Advances in Environmental Technology

Advances in Environmental Technology

Advances in biogas production technologies: Feedstock utilization, process optimization, and sustainable energy applications

Document Type : Review Paper

Authors
1 Department of Physics, Federal University of Technology, P.M.B 1526, Owerri, Nigeria
2 Department of Biology, Federal University of Technology, P.M.B 1526, Owerri, Nigeria
Abstract
Biogas production through anaerobic digestion (AD) is an important renewable-energy pathway that supports organic-waste management, resource recovery, and decarbonization of energy systems. However, its performance varies with feedstock characteristics, process conditions, technology configuration, infrastructure, and local economic and policy conditions. This review critically synthesizes advances in biogas production technologies, emphasizing feedstock utilization, process optimization, anaerobic digestion configurations, biogas upgrading, sustainable energy applications, environmental performance, techno-economic feasibility, and emerging technological pathways. A structured literature search was conducted using Scopus, Web of Science, and Google Scholar, resulting in a final evidence base of 174 references selected through predefined eligibility and data-extraction criteria. The review shows that co-digestion, pretreatment, temperature-phased digestion, reactor optimization, and advanced process monitoring can improve methane production and operational stability, although reported performance is strongly dependent on feedstock composition and experimental conditions. The analysis further demonstrates that methane leakage, digestate management, energy requirements, and system boundaries can substantially influence the environmental benefits of AD. Economic viability is similarly context-dependent, influenced by plant scale, feedstock logistics, financing conditions, energy markets, infrastructure, and policy support. Advanced upgrading, digital monitoring, hydrogen-assisted methanation, nutrient recovery, biochar-assisted digestion, and bioelectrochemical approaches offer further opportunities, but their technological readiness and commercialization prospects differ considerably. The review identifies persistent gaps in scale-up validation, methane-loss measurement, standardized techno-economic and life-cycle assessment, feedstock variability, and deployment in developing regions. Future progress will depend on integrated systems that combine reliable methane production with methane-loss minimization, resource recovery, digital process control, economic viability, and verified life-cycle environmental performance.

Graphical Abstract

Advances in biogas production technologies: Feedstock utilization, process optimization, and sustainable energy applications
Keywords
Subjects

[1]     Sousa, M. H. d., Silva, A. S. F. d., Correia, R. C., Leite, N. P., Bueno, C. E. G., Pinheiro, R. L. d. S., … & Menezes, R. S. C. (2021). Valorizing municipal organic waste to produce biodiesel, biogas, organic fertilizer, and value-added chemicals: An integrated biorefinery approach. Biomass Conversion and Biorefinery, 12(3), 827–841.
[2]    Kapoor, R., Ghosh, P., Kumar, M., Sengupta, S., Gupta, A., Kumar, S. S., … & Pant, D. (2020). Valorization of agricultural waste for biogas based circular economy in India: A research outlook. Bioresource Technology, 304, Article 123036.
[3]    Archana, K., Visckram, A., Kumar, P. S., Manikandan, S., Saravanan, A., & Natrayan, L. (2024). A review on recent technological breakthroughs in anaerobic digestion of organic biowaste for biogas generation: Challenges towards sustainable development goals. Fuel, 358, Article 130298.
[4]    Kulichkova, G. I., Ivanova, T. S., Köttner, M., Volodko, O. I., Spivak, S. I., Tsygankov, S. P., … & Blume, Y. B. (2020). Plant feedstocks and their biogas production potentials. The Open Agriculture Journal, 14(1), 219–234.
[5]    Dioha, M. O., & Kumar, A. (2020). Exploring sustainable energy transitions in sub-Saharan Africa residential sector: The case of Nigeria. Renewable and Sustainable Energy Reviews, 117, Article 109510.
[6]   Khan, I., Chowdhury, S., & Techato, K. (2022). Waste to energy in developing countries—A rapid review: Opportunities, challenges, and policies in selected countries of Sub-Saharan Africa and South Asia towards sustainability. Sustainability, 14(7), Article 3740.
[7]    Scarlat, N., Motola, V., Dallemand, J., Monforti-Ferrario, F., & Mofor, L. (2015). Evaluation of energy potential of municipal solid waste from African urban areas. Renewable and Sustainable Energy Reviews, 50, 1269–1286.
[8]   Balasundaram, G., Banu, J. R., Varjani, S., Kazmi, A., & Tyagi, V. K. (2022). Recalcitrant compounds formation, their toxicity, and mitigation: Key issues in biomass pretreatment and anaerobic digestion. Chemosphere, 291, Article 132930.
[9]   Li, X., Wang, Z., He, Y., Wang, Y., Wang, S., Zheng, Z., … & Ying, H. (2024). A comprehensive review of the strategies to improve anaerobic digestion: Their mechanism and digestion performance. Methane, 3(2), 227–256.
[10] Dhull, P., Kumar, S., Yadav, N., & Lohchab, R. K. (2024). A comprehensive review on anaerobic digestion with focus on potential feedstocks, limitations associated and recent advances for biogas production. Environmental Science and Pollution Research, 32(32), 19129–19164.
[11]  Abonouah, K. B. S., Adjiri, A. O., & Noël, G. (2024). Biogas potential assessment of co-digestion of various wastes (cassava residues, poultry droppings and household waste) in the Gbêkê region, Bouaké, Central Ivory Coast. Biotechnology Journal International, 28(6), 165–175.
[12] Ngetuny, J., Baldauf, T., & Zörner, W. (2025). Optimizing feedstock selection for sustainable small-scale biogas systems using the analytic hierarchy process. Energies, 18(7), Article 1739.
