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Algae biofuels have been studied numerous times including the Aquatic Species program in 1978 in the U.S., smaller laboratory research projects and private programs.
Using Molina Grima 2003 and Department of Energy figures, captial costs and operating costs of the closed systems and open systems were estimated. Cost per gallon of conservative estim...
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... fuel will self-ignite when pressurized in the cylinder, whereas gasoline needs a spark from a spark plug to combust. Diesel fuel also has more carbon atoms per molecule than gasoline, thus the energy density of diesel is greater than that of gaso- line (Table 1). Diesel engines are relatively more efficient than gasoline engines as well, though they are required to work at higher temperatures, so some energy is lost to heat. ...
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... hexane is used as a solvent in the transesterification reaction, and thus can be recycled for reuse. Sensitivity analysis for the closed systems is presented in Table 10. Given that the major cost of bio- diesel is the cost of algae, and thus the capital cost of constructing photo bioreactor systems, it is difficult to imagine closed system sourced biodiesel being viable. ...
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... as before, hexane recov- ery could also reduce costs. Scenarios are presented in Table 11. Improved yields greatly help algae biofuels to nearly achieve the cusp of economic feasibility. ...
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... model clearly shows that closed system method of production of algae biodiesel, despite its immunity to contamination, is prohibitively expensive. The policies for incentivizing biofuel production that are currently in place, most notably the monetary assistance of the Bio- diesel Tax Credit, could potentially allow algae biodiesel to be produced profitably using an open pond system given certain assumptions about the costs of algae bio- diesel production (Table 12). In addition, the market created by the Renewable Fuel Standard offers profit- ability even if algae biodiesel does not meet these conditions. ...
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... algae biodiesel is carbon neutral overall and con- sumes CO 2 in the production process, it is in the prime position of being able to sell emissions credit. However, given current futures prices from the European Climate Exchange (Table 13), this method of offsetting CO 2 costs is currently not feasible. Carbon trading schemes must become more robust, i.e. expensive, to allow an algae biodiesel producer to sell carbon offsets. ...
Citations
... Chlorella'nın yüksek lipid üretkenliğine sahip olması, onu biyodizel üretimi için ideal bir seçim hâline getirmektedir (Al-lwayzy et al., 2014;Al-lwayzy & Yusaf, 2013). Diğer yandan, biyoyakıt üretimi için biyokütle oluşturmak üzere atık su üzerinde alg yetiştirilmesi sırasında alglerin suda bulunan organik kirleticileri işleyerek çevreyi temizlediği de görülmektedir (Gao et al., 2012). ...
... The availability of light, together with nitrogen, phosphorus, carbon dioxide, or any other source of carbon, is essential for the efficient synthesis of algal biomass. Using enclosed PBRs or large open ponds (open raceways, ORWs) for commercial microalgal production, the key to success is selecting the microalgal species that thrive in that environment [110,111]. ORWs are lagoons or shallow ponds that range in depth from 10 to 50 cm, are constructed of concrete, or are simply ponds dug out of the ground, and are lined with a plastic material such as high-density polyethylene or polyvinyl chloride (PVC). PBRs are closed systems that can be made of polyethylene bags bathed in a thermostatic water bath, tubular photobioreactors (TPBRs), flat panel photobioreactors (FPBRs) designs, or both [112]. ...
Microalgae have shown their extravagant potency as a prominent source for the production of biomass, which has opened the gates for biofuel, bioenergy generation, and down-streaming in today’s third-world developing countries. They are competent in producing smaller land footprints while engendering high yields of biomass and fuel overall. By their nature, they have the potential to avail the land that is incapacitated for food production and flourishes there without bringing forth disruption to the economy in any form. Since microalgae are perennial along with excellent tolerance towards pH changes, their current demand is skyrocketing. The review paper, sails on the generation of biohydrogen, biomethane, and bioelectricity using microalgae as the primordial constituents, with the mechanisms and pitfalls confronted throughout the process. Alongside, this paper also covers the involvement of microalgae in the treatment of wastewater and biohydrogen production using dark fermentation. Biomethane is one of the prime biogas generated upon methanogenesis and fermentation when carried out employing microalgae. The paper’s greater aims are also to highlight the production of bioelectricity using microbial electrochemical cells and microbial fuel cells. The outcome of this review can provide a research update on the efficiency of algal biomass as a promising raw material for various biofuels paving a way for finding research gaps towards future exploration.
... [1] states that the need for this energy is mostly obtained from fossil-based mining whose existence is decreasing from year to year and requires large capital to obtain it. In addition, according to [2] and [3] the issue of global climate change is an important background for finding alternative materials as renewable energy sources such as geothermal, wind, solar power, waves, and of course, microalgae which are more environmentally friendly. [4] stated that the selection of microalgae as a raw material for alternative energy is environmentally friendly because it has high growth, does not compete as a food product, does not require a large area, and is easy for mass culture. ...
... As a source of environmentally friendly alternative energy raw materials [7], microalgae have several advantages such as high productivity in a short time [8], [9], and [10], efficient conversion of sunlight into energy, high ability to synthesize fat [11], and [9], able to grow in extreme conditions, does not require a lot of nutrients [12] and does not compete with food products [13], and [14]. Another advantage according to [3], and [15] states that biodiesel fuel can lubricate the engine well compared to fossil fuels which require additional sulfur to lubricate the engine as well as bioethanol. A pure culture system for providing raw material for biofuel from microalgae is an effective way to obtain the type of microalgae with the desired content. ...
