摘要 |
A urea backflow prevention apparatus of Selective Catalytic Reduction (SCR) system that injects a urea aqueous solution to an exhaust pipe may include a urea tank storing the urea aqueous solution, a nozzle being installed on the exhaust pipe and injecting the urea aqueous solution into the exhaust pipe, a supply pump pressurizing the urea aqueous solution in order to inject the urea aqueous solution from the nozzle to the exhaust pipe, a suction line supplying the urea aqueous solution stored in the urea tank to the supply pump by connecting the urea tank and the supply pump, a pressure line delivering the urea aqueous solution pressurized at the supply pump to the nozzle by connecting the supply pump and the nozzle, and a return line collecting urea aqueous solution not injected at the nozzle to the urea tank by connecting the supply pump and the urea tank. |