[13] Piercy, E., Sun, X., Ellis, P. R., Taylor, M., & Guo, M. (2025). Temporal dynamics of microbial communities in anaerobic digestion: Influence of temperature and feedstock composition on reactor performance and stability. Water Research, 284, Article 123974.
[14] Wang, J. (2014). Decentralized biogas technology of anaerobic digestion and farm ecosystem: Opportunities and challenges. Frontiers in Energy Research, 2, Article 10.
[15] Bacenetti, J., Negri, M., Fiala, M., & González‐García, S. (2013). Anaerobic digestion of different feedstocks: Impact on energetic and environmental balances of biogas process. The Science of the Total Environment, 463–464, 541–551.
[16] Kemausuor, F., Adaramola, M. S., & Morken, J. (2018). A review of commercial biogas systems and lessons for Africa. Energies, 11(11), Article 2984.
[17] Tagne, R. F. T., Dong, X., Anagho, S. G., Kaiser, S., & Ulgiati, S. (2021). Technologies, challenges and perspectives of biogas production within an agricultural context. The case of China and Africa. Environment, Development and Sustainability, 23(10), 14799–14826.
[18] Kunatsa, T., & Xia, X. (2022). A review on anaerobic digestion with focus on the role of biomass co-digestion, modelling and optimisation on biogas production and enhancement. Bioresource Technology, 344, Article 126311.
[19] Kadam, R., Jo, S., Lee, J., Khanthong, K., Jang, H., & Park, J. (2024). A review on the anaerobic co-digestion of livestock manures in the context of sustainable waste management. Energies, 17(3), Article 546.
[20]           Jameel, M. K., Mustafa, M. A., Ahmed, H., Mohammed, A. R. M. I., Ghazy, H., Shakir, M., … & Kianfar, E. (2024). Biogas: Production, properties, applications, economic and challenges: A review. Results in Chemistry, 7, Article 101549.
[21] Wang, Z., Hu, Y., Wang, S., Wu, G., & Zhan, X. (2023). A critical review on dry anaerobic digestion of organic waste: Characteristics, operational conditions, and improvement strategies. Renewable and Sustainable Energy Reviews, 176, Article 113208.
[22]Sher, F., Smječanin, N., Hrnjić, H., Karadža, A., Omanović, R., Šehović, E., … & Sulejmanović, J. (2024). Emerging technologies for biogas production: A critical review on recent progress, challenges and future perspectives. Process Safety and Environmental Protection, 188, 834–859.
[23]Sangubotla, R., Gedda, G., Kim, J., & Pang, M. (2025). Emerging materials and pretreatment strategies in anaerobic digestion for biogas production: A review on recent advances, limitations, and future perspectives. Industrial Crops and Products, 236, Article 121939.
[24]Adnan, A. I., Ong, M. Y., Nomanbhay, S., Chew, K. W., & Show, P. L. (2019). Technologies for biogas upgrading to biomethane: A review. Bioengineering, 6(4), Article 92.
[25]Ardolino, F., Cardamone, G. F., Parrillo, F., & Arena, U. (2021). Biogas-to-biomethane upgrading: A comparative review and assessment in a life cycle perspective. Renewable and Sustainable Energy Reviews, 139, Article 110588.
[26]           Wang, W., Chang, J., & Lee, D. (2023). Anaerobic digestate valorization beyond agricultural application: Current status and prospects. Bioresource Technology, 373, Article 128742.
[27]Hajilary, N., Rezakazemi, M., & Shirazian, S. (2018). Biofuel types and membrane separation. Environmental Chemistry Letters, 17(1), 1–18.
[28]           Anacleto, T. M., Kozlowsky‐Suzuki, B., Björn, A., Yekta, S. S., Masuda, L. S. M., Oliveira, V. P. d., … & Enrich‐Prast, A. (2024). Methane yield response to pretreatment is dependent on substrate chemical composition: A meta-analysis on anaerobic digestion systems. Scientific Reports, 14(1).
[29]           Singh, A., Prajapati, P., Vyas, S., Gaur, V. K., Sindhu, R., Binod, P., … & Varjani, S. (2022). A comprehensive review of feedstocks as sustainable substrates for next-generation biofuels. Bioenergy Research, 16(1), 105–122.
[30]           Williams, C. L., Westover, T., Emerson, R., Tumuluru, J. S., & Li, C. (2015). Sources of biomass feedstock variability and the potential impact on biofuels production. Bioenergy Research, 9(1), 1–14.
[31] Sigurnjak, I., Poucke, R. V., Vaneeckhaute, C., Michels, E., & Meers, E. (2020). Manure as a resource for energy and nutrients. In Biorefinery of inorganics (pp. 65–82).
[32]Beggio, G., Schievano, A., Bonato, T., Hennebert, P., & Pivato, A. (2019). Statistical analysis for the quality assessment of digestates from separately collected organic fraction of municipal solid waste (OFMSW) and agro-industrial feedstock. Should input feedstock to anaerobic digestion determine the legal status of digestate? Waste Management, 87, 546–558.
[33]Alcántara, M. Á. B., Dobruchowska, J. M., Azadi, P., García, B. D., Molina-Heredia, F. P., & Reyes‐Sosa, F. M. (2016). Recalcitrant carbohydrates after enzymatic hydrolysis of pretreated lignocellulosic biomass. Biotechnology for Biofuels, 9(1).
[34]           Mukhtar, H., Ullah, N., Younas, M., Feroze, N., Ali, N., Fatehizadeh, A., & Rezakazemi, M. (2023). Torrefaction interpretation through morphological and chemical transformations of agro-waste to porous carbon-based biofuel. Ecotoxicology and Environmental Safety, 264, Article 115426.
