Evaluating Biogas Production of Polylactic acid with the addition of Conductive Materials
Objectives The demand for polylactic acid (PLA) is increasing as an alternative to conventional petroleum-based plastics due to its eco-friendly characteristics. PLA can be processed through anaerobic digestion (AD) along with other organic wastes to promote efficient and controlled biodegradation....
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| Format: | Article |
| Language: | English |
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Korean Society of Environmental Engineers
2023-10-01
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| Series: | 대한환경공학회지 |
| Subjects: | |
| Online Access: | http://www.jksee.or.kr/upload/pdf/KSEE-2023-45-10-409.pdf |
| _version_ | 1797397505200095232 |
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| author | Jung-Sup Lee Tae-Hoon Kim Yeo-Myeong Yun |
| author_facet | Jung-Sup Lee Tae-Hoon Kim Yeo-Myeong Yun |
| author_sort | Jung-Sup Lee |
| collection | DOAJ |
| description | Objectives The demand for polylactic acid (PLA) is increasing as an alternative to conventional petroleum-based plastics due to its eco-friendly characteristics. PLA can be processed through anaerobic digestion (AD) along with other organic wastes to promote efficient and controlled biodegradation. This study aimed to evaluate the feasibility of biogas production through AD of PLA and to enhance efficiency through the addition of conductive materials. Methods Two sets of biochemical methane potential (BMP) tests were conducted. The first BMP test involved substrate/inoculum ratios (SIRs) of 0.6, 0.8, 1.0, 1.2, 1.4, and 1.6 (g COD PLA/g COD seed sludge). Conductive materials powdered activated carbon (PAC), carbon nanotube (CNT), and Magnetite were individually added to reactors at a concentration of 3 g/L in the second test. Results and Discussion The study revealed an increasing trend in methane production and methane yield with higher levels of PLA input. However, a decline in methane yield was observed when PLA was injected at levels surpassing 35g COD/L. This phenomenon can be attributed to a prolonged Lag phase, indicating a longer adaptation period for microorganisms, consequently resulting in a reduction of the conversion rate from 1g COD substrate to methane. The introduction of conductive material led to elevated cumulative methane production and methane yield in comparison to the control group. Notably, Magnetite exhibited the highest increase rate among the tested materials. Additionally, the addition of PAC demonstrated favorable results in terms of methane production rate at 99.4mL/L/Day and a Lag phase of 5.7 days. Conclusion Experiments were conducted to evaluate the effects of PLA biogas production and the injection of PAC, CNT, and Magnetite at various substrate/inoculum ratios. When PLA was used as a substrate for anaerobic digestion, its feasibility was confirmed. However, it exhibited lower efficiency compared to other substrates. Therefore, the addition of a conductive material was found to increase the biogas production efficiency. |
| first_indexed | 2024-03-09T01:10:59Z |
| format | Article |
| id | doaj.art-c94d7021c3454acaaec7df4448d5d57d |
| institution | Directory Open Access Journal |
| issn | 1225-5025 2383-7810 |
| language | English |
| last_indexed | 2024-03-09T01:10:59Z |
| publishDate | 2023-10-01 |
| publisher | Korean Society of Environmental Engineers |
| record_format | Article |
| series | 대한환경공학회지 |
| spelling | doaj.art-c94d7021c3454acaaec7df4448d5d57d2023-12-11T06:32:49ZengKorean Society of Environmental Engineers대한환경공학회지1225-50252383-78102023-10-01451040941510.4491/KSEE.2023.45.10.4094475Evaluating Biogas Production of Polylactic acid with the addition of Conductive MaterialsJung-Sup Lee0Tae-Hoon Kim1Yeo-Myeong Yun2Department of Environmental Engineering, Chungbuk National University, Republic of KoreaDepartment of Environmental Engineering, Chungbuk National University, Republic of KoreaDepartment of Environmental Engineering, Chungbuk National University, Republic of KoreaObjectives The demand for polylactic acid (PLA) is increasing as an alternative to conventional petroleum-based plastics due to its eco-friendly characteristics. PLA can be processed through anaerobic digestion (AD) along with other organic wastes to promote efficient and controlled biodegradation. This study aimed to evaluate the feasibility of biogas production through AD of PLA and to enhance efficiency through the addition of conductive materials. Methods Two sets of biochemical methane potential (BMP) tests were conducted. The first BMP test involved substrate/inoculum ratios (SIRs) of 0.6, 0.8, 1.0, 1.2, 1.4, and 1.6 (g COD PLA/g COD seed sludge). Conductive materials powdered activated carbon (PAC), carbon nanotube (CNT), and Magnetite were individually added to reactors at a concentration of 3 g/L in the second test. Results and Discussion The study revealed an increasing trend in methane production and methane yield with higher levels of PLA input. However, a decline in methane yield was observed when PLA was injected at levels surpassing 35g COD/L. This phenomenon can be attributed to a prolonged Lag phase, indicating a longer adaptation period for microorganisms, consequently resulting in a reduction of the conversion rate from 1g COD substrate to methane. The introduction of conductive material led to elevated cumulative methane production and methane yield in comparison to the control group. Notably, Magnetite exhibited the highest increase rate among the tested materials. Additionally, the addition of PAC demonstrated favorable results in terms of methane production rate at 99.4mL/L/Day and a Lag phase of 5.7 days. Conclusion Experiments were conducted to evaluate the effects of PLA biogas production and the injection of PAC, CNT, and Magnetite at various substrate/inoculum ratios. When PLA was used as a substrate for anaerobic digestion, its feasibility was confirmed. However, it exhibited lower efficiency compared to other substrates. Therefore, the addition of a conductive material was found to increase the biogas production efficiency.http://www.jksee.or.kr/upload/pdf/KSEE-2023-45-10-409.pdfbiogasbioplasticconductive materialanaerobic digestionpla |
| spellingShingle | Jung-Sup Lee Tae-Hoon Kim Yeo-Myeong Yun Evaluating Biogas Production of Polylactic acid with the addition of Conductive Materials 대한환경공학회지 biogas bioplastic conductive material anaerobic digestion pla |
| title | Evaluating Biogas Production of Polylactic acid with the addition of Conductive Materials |
| title_full | Evaluating Biogas Production of Polylactic acid with the addition of Conductive Materials |
| title_fullStr | Evaluating Biogas Production of Polylactic acid with the addition of Conductive Materials |
| title_full_unstemmed | Evaluating Biogas Production of Polylactic acid with the addition of Conductive Materials |
| title_short | Evaluating Biogas Production of Polylactic acid with the addition of Conductive Materials |
| title_sort | evaluating biogas production of polylactic acid with the addition of conductive materials |
| topic | biogas bioplastic conductive material anaerobic digestion pla |
| url | http://www.jksee.or.kr/upload/pdf/KSEE-2023-45-10-409.pdf |
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