APPLICATION OF ALUM PLANT WASTE LIQUOR IN TREATMENT OF ALKALINE WASTEWATERS

The presence of acidity and dissolved aluminium in the alum plant wast e liquor has been used in the treatment of wastewaters of alkaline nat ure. The wastewaters from soap plant, textile milt copper ore-concentr ate and milk processing plant were made to interact with the alum plan t liquor in such volume ratios as to produce equilibrium pH of 7. Para llel runs to produce equilibrium pH 6 of the resulting mixtures were a lso carried out. The percentages of removal of TDS and COD of the inte raction fluids at the pH 7 were found to be 95.0 and 97.5, respectivel y, for interaction with the soap plant wastewaters, 82.3 and 93.2 with the textile wastewaters 75.5 and 92.3 with copper ore wastewaters, an d 60.9 and 94.4 with milk processing wastewaters. There was also signi ficant lowering in the values of ionic species. Compared to the intera ction at the equilibrium pH of 6, that at the equilibrium pH of 7 was found to give a higher degree of removal of the pollutional characteri stics of the wastewaters.