[35]Sims, R., Hastings, A., Schlamadinger, B., Taylor, G., & Smith, P. (2006). Energy crops: Current status and future prospects. Global Change Biology, 12(11), 2054–2076.
[36]           Ferdeș, M., Paraschiv, G., Ionescu, M., Dincă, M., Moiceanu, G., & Zăbavă, B. Ș. (2023). Anaerobic co-digestion: A way to potentiate the synergistic effect of multiple substrates and microbial diversity. Energies, 16(5), Article 2116.
[37]Sheikh, Z., Karthikeyan, O. P., & Visvanathan, C. (2012). Effect of C/N ratio and ammonia-N accumulation in a pilot-scale thermophilic dry anaerobic digester. Bioresource Technology, 113, 294–302.
[38]           Sun, S., Cao, X., & Sun, R. (2016). The role of pretreatment in improving the enzymatic hydrolysis of lignocellulosic materials. Bioresource Technology, 199, 49–58.
[39]           Werkneh, A. A. (2022). Biogas impurities: Environmental and health implications, removal technologies and future perspectives. Heliyon, 8(10), Article e10929.
[40]           Jiang, Y., McAdam, E., Zhang, Y., Heaven, S., Banks, C., & Longhurst, P. (2019). Ammonia inhibition and toxicity in anaerobic digestion: A critical review. Journal of Water Process Engineering, 32, Article 100899.
[41] Ntunka, M. G., Khumalo, S. M., Makhathini, T. P., Mtsweni, S., Tshibangu, M. M., & Bwapwa, J. K. (2025). Valorization of lignocellulosic biomass to biofuel: A systematic review. ChemEngineering, 9(3), Article 58.
[42]Herrmann, A. (2012). Biogas production from maize: Current state, challenges and prospects. 2. Agronomic and environmental aspects. Bioenergy Research, 6(1), 372–387.
[43]           Brauer-Siebrecht, W., Jacobs, A., Christen, O., Götze, P., Koch, H., Rücknagel, J., … & Märländer, B. (2016). Silage maize and sugar beet for biogas production in rotations and continuous cultivation: Dry matter and estimated methane yield. Agronomy, 6(1), Article 2.
[44]           Lee, D., Bae, J., Kang, J., & Kim, K. (2016). Potential methane yield of food waste/food waste leachate from the biogasification facilities in South Korea. Journal of Material Cycles and Waste Management, 18(3), 445–454.
[45]           Calabrò, P. S., Elbeshbishy, E., Kakar, F. L., & Zema, D. A. (2025). A short bibliographic review concerning biomethane production from wastewater sludge. Waste Management & Research, 43(3), 297–305.
[46]           Cu, T. T. T., Nguyen, T. X., Triolo, J. M., Pedersen, L., Le, V. D., Le, P. D., & Sommer, S. G. (2015). Biogas production from Vietnamese animal manure, plant residues and organic waste: Influence of biomass composition on methane yield. Asian-Australasian Journal of Animal Sciences, 28(2), 280–289.
[47]Gao, R., Yuan, X., Zhu, W., Wang, X., Chen, S., Cheng, X., … & Cui, Z. (2012). Methane yield through anaerobic digestion for various maize varieties in China. Bioresource Technology, 118, 611–614.
[48]           Dai, X., Hua, Y., Dai, L., & Cai, C. (2019). Particle size reduction of rice straw enhances methane production under anaerobic digestion. Bioresource Technology, 293, Article 122043.
[49]           Møller, H. B., et al. (2020). Characterization of mechanically pretreated wheat straw for biogas production. BioEnergy Research.
[50]           Fitamo, T. M., Boldrin, A., Boe, K., Angelidaki, I., & Scheutz, C. (2016). Co-digestion of food and garden waste with mixed sludge from wastewater treatment in continuously stirred tank reactors. Bioresource Technology, 206, 245–254.
[51] Donacho, D. O., Tucho, G. T., Olani, D. D., Kabtiyimer, H. E., Hailu, A. B., & Wolde, A. D. (2023). Experimental evaluation of fresh human feces biogas and compost potential: Evidence for circular economy from waste streams in Ethiopia. Heliyon, 9(12), Article e22494.
[52]Ali, S., Hua, B., Huang, J. J., Droste, R. L., Zhou, Q., Zhao, W., … & Chen, L. (2019). Effect of different initial low pH conditions on biogas production, composition, and shift in the aceticlastic methanogenic population. Bioresource Technology, 289, Article 121579.
[53]Qiu, S., Zhang, X., Xia, W., Li, Z., Wang, L., Chen, Z., … & Ge, S. (2023). Effect of extreme pH conditions on methanogenesis: Methanogen metabolism and community structure. The Science of the Total Environment, 877, Article 162702.
[54]           Beschkov, V., & Angelov, I. (2025). Volatile fatty acid production vs. methane and hydrogen in anaerobic digestion. Fermentation, 11(4), Article 172.
[55]           Li, W., Lu, C., An, G., & Chang, S. (2017). Comparison of alkali-buffering effects and co-digestion on high-solid anaerobic digestion of horticultural waste. Energy & Fuels, 31(10), 10990–10997.
[56]           He, Q., Li, L., & Peng, X. (2017). Early warning indicators and microbial mechanisms for process failure due to organic overloading in food waste digesters. Journal of Environmental Engineering, 143(12).
[57]Boe, K. (2006). Online monitoring and control of the biogas process.
[58]           Maurus, K., Kremmeter, N., Ahmed, S., & Kazda, M. (2021). High-resolution monitoring of VFA dynamics reveals process failure and exponential decrease of biogas production. Biomass Conversion and Biorefinery, 13(12), 10653–10663.
