Techno-economic Analysis of Microalgae-Based Lipid Production: Considering Influences of Microalgal Species

Abstract

In this study, a techno-economic analysis is performed to analyze the effect of the choice of microalgal species on the economics of microalgae-based lipid production. Three microalgal species (Chlorella vulgaris, Tetraselmis suecica, and Nannochloropsis sp.) are selected given their disparate cell characteristics and high promise as feedstocks for commercial-scale microalgae-based lipid production. In the economic analysis, significantly different total production costs are obtained for the three species ($6.5/kglipid, $7.0/kglipid, and $8.3/kglipid for Chlorella vulgaris, Tetraselmis suecica, and Nannochloropsis sp., respectively), and the percentage of each processing stage contributing to the total cost also turned out to be quite different depending on the species. On the basis of the economic analysis, a sensitivity analysis is performed to analyze the effect of different cell characteristics on the overall economics, and to identify the most influential characteristic. The further scenario-based analysis shows that the economic results, as well as the relative standings of the species, change significantly when processing technologies are changed, pointing to the need to optimize the processing pathway individually for each species for a fair evaluation.

Technoeconomic Evaluation of Microalgae Oil Production: Effect of Cell Disruption Method

“…Seongwhan et al [47] report a production cost of USD 6.5/kg of lipids obtained from the microalgae Chlorella vulgaris, much lower than in this study. It is also mentioned that the scenario analysis shows that economic results change significantly when processing technologies are changed.…”

Strategies to Produce Cost-Effective Third-Generation Biofuel From Microalgae

“…Despite this, several strategies have been developed to lower the cost of microalgal biodiesel production, discussions of which have been largely excluded from the recent literature that primarily focuses on the benefits and composition of microalgal biodiesel, insights into the processes and process factors that affect yield, and efficient harvesting and extraction methods (Satpati and Pal, 2018;Shin et al, 2018;Tan et al, 2018;Deshmukh et al, 2019;Goh et al, 2019;Peng et al, 2020;Ananthi et al, 2021). Moreover, cost minimization strategies have been applied primarily to dewatering, harvesting, and pretreatment mechanisms to minimize the total production cost (Kang et al, 2018), rather than cultivation which can also make up a significant proportion of the cost. In addressing these knowledge gaps, this review paper briefly provides some essential insights into the technologies and economics of techniques used to reduce costs for microalgae-based biodiesel production to guide future research into large-scale applications.…”

Experimental and Techno-Economic Study on the Use of Microalgae for Paper Industry Effluents Remediation

“…Regarding suspended cultivation systems, they can be open or closed reactors. Despite all the drawbacks of growing microalgae in open reactors, these systems are less expensive than closed ones, are more suitable for large-scale production of microalgal biomass, and can achieve promising biomass productivities, when the selected strain is robust, and the environmental conditions are adequate for their growth [27,28]. Considering these advantages, open systems were proposed in this project.…”

“…Carbon is supplied to the culture through the injection of flue gases resulting from: (i) the biomass plant of the paper company; and (ii) the combined heat and power (CHP) units from the proposed biorefinery and the paper company, where generators burn biogas to produce, simultaneously, electricity and heat. The carbon is assumed to be supplied as 100% CO 2 and to be free from any impurity that might negatively impact microalgal growth (e.g., sulfur or nitrogen oxides) [28]. Biomass harvesting is done following a two-stage approach [29,30]: (i) first, a thickening step, flocculation, is applied to make biomass settle faster in the clarifier and to separate it from the culture medium (S 03 ) more easily; and (ii) a dewatering step will be promoted, where biomass is centrifuged to end up with a concentration of approximately 20% (w/w) (S 04 ).…”

“…Regarding biomass harvesting, thickening and dewatering steps were considered. The thickening step consisted of adding sodium hydroxide (NaOH) to increase the pH and induce autoflocculation, which leads to the formation of large flocs that can be easily separated from the medium by gravity sedimentation [28]. To induce the flocculation of 1 g of microalgal biomass at a pH of 10.8, it was assumed that 9 mg of NaOH were required, which accounts for a concentration factor of 4 [48].…”