Oil component and sludge component collection tank

An oil-collecting system having a return pipe that returns from an oil sending pipe of sending an upper layer of an oil/water separation tank to the oil/water separation tank via an oil and sludge collecting tank,

• wherein the oil-collecting system conducts an oil collecting using a plurality of the oil and sludge collecting tanks from one oil/water separation tank,
• wherein the oil and sludge collecting tank that temporarily stores an upper layer of an oil/water separation tank, and that collects oil and sludge, comprising:
• an upper tank into which the upper layer of the oil/water separation tank flows through an inflow pipe;
• at least one or more lower tank that has a smaller volume than the upper tank, and that is continuously provided from the bottom surface of the upper tank;
• and
• a lower tank heating means that heats the lower tank,
• wherein the oil-collecting system comprises a flow path switching part that switches the route from the oil/water separation tank to the plurality of the oil and sludge collecting tanks according to the amount of floating oil in the oil and sludge collecting tank, and
• wherein the flow path switching part is installed in the oil sending pipe.