A further recovery system for residual heat of flue gas, comprising: a housing of upright thin-wall hollow cylinder shape, a rotating core coaxially installed in the upper part of the housing and capable of rotating around its central axis, a partition plate installed in the housing and passing through the central axis of the housing and the rotating core , a baffle plate , a spray device , and a water-water heat exchanger with a heat release unit connected to a water inlet and a water outlet of the spray device ; wherein the rotating core is a upright thick-wall hollow cylinder, the longitudinal cross section of the side wall of the rotating core is honeycomb-like, the interiors of which are coated with desiccant material(s), the partition plate divides the internal space of the housing and the rotating core into an air flow channel and a flue gas flow channel , a plurality of baffle plates are respectively installed between the top of the housing and the top of the rotating core , between the top of the rotating core and the top of the partition plate on the flue-gas-flow-channel side, between the bottom of the rotating core and the partition plate on the air-flow-channel side, and between the bottom of the rotating core and the housing on the flue-gas-flow-channel side, the top of the rotating core on the air-flow-channel side forms an air flow channel inlet , an air flow channel outlet is provided in the lower wall of the housing on the air-flow-channel side, a flue gas flow channel inlet and a flue gas flow channel outlet are respectively provided in the lower wall and upper wall of the housing on the flue-gas-flow-channel side, and the spray device is installed in the flue gas flow channel in the lower part of the housing . a housing of upright thin-wall hollow cylinder shape, a rotating core coaxially installed in the upper part of the housing and capable of rotating around its central axis, a partition plate installed in the housing and passing through the central axis of the housing and the rotating core , a baffle plate , a spray device , and a water-water heat exchanger with a heat release unit connected to a water inlet and a water outlet of the spray device ; wherein the rotating core is a upright thick-wall hollow cylinder, the longitudinal cross section of the side wall of the rotating core is honeycomb-like, the interiors of which are coated with desiccant material(s), the partition plate divides the internal space of the housing and the rotating core into an air flow channel and a flue gas flow channel , a plurality of baffle plates are respectively installed between the top of the housing and the top of the rotating core , between the top of the rotating core and the top of the partition plate on the flue-gas-flow-channel side, between the bottom of the rotating core and the partition plate on the air-flow-channel side, and between the bottom of the rotating core and the housing on the flue-gas-flow-channel side, the top of the rotating core on the air-flow-channel side forms an air flow channel inlet , an air flow channel outlet is provided in the lower wall of the housing on the air-flow-channel side, a flue gas flow channel inlet and a flue gas flow channel outlet are respectively provided in the lower wall and upper wall of the housing on the flue-gas-flow-channel side, and the spray device is installed in the flue gas flow channel in the lower part of the housing . <EOS>