Chlorophyll changes during anaerobic digestion of cabbage waste

ABSTRACT

To study the changes in the contents of chlorophyll a and chlorophyll b in cabbage waste during anaerobic digestion, two types of leafy cabbage waste were treated by fermentation, and the relationship between the degradation of chlorophyll a and chlorophyll b in cabbage waste and gas production potential during anaerobic digestion was analyzed using an anaerobic batch fermentation unit maintained at a constant temperature of (35 ± 1) °C. The results showed that, following anaerobic digestion, the gas production rates of common cabbage, Chinese cabbage, and mixed cabbage were 36 mL/g, 33 mL/g, and 27 mL/g, respectively. The total solids (TS) gas production rates were 838 mL/g, 774 mL/g, and 549 mL/g, respectively, whereas the volatile solids (VS) gas production rates were 1061 mL/g, 1134 mL/g, and 636 mL/g. During the biogas fermentation process, the content of chlorophyll a in each type of cabbage waste was consistently higher than that of chlorophyll b. Moreover, chlorophyll degradation correlated with daily gas production. Among the cabbage waste types analyzed, mixed cabbage had the highest chlorophyll a and chlorophyll b degradation rates of 81.71% and 99.08%, respectively, compared to that of common cabbage or Chinese cabbage alone. These findings extend the current knowledge on anaerobic fermentation treatment of cabbage waste.

KEYWORDS:

• Anaerobic digestion
• cabbage waste
• chlorophyll a
• chlorophyll b
• chlorophyll degradation
• gas production potential

Disclosure statement

No potential conflict of interest was reported by the author(s).

Authors’ contributions

All authors contributed to the study conception and design. Dandan Wei: Conceptualization, Methodology, Writing - original draft, Writing - review & editing, Resources. Jianfeng Liu: Data curation. Chengjie Deng: Formal analysis. Changmei Wang: Software. Xingling Zhao: Investigation. Kai Wu: Investigation. FangYin: Supervision. BinYang: Visualization. Wudi Zhang: Conceptualization, Methodology, Writing - review & editing, Project administration, Funding acquisition. Material preparation, data collection and analysis were performed by Dandan Wei, Wudi Zhang and Jianfeng Liu. The first draft of the manuscript was written by Dandan Wei and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Availability of data and materials

The datasets used or analyzed during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

We would like to thank the following funding agencies for their generous grants that funded this study: Yunnan Ten Thousand Talents Plan Industrial Technology Champion Project [20191096], and Science and Technology Develop Project of Jilin Province [20200402099NC and 20200403010SF], Biogas Engineering and Resource Utilization Model Innovation Studio, Yunnan Biogas Engineering Technology Research Center, Yunnan International Science and technology cooperation project [202003AF140001].

Notes on contributors

Dandan Wei

Dandan Wei (1995), a master's student in the school of energy and environment, Yunnan Normal University, focuses on biomass energy, mainly on the treatment of vegetable waste, and has published many excellent articles in this regard. Email: [email protected].

Jianfeng Liu

Jianfeng Liu (1990), a doctoral candidate in the school of energy and environment, Yunnan Normal University, focuses on biomass energy, mainly on sewage treatment. He has published many excellent articles in this regard. He has participated in many competitions and achieved excellent results. Email: Jianfeng_ liu_ [email protected].

Chengjie Deng

Chengjie Deng (1983), the person in charge of Yunnan Yuxi Baoyu Co., Ltd., who has achieved better results in vegetable waste treatment. Email: [email protected].

Changmei Wang

Changmei Wang (1975), lecturer / Master supervisor of School of energy and Environmental Sciences, Yunnan Normal University, engaged in biomass energy research and environmental engineering teaching research,Email: [email protected].

Xingling Zhao

Xingling Zhao (1980), doctoral candidate, School of energy and environment, Yunnan Normal University, mainly engaged in anaerobic digestion of corn straw and achieved excellent results.

Wu Kai

Kai Wu (1988), lecturer / Master supervisor of School of energy and Environmental Sciences, Yunnan Normal University, engaged in biomass energy research and environmental engineering teaching and research, with deep attainments in microbiology. Email: [email protected]

Yin Fang

Fang Yin (1967), Researcher / doctoral supervisor of School of energy and Environmental Sciences, Yunnan Normal University, engaged in teaching and Research on biomass energy and environmental engineering in Chenggong campus, Yunnan Normal University, wujiaying street, Chenggong District, Kunming City, Yunnan Province, and is more professional in alcohol anaerobic fermentation. Email: [email protected].

Bin Yang

Bin Yang (1983), lecturer / Master supervisor of School of energy and Environmental Sciences, Yunnan Normal University, engaged in biomass energy research and environmental engineering teaching and research, and published many articles on anaerobic digestion of pig manure. Email: [email protected]

Zhang Wudi

Wudi Zhang (1965), corresponding author, Professor / doctoral supervisor of School of energy and Environmental Sciences, Yunnan Normal University, engaged in teaching and Research on biomass energy and environmental engineering in Chenggong campus, Yunnan Normal University, wujiaying street, Chenggong District, Kunming City, Yunnan Province. He is an expert in the field of biogas fermentation. Email: [email protected].