Aggregation of inherently hydrophobic solids using hydrophobic agglomerants and flocculants

摘要

Aggregation of fine suspensions of coal and molybdenite with the use of polyacrylamide type flocculants, latex type hydrophobic agglomerants, and emulsified oil have been tested. Size enlargement of particles is a frequent aid to solid/liquid separation unit operations (settling and filtration). Our tests were focused not only on the size enlargement, but also on the surface properties of the aggregates which were shown to be very important in flotation and filtration. The results have revealed that the UBC-1 hydrophobic latex is highly selective and agglomerates only hydrophobic particles, while polyacrylamides flocculate all particles irrespective of their wettability. The aggregates obtained when using hydrophobic agglomerants are hydrophobic and so the use of such additives improves flotation, and not only improves filtration rate but also reduces the cake moisture content Based on the discussed results, the classification of aggregating additives that takes account of solid wettability, hydrophobicity of aggregates, and their effect on other unit operations in the same water circuit is put forward.