Multistage Ozone Treatment of Dye Waste

Abstract

An ozonation technology to treat lightly loaded effluents from dye manufacturing processes has been developed. The process uses airgenerated ozone and countercurrent contactors. An intermediate step is included to eliminate OH-radical scavengers and slowly reacting oxidized species from the liquid phase.

A study of ozone efficiency and yield concerning the reduction of TOC and COD levels is presented. The biological degradability.of treated water is discussed. A design and rating calculation procedure for countercurrent contactors is presented. Various waste treatment strategies using separation processes and ozone are discussed briefly. A cost estimate to treat a typical dye effluent in two stages on industrial scale is included.

Keywords:

• Ozone
• Dye Waste Treatment
• Multi-Stage Ozonation
• Countercurrent Ozone Contacting
• Costs of Ozone Treatment