Improvement of paint effluents coagulation using natural and synthetic coagulant aids

J Hazard Mater. 2006 Nov 2;138(1):40-5. doi: 10.1016/j.jhazmat.2006.05.040. Epub 2006 May 20.

Abstract

The coagulant iron chloride and the flocculants Polysep 3000 (PO), Superfloc A-1820 (SU) and Praestol 2515 TR (PR) have been used in this study to show the efficiency of coagulation flocculation process in the chemical precipitation method for the removal of organic and colouring matters from the paint industry wastewater. This study also includes the amount of produced sludge. The results indicate that FeCl(3) is efficient at pH range 8-9 and at optimal dose of 650 mgl(-1). Iron chloride allows the removal of 82% of chemical oxygen demand (COD) and 94% of colour. However, sequential addition of coagulant and polymeric additives enhance clearly pollutant removal and produces less decanted sludge compared to the results obtained when the coagulant is used alone. The removal efficiency of COD reaches 91% and that of colour 99%. Coagulation-biflocculation process is more effective than the coagulation-monoflocculation one. The sequential addition of iron chloride, Polysep 3000 (cationic flocculant) and Praestol 2515 TR (anionic flocculant) seems to be the most suitable combination for the treatment of the paint industry wastewaters.

Publication types

  • Comparative Study

MeSH terms

  • Chlorides
  • Coloring Agents / chemistry
  • Coloring Agents / isolation & purification
  • Dose-Response Relationship, Drug
  • Ferric Compounds / chemistry*
  • Flocculation
  • Hydrogen-Ion Concentration
  • Industrial Waste*
  • Ions
  • Oxygen / chemistry
  • Oxygen / isolation & purification
  • Oxygen / metabolism
  • Paint*
  • Polymers / chemistry*
  • Sewage / chemistry
  • Time Factors
  • Waste Disposal, Fluid / methods*
  • Water Pollutants, Chemical / chemistry
  • Water Pollutants, Chemical / isolation & purification*

Substances

  • Chlorides
  • Coloring Agents
  • Ferric Compounds
  • Industrial Waste
  • Ions
  • Polymers
  • Sewage
  • Water Pollutants, Chemical
  • Oxygen
  • ferric chloride