Burkert has supplied Profibus-compatible valves on a new batching system for the ultra-pure chemicals plant of Rockwood Electronic Materials, at Riddings in Derbyshire, UK. At this site, Rockwood Electronic Materials produces ultra-pure processing chemicals and mixtures for use in the manufacture of silicon wafers and semiconductor devices. An upgraded, automated mixtures production plant has been commissioned. The new plant features algorithm-controlled processing to enable the fast and accurate introduction of new and existing generations of etchants and cleaners. A Wonderware In-Batch system was chosen as the control base for the project, for its ability to provide both flexibility and integration between highly critical recipe manufacturing, packaging and cleanroom sample analysis. It also allows simple integration with the Protean system already operating at the Riddings site. The variable fill rate elements of the In-Batch system operate via a series of Burkert process valves from Burkert Fluid Control Systems, fitted with integrated Profibus DP control heads. The valve inventory comprises Burkert 2712 stainless steel globe valves, 2731 stainless steel diaphragm valves and 2730 PVDF diaphragm valves. The process produces some 300 different chemical mixtures for use in semiconductor manufacturing.