In the biochemical process, such as ethanol fermentation, some problems such as high nonlinearity and poor stability cause more difficulties on the optimal control of the fed-batch process. In order to solve these problems and improve the optimization efficiency as well as maximizing the product concentration, rolling optimization strategy is proposed based on the core idea of predictive control. In the optimization process, the penalty function method was used to transform the original optimization problem with constraints into an unconstrained optimization problem. And hybrid optimization algorithm combining ant colony algorithm and iterative dynamic programming has been applied into the substrate flow rate control trajectory optimization. Compare this new optimization algorithm with ant colony algorithm, the simulation results show that some performances such as optimization speed, optimization performance have been improved greatly.

According to the conditions of the low level of automation and low labour productivity，an automatic control system for flotation
process was designed and developed innovatively based on the ControlLogix series software and hardware platform of Ｒockwell Company．
The structure and function of the control system are introduced carefully． The control strategies of the pulp level，the air flowrate
and the flotation reagent feeding are described in detail． The control software and human － machine interface are designed and developed．
The actual industrial application results show that the control system operates steadily，safely and reliably，the worker labor intensities
are decreased obviously，and the work condition is improved，the competitiveness of the enterprise is enhanced．