A post-treatment system includes two SCRs, a second SCR is connected to a booster in parallel, and a three-way valve is arranged before the second SCR and the booster, such that whether an exhaust gas flows through the second SCR or the booster is controlled by means of controlling the three-way valve. In the case of a low temperature, the three-way valve is controlled to close a branch of the booster, such that the exhaust gas flows through the second SCR and a first SCR that are connected in series, thereby reducing the energy loss caused by the exhaust gas flowing through the booster, and improving the NO.sub.x conversion efficiency in the case of a low temperature. In a case of a high temperature, the three-way valve is controlled to close a by-pass line, such that the exhaust gas flows through the booster and the first SCR.

A reductant insertion system for an after treatment system configured to decompose constituents of an exhaust gas, includes: a dry reductant tank configured to contain a dry reductant; a reductant delivery line configured to operatively couple the dry reductant tank to the after treatment system for delivery of the dry reductant to the after treatment system; and a pressurized gas source configured to communicate the dry reductant to the after treatment system through the reductant delivery line using pressurized gas.

An exhaust aftertreatment system for increasing fractional efficiency of diesel or gasoline particulate filters includes a particulate filter that includes a housing and a filter substrate positioned in the housing. The filter substrate is pre-conditioned with an aqueous solution or suspension configured to decompose or evaporate in response to exposure to heat so as to precondition the filter substrate.

An exhaust gas purification device (26) for a gas turbine engine (10) comprises a catalyst chamber (64, 96) defined in an exhaust gas passage (22), a reduction agent container (32) containing a solid material that releases a reduction agent gas effective for NOx reduction when heated, a heating device (36, 38) for heating the solid material contained in the reduction agent container, and a reduction agent gas supply passage (48) for supplying the reduction agent gas released from the solid material into the catalyst chamber.

A reductant insertion system for an after treatment system configured to decompose constituents of an exhaust gas, includes: a dry reductant tank configured to contain a dry reductant; a reductant delivery line configured to operatively couple the dry reductant tank to the after treatment system for delivery of the dry reductant to the after treatment system; and a pressurized gas source configured to communicate the dry reductant to the after treatment system through the reductant delivery line using pressurized gas.

An exhaust aftertreatment system for increasing fractional efficiency of diesel or gasoline particulate filters includes a particulate filter that includes a housing and a filter substrate positioned in the housing. The filter substrate is pre-conditioned with an aqueous solution or suspension configured to decompose or evaporate in response to exposure to heat so as to precondition the filter substrate.

An exhaust aftertreatment system for increasing fractional efficiency of diesel or gasoline particulate filters includes a particulate filter that includes a housing and a filter substrate positioned in the housing. The filter substrate is pre-conditioned with an aqueous solution or suspension configured to decompose or evaporate in response to exposure to heat so as to precondition the filter substrate.

An exhaust aftertreatment system for increasing fractional efficiency of diesel or gasoline particulate filters includes a particulate filter that includes a housing and a filter substrate positioned in the housing. The filter substrate is pre-conditioned with an aqueous solution or suspension configured to decompose or evaporate in response to exposure to heat so as to precondition the filter substrate.

A post-treatment system includes two SCRs, a second SCR is connected to a booster in parallel, and a three-way valve is arranged before the second SCR and the booster, such that whether an exhaust gas flows through the second SCR or the booster is controlled by means of controlling the three-way valve. In the case of a low temperature, the three-way valve is controlled to close a branch of the booster, such that the exhaust gas flows through the second SCR and a first SCR that are connected in series, thereby reducing the energy loss caused by the exhaust gas flowing through the booster, and improving the NO.sub.x conversion efficiency in the case of a low temperature. In a case of a high temperature, the three-way valve is controlled to close a by-pass line, such that the exhaust gas flows through the booster and the first SCR.

The present disclosure relates to a method of compacting an ash deposited in a particulate filter for a vehicle exhaust gas system, the method includes the steps of: a) providing a low-temperature melting salt to the particulate filter, thereby forming a mixture of the ash and the low-temperature melting salt: and b) heating the particulate filter to a compaction temperature, thereby compacting the mixture of the ash and the low-temperature melting salt. The disclosure further relates to engine oils, dosage products, engine systems and vehicles for implementing such a method.