Produksi spirulina untuk penurunan tingkat cemaran limbah cair pabrik kelapa sawit dalam fotobioreaktor kontinyu

Abstract

Spirulina platensis could be grown on Palm Oil Mill Effluent (POME) to produce algal biomass and to reduce pollution level of the effluent. The objective of this research was to determine the growth rate of S. platensis and the reduction rate of pollution level of POME on semi-continuous photobioreactor. Preliminary research was conducted by growing S. platensis on POME media with various concentration, namely 25%, 50%, 75%, and 90% POME by batch system. Results of the preliminary research could be used to obtain the optimum growth period as a reference for the main research. The main research on the growth of S. platensis was conducted on photobioreactor that adjusted with their feeding rate of media containing a mixtime of POME and synthetic media at optimum concentration. Feeding rate was set up at 1 drop/ 5 sec. (dilution rate of 0.03 hr -1), 1 drop/ 10 sec. (dilution rate of 0.015 hr -1), and 1 drop/ 15 sec. (dilution rate of 0.01 hr -1). The main research was conducted with 1.2 liter-capacity photobioreactor with POME media at optimum concentration after optimum growth. For optimum dilution rate, the experiment was scaled up eight times using 10-liter-capacity photobioreactor. The parameter observed was Total Dissolved Solid (TDS), Fixed Dissolved Solid (FDS), Volatile Dissolved Solid as approximate value of Total Carbon (TC), Optical Density (OD) at λ 480 nm (OD 480 nm), Dissolved Oxygen (DO), Biological Oxygen Demand (BOD), and Chemical Oxygen Demand (COD).