The present invention relates to a floating LNG plant (1, 1′, 100) comprising a converted LNG carrier with a hull and a plurality of LNG storage tanks (4, 104) wherein in that the floating LNG plant (1, 1′, 100) comprises: —at least one sponson (2, 2′, 3, 3′, 102, 103) on the side of the hull, for creating additional hull volume, —process equipment (110) for LNG processing on the floating LNG plant (1, 1′, 100), and—a reservoir for storing fluids separated during the LNG processing, wherein said reservoir is formed by the ballast tank or in the space reserved for the ballast tank of the original LNG carrier.