Engineering Management of Gas Turbine Power Plant Co 2 for Microalgae Biofuel Production (original) (raw)
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In the new frontier of energy, biofuels will play an important role in overcoming our dependence on fossil fuels and its associated environmental impacts. In the biofuels sector, the exploitation of microalgal biomass has the potential to be beneficial, as they do not compete on land use with food crops and their cultivation systems can be designed to have a lower water footprint. Even though a number of LCAs (Life Cycle Assessment) involving biofuel production from microalgae have been reported, few of them have focused on the use of by-product streams in algal biomass production, such as wastewater or waste CO 2 recovered from flue gas, which could further reduce the environmental impact of the recovered biofuels, and none have considered a combination of different by-product streams. In this paper, an LCA is applied to compare 6 alternative scenarios, where the potential environmental benefits achievable using CO 2 from different sources (commercial liquid CO 2 , CO 2 recovered from flue gas and flue gas as is) and wastewater in the cultivation of microalgae for the production of biofuels are investigated. The analysis is based on a virtual, but realistic case, using an open microalgal cultivation pond facility located in Kingston (Canada). The results indicate that the source of CO 2 is the most relevant factor affecting environmental impacts, and that the direct injection of flue gas into the algal pond and the use of wastewater represent the most environmentally friendly alternative.
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Carbon dioxide biofixation and biomass production from flue gas of power plant using microalgae
2012 Second Iranian Conference on Renewable Energy and Distributed Generation, 2012
Nowadays greenhouse gas emission induces environmental problems such as climate change worldwide. According to statistics, atmospheric CO 2 concentration increased from 280 ppm in 1800 to 380 ppm in 2004 and power plants account for 22% of global CO 2 emission. Microalgae have potential for up taking inorganic carbon during photosynthesis. They have advantage in containing high oil content which can be used for biofuel production. The effect of other pollutants such as NOx and SOx gases on these microorganisms growth should be evaluated if power plant effluent gas is sought to be injected into a photobioreactor. Among three evaluated microalgae, Chlorella vulgaris, Dunaliella tertiolecta and Scenedesmus obliqus, higher biomass productivity obtained from C. vulgaris.
Energies, 2019
Exhaust gases from thermal power plants have the highest amount of carbon dioxide (CO2), presenting an environmental problem related to a severe impact on ecosystems. Extensively, the reduction of CO2 from thermal power plants has been considered with the aid of microalgae as a cost-effective, sustainable solution, and efficient biological means for recycling of CO2. Microalgae can efficiently uptake CO2 and nutrients resulting in high generation of biomass and which can be processed into different valuable products. In this study, we have taken Nephroselmis sp. KGE8, Acutodesmus obliquus KGE 17 and Acutodesmus obliquus KGE32 microalgae, which are isolated from acid mine drainage and cultivated in a photobiological incubator on a batch scale, and also confirmed that continuous culture was possible on pilot scale for biofuel production. We also evaluated the continuous culture productivity of each cultivate-harvest cycle in the pilot scale. The biomass of the cultivated microalgae wa...
CO2 recycling using microalgae for the production of fuels
Applied Petrochemical Research, 2014
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Microalgae mass cultures can use solar energy for the biofixation of power plant flue gas and other concentrated CO 2 sources into biomass that can be used to produce renewable fuels such as methane, ethanol, biodiesel, oils and hydrogen and for other fossil-fuel sparing products and processes. They thus can mitigate emissions of fossil CO 2 and other greenhouse gases. Microalgae are currently used commercially in the production of high-value nutritional products, in wastewater treatment and in aquaculture. One commercial microalgae production plant, in Hawaii, is already using flue gas from a small power plant as an exogenous source of the CO 2 required to grow algal biomass. Although still a relatively small industry (total production is only a few thousand tons of algal biomass per year world-wide), microalgae technologies have been extensively studied over the past decade in the context of greenhouse gas mitigation, specifically in Japan and the U.S.
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ENERGY CONVERSION FROM MICROALGAE TO BIOFUELS: A REVIEW
LAP LAMBERT ACADEMIC PUBLISHING , 2022
Continued overconsumption of fossil energy and carbon pollution problems urged steadily increasing research efforts on the utilization of renewable energy sources as an alternative fuel to fossil fuels. Biofuels are substances derived from or residues of biomass, including biogas, biodiesel, bioethanol, biomethanol, synthetic biofuels, biohydrogen, and bio-oil. Because of their properties, all of these biofuels can be used in traditional engines directly or mixed with fossil fuels. First and second generation biofuels can be produced from a wide range of feedstocks (including food crops such as sunflower, sugar cane, peanut, soybean, cotton, palm, and so on) as well as energy crops such as lignocellulosic masses and waste (i.e., municipal solid waste organic fraction or landfill leachate). The third generation of biofuels derived from microalgae which has been attracted increasing attention in recent years. While their yield is higher and their greenhouse gas impact is lower than the first two generations. They still require new technologies to produce biofuels and other value�added products in order to reduce biofuel costs. Fourth-generation biofuels (solar fuels) are also introduced because they are inexpensive and have a readily available feedstock to meet the world's energy needs. The most common biofuels (biogas, syngas, biodiesel, bioethanol, and biobutanol) produced from microalgae, as well as various applications of microalgae, are discussed in this article, as the current trends and the future of the bioenergy sector centred on algae.
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