of the particulate matters in a downstream-side partial region exceeds a downstream-side reference accumulation amount, a calorie for the filter regeneration processing is supplied so that a temperature of an upstream-side objective partial region which is located at an upstream side of a downstream-side partial region, and in which the accumulation amount of the particulate matters becomes maximum out of any of the partial regions including an upper-most upstream-side partial region is higher than a regeneration temperature, and that the temperature is accommodated within a temperature range in which the upstream-side objective partial region is not brought into an excessive temperature rise state, and when the accumulation amount of the particulate matters in the upstream-side objective partial region is large, a supply calorie per unit time for raising a temperature of the downstream-side partial region at the filter regeneration processing is set small compared with the case that the accumulation amount is small.SELECTED DRAWING: Figure 2 |
