The present invention provides an apparatus and a method for producing magnesium sulfate through flue gas desulfurization, and specifically provides an apparatus and a method suitable for producing magnesium sulfate through direct crystallization in a magnesium oxide based desulfurization waste liquid tower of flue gas with a small content of oxygen like a coal fired boiler flue gas. The apparatus includes an oxygenation equipment, a flue gas desulfurization equipment, a seriflux cycling equipment, an evaporation and concentration equipment, a cycling and precipitating equipment, an oxidation equipment, a crystallization equipment, a centrifugation equipment and a drying equipment, etc. The apparatus and method of the present invention can greatly reduce electric power consumption of oxidation fans and steam consumption, as well as guarantee desulfurization efficiency and quality of a magnesium sulfate by-product, reduce lots of operation costs of the magnesium sulfate production system, and reduce desulfurization operation costs.

The present invention provides an apparatus and a method for producing magnesium sulfate through flue gas desulfurization, and specifically provides an apparatus and a method suitable for producing magnesium sulfate through direct crystallization in a magnesium oxide based desulfurization waste liquid tower of flue gas with a small content of oxygen like a coal fired boiler flue gas. The apparatus includes an oxygenation equipment, a flue gas desulfurization equipment, a seriflux cycling equipment, an evaporation and concentration equipment, a cycling and precipitating equipment, an oxidation equipment, a crystallization equipment, a centrifugation equipment and a drying equipment, etc. The apparatus and method of the present invention can greatly reduce electric power consumption of oxidation fans and steam consumption, as well as guarantee desulfurization efficiency and quality of a magnesium sulfate by-product, reduce lots of operation costs of the magnesium sulfate production system, and reduce desulfurization operation costs.

A method of capturing carbon dioxide, including providing a particle containing magnesium oxide, calcium oxide, or a combination thereof; and providing a mixture gas to contact the particle, wherein the mixture gas includes water vapor, carbon dioxide, and nitrogen oxide, and the particle captures the carbon dioxide to form a carbonated particle and a treated gas. The mixture gas has a relative humidity of 25% to 95%, a nitrogen oxide concentration of 20 ppm to 2000 ppm, and a carbon dioxide concentration of 0.05% to 15%.

A method of capturing carbon dioxide, including providing a particle containing magnesium oxide, calcium oxide, or a combination thereof; and providing a mixture gas to contact the particle, wherein the mixture gas includes water vapor, carbon dioxide, and nitrogen oxide, and the particle captures the carbon dioxide to form a carbonated particle and a treated gas. The mixture gas has a relative humidity of 25% to 95%, a nitrogen oxide concentration of 20 ppm to 2000 ppm, and a carbon dioxide concentration of 0.05% to 15%.