Magnesium oxide desulfurization technology is a promising desulfurization process, which is relatively mature. Magnesium oxide desulfurization process was widely used all over the world. Among them, more than 100 projects have been applied in Japan. 95% of Taiwan’s power plants use magnesium oxide desulfurization technology, and it also applied in the USA, Germany, China etc.
The FGD process system is mainly composed of a magnesium hydroxide slurry preparation system, flue gas system, flue gas pretreatment system, SO2 absorption system, absorption tower evacuation system, desulfurization by-product slurry transport system and dehydration system, and water supply system. The principle of desulfurization of magnesium oxide is that the basic oxide reacts with water to form a hydroxide, and then reacts with a sulfurous acid solution formed by dissolving sulfur dioxide in water to carry out an acid-base neutralization reaction, and the magnesium oxide reacts to form magnesium sulfite.
Magnesium oxide (MgO) exists in the natural state as a free magnesite ore. Magnesite and dolomite are the main raw materials for producing magnesium oxide. In order to ensure good slaking performance and high desulfurization absorption capacity, magnesium oxide as a desulfurization absorbent should have the following main qualities:
| Color | White or light grayish white |
| Content of MgO | ≥90% |
| Content of CaO | ≤1.50% |
| Particle Size | 250-325 Mesh(45-60 Micron) |
| Loss on ignition (LOI) | <5.50% |
| HCl Insoluble | <0.20% |
| Chloride content(CI) | <0.15% |
| Sulfate Content(SO4) | <0.40% |
| Iron Content(Fe) | <0.10% |
| Manganese Content(Mn) | <0.007% |
| Silicon Dioxide Content(SiO2) | <0.40% |
| Stacking Density | 600-800kg/m3 |
