Abstract: A shell-and-tube heat exchanger includes a shell, heat transfer tubes, tube plates, covers, inlet and outlet for fluid flowing into and out of the shell, and inlet and outlet for fluid flowing into and out of the tubes, wherein the heat transfer tubes are corrugated heat transfer tubes, the tubing wall of the corrugated heat transfer tube is configured along the longitudinal direction of the corrugated heat transfer tube in a shape formed by tangentially connecting the crests of large arcs and the valleys of small arcs, the outside diameter D of the corrugated heat transfer tube is set at 1.3 to 1.5 times the inside diameter d, the corrugated heat transfer tubes are arranged spirally around the axis of the shell in multi-layers, and spiral plates are inserted between two layers of the corrugated heat transfer tubes.