Effects of Ultrasonic and Microwave Pretreatment on Lipid Extraction of Microalgae and Methane Production from the Resid
- PDF / 1,121,198 Bytes
- 9 Pages / 595.276 x 790.866 pts Page_size
- 20 Downloads / 169 Views
Effects of Ultrasonic and Microwave Pretreatment on Lipid Extraction of Microalgae and Methane Production from the Residual Extracted Biomass Magdalena Rokicka 1 & Marcin Zieliński 1
&
Magda Dudek 1 & Marcin Dębowski 1
Received: 1 July 2020 / Accepted: 5 October 2020 # The Author(s) 2020
Abstract The extraction of lipids from microalgae cells of Botryococcus braunii and Chlorella vulgaris after ultrasonic and microwave pretreatment was evaluated. Cell disruption increased the lipid extraction efficiency, and microwave pretreatment was more effective compared with ultrasonic pretreatment. The maximum lipid yield from B. braunii was 56.42% using microwave radiation and 39.61% for ultrasonication, while from C. vulgaris, it was respectively 41.31% and 35.28%. The fatty acid composition in the lipid extracts was also analyzed. The methane yield from the residual extracted biomass pretreated by microwaves ranged from 148 to 185 NmL CH4/g VS for C. vulgaris and from 128 to 142 NmL CH4/g VS for B. braunii. In the case of ultrasonic pretreatment, the methane production was between 168 and 208 NmL CH4/g VS for C. vulgaris, while for B. braunii ranging from 150 to 174 NmL CH4/g VS. Anaerobic digestion showed that lipid-extracted biomass presented lower methane yield than non-lipid-extracted feedstock, and higher amount of lipid obtained in the extraction contributed less methane production. Anyway, anaerobic digestion of the residual extracted biomass can be a suitable method to increase economic viability of energy recovery from microalgae. Keywords Cell disruption . Lipid recovery . Fatty acid methyl esters . Anaerobic digestion . Microalgae
Introduction Nowadays, there is an increasing demand for energy carriers obtained from renewable sources arising in harmony and respect for the natural environment. Moreover, an important issue is searching for the non-food bioenergy feedstocks to reduce the consumption of the food and feed sources [1]. Due to the rapid growth rate of the microalgae and their easy adaptation to environmental conditions, this biomass is currently considered an alternative feedstock for the production of biofuels replacing the fossil fuels [2, 3]. Microalgae have many intracellular substances that can be widely used in the food and cosmetics industries. They can be also used in the production of the liquid and gaseous biofuels such as biodiesel, bioethanol, biohydrogen, and biogas [4–6]. More
* Marcin Zieliński [email protected] 1
Department of Environmental Engineering, University of Warmia and Mazury in Olsztyn, Warszawska Str. 117A, 10-720 Olsztyn, Poland
attention has been recently paid to research on lipid extraction from microalgae. According to the literature, microalgae appear to be a promising source for biodiesel production to meet the global demand for transport fuels [7, 8]. Microalgae cells are protected by the complex cell walls which consist of lipid, cellulose, protein, glycoprotein, and polysaccharide. The fundamental cell wall components include a microfibrillar networ
Data Loading...
