EXHAUST TREATMENT SYSTEM AND METHOD FOR TREATMENT OF AN EXHAUST STREAM

摘要

An exhaust treatment system is provided for treatment of an exhaust stream, where the system comprises a first dosage device, arranged to supply a first additive into said exhaust stream and a first reduction catalyst device, arranged downstream for reduction of nitrogen oxides in said exhaust stream through the use of said first additive, and for the generation of heat through at least one exothermal reaction with said exhaust stream. A particulate filter arranged downstream of said first reduction catalyst device to catch soot particles. A second dosage device arranged downstream of said particulate filter to supply a second additive into said exhaust stream and a second reduction catalyst device, arranged downstream of said second dosage device for reduction of nitrogen oxides in said exhaust stream through the use of at least one of said first and said second additive.

主权项

1. An exhaust treatment system arranged for treatment of an exhaust stream, which results from a combustion in a combustion engine, said system comprising:
a first dosage device arranged to supply a first additive into said exhaust stream; a first reduction catalyst device, arranged downstream of said first dosage device, and arranged for reduction of nitrogen oxides NOx in said exhaust stream, through the use of said first additive, said first reduction catalyst device comprising a first slip-catalyst (SC1) arranged primarily for carrying out a reduction of nitrogen oxides NOx, and secondarily for carrying out an oxidation of a residue of additive in said exhaust stream, and also for the generation of heat through at least one exothermal reaction with said exhaust stream, said generated heat enabling a regeneration of one or several components, through which said exhaust stream passes; a particulate filter, which is arranged downstream of said first reduction catalyst device, and is arranged to catch and oxidise soot particles; a second dosage device, arranged downstream of said particulate filter, and arranged to supply a second additive into said exhaust stream; and a second reduction catalyst device, arranged downstream of said second dosage device, and arranged for reduction of nitrogen oxides NOx in said exhaust stream through the use of at least one of said first and said second additive.