The process of SO_2 absorption by basic aluminum sulfate solution and aluminum sulfate solution with different parameters was experimentally studied. The results show that, with the increasing SO_2 absorption, the p H value of both the basic aluminum sulfate solution and aluminum sulfate solution declined, But the active Al3+ in the basic aluminum sulfate solution has a strong buffering effect on the p H value's drop.In the basic aluminum sulfate solution, SO_2 reacted with the active Al3+ firstly, when the...