Waseda University

Nissan Diesel Motor Co., Ltd.

Ud Trucks Corporation

Tokyo Roki Co., Ltd.

Takayuki Adachi

Kiminobu Hirata

Nobuhiko Masaki

Masakazu Yano

Isamu Kanaya

Jin Kusaka

Fumiyuki Tsurumi

Keishi Takada

Takeshi Mende

An exhaust gas pressure P, exhaust gas temperatures Tand Ton upstream and downstream of a DPF, a rotation speed Ne, a load Q, and an intake flow rate F as various operating conditions are read, and an amount of PM generated for short time &#x394;t is obtained to be added to a PM deposited amount m, and thus, to obtain an initial deposited amount. Exhaust gas properties and a space velocity SV are obtained based on various operating conditions, and the PM deposited amount m after a lapse of the short time &#x394;t is estimated from a PM deposited amount estimation equation 'm=m&#xb7;exp(&#x2212;B&#xb7;&#x394;t)' having been derived considering the exhaust gas properties and the space velocity SV. When the PM deposited amount m is equal to or more than a predetermined value, a forced regeneration processing in the DPF is executed, and thereafter, the PM deposited amount m is reset to 0.

Apparatus for and method of purifying exhaust gas

An exhaust gas purification apparatus includes an NOx reduction catalytic converter disposed in an engine exhaust passage to reductively purify NOx in exhaust gas using ammonia or its precursor as a reducing agent, a first concentration sensor which detects an ammonia concentration in an exhaust gas moving on a downstream side of the NOx reduction catalytic converter, and a control unit which incorporates therein a computer. The control unit conducts calculation to estimate an ammonia concentration in the exhaust gas moving on the downstream side of the NOx reduction catalytic converter, and when a difference between the ammonia concentration detected by the first concentration sensor and the estimated ammonia concentration by the calculation becomes larger than a first predetermined value, determines that the NOx reduction catalytic converter is deteriorated.

Exhaust gas purification apparatus

Growing community of inventors

Ageo, Japan

Takayuki Adachi