Produção de hidrogênio como fonte de energia e estratégia de gestão de resíduos e mudanças climáticas

Abstract

With the increasing population growth and industrial development, the level of waste generated by human beings and industries has reached an alarming point. Allied to this fact, the air pollution brings to light the need to develop sustainable techniques and cleaner energy production which could give added value to these wastes. Hydrogen gas can be a clean energy source, having the highest heat content per unit of mass among all the fuels we use, and having a very high potential as an energy carrier. The biological hydrogen production involves using microorganisms which degrade the organic matter present in organic waste in an anaerobic way, in order to provide hydrogen at the end of the process. In this context, the present study aims to carry out an analysis of scientific publications on the subject, presenting the most relevant works, detailing the most important parameters for the hydrogen production from organic waste, and comprising global references on the matter. For this, a detailed analysis of scientific data was performed using the database on the Web of Science. China is the country with the largest number of publications on this topic, and the year 2020 stood out as the most prolific in terms of number of studies. The articles constitute 83.72% of the studies found in the research, and the two scientific journals that published the most were Bioresource Technology and the International Journal of Hydrogen Energy. The results found in the Web of Science were refined based on the relevance given by the platform, selecting 42 articles for analysis. Among them, 45.23% had the objective of optimizing the hydrogen production, and the two most varied parameters to verify the influence on the H2 production were the organic loading rate and the hydraulic retention time, in 21.42% of the studies. The batch reactor was the most used, in 35.71 of the studies. In 72% of the studies, the temperature was used in the mesophilic range, between 35 and 38 oC. The most used pH was in the range between 5 and 6, and in relation to the organic loading rate (OLR) the vast majority used 4 to 100 g COD / L.day. The hydraulic retention times used were in the range between 6 h and 36 h.