Micropump for viscous liquids and muds

This work was focused on the development of a micropump that allows the transport of fluids with high viscosities or fluid containing pigments in a large amount. This new pump should be produced by means of silicon micromachining technologies. Due to adhesion forces as well as sedimentation processes the transport of highly viscous and particle loaded fluids is a difficult problem. Dead volumes must be surely avoided in the pump because they are preferred regions of adhesion and sedimentation, respectively. The developed micropump is nearly free of dead volumes. It consists of silicon chips and a PTFE-membrane bonded together without real gluing procedures. The silicon chips contain deep etched structures manufactured by simple wet chemical etching procedures. Pressure on the lquid can be generated inside the structures by pushing the elastic membrane. A pneumatic drive was used to deflect the membranes. In a peristaltic mode it was possible to pump liquids like honey or mustard with a noticeable flow rate up to 0.6 ml/min without any back flow.