Experimental Research On Magnesium Slag For Desulfurtion By Fluidized Bed Reactor

Because of the extensive application of magnesium and magnesium alloys, the metal magnesium industry has rapidly developed. However, there exists some pollutions from magnesium slag during the magnesium production. With the development of metal magnesium industry, this issue has become more obvious. How to utilize magnesium slag has become an issue that people pay more attention to. At present the pollution from magnesium slag till exists. It is necessary to study an effective way on solution for the pollution from magnesium slag in order to bring great social and ecological benefits.In this thesis, the author takes magnesium slag as a sorbent to study the desulfurization performance of the magnesium slag in a fluidized bed reactor. The results show that the particle size of the metal magnesium has significant effect on desulfurization performance. When average particle sizes are separately 0.303mm and 0.713mm, the calcium utilization reaches 15.83% and 9.6%. O2 and SO2 concentration have similar effect on the desulfurization performance. The higher the concentration is, the higher the calcium utilization of magnesium slag. The reaction temperature also has significant influence on the desulfurization performance. When reaction temperature increases from 800 ℃to 1000℃, the calcium utilization changes from 13.03% to 20.47%, and the desulfurization efficiency increases to 63.53%. It was also found that the water-cooled metal magnesium slag has an effectively improve in desulfurization compared with natural-cooled metal magnesium slag. Water-cooled processing method is a kind of effective methods in improving desulfurization performance of the magnesium slag.Experimental results by component analysis show that the main composition of metal magnesium slag is Ca2SiO4, and CaO and MgO are in the minority. It is Ca2Si04 and CaO that play a leading role in desulphurization reaction, and MgO has little or no effect in sulfurization reaction. The surface area and pore volume of magnesium slag are determined by N-absorption before and after the desulfurization. In comparison with the natural-cooled magnesium slag, the water-cooled magnesium slag has a significantly increases in both BET surface area and pore volume, respectively increase by 17.2 times and 14.9 times. The results from SEM shows that the surface of the water-cooled magnesium slag has a great improve in pore distribution. Some floccules are generated which may provide more surface areas and pore volumes for desulfurization reaction. Therefore the water-cooled magnesium slag has an effectively improve in desulfuration compared with natural-cooled magnesium slag.This thesis studies the desulfurization performance of magnesium slag in a fluidized bed reactor. Some conclusions may provide guidance for magnesium slag as the sorbent used in fluidized bed boilers.