| 摘要 |
PURPOSE: A defrosting apparatus of a pipe for a selective catalytic reduction system, and a control method thereof are provided to improve efficiency of a defrosting apparatus by enabling selective defrosting of a specific section when freezing is diagnosed in the specific section based on the freezing diagnosis results. CONSTITUTION: A defrosting apparatus of a pipe for a selective catalytic reduction system comprises piping (50), a dosing valve (41), a reverting valve (42), a cut valve (43), a pump (60), a pressure detecting unit (70), a first bypass line (110), a second bypass line (120), and multiple heaters. The dosing valve is placed in one side of a nozzle (30) in the piping in order to control the discharge of a urea solution. The reverting valve is placed in the piping in order to control the flow of the urea solution in a forward direction or a backward direction. The cut valve is placed in one side of a urea tank (80) in the piping in order to control the suction of the urea solution. The pump is placed in the piping and passes through the reverting valve, thereby forming pressure to pump the urea solution. The pressure detecting unit is placed in the downstream of the reverting valve in the piping in order to detect the pressure of the urea solution. One side of the first bypass line is connected to the upstream of the dosing valve in the piping, and the other side is connected to the urea tank so that the urea solution can be collected in the urea tank by a first valve (112). One side of the second bypass line is connected to the upstream of the reverting valve in the piping, and the other side is connected to the urea tank so that the urea solution can be collected in the urea tank by a second valve (122). The heater heats a selected section in the piping depending on the opening or closing state of the first and the second bypass lines. |
