Maximum likelihood identification of countercurrent rare earth extraction process based on state-space model

In this paper, the maximum likelihood identification problem of linear state-space models is considered for the rare earth extraction process. The maximum likelihood estimation is computed based on the expectation maximization algorithm. The mathematic expression of the conditional expectation is derived and the parameter choice for maximizing the conditional expectation is also presented. Finally, an real industrial experiment of rare earth extraction process is implemented and the results show the efficiency of the proposed method.