Any railroad corporation or other body heretofore granted the right or power to build and maintain a railroad in this state, for a limited number of years, and which now owns a railroad in this state, built and maintained pursuant to such grant or power, has all the rights and privileges as are conferred by any general statutes of this state upon railroad corporations, and may exercise the same without regard to and despite any limitations of years contained in any such original franchise or grant.
T.C.A. § 65-6-104