[59]           Angelidaki, İ., Boe, K., & Ellegaard, L. (2005). Effect of operating conditions and reactor configuration on efficiency of full-scale biogas plants. Water Science & Technology, 52(1–2), 189–194.
[60]          Chow, W. L., Chong, S., Lim, J. W., Chan, Y. J., Mei, C., Tiong, T. J., … & Pan, G. (2020). Anaerobic co-digestion of wastewater sludge: A review of potential co-substrates and operating factors for improved methane yield. Processes, 8(1), Article 39. https://doi.org/10.3390/pr8010039
[61] Wei, L., Qin, K., Ding, J., Xue, M., Yang, C., Jiang, J., … & Zhao, Q. (2019). Optimization of the co-digestion of sewage sludge, maize straw and cow manure: Microbial responses and effect of fractional organic characteristics. Scientific Reports, 9(1).
[62]           Arıcı, Ș., & Koçar, G. (2014). The effect of adding maize silage as a co-substrate for anaerobic animal manure digestion. International Journal of Green Energy, 12(5), 453–460.
[63]           Paranjpe, A., Saxena, S., & Jain, P. (2023). A review on performance improvement of anaerobic digestion using co-digestion of food waste and sewage sludge. Journal of Environmental Management, 338, Article 117733.
[64]           Mu, L., Zhang, L., Zhu, K., Ma, J., Ifran, M., & Li, A. (2020). Anaerobic co-digestion of sewage sludge, food waste and yard waste: Synergistic enhancement on process stability and biogas production. The Science of the Total Environment, 704, Article 135429.
[65]           Edwiges, T., Bastos, J. A., Alino, J. H. L., D’avila, L., Frare, L. M., & Somer, J. G. (2019). Comparison of various pretreatment techniques to enhance biodegradability of lignocellulosic biomass for methane production. Journal of Environmental Chemical Engineering, 7(6), Article 103495.
[66]           Shukla, A., Kumar, D., Girdhar, M., Kumar, A., Goyal, A., Malik, T., … & Mohan, A. (2023). Strategies of pretreatment of feedstocks for optimized bioethanol production: Distinct and integrated approaches. Biotechnology for Biofuels and Bioproducts, 16(1).
[67]           Hassan, S. S., Williams, G. A., & Jaiswal, A. K. (2018). Emerging technologies for the pretreatment of lignocellulosic biomass. Bioresource Technology, 262, 310–318.
[68]           Steinbach, D., Wüst, D., Zielonka, S., Krümpel, J., Munder, S., Pagel, M., … & Kruse, A. (2019). Steam explosion conditions highly influence the biogas yield of rice straw. Molecules, 24(19), Article 3492.
[69]           Mudhoo, A., & Kumar, S. (2013). Effects of heavy metals as stress factors on anaerobic digestion processes and biogas production from biomass. International Journal of Environmental Science and Technology, 10(6), 1383–1398.
[70]           Guo, Q., Majeed, S., Xu, R., Zhang, K., Kakade, A., Khan, A., … & Li, X. (2019). Heavy metals interact with the microbial community and affect biogas production in anaerobic digestion: A review. Journal of Environmental Management, 240, 266–272.
[71] Salazar-Batres, K. J., & Moreno‐Andrade, I. (2025). Review of the effects of trace metal concentrations on the anaerobic digestion of organic solid waste. Bioenergy Research, 18(1).
[72]Yenigün, O., & Demirel, B. (2013). Ammonia inhibition in anaerobic digestion: A review. Process Biochemistry, 48(5–6), 901–911.
[73]Nakakubo, R., Møller, H. B., Nielsen, A. M., & Matsuda, J. (2008). Ammonia inhibition of methanogenesis and identification of process indicators during anaerobic digestion. Environmental Engineering Science, 25(10), 1487–1496.
[74]Chen, J. L., Ortiz, R., Steele, T. W. J., & Stuckey, D. C. (2014). Toxicants inhibiting anaerobic digestion: A review. Biotechnology Advances, 32(8), 1523–1534.
[75]Shuaib, M., Azam, N., Bahadur, S., Romman, M., Yu, Q., & Chang, X. (2021). Variation and succession of microbial communities under the conditions of persistent heavy metal and their survival mechanism. Microbial Pathogenesis, 150, Article 104713.
[76]           Bożym, M., Florczak, I., Zdanowska, P., Wojdalski, J., & Klimkiewicz, M. (2015). An analysis of metal concentrations in food wastes for biogas production. Renewable Energy, 77, 467–472.
[77]James, A., Shi, Y., Hussain, S. S., Guo, W., Liu, Q., Wang, Y., … & Pan, J. (2025). Mitigation of ammonia inhibition during anaerobic digestion: A comprehensive update. Agricultural Ecology and Environment, 1(1), 0–0.
[78]           Wang, Y., Zang, B., Gong, X., Liu, Y., & Li, G. (2017). Effects of pH buffering agents on the anaerobic hydrolysis acidification stage of kitchen waste. Waste Management, 68, 603–609.
[79]           Zhu, J., Meng, Q., Zhang, X., Zhang, X., Tang, Y., & Li, Y. (2025). Biochar enhanced anaerobic digestion of chicken manure by mitigating ammonium inhibition and improving methane production. Fermentation, 11(10), Article 549.
[80]           Dhar, H., Kumar, P., Kumar, S., Mukherjee, S., & Vaidya, A. N. (2016). Effect of organic loading rate during anaerobic digestion of municipal solid waste. Bioresource Technology, 217, 56–61.
[81] Díaz-Domínguez, E., Ibáñez-López, M. E., Pérez, M., Fernández, F., & Morales, J. L. G. (2025). Potential biomethane productivity in the temperature phased anaerobic digestion process: Impact of organic load rate and solid retention time of acidogenic phase. Chemical Engineering Journal Advances, 23, Article 100791.
