Energy-saving sludge drying disposal system

An energy-saving sludge drying disposal system, comprising:

• a vacuum heating unit and an incinerating unit, and further comprising a vacuum cooling unit and a molten salt heat exchanging unit;
• wherein the vacuum heating unit comprises a tank, a heating chamber provided in the tank and longitudinally coaxial with the tank, a gas-liquid separating device provided in the tank and arranged above the heating chamber, and a mixed gas outlet connected with the gas-liquid separating device and arranged on the top wall of the tank;
• the heating chamber comprises an outer shell, an inner shell, a heating cavity provided between the outer shell and the inner shell, a sludge inlet provided at one side wall of the inner shell, a sludge outlet provided at another side wall of the inner shell, a spiral compression device provided in an inner cavity of the inner shell in a penetrating manner and corresponding to the sludge inlet and the sludge outlet respectively at both ends, a water inlet provided at one side wall of the heating chamber, and a water outlet provided at another side wall of the heating chamber, a top wall of the inner shell is connected with several gas discharging pipes going through the top wall of the outer shell and connected with the gas-liquid separating device;
• and the water inlet is connected with the high-temperature liquid outlet of the molten salt heat exchanging unit;
• the vacuum cooling unit comprises a cooling tank, a high-temperature gas inlet provided at the top wall of the cooling tank, a condensed water outlet provided at the bottom wall of the cooling tank, a low-temperature gas outlet and a low-temperature liquid inlet provided at one side of the cooling tank, a medium-temperature liquid outlet provided at the other side of the cooling tank, and a cooling pipe provided in the cooling tank and connected respectively between the low-temperature liquid inlet and the medium-temperature liquid outlet at both ends;
• the high-temperature gas inlet of the vacuum cooling unit is connected with a mixed gas outlet of the vacuum heating unit;
• the incinerating unit comprises an incinerator, and an incineration gas inlet, a combustion-supporting gas inlet, a fuel oil inlet, a flue gas discharge outlet, a cold molten salt inlet and a hot molten salt outlet provided in sequence on a wall of the incinerator, and a heating molten salt pipeline arranged in the incinerator and connected to the cold molten salt inlet and the hot molten salt outlet respectively at both ends;
• the incineration gas inlet is connected with the low-temperature gas outlet of the vacuum cooling unit;
• the molten salt heat exchanging unit comprises a heat exchanger shell, and a cold molten salt outlet, a hot molten salt inlet, a medium-temperature liquid inlet and a high-temperature liquid outlet provided on the heat exchanger shell, a heat exchanging molten salt pipeline arranged in the heat exchanger shell and connected between the cold molten salt outlet and the hot molten salt inlet at both ends;
• the cold molten salt outlet is connected with the cold molten salt inlet of the incinerating unit, and the hot molten salt inlet is connected with the hot molten salt outlet of the incinerating unit;
• the medium-temperature liquid inlet is connected with the medium-temperature liquid outlet of the vacuum cooling unit, and the high-temperature liquid outlet is connected with the vacuum heating unit.