Abstract

Effect of the chemical dosing in primary treatment study of the textile based industrial waste water

Author(s): Anil Choudhary, Deepak Ojha

Waste water from textile industries has a high PH, high temperature and a high concentration of organic materials. Removing Colour and organics fromwaste water is more important because the presence of small amounts of dyes is clearly visible and detrimentally affects into the water quality. In primary treatment process of textile based effluent, simple chemicals such as lime (10%sol.), iron salts (5%sol.), polyelectrolyte (0.1%sol.) gave good result and removed Colour,COD,BOD,TSS faster than physical processes. The analysis results according to Jar-test were depicted in the stage-wise performance of inlet and outlet effluent quality in ETP. In primary treatment the Colour of these effluentsmostlyRed-Black or Dark green to change into Yellow or Light Green. The Chemical Oxygen Demand are 60% decrease, Total Suspended Solids 50% decrease, Hardness 20% decrease but Total Dissolve Solids ˜ 32% increase due to addition of Lime solution. The flock Produced by iron salt with lime at pH 10 to 11is heavier and can remove more percentage of Suspended Solids than Alum in a very short time period. Iron salt (ferrous sulphate and ferric sulphate) makes 90% treated water and 10%sludge. The Sedimentation of Sludge is very fast by Iron salt thanAlum. Being good oxidizing agents, the Iron salts can remove Hydrogen sulphide, hydrogen sulphate and its corresponding Odour and tastes fromwater.