Karakterisasi Pertumbuhan Mikroalga dan Penyisihan Nutrien dari Limbah Cair Rumah Pemotongan Hewan dengan Sistem Kultur Semi Kontinu

Abstract

Organic wastewater with high nutrient content can stimulate uncontrolled microalgae growth. Whereas discipline control led growth can be very profitable. The research was performed to determine the characteristic of growth microalgae nutrient elimination from slaughterhouse wastewater in semi continuous culture system with 75% concentration of slaughterhouse wastewater : 25% consortium of microalgae. In addition, the separation and harvesting of microalgae for the known oil content was also investigated. Cultivation of microalgae has been done at a temperature and pH of the field approach, then temperature and pH dependent on state in the field daily. The light source is obtained directly from the sun. Circulation in a semi continuous culture media which have been made simply by aeration when sampling. Microalgae consortium cell density attained 640 000 cell/ml. During the cultivation for 18 days, the growth of Chlorella sp dominate the culture, that follow by growth of Euglena on day 20 after the death phase of Chlorella sp through. The best growth of Chlorella sp (on day-12) occurred with a concentration of nutrients containing: 1 mg/l for N-organic content, 1 mg/l for NNH3, 4 mg/l for N-NO3 - then total of nitrogen 6 mg/l, orthophosphate content of 10 mg/l, and potassium values of 87.5 mg/l with consortium cell density attained 3 130 000 cell/ml and TSS Filtration 1 930 mg/l. Convertion of biomass from TSS with amount of nitrogen or TKN (on day 2 until 12) is 180 mg TSS/ mg TKN and convertion of biomass from TSS with orthophosphate content in the same time is 4 200 mg TSS/ mg Orthophosphate. Maximum population of microalgae decrease due to lower nutrient content in culture media. Although the consortium of microalgae dominated by Chlorella sp, oil content (3.03%) and oil productivity is 3 000 liter/ha/year still low compared with a previous study, that have been in research by Hsieh and Wu (2009), Widjaja (2009) along with Danusubrata (2010). It was caused by nutrient treatment which have not yet optimum.