Microalgae Microbial Fuel Cell (MMFC) using Chlorella vulgaris and Batik Wastewater as Bioelectricity
Nadiyah Faizi Polontalo (a,b), Falvocha Alifsmara Joelyna (a,b), Abdullah Malik Islam Filardli (a,b), Hadiyanto (a,b,*)
a) Chemical Engineering Department, Faculty of Engineering, Diponegoro University, Indonesia
b) Center of Biomass and Renewable Energy (C-BIORE) Diponegoro University, Indonesia
*) corresponding author: hadiyanto[at]live.undip.ac.id
Abstract
The increasing of human growth in Indonesia every year might cause the increasing demand for electricity. Electricity demand in Indonesia is estimated to continue to grow by 4.6% per year. Fossil fuel especially coal, plays an important role in electric steam power plant in Indonesia, which reaches 48% of total domestic capacity. However, the availability of coal as raw material will continue to decline because it requires a long time to be renewed. Other alternative energy is needed to fulfill the energy supply. One of the environmentally alternative energies that can be solved this problem is the microbial fuel cell (MFC) which utilizes organic matter (substrate) as an energy source of bacteria in carrying out its metabolic activities to produce electricity. This system utilizes waste water as a substrate so that it can be used as an ideal tool for electricity production. In this study, we investigated the electrical energy produced by MMFC (Microalgae Microbial Fuell Cell) using microalgae Chlorella vulgaris and batik waste (Figa Batik Collection) in Semarang. This study aims to evaluate the performance of the MMFC system based on the influence of yeast variations (8 gr/l and 2 gr/l), the concentration of batik waste (50% and 100%), and the number of graphite electrodes (1:1 and 2:2). The experiment starts from culturing Chlorella vulgaris until it has an absorbance closer to one. Then, a series of MMFC systems is carried out where the anode chamber is filled with 1 litre of batik waste and the cathode chamber is filled with 1 litre of Chlorella vulgaris. MMFC simulation is operated for 7 days, then every 24 hours the next voltage and current are measured to be processed into power density. The absorbance analysis and COD level were carried out with a spectrophotometer. The results of this study showed that the concentration of 100% batik wastewater and 2:2 bars graphite electrode was the best results in MMFC process with the highest voltage and the highest current of the run was found to be 0.108 V and 0.039 A. Besides, the addition of yeast to batik wastewater has a major influence on the results of the MMFC process. Because, yeast became a catalyst in oxidizing waste which made electron transfer more frequent.
Keywords: Batik Wastewater, Bioelectricity, Chemical Oxygen Demand, Chlorella vulgaris, Microbial Fuel Cell, Power Density
Topic: Bioenergy