pH值缓冲剂及烟气氧含量对软锰矿浆烟气脱硫体系的影响

Influence of pH Buffer and Oxygen Concentration in Flue Gas on the System of Flue Gas Desulfurization with Pyrolusite Pulp

软锰矿浆烟气脱硫工艺能利用软锰矿中的MnO2与烟气中的SO2反应生成副产品硫酸锰,喷射鼓泡反应器(JBR)适宜于该工艺体系,但在单级JBR反应器中进行软锰矿浆烟气脱硫很难同时实现较高的脱硫率(η(SO2))和锰浸出率(X(Mn))。针对这一问题,通过实验在JBR反应器中考察了pH值缓冲剂添加比例和烟气氧含量对软锰矿浆烟气脱硫体系的影响,确定烟气氧含量为21%时pH值缓冲剂的最佳添加比例为30%,烟气氧含量为7%时pH缓冲剂的最佳添加比例为10%。结果表明,在模拟燃煤烟气的条件下,体系中pH值缓冲剂的添加比例为10%时,可实现在单级JBR反应器内同时获得大于80%的脱硫率和锰浸出率的效果,证明该法不但具有在工艺操作上的可行性,还具有经济上的可行性,具有较好的工业化应用前景。

The flue gas desulfurization with pyrolusite pulp can produce the byproduct of manganese sulfate from the corresponding chemical reaction between MnO2 in pyrolusite and SO2 in flue gas, and moreover, Jet bubbling reactor（JBR） is the reactor that fits this technique very well. However, it is difficult to achieve the goal to obtain high enough SO2 absorption efficiency and Mn^2＋ extraction rate simultaneously in a single JBR. Thereafter, some research work about the effect of additive percentage of pH value buffer solution and oxygen concentration in flue gas on this system of flue gas desulfurization with pyrolusite pulp in a single JBR was carried out, and it was illustrated that the optimized additive percentage of pH value buffer was 30% and 10% when oxygen concentration in flue gas is 21% and 7% respectively. Based on the experiment results, it was proved that under the conditions of simulated flue gas from real flaming coal, if the additive percentage of pH buffer value was 10% , the SO2 absorption efficiency and Mn^2＋ extraction rate could both reach above 80% in a single JBR. Wherefore, it could be concluded that this technique of flue gas desulfufization is not only operationally but also commercially feasible, and also, promising in industrial application in the future.