| abstract |
The invention relates to an injection device in an exhaust line (1), a gaseous reducing agent, comprising at least one gaseous reducing agent reserve (4, 5), a supply line (6). said agent, and at least one valve (70). The invention consists in that it comprises a reserve (8) of additional gaseous reducing agent called "emergency" connected by a conduit (9) to the supply line (6) of the reducing agent upstream of the valve (70), said duct (9) having a valve (10) operable only by a manual control device. |