Transformer Oil Purification by Bleaching Clay

During transformer oil purification, not only adsorption, but also other processes such as capillary condensation, chemisorption, flocculation, coagulation have a great impact on the final product.

Very often, so-called Fuller’s earth or Fuller’s Earth filters are used as bleaching clay.  Sorbents, applied for transformer oil reclamation,  should meet the following requirements:

(1) silic acid content in the dry product no less than 32.5%; content of calcium and magnesium no more than 2.2%;

(2) the packed density of grit is no more than 0.65 g/cm3;

(3) the acid number of waste oil should be reduced by 45% per day;

(4) the size of grit grains is 3-7 mm;

(5) no more than 5% of grit grains with the size less than 3 mm;

(6) no other impurities; and

(7) moisture content is no more than 10%;

Bleaching clays may be used both for continuous oil regeneration in transformers with a dehydrating filter breather and for the restoration of oil discharged from power equipment (contact method).


Deje su mensaje