Study On Spraying Oxidation Rate Of Magnesium Sulfite

In recent years, the pollution of the ship exhaust gas has caused extensive concern. The flue gas desulfurization can control the emission of sulfur oxides effectively. In the present flue gas desulfurization technology, magnesium desulfurization technology has the characters of high desulfurization efficiency, system stability, less occupied area, low investment and so on, thus there is a tendency to replace the calcium desulfurization gradually.As the by-product of magnesium-based seawater flue gas desulfurization, the oxidation rate of magnesium sulfite in the spraying process was mainly studied in this thesis. In the fresh water system, oxidative factors, such as the initial pH value of solution, temperature, the initial concentration of magnesium sulfite, spray pressure, nozzle type have been separately studied about their effects on the oxidation rate of magnesium sulfite by single factor experiments. Oxidative factors such as the initial pH value of solution, temperature, the initial concentration of magnesium sulfite were carried out to determine the primary and secondary sequence affecting the oxidation rate of magnesium sulfite.For the characteristics of magnesium-based seawater flue gas desulfurization using seawater as the process water, oxidative factors such as the initial pH value of solution, temperature, the initial concentration of magnesium sulfite have been separately studied about their effects on the oxidation rate of magnesium sulfite by single factor experiments in the seawater system..The experimental results show that in the fresh water system, the oxidation rate of magnesium sulfite decreases with the increasing of the initial pH value; the oxidation rate of magnesium sulfite firstly increases and then decreases with the increasing of temperature; under the unsaturated condition, the oxidation rate of magnesium sulfite increases with the increasing of initial concentration of magnesium sulfite, while the results was opposite under the saturated state. Hollow cone nozzle and spray pressure of 0.10MPa is beneficial for high oxidation rate. The primary and secondary order of the factors affecting the oxidation of magnesium sulfite is:initial concentration of magnesium sulfite> temperature> initial pH value of solution.In the seawater system, the oxidation rate of magnesium sulfite in each initial pH value is lower than that of the fresh water system. With the increasing of the temperature, the oxidation rate of magnesium sulfite is faster than that of the fresh water system gradually. Under the unsaturated condition, the oxidation rate of each concentration is higher than that of the fresh water system, and the result was opposite under the saturated state.