Cake post-treatment processes

The term post-treatment refers to processes vdiich are used after the principal solid-liquid separation has been achieved. The final step in the latter operation is usually some type of cake filtration which will leave a cake that may be fully saturated with liquid or partially drained and it is extremely unlikely that the solids are in an acceptable condition for any subsequent operation such as thermal drying. Thus the post treatment processes are washing and deliquoring which are concerned req>ectively with removing the soluble solids from the liquid remaining in the cake and then purging the major proportion of the liquid fi om the cake pores. 

Wakeman R.J., 1979c. The performance of filtration post-treatment processes 1. The prediction and calculation of cake dewatering characteristics, Filtr. Sep., 16,655-660. 

Post-treatment of filter cakes, or settled dges, is of great importance in process indastriBS and oftoi occupi modi process time. Hie removal of residual liquid fi om packed assemblies of particles, or tiie reduction in solute contammation in the retidual liquid phase can be a dow, inefiddoit processes. The main difiSoilties arise vi4ien the material to be removed is traqiped in inaccessible parts of the d osit. 

Typical uses Batch processing of suspensions forming compressible filter cakes where dry cakes and/or efficient post-treatment are required. 

Typical uses Semi-continuous processing of solids forming compressible filter cakes that require efficient post-treatment. 

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