Urea depollution circuit comprising a double-seat valve selectively ensuring the degassing or the recirculation of the aqueous urea solution

摘要

The invention concerns a circuit intended to transfer, by means of a pump, first fluid, such as an aqueous urea solution, from a reservoir to an injector, said circuit also containing a second fluid, such as air, and said circuit comprising, downstream of the pump and of the reservoir, a downstream circuit portion which includes, on the one hand, a main branch which leads to the injector and, on the other hand, bypass branch which returns to the reservoir and which is provided with a double-seat valve designed to selectively and automatically adopt: purge configuration allowing to purge the second fluid through the valve out of the main branch, a pressurized supply configuration allowing to direct the first fluid to the injector under a predetermined working pressure, and a recirculation configuration allowing a recirculation through the bypass branch, and to the reservoir, of the first fluid coming from said reservoir.