Effect of Photoperiodicity on Co2 Fixation by Chlorella Vulgaris Buitenzorg in Bubble Column Photobioreactor for Food Supplement Production

To reduce the level of CO2 content in air, effort on converting CO2 to useful products is required. One of thealternatives includes CO2 fixation to produce biomass using Chlorella vulgaris Buitenzorg. Chlorella vulgarisBuitenzorg is applied for production of food supplement. Chlorella vulgaris Buitenzorg is also easy to handle due to itssuperior adaptation. Currently, Chlorella vulgaris Buitenzorg has been analyzed by some experts for its cellularcomposition, its ability to produce high quality biomass and the content of essential nutrition. A series of experimentswas conducted by culturing Chlorella vulgaris Buitenzorg using Beneck medium in bubbling column photobioreactor.The main variation in this experiment was photoperiodicity, where growth of Chlorella vulgaris Buitenzorg wasexamined during photoperiodicity condition. The difference between CO2 gas concentration of inlet and outlet of thereactor during operational period, was compared to the same experiment under continuous illumination. Underphotoperiodicity of 8 and 9 h/d, the culture cell densities (N) were approximately 40 % higher than under continuousillumination. Final biomass density of Chlorella vulgaris Buitenzorg at 9 h/d illumination was 1.43 g/dm3, around 46%higher than under continuous illumination. Specific carbon dioxide transfer rate (qCO2) in photoperiodicity was 50-80%higher than under continuous illumination. These experiments showed that photoperiodicity affects the growth ofChlorella vulgaris Buitenzorg The specific growth rate (μ) by photoperiodicity was higher than that by continuousilumination while the growth period was two times longer. Based on the experiments, it can be concluded thatphotoperiodicity might save light energy consumption. The prediction of kinetic model under continuous illuminationas well as under photoperiodicity illumination showed that Haldane model became the fitted kinetic model

Biomass Production Chlorella Vulgaris Buitenzorg Using Series of Bubble Column Photo Bioreactor with a Periodic Illumination

Chlorella vulgaris Buitenzorg cultivation using three bubble column photo bioreactors arranged in series with a volume of 200 mL for 130 hours shows an increase of biomass production of Chlorella vulgaris Buitenzorg up to 1.20 times and a decrease of the ability of CO2 fixation compared to single reactor at a periodic sun illumination cycle. The operation conditions on cultivation are as following: T, 29.0oC; P,1 atm.; UG, 2.40 m/h; CO2, 10%; Benneck medium; and illumination source by Phillip Halogen Lamp 20W /12V/ 50Hz. Other research parameters such as microbial carbon dioxide transferred rate (qco2), CO2 transferred rate (CTR), energy consumption for cellular formation (Ex), and cultural bicarbonate species concentration [HCO3] also give better results on series of reactor

Biodegradation of Linear Alkyl Benzene Sulfonate by bacterial consortium

Surface active agents (surfactants) are chemical compounds which are massively used as raw material in detergent production. Synthetic type surfactants are often used because they perform better and are more economical compared to natural detergents. Linear Alkyl Benzene Sulfonate (LAS) is one of the synthetic surfactants that is widely used. Although LAS is biodegradable, its introduction to the environment in big amounts harms water bodies. Research on biodegradation of LAS with 100 ppm, 400 ppm, 700 ppm, 1000 ppm and 1500 ppm concentrations was conducted by using consortium of bacteria comprising of Pseudomonas aeroginosa, Bacillus subtilis, Bacillus aglomerans, Bacillus cereus, Bacillus alvae. Experiments were carried out for twelve days, at 29oC with initial total inoculum of bacteria at 1,59 x 108 CFU/mL. Results showed that this type of bacterial consortium could tolerate 1500 ppm in LAS environment. However, significant growth rate did not occurr, 0.039 – 0.042 hour -1 and not too efficiently reduce Chemical Oxygen Demand (COD) for those systems. Surface tension in several variated concentration of LAS: 0 ppm >100 ppm >400 ppm >700 ppm, LAS 700 ppm = 1000 ppm = 1500 ppm