Development of an operational manual for color reduction in coffee processing from Universal Robina Corporation by activated-carbon adsorption method

• Main Author: Frias, Noli Adavan
• Format: text
• Language: English
• Published: Animo Repository 2011
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/4082
• Institution: De La Salle University

This paper describes the practicum project accomplished at the Universal Robina Corporation San Pedro Plant. The project focuses on the development of an operational manual for color reduction in coffee processing by activated carbon adsorption method. Dark color in coffee wastewater is brought about by a persistent pigment called coffee brew melanoidin which forms during roasting of coffee beans. The company has been challenged in meeting the effluent standards set by the Department of Environment and Natural Resources (DENR). The effluent at the end of the pipe treatment is discharged into Laguna De Bay, classified as Class C. The average concentration of color that comes out of the existing wastewater facility is 2,000 PCU but the effluent standard set by DENR 150 PCU. This study involved adsorption test by contacting coffee wastewater obtained from the effluent coffee wastewater sample of Universal Robina Corporation (URC) in San Pedro Plant with a granular activated carbon sourced from Industry Technology Development Institute (ITDI) in a beaker set-up. The process parameters such as carbon loading or amount of AC per volume of the sample, initial pH of the sample and residence time were varied to establish the optimum conditions. Absorbance was measured using UV-VIS Spectrophotometer. Optimum conditions were obtained at carbon loading of 40g/L, pH 4 and residence time of 15 min to which 68.69 % color reduction was achieved; a 3-series downflow activated carbon column was proposed to bring down the color concentration to 76.66 PCU. The saturation point of activated carbon averaged 4g/L as obtained from batch tests. The equilibrium study showed that melanoidin adsorption on AC followed Freundlich isotherm and the maximum adsorption capacity was found to be 2.47 % transmittance L/g adsorbent. Moreover, the practicum covered also the monthly monitoring of effluent parameters. It was observed that amongst the processes in the coffee manufacturing, percolation generated the highest volume of wastewater (33.06%), generated at 4 m3/hr. By and large, application of AC adsorption process in treating the color issue in the effluent would definitely enable the company to meet the color standard.