Researchers of okayama university have discovered an effective mechanical compression system for drying plant biomass for energy generation without the need for thermal drying. This is important because plant biomass contains more than 50% moisture, requiring mechanical methods (or heating and natural seasoning) to reduce this to around 35% – to increase energy generation efficiency when the biomass is used as fuel .
This new method can be applied to both woody and herbaceous plants and generates a compression fluid containing water-soluble lignin that has fundamental antiviral properties against influenza and swine epidemic diarrhea viruses.
According to the university, the current system of mechanical compression is inefficient because the required thermal drying process requires a lot of energy and time and often involves expensive, cumbersome equipment. Not only that, but the compressed liquid produced as a byproduct in most of these methods does not contain water-soluble lignin – an important structural polymer in plant cells with numerous applications.
The researchers were led by Dr. Toshiaki Ohara, an assistant professor in the Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences at Okayama University. The study describes the researchers' use of cedar planks and chips as woody biomass and the ginger spice species Alpinia zerumbet as herbaceous biomass to test the new mechanical rolling compression method. They found that cedar board and Alpinia zerumbet were compressed more effectively than cedar chips.
“With our technique, all plants could be compressed; however, cedar and Alpinia zerumbet were compressed more effectively than cedar chips, which were compressed randomly. This suggests that compression along plant vessels, such as straw, is essential for effectiveness,” said Dr. Ohara. Plant vessels are tissues in vascular plants associated with the transport of nutrients and water.
After compression, the researchers crushed and pelletized the residues to determine their combustion performance, an indicator of their potential as biomass for energy generation. The liquid obtained as a byproduct of the compression was filtered, its lignin content and structure were determined, and its antiviral properties were evaluated using cell viability assays.
The cedar wood pellets showed a higher heat value when burned, which was in line with ISO standards, testifying to their higher energy performance. The ginger spice variety produced more water-soluble lignin, but the heat value upon combustion was slightly lower, at 95% of ISO standards. However, both cedarwood and Alpinia zerumbet compression fluids significantly inhibited influenza and swine epidemic diarrhea virus infection.
Dr. Yuta Nishina of the Research Core for Interdisciplinary Sciences, Okayama University, a co-author of the study, noted: “The non-chemically extracted, water-soluble lignin obtained by this method may find applications in the field of medicine , cosmetics and livestock farming. Cattle breeding."
Moreover, the water-soluble lignin with high carbon content can be used in the production of carbon nanomaterials and contribute to reducing carbon-induced pollution.
Dr. Summarizing the benefits of their technique, Ohara stated: “Our method does not require time, a warehouse or additional thermal drying, allowing it to be performed on site. This compressor can press both wood and herbs, allowing us to stimulate the generation of electricity from biomass using locally grown plants. These characteristics are beneficial for promoting local sustainability.”
Source: bioenergy-news
