Volatilization performance estimation apparatus and volatilization performance estimation procedure

摘要

A devolatilization performance prediction apparatus for a solution devolatilization process using a twin-screw extruder, comprising: a flow state calculation means (101) for computationally determining information relative to the flow state of a solution present in a devolatilization region (600), as the object of a devolatilization process in a spindle (200) that conveys the non-volatile mass solution containing volatile mass according to the flow state of the solution (700) present on the channel surface on the upstream side in the direction of transport of the spindle channel, of the solution (800) present in the gap between the spindle (200) and a drum (100) and of the solution (900) present on the channel surface on the downstream side in the direction of transport of the spindle channel; and a means of predicting devolatilization performance (102) to predict the devolatilization performance in the devolatilization process according to the information relative to the flow state computationally determined according to the flow state of the solution present in the spindle (200), in that the information regarding the flow state of the solution present on the channel surface on the upstream side in the direction of transport of the spindle channel is divided into two components that include the speed of dissolution flow flowing along of the spindle fillet and the dissolution flow rate that flows perpendicularly with respect to the spindle fillet, said two components being determined as a function of the spindle rotation speed, in which the means of predicting devolatilization performance (1 02) computationally predicts the devolatilization performance of a devolatilization process according to the following formula: in which L is the flow path length of the nonvolatile mass solution containing volatile mass in the devolatilization region (600), L2 is the length of the devolatilization region in the direction of spindle trees, C0 is the concentration of volatile mass at the inlet of the devolatilization region, C * is the equilibrium concentration of gas-liquid of volatile mass and non-volatile mass under the pressure / temperature conditions for devolatilization, CL is the volatile mass concentration after devolatilization, K1 is the ratio of the exposed surface length formed by a surface update flow within the residence time in the devolatilization region with respect to the exposed surface length of a profile for which no surface update is taken into account, K2 is the ratio of elapsed time to update r the surface exposed to the average flow rate between the drum (100) and the spindle (200) with respect to the residence time in the devolatilization region, K3 is the ratio of the elapsed time for updating the surface exposed to the peripheral speed of the spindle gear part with respect to the residence time in the devolatilization region, ρ is the density of the nonvolatile mass solution containing volatile mass, S1 is the length of the exposed surface of a profile for the that the filling ratio of the non-volatile mass solution containing volatile mass that fills the spindle channel is taken into account but for which no surface update is taken into account, S2 is the internal drum surface length, S3 is the length of the spindle channel part not fully filled with solution, Dd is the diffusion coefficient of the volatile mass contained in the non-mass solution volatile containing volatile mass, N is the spindle rotation speed, n is the number of threads of the spindle fillet, β is the efficiency of thin film formation of a thin film of dissolution in the gap produced between the drum (100) and the spindle (200), γ is the effectiveness of thin film formation of a thin film in the part of the spindle channel not fully filled with solution and Q is the overall processing rate, in which the Flow state calculation means (101) computationally determines the flow state of the solution (700) present on the spindle channel channel surface on the upstream side in the transport direction by the formulas shown below: and in which F is the flow propulsion speed of the solution flowing along the spindle fillet, E is the flow rate of the surface update flow, θ is the angle of Spindle fillet propeller, where the flow state calculation means (101) computationally determines the flow state of the solution (800) present in the gap between the spindle (200) and the drum (100) by the formulas shown then: and where F is the flow propulsion speed of the solution flowing along the spindle fillet, G is the average peripheral speed in the spindle tip section and W is the distance between the trees of the double spindle, in which the flow state calculation means (101) computationally determines the flow state of the solution (900) present on the channel surface of the spindle channel on the downstream side in the transport direction by the formulas shown below: and in which F is the flow propulsion speed of the solution flowing along the spindle fillet and I is the peripheral speed of the spindle gear part.