Stabilizing unstable operating points is an effective way to enhance process benefits and safety, which motivates the development for a variety of advanced control strategies. The washout filter-aided controller(WFC),...Stabilizing unstable operating points is an effective way to enhance process benefits and safety, which motivates the development for a variety of advanced control strategies. The washout filter-aided controller(WFC), originally used for electric power system and aircraft, has been introduced to adjust the dynamic behavior of chemical process. However, the parameter tuning method faces two major limitations: the dimension of operating variables must be equal to or greater than that of state variables and only one positive real eigenvalue exists in the open loop system. To overcome the two limitations, this paper proposes a new parameter tuning method, so that the WFC is applicable in most chemical processes. By solving a constrained optimization problem, the controller parameters are determined under the constraint that the reassignment of the eigenvalues of the unstable desired operating point can satisfy the stability condition. Thus parts of the equilibrium manifold including the desired operating point are stabilized without affecting the shape of the equilibrium manifold. Finally, the effectiveness of the WFC improved by the proposed parameter tuning method is illustrated through a case study for propanediol anaerobic fermentation.展开更多
For reducing moisture content of cake, the attempt is made by the use of surfactant in the dewatering of flotation concentrate. Different kinds of surfactant have been tested in laboratory and tbe factors which influe...For reducing moisture content of cake, the attempt is made by the use of surfactant in the dewatering of flotation concentrate. Different kinds of surfactant have been tested in laboratory and tbe factors which influence dewatering effect are investigated. Four of the surfactants have good dewatering efficiency.The moisture content is decreased by 5% or so. Two of them have been used in commercial process. The method is very simple and may solve a moisture problem of coal preparation plant.展开更多
基金Supported by the National Basic Research Program of China(2012CB720500)the National Natural Science Foundation of China(21306100)
文摘Stabilizing unstable operating points is an effective way to enhance process benefits and safety, which motivates the development for a variety of advanced control strategies. The washout filter-aided controller(WFC), originally used for electric power system and aircraft, has been introduced to adjust the dynamic behavior of chemical process. However, the parameter tuning method faces two major limitations: the dimension of operating variables must be equal to or greater than that of state variables and only one positive real eigenvalue exists in the open loop system. To overcome the two limitations, this paper proposes a new parameter tuning method, so that the WFC is applicable in most chemical processes. By solving a constrained optimization problem, the controller parameters are determined under the constraint that the reassignment of the eigenvalues of the unstable desired operating point can satisfy the stability condition. Thus parts of the equilibrium manifold including the desired operating point are stabilized without affecting the shape of the equilibrium manifold. Finally, the effectiveness of the WFC improved by the proposed parameter tuning method is illustrated through a case study for propanediol anaerobic fermentation.
文摘For reducing moisture content of cake, the attempt is made by the use of surfactant in the dewatering of flotation concentrate. Different kinds of surfactant have been tested in laboratory and tbe factors which influence dewatering effect are investigated. Four of the surfactants have good dewatering efficiency.The moisture content is decreased by 5% or so. Two of them have been used in commercial process. The method is very simple and may solve a moisture problem of coal preparation plant.
