ECONOMIC COMPARATIVE EVALUATION OF COMBINATION OF ACTIVATED CARBON GENERATION AND SPENT ACTIVATED CARBON REGENERATION PLANTS

Abstract

The purpose of this study was to investigate the maximum annual profit of proposed three project plants as follows: (i) a generation process of activated carbon (AC) prepared from coconut shells; (ii) a regeneration process of spent AC obtained from petrochemical industries; and (iii) a project combined the AC generation process with the regeneration process. The maximum annual profit obtained from the sole regeneration plant was about 1.2- and 15.4- fold higher than that obtained from the integrated and the generation plants, respectively. The sensitivity of selected variables to net present value (NPV), AC sales price was the most sensitive to NPV while fixed costs of generation and regeneration, and variable cost of regeneration were the least sensitive to NPV. Based on the optimal results of each project plant, the economic indicators namely NPV, return on investment (ROI), internal rate of return (IRR), and simple payback period (SPP) were determined. Applying a rule of thumb of 12% IRR and 7-year SPP, the AC sales prices for the generation, regeneration, and integrated plants were 674.31, 514.66 and 536.66 USD/ton of product, respectively. The economic analysis suggested that the sole regeneration project yields more profitable.

Keywords

• Activated carbon
• Generation plant
• Profit optimization
• Regeneration plant
• Spent activated carbon.