Adsorption and Microfiltration Processes to Treat Dye and Coffee Wastewater.

Wastewater from coffee processing industry creates high biological and chemical oxygen demand in the surface water. In addition to coffee wastewater from coffee industry, dyes from textile industry enter surface water affecting water quality in terms of transmissivity of light. Adsorption is an economical wastewater treatment process to remove color from dye and coffee wastewater. In the current thesis, adsorption using low-cost adsorbents like peanut hull and onion peel are used to treat combined dye and coffee wastewater. Three representative dyes including acid black 48, disperse yellow 3, crystal violet certified with processed coffee is used in preparing batch adsorption samples. Using UV-Vis Spectrophotometer, absorbance and transmittance of the wastewater samples are measured. After adsorbents reach adsorption capacity, the suspended solids are removed using Whatman 41 microfilters. To understand the change in organic carbon before and after treatment in the wastewater, NPOC (Non-Purgeable Organic Carbon) is compared using Shimadzu TOC analyzer. This thesis focuses on the two-stage treatment process of adsorption and microfiltration in a binary mixture of dye and coffee wastewater. Increasing Adsorbent dosage in the representative wastewater samples gives us the idea of optimum dosage required in the treatment process. The comparative study of adsorbent dosage with transmittance and NPOC gives us an understanding of the efficiency of low-cost adsorbents when compared to Powdered Activated Carbon