Global Metabolome Analysis of Dunaliella tertiolecta, Phaeobacter italicus R11 Co-cultures using Thermal Desoprtion - Comprehensive Two-dimensional Gas Chromatography - Time-of-Flight Mass Spectrometry

Dunaliella tertiolecta is a marine microalgae that has been studied extensively as a potential carbon-neutral biofuel source. Microalgae oil contains high quantities of energy-rich fatty acids and lipids, but is not yet commercially viable as an alternative fuel. Carefully optimised growth conditions, and more recently, algal-bacterial co-cultures have been explored as a way of improving the yield of Dunaliella tertiolecta microalgae oils. The relationship between the host microalgae and bacterial co-cultures is currently poorly understood. Here, a complete workflow is proposed to analyse the global metabolomic profile of co-cultured Dunaliella tertiolectra and Phaeobacter italicus R11, which will enable researchers to explore the chemical nature of this relationship in more detail.

Assessment of Microalgae Oil as a Carbon-Neutral Transport Fuel: Engine Performance, Energy Balance Changes, and Exhaust Gas Emissions

Notwithstanding the substantial progress acheved since 2010 in the attempts to realize the potential of microalgae biofuels in the transportation sector, the prospects for commercial production of CO2-neutral biofuels are more challenging today than they were in 2010. Pure P. moriformis microalgae oil was subjected to unmodified engine performance testing as a less investigated type of fuel. Conventional diesel was used as a reference fuel to compare and to contrast the energy balances of an engine as well as to juxtapose performance and emission indicators for both unary fuels. According to the methodology applied, the variation of BSFC rates, BTE, smoke opacity, NOx, HC, CO2, O2, and exhaust gas temperature on three different loads were established during compression ignition (CI) engine operation at EGR Off, 25% EGR, 18% EGR and 9% EGR modes, respectively. Simulation model (AVL Boost/BURN) was employed to assess the in-cylinder process parameters (pressure, pressure rise, temperature, temperature rise, ROHR, and MFB). Furthermore, the first law energy balances for an engine running on each of the test fuels were built up to provide useful insights about the peculiarities of energy conversion. Not depending on EGR mode applied, the CI engine running on microalgae oil was responsible for slightly higher BTE values, drastically reduced smoke opacity, higher CO2 values, and smaller O2 concentration, marginally increased NOx levels and lower total energy losses (in %) if compared to the performance with diesel fuel.

Prognostic Assessment of the Performance Parameters for the Industrial Diesel Engines Operated with Microalgae Oil

A study conducted on the high-speed diesel engine (bore/stroke: 79.5/95.5 mm; 66 kW) running with microalgae oil (MAO100) and diesel fuel (D100) showed that, based on Wibe parameters (m and φz), the difference in numerical values of combustion characteristics was ~10% and, in turn, resulted in close energy efficiency indicators (ηi) for both fuels and the possibility to enhance the NOx-smoke opacity trade-off. A comparative analysis by mathematical modeling of energy and traction characteristics for the universal multi-purpose diesel engine CAT 3512B HB-SC (1200 kW, 1800 min−1) confirmed the earlier assumption: at the regimes of external speed characteristics, the difference in Pme and ηi for MAO100 and D100 did not exceeded 0.7–2.0% and 2–4%, respectively. With the refinement and development of the interim concept, the model led to the prognostic evaluation of the suitability of MAO100 as fuel for the FPT Industrial Cursor 13 engine (353 kW, 6-cylinders, common-rail) family. For the selected value of the indicated efficiency ηi = 0.48–0.49, two different combinations of φz and m parameters (φz = 60–70 degCA, m = 0.5 and φz = 60 degCA, m = 1) may be practically realized to achieve the desirable level of maximum combustion pressure Pmax = 130–150 bar (at α~2.0). When switching from diesel to MAO100, it is expected that the ηi will drop by 2–3%, however, an existing reserve in Pmax that comprises 5–7% will open up room for further optimization of energy efficiency and emission indicators.

Role of Microalgae as a Source for Biofuel Production in the Future: A Short Review

The continued burning of fossil fuels since the beginning of the last century led to higher emissions of greenhouse gases and thus leads to global warming. Microalgae are one of the most important sources of green hydrocarbons because this type of algae has a high percentage of lipids and has rapid growth, consumes the carbon dioxide in large quantities. Besides, the cultivation of these types of algae does not require arable land. This review aims to explain the suitability of microalgae as a biofuel source depending on the fat content, morphology, and other parameters and their effect on the conversion processes of microalgae oil into biofuels by different zeolite catalytic reactions. It also discusses in detail the major chemical processes that convert microalgae oil to chemical products. This review sheds light on one of the most important groups of microalgae (Chlorella vulgaris microalgae). This review includes a historical overview and a comprehensive description of the structure needed to develop this type of algae. The most important methods of production, their advantages and disadvantages are also deliberated in this work. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).