The Production of Activated Carbon from Coconut Shells Using Pyrolysis and Fluidized Bed Reactors

Abstract

A production plant was designed to produce 14.5 metric tons of activated carbon per day from coconut shells, in order to capture 2% of the projected market for activated carbon in air purification applications by 2014. The production process consists of a pyrolysis stage and an activation stage. A downdraft gasifier was utilized as the pyrolysis reactor in order to maximize the energy efficiency of the process, and a separate cyclone and condenser were added to capture and purify the valuable byproducts of the pyrolysis reaction. A fluidized bed reactor was utilized as the activation reactor, due to its superior heat and mass transfer properties over conventional reactors currently used in industry. An extensive heat exchanger network was implemented to capture and recycle the heat and water produced by the activation reaction, in order to minimize the plant’s thermal and water footprint. With an interest rate of 20%, the plant is expected to have a net present value of $43.8 million at the end of its ten-year lifetime. Due to the expected high product demand and anticipated profits, construction of the plant is strongly recommended.