ENGINE SYSTEM WITH WATER-EMULSION FUEL DRAIN RECYCLING DEVICE

To return a water-emulsion fuel drain discharged through a drain port of a fuel injection pump apparatus to a circulation line within a comparatively short storage time to recycle the water-emulsion fuel drain as a water-emulsion fuel. An engine system (11) includes: a circulation line (17) in which the water-emulsion fuel circulates; a fuel injection pump apparatus (15) including a fuel inlet (32) through which the water-emulsion fuel is supplied from the circulation line (17) and a fuel outlet 41 through which the water-emulsion fuel is returned to the circulation line (17); an engine main body (29) to which the water-emulsion fuel is supplied by the fuel injection pump apparatus (15); a water-emulsion fuel drain storage tank (52) configured to store the water-emulsion fuel drain discharged through a drain port (16) of the fuel injection pump apparatus (15); and a second return line (54) and a drain injection pump (55), each configured to return the water-emulsion fuel drain stored in the drain storage tank (52) to the circulation line (17).