THE INFLUENCE OF CULTURE TYPES OF ISOLATION RESULT ON BIOFILM FORMATION AND BIOCORROSION OF ST-37 CARBON STEEL IN B30 FUEL TANKTHE INFLUENCE OF CULTURE TYPES OF ISOLATION RESULT ON BIOFILM FORMATION AND BIOCORROSION OF ST-37 CARBON STEEL IN B30 FUEL TANK

• Main Author: Ijkri Aulia, Nadia
• Format: Theses
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/64901
• Institution: Institut Teknologi Bandung

Currently, biodiesel production has a mixture of 70% diesel with 30% biodiesel or another name is Biosolar 30 (B30). The use of low concentrations of biodiesel is due to concerns because biodiesel is more susceptible to oxidation and is more corrosive than diesel. The occurrence of corrosion events is due to the activity of microorganisms (Microbial Influenced Corrosion) which have the ability to degrade hydrocarbons as a carbon source and then form biofilms. MIC is often found in storage tanks. One type of metal used in this study is carbon steel ST-37. This research was conducted to determine and analyze the effect of forced isolation from B30 and the results of direct isolation from the sludge of the B30 fuel storage tank on the formation of biofilms in the oil phase and water phase. The results of this study are the culture of forced isolation obtained in the form of a mixed culture containing a combination of gram-positive and gram-negative bacteria that can cause corrosion of carbon steel metal, while the culture resulting from direct isolation is Pseudomonas sp. which includes gram-negative bacteria which can also cause corrosion and degrade compounds in hydrocarbons. Then, the number of biofilm colonies in the oil phase and water phase in forced isolation cultures and Pseudomonas sp. more than the number of colonies in the planktonic phase. Then, the corrosion rate of Pseudomonas sp. higher than the Bushnell Haas control and forced isolation cultures. The corrosion rate produced is in the excellent category so it is still safe to use in the construction of the B30 fuel tank. When viewed from the morphological side, the more days, the coarser and thicker the biofilm produced. Not only in terms of carbon steel metal, the degradation and acid number of biodiesel in the variation of Pseudomonas sp. has a higher value than other medium variations.