Resource recovery method and resource recovery system of desulfurized ash

A resource recovery method of desulfurized ash, comprising:

• a water washing process:
• washing desulfurized ash with water, and performing solid-liquid separation to obtain solid residues rich in calcium sulfite and calcium sulfate and a solution rich in calcium hydroxide;
• an analysis process:
• adding sodium carbonate and/or potassium carbonate to the solution, performing solid-liquid separation to obtain a salt solution and solid phase precipitates rich in calcium carbonate, and evaporating, concentrating and crystallizing the salt solution;
• and
• a roasting process:
• roasting the solid residues rich in calcium sulfite and calcium sulfate under the action of a reducing agent to obtain flue gas rich in sulfur dioxide and residues rich in calcium oxide.

A resource recovery system of desulfurized ash, comprising:

• a water washing reaction tank provided with a desulfurized ash delivery port and a water inlet;
• a solid-liquid separation device adapted to the water washing reaction tank and used for solid-liquid separation of mixed liquid in the water washing reaction tank;
• a desulfurized slurry preparation device communicated with a liquid phase outlet of the solid-liquid separation device;
• and
• a roasting reactor communicated with a solid phase outlet of the solid-liquid separation device and provided with a reducing atmosphere injection port, a roasting heating device, a temperature controller and a gas-solid separation device, wherein the temperature controller is connected to and controls the roasting heating device, and the gas-solid separation device is used to separate gas phase products and solid phase products in the roasting reactor.