text: The main advantage over other filtration systems is the reduction in energy consumption, up to 90% because no air flows through the discs due to the use of capillary force acting on the pores. Air breakthrough is prevented by the fine pores of the filter, thus allowing retention of higher vacuum levels. Therefore, the vacuum losses are less, which means the vacuum pump required is smaller than in conventional disc filters, thus minimizing operating costs. Power consumed by a vacuum ceramic filter with 45 m of filtration area is 15 kW while 170 kW is consumed by similar filters with cloth membranes.
  Generally, conventional disc filters are not suitable for cake washing because the water quickly runs off the surface of the cake. As the cake solids are sprayed with a wash liquid to remove impurities, they are not suitable for conventional filtration systems where channelling or uneven distribution occurs, leading to cake cracking. However, cake washing has been proved to be more efficient with vacuum ceramic filters due to the steady flow profile and the even distribution of the cake.
  A further advantage of vacuum ceramic filter is the high output capacity with a very low water content and drier filter cake. By comparison, the performance of a VDFK-3 ceramic filter was compared with the existing BOU-40 and BLN40-3 drum type vacuum filters to filter aluminium hydroxide. From the results, the average moisture content was 5% (abs? or rel?) lower when a vacuum ceramic filter was used.
  Vacuum ceramic filters also have a longer service life while cloth filters have to be replaced, which eventually increases the moisture content of the cake, lowers the productivity and disturbs the production operations.  In addition, the ceramic filter is both mechanically and chemically reliable enough to withstand regeneration.
  Whilst the vacuum ceramic filter has proved to be a great innovation, there are still some limitations involved when operating the equipment. Ceramic filters exhibit large fluctuations in the recoiling washing pressure (0.05~0.35 MPa). This raises the short-term negative pressure and induces dilute acid due to the falling suck phenomenon. Therefore, the cleaning effect of the ceramic plates and the efficiency of the filter will be negatively affected.