[82]           Parajuli, A., Khadka, A., Sapkota, L., & Ghimire, A. (2022). Effect of hydraulic retention time and organic-loading rate on two-staged, semi-continuous mesophilic anaerobic digestion of food waste during start-up. Fermentation, 8(11), Article 620.
[83]           Olatunji, K. O., Mootswi, K. D., Olatunji, O. O., Zwane, M. I., Rensburg, N. J. v., & Madyira, D. M. (2025). Anaerobic co-digestion of food waste and groundnut shells: Synergistic impact assessment and kinetic modeling. Waste and Biomass Valorization, 16(7), 3745–3760.
[84]           Adnane, I., Taoumi, H., Elouahabi, K., Lahrech, K., & Oulmekki, A. (2024). Valorization of crop residues and animal wastes: Anaerobic co-digestion technology. Heliyon, 10(5), Article e26440.
[85]           Karthikeyan, P. K., Bandulasena, H., & Radu, T. (2024). A comparative analysis of pre-treatment technologies for enhanced biogas production from anaerobic digestion of lignocellulosic waste. Industrial Crops and Products, 215, Article 118591.
[86]           Chen, J., Ma, X., Liang, M., Guo, Z., Cai, Y., Zhu, C., … & Ying, H. (2024). Physical–chemical–biological pretreatment for biomass degradation and industrial applications: A review. Waste, 2(4), 451–473.
[87]           Nguyen, P., Tran, N. T., Nguyen, T., Dang, B., Le, M. T., Bui, X., … & Ngo, H. H. (2021). Long-term operation of the pilot scale two-stage anaerobic digestion of municipal biowaste in Ho Chi Minh City. The Science of the Total Environment, 766, Article 142562.
[88]           Kumar, A., & Samadder, S. R. (2020). Performance evaluation of anaerobic digestion technology for energy recovery from organic fraction of municipal solid waste: A review. Energy, 197, Article 117253.
[89]           Perera, H. C. S., Hosan, S., Vithanage, V., Wijesekara, D., Gunawardhana, N., Tharaka, V., … & R, K. K. (2025). Review on comparison of single stage and multistage and dry-wet anaerobic digestion for biomethane production and evaluation the waste management strategy. Radinka Journal of Science and Systematic Literature Review, 3(1), 574–589.
[90]          Maspolim, Y., Guo, C., Xiao, K., Zhou, Y., & Ng, W. J. (2016). Performance and microbial community analysis in alkaline two-stage enhanced anaerobic sludge digestion system. Biochemical Engineering Journal, 105, 296–305.
[91] Kumar, R., Neerudu, U. K., Gothalwal, R., Mohapatra, S., Deshpande, P. K., Vani, M. M., … & Merugu, R. (2021). Bioprocess parameters for thermophilic and mesophilic biogas production: Recent trends and challenges. In Clean energy production technologies (pp. 225–256).
[92]           Gebreeyessus, G. D., & Jeníček, P. (2016). Thermophilic versus mesophilic anaerobic digestion of sewage sludge: A comparative review. Bioengineering, 3(2), Article 15.
[93]           Labatut, R. A., Angenent, L. T., & Scott, N. R. (2014). Conventional mesophilic vs. thermophilic anaerobic digestion: A trade-off between performance and stability? Water Research, 53, 249–258.
[94]           Le, C., Jian, S., Bi, J., Li, Y., Chang, Z., He, J., … & Ye, X. (2016). Anaerobic digestion in mesophilic and room temperature conditions: Digestion performance and soil-borne pathogen survival. Journal of Environmental Sciences, 43, 224–233.
[95]           Zhang, X., Jiao, P., Wang, Y., Dai, Y., Zhang, M., Wu, P., … & Ma, L. (2024). Optimizing anaerobic digestion: Benefits of mild temperature transition from thermophilic to mesophilic conditions. Environmental Science and Ecotechnology, 21, Article 100440.
[96]           Nghiem, L. D., Koch, K., Bolzonella, D., & Drewes, J. E. (2017). Full scale co-digestion of wastewater sludge and food waste: Bottlenecks and possibilities. Renewable and Sustainable Energy Reviews, 72, 354–362.
[97]           Xie, S., Higgins, M. J., Bustamante, H., Galway, B., & Nghiem, L. D. (2018). Current status and perspectives on anaerobic co-digestion and associated downstream processes. Environmental Science: Water Research & Technology, 4(11), 1759–1770.
[98]           González, R., Carrillo‐Peña, D., & Gómez, X. (2022). Anaerobic co-digestion of wastes: Reviewing current status and approaches for enhancing biogas production. Applied Sciences, 12(17), Article 8884.
[99]           Nkoi, B., Lebele-Alawa, B. T., & Odobeatu, B. (2018). Design and fabrication of a modified portable biogas digester for renewable cooking-gas production. European Journal of Engineering and Technology Research, 3(3), 21–29.
[100]        Chen, Y., Hu, W., Feng, Y., & Sweeney, S. (2014). Status and prospects of rural biogas development in China. Renewable and Sustainable Energy Reviews, 39, 679–685.
[101]         Amaratunga, M. (1986). Structural behaviour and stress conditions of fixed dome type of biogas units. In Biogas technology, transfer and diffusion (pp. 295–301).
[102]        Álvarez, Y. C., Borges, R. J., Vidal, C. D. P., León, F. M. C., Buendia, J., & Nolasco, J. A. S. (2025). Design improvements and best practices in small-scale biodigesters for sustainable biogas production: A case study in the Chillon Valley, Perú. Energies, 18(2), Article 338.
