Comparative scoping study report for the extraction of microalgae oils from two subspecies of Chlorella vulgaris

The production of microalgae as a fatty acid oil resource for use in biofuels production is a widespread research topic at the lab scale. Microalgae contain a higher lipid content on a dry-weight basis compared to oilseeds such as soybeans. Additionally, the growth and cultivation cycle of microalgae is 15 days, in comparison to soybeans, for which the cycle occurs once or twice annually. However, to date, it has been uneconomical to produce microalgae oils in a world-scale facility due to limitations in cultivating microalgae at commercial scales. Recent developments suggest that the use of heterotrophic microalgae may be economically feasible for large-scale oil production. To assess this feasibility, a comparative scoping study was performed analysing the feasibility of an industrial-scale process plant for the growth and extraction of oil from microalgae. Processes were developed at the preliminary design level using heterotrophic subspecies and autotrophic subspecies of Chlorella vulgaris. AACE Class 4 cost estimates and economic analyses were performed. This study concludes that processes based on heterotrophic microalgae are more likely to reach economic feasibility than processes using autotrophic microalgae. However, a few barriers still remain to achieving free-market economic viability

The Impact of Investment Arbitration on Investment Treaty Design: Myth Versus Reality

Investor-state arbitration (ISA) has shaped the practice, scholarship and teaching of international investment law, but to what extent has it shaped its substance? According to anecdotal evidence, states change their investment treaties in response to developments in investment arbitration. To separate myth from reality this article empirically investigates the effect of investment arbitration on treaty making through three impact channels: (1) investment clauses, (2) investment claims and (3) investment case law coding close to 1700 international investment agreements (IIA) across 55 clauses. Our analysis sheds new light on several normative debates within the field. First, we find that the omission or inclusion of investment clauses has no material effect on other treaty design elements. This suggests that ISA clauses are procedural add-ons, which bestow investors with enforcement rights, but do not alter the inter-state nature of the treaties’ substantive obligations. Second, contrary to prior anecdotal and empirical evidence, investment claims do not lead to systematic treaty design changes. Most innovation attributed to investment claims actually pre-dates them. Moreover, only in few countries did investment claims trigger treaty design changes. Hence, rather than worrying about overzealous responses by states to “rebalance” IIAs in the face of investment claims, we should be concerned about the field’s path-dependency and its entrenchment in a pre-arbitration architecture. Third, investment case law exerts the strongest impact on treaty making as controversial interpretive outcomes in investment arbitration trigger traceable changes in treaty design. Hence, states are more active in fine-tuning existing commitments than in designing new ones further entrenching IIAs’ path dependency and lack of innovation

Production of 1,3-butadiene and ε-caprolactam from C6 sugars: Techno-economic analysis

This study assesses the techno-economic performance of production lines for obtaining 1,3-butadiene and ε-caprolactam from C6 sugars. Process models were developed to assess their technical performance and to derive inputs for economic analysis. The economic assessment was carried out using net present value (NPV) and production costs as indicators. Sensitivity analyses were carried out to account for the effects of variations in inputs, such as processing capacity, valorization of humins, and prices, on the economic outputs. Results indicate that both production lines perform similarly from an energy intensity point of view (34-50 MJ/kg of main product). However, in terms of yield (kg of product per kg C6 sugar), caprolactam shows higher values by a factor of 1.6-3.6 in comparison to that of butadiene. The butadiene production line is not economically attractive, showing a negative NPV (-647 to -642 M€) and production costs 3-5 times higher than the reference market price (Case I 4369 €/tonne, Case II 3406 €/tonne). The caprolactam production line seems to be unfeasible with negative NPV (-229 M€) and production costs 30% higher than the reference price (Case III 2595 €/tonne, Case IV 1875 €/tonne). However, if the production yield is increased, the caprolactam production line becomes economically attractive with production costs 6% lower than its reference market price. The production costs of caprolactam can be further decreased if the process capacity is increased, reflecting the benefits of the economies of scale, as well as including heat and power produced from humins. Overall, the caprolactam production line shows higher economic potential