Effective Removal of Moisture and Ash from Coal Tar

The influence of oxyethylated alkyl phenol (Neonol AF9–10) on the clarification of coal tar in mechanized settling tanks is considered. Adding Neonol is found to increase the deposition rate of tar sludge. If Neonol is present in the wastewater sent to the biochemical treatment plant, its operation is not significantly affected. The use of Neonol in the separation of water–tar mixtures decreases the content of tarry impurities. Ash removal from tar in mechanized settling tanks may be intensified by adding Neonol, with decrease in the rate at which sediment builds up in tar stores. The stability of water–tar emulsions declines on adding Neonol. On the basis of these results, the use of Neonol may be recommended to stabilize the quality of coal tar.