[103]        Rajendran, K., Aslanzadeh, S., & Taherzadeh, M. J. (2012). Household biogas digesters—A review. Energies, 5(8), 2911–2942.
[104]        Cheng, S., Li, Z., Mang, H., Huba, E., Gao, R., & Wang, X. (2014). Development and application of prefabricated biogas digesters in developing countries. Renewable and Sustainable Energy Reviews, 34, 387–400. https://doi.org/10.1016/j.rser.2014.03.035
[105]        Kumar, A., Mandal, B., & Sharma, A. (2015). Advancement in biogas digester. In Green energy and technology (pp. 351–382). https://doi.org/10.1007/978-81-322-2337-5_14
[106]        Mapantsela, Y., Mukumba, P., Obileke, K., & Lethole, N. (2024). Portable biogas digester: A review. Gases, 4(3), 205–223.
[107]        Kulkarni, I., Zang, J. W., Leandro, W. M., Parikh, P., Adler, I., Zang, W. A. d. F., … & Campos, L. C. (2021). Closed-loop biodigesters on small-scale farms in low- and middle-income countries: A review. Water, 13(19), Article 2744.
[108]        Chowdhury, H., Chowdhury, T., Sharifi, A., Corkish, R., & Sait, S. M. (2022). Role of biogas in achieving sustainable development goals in Rohingya refugee camps in Bangladesh. Sustainability, 14(19), Article 11842.
[109]        Bond, T., & Templeton, M. R. (2011). History and future of domestic biogas plants in the developing world. Energy for Sustainable Development, 15(4), 347–354.
[110]         Ma, G., Ndegwa, P. M., Harrison, J. H., & Chen, Y. (2020). Methane yields during anaerobic co-digestion of animal manure with other feedstocks: A meta-analysis. The Science of the Total Environment, 728, Article 138224.
[111]          Weiland, P. (2009). Biogas production: Current state and perspectives. Applied Microbiology and Biotechnology, 85(4), 849–860.
[112]         Ward, A. J., Hobbs, P. J., Holliman, P. J., & Jones, D. L. (2008). Optimisation of the anaerobic digestion of agricultural resources. Bioresource Technology, 99(17), 7928–7940.
[113]         Appels, L., Baeyens, J., Degrève, J., & Dewil, R. (2008). Principles and potential of the anaerobic digestion of waste-activated sludge. Progress in Energy and Combustion Science, 34(6), 755–781.
[114]         VanderZaag, A., Baldé, H., Crolla, A., Gordon, R. J., Ngwabie, N. M., Wagner‐Riddle, C., Desjardins, R., & MacDonald, J. D. (2017). Potential methane emission reductions for two manure treatment technologies. Environmental Technology, 39(7), 851–858.
[115]         Симеонов, И., Chorukova, E., & Kabaivanova, L. (2025). Two-stage anaerobic digestion for green energy production: A review. Processes, 13(2), Article 294.
[116]         Moset, V., Poulsen, M., Wahid, R., Højberg, O., & Møller, H. B. (2015). Mesophilic versus thermophilic anaerobic digestion of cattle manure: Methane productivity and microbial ecology. Microbial Biotechnology, 8(5), 787–800.
[117]         Ahring, B. K. (2003). Perspectives for anaerobic digestion. In Advances in biochemical engineering/biotechnology (pp. 1–30).
[118]         Mata‐Álvarez, J., Dosta, J., Romero-Güiza, M., Fonoll, X., Peces, M., & Astals, S. (2014). A critical review on anaerobic co-digestion achievements between 2010 and 2013. Renewable and Sustainable Energy Reviews, 36, 412–427.
[119]         Lettinga, G., & Pol, L. H. (1991). UASB-process design for various types of wastewaters. Water Science & Technology, 24(8), 87–107.
[120]        Prussi, M., Padella, M., Conton, M., Postma, E., & Laura, L. (2019). Review of technologies for biomethane production and assessment of Eu transport share in 2030. Journal of Cleaner Production, 222, 565–572.
[121]         Tolessa, A. (2024). Current status and future prospects of small-scale household biodigesters in sub-Saharan Africa. Journal of Energy, 2024, 1–19.
[122]         Ntaganda, J., & Ahlgren, E. O. (2025). From animal waste to energy: Exploring the effects of household livelihoods on biogas technology use in Rwanda. Energy Research & Social Science, 130, Article 104443.
[123]         Kabeyi, M. J. B., & Olanrewaju, O. A. (2022). Biogas production and applications in the sustainable energy transition. Journal of Energy, 2022, 1–43.
[124]        Pizarro, C. A., Antón, A., Torrellas, M., Torres–Lozada, P., Palatsi, J., & Blasi, A. B. (2021). Environmental, social and health benefits of alternative renewable energy sources. Case study for household biogas digesters in rural areas. Journal of Cleaner Production, 297, Article 126722.
[125]        Kimutai, S. K., Kimutai, I. K., & Manirambona, E. (2024). Impact of biogas adoption on household energy use and livelihood improvement in Kenya: An overview on a roadmap toward sustainability. International Journal of Energy Sector Management, 19(3), 551–568.
[126]        Lantz, M. (2012). The economic performance of combined heat and power from biogas produced from manure in Sweden – A comparison of different CHP technologies. Applied Energy, 98, 502–511.
[127]         Su, B., Han, W., Zhang, X., Chen, Y., Wang, Z., & Jin, H. (2018). Assessment of a combined cooling, heating and power system by synthetic use of biogas and solar energy. Applied Energy, 229, 922–935.
[128]        Trommler, M., Barchmann, T., Dotzauer, M., & Cieleit, A. (2017). Can biogas plants contribute to lower the demand for power grid expansion? Chemical Engineering & Technology, 40(2), 359–366.
