Iron precipitation is the key process for iron removal in zinc hydrometallurgy.In iron precipitation process

it is very important to stabilize the pH value of the solution.However

the pH value fluctuates strongly in practice because of the nonlinearity and coupling in iron precipitation process. At first

the reaction kinetics mechanism of iron precipitation is analyzed.Then

the relationship between the pH value of the solution and the amount of zinc calcine (AZC) added into the solution is researched and the AZC added into the solution is calculated according to the technical requirement of pH value. At last

the parameter self-tuning fuzzy controller is proposed to adjust AZC added into the solution. Simulation results show that the parameter self-tuning fuzzy controller is very effective and it is a feasible method to stabilize pH value in iron precipitation process.