abstract |
A two phase liquid mixture of a thermoplastic synthetic resin melt and an aqueous phase, such as a latex coagulate, is dewatered in a counter-rotating twin screw extruder under a pressure which is greater that the water vapor pressure at the temperature of the melt of the thermoplastic synthetic resin by conveying the melt into partially filled screw channels in the dewatering zone and restricting it in at least one of these screw channels in the entry nip of the twin screws to create a local, narrowly limited, steep pressure gradient and to form a coherent melt cake, and draining the water in liquid form from beneath under gravity upstream from the boundary of the melt cake so that the melt cake does not stand in contact with a coherent aqueous phase. |