Research progress, trends, and updates on anaerobic digestion technology: A bibliometric analysis

Anaerobic digestion (AD) is a consolidated waste management technology with numerous publications on this topic. Consequently, using Scientometric tools can be insightful to depict and analyze research gaps and trends towards updating scientific datasets and upgrading knowledge in this research area. Therefore, this bibliometric review examined the research progress, trends, and updates on AD technology. The Web of Science© database was used to select the documents, and the softwares VOSviewer© and Bibliometrix were used to carry out the bibliometric investigation. The results obtained in this bibliometric study highlight that the hot topics in the field over the last five years of publications are associated with environmental studies for biogas production to avoid greenhouse gas emissions, focusing on the microbiological and engineering parameters involved. There is a lack of information regarding the recovery of bioenergy from organic waste. The main opportunities and trends can be associated with the integration of feedstock pretreatment prior to the core processing of substrates by AD with a view to improve biogas production and quality. The production of bioenergy and biofuels from AD processes can be an alternative to meet the relevant Sustainable Development Goals. Finally, the knowledge on feedstock pre-treatment with process modeling, optimization, and operation, is crucial to establish AD as a profitable management system reaping alongside significant economic and environmental benefits.