SUMMARYAn experimental apparatus combining the principles of mechatronics with a dead-end pressure leaf filter is described. The computer controlled and sequenced apparatus was used to monitor performance during the cake formation, gas dewatering and displacement washing phases of filter cycles. Data relating to cake properties and liquor transport rates were acquired through electrical resistance measurements and suitable transducers. The data illustrate the versatility and accuracy of the apparatus and they are used to compare with predictions given by existing theories, particularly for cake formation. Batch experimental results obtained with aqueous suspensions of calcite are shown to compare favourably with theoretical predictions for important design parameters such as cake height and cumulative volume of filtrate whereas data for more compressible talc systems tended to show more deviation. The work presented highlights the benefit of a mechatronics approach to experimentation and emphasises the importance of data acquisition and system control to future developments in filter design.

SUMMARYAn experimental rig capable of automatically sequencing and collecting data from a deadend pressure filter is described. The computer controlled apparatus uses electrical impedance measurements in multiple vertical scanning planes to determine the status of a filter cake during either the cake formation, gas dewatering or displacement washing phases of a filter cycle. The data acquired are displayed in real time during a test in conjunction with an indication of liquor flow rates. Initial results from an experimental programme are presented which show the filtration and dewatering characteristics of aqueous based calcium carbonate suspensions. The importance of data acquisition and system control are discussed and an outline of future developments is given.

SUMMARYA mechatronics approach has been employed to improve the performance of a solid-liquid separation device. The basic principles of the 'chematronics' task are described with reference to a computer controlled, pilot scale, pressure leaf filtration rig capable of measuring in-situ solids concentration profiles. By combining suitable sensors, transducers and control software it is shown how data can be acquired to correctly control and monitor all aspects of the filter cycle and yield a flexible apparatus capable of operating in a number of modes.