Bioelectricity production from Tofu wastewater using microbial-microalgae fuel cell technology (MMFC)

Abstract

Tofu industries have been known as one of the household industries that spread all over cities in Indonesia, and that makes the significant amount of wastewater. Tofu wastewater contains a high measure of COD that can cause environmental damage if it doesn't reduce before flowing on the waterways. In this study, explains the COD reduction of wastewater from the tofu industry for electricity generation and biomass production of microalgae Spirulina Platensis within Microalgae-Microbial Fuel Cell (MMFC). Anaerobic microbes in tofu wastewater were used in the anode chamber and produced electron. Spirulina platensis culture in cathode chamber produced oxygen for the Oxygen Reduction Reaction by carbon-based electrode such as graphite. The result of this study showed that MMFC could generate electricity up to 171,44 mW.m-2 when two pieces of graphite electrode were adopt in the system with a membrane surface area was 2.85 cm2. The OD spirulina achieved 0,513 on day 7. The COD removal achieved 42% for ratio 2:2 cathode when applied in the MMFC system.