[129]        Pandit, S., Savla, N., Sonawane, J. M., Sani, A. M., Gupta, P. K., Mathuriya, A. S., … & Prasad, R. (2021). Agricultural waste and wastewater as feedstock for bioelectricity generation using microbial fuel cells: Recent advances. Fermentation, 7(3), Article 169.
[130]        Chin, K. F., Wan, C., Yin, L., Alaimo, C. P., Green, P. G., Young, T. M., … & Kleeman, M. J. (2020). Statistical analysis of trace contaminants measured in biogas. The Science of the Total Environment, 729, Article 138702.
[131]         Rasi, S., Läntelä, J., & Rintala, J. (2011). Trace compounds affecting biogas energy utilisation – A review. Energy Conversion and Management, 52(12), 3369–3375.
[132]         Rotunno, P., Lanzini, A., & Leone, P. (2017). Energy and economic analysis of a water scrubbing based biogas upgrading process for biomethane injection into the gas grid or use as transportation fuel. Renewable Energy, 102, 417–432.
[133]        Schmid, C. R., Horschig, T., Pfeiffer, A., Szarka, N., & Thrän, D. (2019). Biogas upgrading: A review of national biomethane strategies and support policies in selected countries. Energies, 12(19), Article 3803.
[134]        Pavičić, J., Mavar, K. N., Brkić, V., & Simon, K. (2022). Biogas and biomethane production and usage: Technology development, advantages and challenges in Europe. Energies, 15(8), Article 2940.
[135]        Dahlgren, S. (2020). Biogas-based fuels as renewable energy in the transport sector: An overview of the potential of using CBG, LBG and other vehicle fuels produced from biogas. Biofuels, 13(5), 587–599.
[136]        Arfan, M., Zhao, W., Soam, S., & Eriksson, O. (2021). Biogas as a transport fuel—A system analysis of value chain development in a Swedish context. Sustainability, 13(8), Article 4560.
[137]         Noussan, M., Laveneziana, L., Prussi, M., & Chiaramonti, D. (2025). Well-to-wheel greenhouse gas emissions comparison of electricity and biomethane urban buses. Energy Conversion and Management: X, 28, Article 101232.
[138]        Mustafi, N. N., & Ágarwal, A. K. (2019). Biogas for transport sector: Current status, barriers, and path forward for large-scale adaptation. In Energy, environment, and sustainability (pp. 229–271).
[139]        Dey, A., & Thomson, R. C. (2023). India's biomethane generation potential from wastes and the corresponding greenhouse gas emissions abatement possibilities under three end use scenarios: Electricity generation, cooking, and road transport applications. Sustainable Energy & Fuels, 7(1), 209–241.
[140]        Marconi, P., & Rosa, L. (2023). Role of biomethane to offset natural gas. Renewable and Sustainable Energy Reviews, 187, Article 113697.
[141]         Doyeni, M. O., Stulpinaitė, U., Bakšinskaitė, A., Supronienė, S., & Tilvikienė, V. (2021). The effectiveness of digestate use for fertilization in an agricultural cropping system. Plants, 10(8), Article 1734.
[142]        Saju, A., Ryan, D., Sigurnjak, I., Germaine, K. J., Dowling, D. N., & Meers, E. (2022). Digestate-derived ammonium fertilizers and their blends as substitutes to synthetic nitrogen fertilizers. Applied Sciences, 12(8), Article 3787.
[143]        Jurgutis, L., Šlepetienė, A., Šlepetys, J., & Cesevičienė, J. (2021). Towards a full circular economy in biogas plants: Sustainable management of digestate for growing biomass feedstocks and use as biofertilizer. Energies, 14(14), Article 4272.
[144]        Panuccio, M. R., Papalia, T., Attinà, E., Giuffrè, A. M., & Muscolo, A. (2018). Use of digestate as an alternative to mineral fertilizer: Effects on growth and crop quality. Archives of Agronomy and Soil Science, 65(5), 700–711.
[145]        Šlepetienė, A., Volungevičius, J., Jurgutis, L., Liaudanskienė, I., Amalevičiūtė-Volungė, K., Šlepetys, J., … & Cesevičienė, J. (2020). The potential of digestate as a biofertilizer in eroded soils of Lithuania. Waste Management, 102, 441–451.
[146]        Akbar, S., Ahmed, S., Khan, S., & Badshah, M. (2021). Anaerobic digestate: A sustainable source of bio-fertilizer. In Sustainable intensification for agroecosystem services and management (pp. 493–542).
[147]        Mukhtar, S., Yasar, A., Mahfooz, Y., Rasheed, R., Tabinda, A. B., Ashraf, M. A., … & Malik, A. (2022). Value addition and risk assessment of dairy digestate as biofertilizer on crop yield and soil fertility. Arabian Journal of Geosciences, 15(3).
[148]        Tahat, M. M., Alananbeh, K. M., Othman, Y. A., & Leskovar, D. I. (2020). Soil health and sustainable agriculture. Sustainability, 12(12), Article 4859.
[149]         Malusà, E., Pinzari, F., & Canfora, L. (2016). Efficacy of biofertilizers: Challenges to improve crop production. In Microbial inoculants in sustainable agricultural productivity (pp. 17–40).
[150]        Raha, D., Mahanta, P., & Clarke, M. L. (2014). The implementation of decentralised biogas plants in Assam, NE India: The impact and effectiveness of the National Biogas and Manure Management Programme. Energy Policy, 68, 80–91.
[151]         Kothari, R., Pandey, A., Kumar, S., Tyagi, V., & Tyagi, S. (2014). Different aspects of dry anaerobic digestion for bio-energy: An overview. Renewable and Sustainable Energy Reviews, 39, 174–195.
