Abstract:
A process for removing metallic impurities from a product mass flow comprising water-absorbing polymer particles by means of bar magnets, wherein the water-absorbing polymer particles comprise a surfactant and have direct contact with the bar magnets.
Abstract:
Process for classifying a particulate water-absorbing resin using a sieving apparatus at a reduced pressure compared with the ambient pressure and a sieving apparatus for classifying a particulate water-absorbing resin at a reduced pressure compared with the ambient pressure.
Abstract:
A process for continuously producing water-absorbing polymer particles, comprising polymerization, drying, grinding, classification and at least partial recycling of the undersize obtained in the classification, wherein the polymer gel obtained by the polymerization is withdrawn from the polymerization reactor and mixed with the recycled undersize.
Abstract:
A process for removing metallic impurities from a product mass flow comprising water-absorbing polymer particles, wherein the product mass flow has a temperature of 35 to 90° C.
Abstract:
A process for producing water-absorbing polymer particles, wherein an aqueous polymer gel is dried in a forced-air belt drier on a circulating conveyor belt and the surface of the conveyor belt has a roughness of at least 0.9 μm.
Abstract:
A process for producing water-absorbing polymer particles, comprising polymerization, drying, comminution, classification and recycling of the undersize obtained in the classification, wherein the recycled undersize is coated with a reducing agent and/or inorganic particles.
Abstract:
A process for producing water-absorbing polymer particles, wherein a polymer gel is removed from a polymerization reactor, stored intermediately as a particulate polymer gel in a delay vessel, removed by means of a first conveying device at the lower end of the delay vessel and dried, the intermediately stored particulate polymer gel being conveyed within the delay vessel by means of at least one second conveying device above the first conveying device in the direction of the first conveying device.
Abstract:
A process for producing water-absorbing polymer particles by polymerizing droplets of a monomer solution in a gas phase surrounding the droplets, wherein the particle surface is coated at least partly with at least one polymer and/or wax.
Abstract:
A process for producing water-absorbing polymer particles, comprising the addition of a solid additive to a polymer gel by means of a conveying screw (1), wherein the solid additive and a gas volume flow are fed to the conveying screw (1) by means of an addition channel (2).
Abstract:
In a process for producing water-absorbing polymeric particles by suspension polymerization, a monomer solution is metered into a stirred reactor via at least one feed line, the stirred reactor has a volume of at least 1 m3 and the at least one feed line ends in the stirred reactor at a point less than 25 cm above the liquid surface.