Environmental Engineering
T. Handayani; I.N. Djarot; N. Widyastuti; F.D. Arianti; A. Rifai; A.I. Sitomurni; M.M.A. Nur; R.N. Dewi; N. Nuha; J. Haryanti; D. Pinardi; Y. Suryana; A. Aziz; E. Syamsudin; T. Rochmadi; P.A. Lomak; A. Hadi; M.D. Pertiwi; E. Yuniastuti; N.A. Putri
Abstract
BACKGROUND AND OBJECTIVES: During this energy transition, research is being done to develop sustainable ways to support the shift to a decarbonized energy and production system. These ways include using renewable energy sources to promote circularity in products, green technologies, and safer procedures. ...
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BACKGROUND AND OBJECTIVES: During this energy transition, research is being done to develop sustainable ways to support the shift to a decarbonized energy and production system. These ways include using renewable energy sources to promote circularity in products, green technologies, and safer procedures. Anaerobic digestion of palm oil mill effluent is a beneficial process for generating biogas, while the waste can also be utilized as fertilizer. The biogas can be further refined into biomethane, a valuable resource commonly used in transportation and power generation. The objective of this study is to examine the enhancement of biogas from Palm oil mill effluent and the elimination of sludge nutrients by utilizing microalgae Chlorella vulgaris. The microalgae will be cultivated in a modified photobioreactor to enhance the capture of carbon dioxide.METHODS: The study utilized anaerobic batch reactor digesters. A modified photobioreactor, consisting of two columns separated by a membrane, was developed for the technological advancement of biogas upgrading, specifically for carbon dioxide capture and biogas upgrading. A technological gap in biogas upgrade technology innovation is filled by the improved photobioreactor. To optimize the bio-fixation of carbon dioxide from flue gas, it is essential to carefully select a suitable strain of microalgae that possesses both a strong ability to absorb carbon dioxide and a high tolerance to varying concentrations of this gas. By choosing the right strain, the efficiency of carbon dioxide removal can be significantly enhanced. Since Chlorella vulgaris microalgae have demonstrated this potential, they were chosen for this investigation. Microalgae also play a role in removing nutrients contained in the sludge. FINDINGS: Numerous chemical and biological methods have been used to upgrade biogas. Results of biological upgrading of biogas from palm oil mill effluent have been reported, with carbon dioxide removal reaching 89 percent until the methane concentration of the biogas is upgraded to 84 percent. The highest biomass of 1,835 grams per liter was achieved by culturing the microalgae Chlorella vulgaris in laboratory-scale photobioreactors. In this study, the application of 15 percent volume per volume biogas with an optical density of 0.4 was found to be optimal for the growth of the microalgae. The cultivation period lasted for 14 days. The peak biomass production was observed due to the achievement of a remarkable 98 volume per volume efficiency in carbon dioxide removal, which subsequently led to a significant rise in methane content, reaching 60 percent. The enhanced biogas achieved a peak methane content of 98 percent, indicating a significant improvement in quality.CONCLUSION: The findings of this study, conducted using a modified photobioreactor, indicate that Chlorella vulgaris demonstrated high efficacy in the removal of carbon dioxide, with a rate of up to 90 percent. Additionally, it exhibited remarkable performance in upgrading biogas derived from palm oil mill effluent, achieving a conversion rate of up to 98 percent. The optical density of microalgae at 0.4 played a crucial role in these processes. Furthermore, Chlorella vulgaris showcased its ability to effectively eliminate nutrient nitrogen, reaching a removal rate of 90 percent at an optical density of 0.2. Moreover, it demonstrated a phosphate removal rate of 80 percent at an optical density of 0.4.
Environmental Engineering
P. Periadnadi; N. Nurmiati; F.W. Siregar; T.W. Edelwis
Abstract
BACKGROUND AND OBJECTIVES: Lipid-degrading bacteria found in processing ponds of palm oil mill effluent are recognized for the capacity to break down lipid using lipase enzyme. Identifying novel strains of these bacteria with high bioremediation potential contributes valuable insights to the sustainable ...
