Homogenitätsanalyse von Feststoffmischungen

Research output: ThesisMaster's Thesis

Organisational units

Abstract

Untreated polymers are rarely produced to semi-finished or finished products. Special technological properties and workability can only be achieved by the addition of fillers and reinforcing agents, plasticizers, lubricants, pigments and stabilizers. A good and homogeneous material quality of the extrudate is only given if a constant mixing of these additives to the polymer can be achieved. Therefore the solid pre-mixing has an important influence for the quality. If the agents are not fixed by bonding forces or if they are not bound immediately after the mixing into the granulate separation by the transport can occur. The reason for this is the difference between the polymer and the agents, especially in the shape, grain size and weight. In this master thesis a valuation method for the quality of the homogeneity of the solid mixture which is supplied to the extruder using the pneumatic conveying of the mixing aggregates was found. Then the next step was to create a quality valuation method to compare different mixing and transporting systems. The developed quality valuation method was realized in a special measuring station. Also an error estimation and verifying the reproducibility of the measuring station was done based on the first series of tests. The homogeneity and the quality difference of two defined standard mixtures in dependence of different transport tracks were measured. • The homogeneity of the solid mix which leaves the dosing and mixing aggregates. • The homogeneity of the solid mix which is produced by a 10 m horizontal transport in the material funnel. • The homogeneity of the solid mix which is produced by a 10 m vertical transport in the material funnel. It was found out that the developed measuring station provides very good test results with just a negligible error. It also was found out that there isn’t any noticeable difference between the horizontal and vertical transport under the same conditions. Rather it was proven that the influence of the mixer is many times higher than the effect of sucking.

Details

Translated title of the contributionHomogeneity analysis of solid mixtures
Original languageGerman
QualificationDipl.-Ing.
Supervisors/Advisors
Award date8 Apr 2011
Publication statusPublished - 2011