| 摘要 |
<p>The present invention provides a reducing agent supply apparatus capable of recovering and returning a liquid reducing agent to a storage tank without using a reversely rotatable pump or a valve for switching the connection of flow paths. During a period in which liquid reducing agent injection control is executed, the reducing agent supply apparatus connects an inlet line (31) of a pump (23) with a storage tank (21) and drives the pump (23). During a period in which liquid reducing agent recovery control is executed, the reducing agent supply apparatus opens the inlet line (31) of the pump (23) to the atmosphere and drives the pump (23) to return the liquid reducing agent to the storage tank (21) via a return line (37) which connects a reducing agent injection unit (50) and the storage tank (21).</p> |
