An exhaust gas purifying facility of a combustion engine includes: a marine combustion engine (16); a reducing device (12) for feeding urea water into an exhaust gas in an exhaust gas line (16L) of the marine combustion engine (16); and a generation device (20) for generating the urea water from urea powder (U). The generation device (20) includes a storage-generation tank device (30) and an adjustment tank device (40) capable of adjusting the density of the urea water. The storage-generation tank device (30) has a storage-generation tank (31) for storing the urea powder (U) and feeding water to the urea powder (U) for dissolution. The adjustment tank device (40) has an adjustment tank (41) for storing the urea water withdrawn from the storage-generation tank (31).