[152]        Chen, Y., Cheng, J. J., & Creamer, K. (2008). Inhibition of anaerobic digestion process: A review. Bioresource Technology, 99(10), 4044–4064.
[153]        Sulewski, P., Ignaciuk, W., Szymańska, M., & Wąs, A. (2023). Development of the biomethane market in Europe. Energies, 16(4), Article 2001.
[154]        Gustafsson, M., & Anderberg, S. (2022). Great expectations—Future scenarios for production and use of biogas and digestate in Sweden. Biofuels, 14(1), 93–107.
[155]        Martin, M. (2015). Potential of biogas expansion in Sweden: Identifying the gap between potential studies and producer perspectives. Biofuels, 6(5–6), 233–240.
[156]        Rajagopal, R. (2025). Enhancing low-temperature anaerobic digestion of nitrogen-rich feedstocks: Mitigating free ammonia and short-chain fatty acid inhibitions. Bioresource Technology Reports, 29, Article 102032.
[157]        Comesaña‐Gándara, B., García‐Depraect, O., Santos‐Beneit, F., Bordel, S., Lebrero, R., & Muñoz, R. (2022). Recent trends and advances in biogas upgrading and methanotrophs-based valorization. Chemical Engineering Journal Advances, 11, Article 100325.
[158]        Wechselberger, V., Reinelt, T., Yngvesson, J., Scharfy, D., Scheutz, C., Huber-Humer, M., & Hrad, M. (2023). Methane losses from different biogas plant technologies. Waste Management, 157, 110–120.
[159]        Michael Fredenslund, A., Gudmundsson, E. H., Maria Falk, J., & Scheutz, C. (2023). The Danish national effort to minimise methane emissions from biogas plants. Waste Management, 157, 321–329.
[160]        Baldé, H., Wagner‐Riddle, C., Macdonald, D. J., & VanderZaag, A. (2022). Fugitive methane emissions from two agricultural biogas plants. Waste Management, 151, 123–130.
[161]         Kvist, T., & Aryal, N. (2019). Methane loss from commercially operating biogas upgrading plants. Waste Management, 87, 295–300.
[162]        Μάνθος, Γ., Zagklis, D., Zafiri, C., & Kornaros, M. (2024). Techno-economic assessment of anaerobic digestion for olive oil industry effluents in Greece. Sustainability, 16(5), Article 1886.
[163]        Kusz, D., Kusz, B., Wicki, L., Nowakowski, T., Kata, R., Brejta, W., … & Barć, M. (2024). The economic efficiencies of investment in biogas plants—A case study of a biogas plant using waste from a dairy farm in Poland. Energies, 17(15), Article 3760.
[164]        Hazewinkel, P., Swinbourn, R., Li, C., Zhao, J., & Yang, Y. (2025). A comprehensive review of green methane production from biogas and renewable H₂ and its techno-economic assessment: An Australian perspective. Energies, 18(17), Article 4657.
[165]        Robin, T., & Ehimen, E. A. (2024). Exploring the potential role of decentralised biogas plants in meeting energy needs in sub-Saharan African countries: A techno-economic systems analysis. Sustainable Energy Research, 11(1).
[166]        Dincă, M., Ferdeș, M., Zăbavă, B., Ionescu, M., Moiceanu, G., & Paraschiv, G. (2025). Effective valorization of anaerobic digestate—A sustainable approach to circular economy. Applied Sciences, 15(16), Article 8939.
[167]        Rasimphi, T. E., Kilonzo, B., Tinarwo, D., & Nyamukondiwa, P. (2024). Challenges, opportunities, and possible interventions in the biogas sector in rural areas of Limpopo, South Africa. Energy Strategy Reviews, 56, Article 101562.
[168]        Mateescu, C., & Dima, A. (2020). Critical analysis of key barriers and challenges to the growth of the biogas sector: A case study for Romania. Biomass Conversion and Biorefinery, 12(12), 5989–6002.
[169]        Agaton, C. B., & Santos, M. J. A. (2025). Social acceptability of waste-to-energy: Research hotspots, technologies, and factors. Clean Technologies, 7(3), Article 63.
[170]        Cellini, M., Loos, S., Mirenda, C., Pisacane, L., Striebing, C., & Tagliacozzo, S. (2025). Exploring the nexus of gender and energy transitions: A systematic literature review. Energy Research & Social Science, 119, Article 103887.
[171]         Ahamed, M. I., Khan, I. M., Inamuddin, I., & Rezakazemi, M. (2024). Silver nanoparticles anchored on zinc oxide synthesized via green route as scaffold for enzymatic biofuel cell application. International Journal of Hydrogen Energy, 52, 681–693.
[172]         Marycz, M., Turowska, I., Glazik, S., & Jasiński, P. (2025). Artificial intelligence in anaerobic digestion: A review of sensors, modeling approaches, and optimization strategies. Sensors, 25(22), Article 6961.
[173]         Patrizio, P., Leduc, S., Chinese, D., Dotzauer, E., & Kraxner, F. (2015). Biomethane as transport fuel – A comparison with other biogas utilization pathways in northern Italy. Applied Energy, 157, 25–34.
[174]        Angelidaki, İ., Treu, L., Tsapekos, P., Luo, G., Campanaro, S., Wenzel, H., … & Kougias, P. (2018). Biogas upgrading and utilization: Current status and perspectives. Biotechnology Advances, 36(2), 452–466.
Volume 12, Issue 4
Issue in Progress
Autumn 2026
Pages 526-568

  • Receive Date 28 April 2026
  • Revise Date 25 August 2026
  • Accept Date 03 October 2026