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BACKGROUND AND OBJECTIVES: Lipid-degrading bacteria found in processing ponds of palm oil mill effluent are recognized for the capacity to break down lipid using lipase enzyme. Identifying novel strains of these bacteria with high bioremediation potential contributes valuable insights to the sustainable management of palm oil mill effluent. Therefore, this study aimed to identify potential bacteria, assess the in vitro lipid-degrading capabilities, characterize the traits, and evaluate lipid degradation activity of potential isolates from palm oil industry wastewater.METHODS: The method used for exploring the potential of lipid-degrading bacteria in palm oil mill effluent entailed a survey comprising various stages including detection of bacteria presence, in vitro assessment of potential indices, characterization, lipid degradation testing, and determination of lipase activity.FINDINGS: The results showed that several bacteria groups were present in palm oil mill effluent, including 50-74 percent lipolytic, 31-90 percent fermentative, 76-83 percent proteolytic, and 51-74 percent cellulolytic. Selected lipid-degrading isolates demonstrated significant in vitro potential, as evidenced by high lipolytic and fermentative indices. Isolate Enzymatic 3 had the highest lipolytic index, degradation value (48.72 percent), and lipase activity (0.12 units/milliliter), identified as Bacillus cereus central carbon metabolism 2010. Similarly, isolate Fermentative 2 was found to have the highest fermentative index, degradation value (22.35 percent), and lipase activity (0.01 units/milliliter), identified as Bacillus thuringiensis American type culture collection 10792.CONCLUSION: Based on the results, isolates Enzymatic 3 and Fermentative 2 showed promising potential as biological agents for bioremediation of palm oil mill effluent. The results underscored the promising potential of specific bacteria isolates in mitigating lipid-rich effluents, advocating for the integration into sustainable wastewater management practices in palm oil industry. This study provided valuable insights for future investigations aimed at unraveling the intricate mechanisms governing lipid degradation and fostering environmentally friendly solutions for industrial waste management.
Environmental Engineering
A. D. Santoso; T. Handayani; D. Pinardi; K. Kusrestuwardani; N. Widyastuti; I. N. Djarot; J. Haryanti; A. I. Sitomurni; H. Apriyanto
Abstract
BACKGROUND AND OBJECTIVES: Palm oil mill effluent is a liquid waste produced at a palm oil mill industry during the production process containing abundant organic pollutants such as nitrogen and phosphorus that will be harmful to the environment. However, palm oil mill effluent as a nutrient for the ...
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BACKGROUND AND OBJECTIVES: Palm oil mill effluent is a liquid waste produced at a palm oil mill industry during the production process containing abundant organic pollutants such as nitrogen and phosphorus that will be harmful to the environment. However, palm oil mill effluent as a nutrient for the growth of microalgae has the potential for pollutant removal as well as algae biorefinery products such as biofuel, functional food and many others. This research objectives to analyze the sustainability of the microalgae biomass production for bio-refinery based on the sustainability index assessment. METHODS: The primary data was compilated via the questionnaires to researchers in the community of microalgae as well as scientific judgment by experts as respondents. Data is processed and analyzed using the multidimensional scaling Rapfish program. Data analyzed was conducted by analyzing four dimensions: social, economic, ecological, and technological dimensions which consisting of 47 attributes.FINDINGS: The result showed that the sustainability index calculated was 73.53 percent (good), which indicates the process has the potential to be developed while paying attention to leverage factors in every dimension of the sector. Analysis of each dimension on the 4 dimensions shows that the environment dimension is lowest in 67.30 percent, while the economy, technology and social dimension are 70.99 percent, 73.67 percent and 82.17 percent, respectively. Some leverage attributes that require more attention in order to improve sustainability are management experience and skills (in environment dimension), involvement of family member (in the social dimension), the productivity level (in economic dimension), and management of experience and skill (technological dimention).CONCLUSION: Based on the prospective analysis, it is known that there are 4 key factors or dominant factors that are very influential in the microalgae supply system, namely production, productivity, land conversion, consumption per capita and population. It is still necessary to do further research for the utilization of microalgae biomass into value-added products with an optimal, technically, economically, environmentally and socially sustainable system. The study provides insights on the feasibility of the proposed sustainable concept in Indonesia for the government to arrange policies and programs.