Microalgae are organisms that have many variations of species that are very suitable to be developed in all Indonesian waters for use as food, medicine, and biofuels. The method used in this research is a survey method, which is a descriptive study to describe/describe the nature of a phenomenon/condition that existed at the actual time and examine the causes of certain symptoms. The stages of this research include determining the location of the research, data collection techniques, and data analysis of the results of the studies that have been carried out. The data analysis in question was in the form of statistical analysis to compare the proximate content in the form of lipids, starch, and sucrose from microalgae from each sampling location. Correlation tests were also carried out between water nutrient variables, the dominance of microalgae species, and the proximate content of microalgae when sampling was carried out. The results showed that the microalgae species that grew and dominated the media included Skeletonema, Chaetoceros, Diatomae, and Chlorella.
... Algae can produce 3,800-50,800 liters/ha per year. However, there are some disadvantages, such as the prohibitively high cost of the technology required to create it [157,158]. ...
Due to an increase in fuel demand and efforts to lessen greenhouse gas (GHG) emissions, countries around the globe are searching for different clean energy sources such as biodiesel. Biodiesel is a renewable energy source that appears to be an ideal solution to meet global energy needs, including in Ethiopia. Ethiopia imports much fossil fuel each year and there is an effort to supplement the 2 energy requirement of the country through biofuel development. However, comprehensive assessments of biodiesel's potential, challenges, and production technologies are lacking. This review aimed to explore the technological advancement, opportunities, challenges, and prospects of using biodiesel in Ethiopia. The latest data from governmental reports and several articles published in reputable journals were used as sources. Transesterification with methanol and catalysts is the general method used to produce biodiesel. The high biodegradability, minimal toxicity, and almost zero emissions are unique characteristics of biodiesel. Therefore, biodiesel can substitute fossil fuels in numerous applications, including transportation and internal combustion engines, without requiring major retrofits, and appears to improve the rural economic potential and environmental protection. The results of many studies have shown that the combustion features and the engine power output of biodiesel were comparable to that of fossil fuel diesel. The production of biodiesel has several environmental and socioeconomic advantages. Using biodiesel in diesel engines for daily operations is advantageous due to its environmental friendliness such as less CO2 emissions and staying a long time without denaturing the chemical properties. Due to the rapid growth in car ownership in recent years, the demand for fossil fuels needs to substitute with alternative energy sources like biodiesel. Moreover, transportation has become an integral component of the life of the people but the dependency of energy on fossil fuels needs to be replaced by biofuel like biodiesel. Ethiopia has a huge biodiesel potential due to the existence of many biofuel crops. Imports of petroleum-based fuel will be reduced if all players in the energy sector collaborate to promote the production of biodiesel from a variety of sustainable feedstocks. This can be accomplished by adopting existing biodiesel technologies, developing biodiesel regulations/policies, funding biodiesel research initiatives, etc. Overall, biodiesel could be a way better solution to supplant diesel with renewable fuel. We believe that the data presented in this report will shed light on Ethiopia's current and future prospects for biodiesel deployment.
... Microalgae have high biomass and lipid productivity compared to other biomasses (Chisti, 2007;Han et al., 2011), and some species have lipid contents constituting about 50%-60% of their dry weight (Jones and Mayfield, 2012). Algae are capable of yielding more biofuel than other feedstocks per unit of growing area (Gao et al., 2012;Scott et al., 2010). A proposed process of producing biofuels from algae involves cultivating algae in large ponds and adding nutrients in ways that enhance lipid production, harvesting and extracting lipids, and converting lipids into biodiesel through transesterification (Sauli and Sarbatly, 2012). ...
Algae lipids can be used to produce biofuels and are considered a potential source of energy to supplant fossil fuel. Cultivation practices of algae grown in large ponds can be tailored to maximize lipid content. Laboratory methods of measuring lipid content are time-consuming and labor-intensive, so a real-time measuring technique is needed to efficiently control the addition of pond nutrients. The objective of this research was to determine the effectiveness of measuring algae lipid content with Fourier Transform Infrared (FTIR) transmission spectroscopy. Six algae samples (Nannochloropsis salina) with varying lipid contents were centrifuged and then dried in an oven at 40° C for 12 hours. Dried algae were mixed with potassium bromide (KBr) powder at a mass ratio of 1:150 (algae: KBr) and pressed into pellets. A Thermo-Nicolet 6700 FTIR spectrometer was used to collect spectral data in transmission mode. Three relevant absorption bands centered at 2920, 2855, and 1742 cm-1 were identified. A linear regression analysis showed that the band depth at 2920 cm-1 was strongly correlated (R 2 = 0.92) with lipid content measured by gas chromatography (GC). The results of this research provide insight into the development of a real-time lipid-content sensor.
... Various aquatic algae, organic feedstocks, and including terrestrial are being used to produce green energy for fossil substitution [1]. It is used as a sustainable carbon-neutral type of fuel because of its range and rapid yield [2,3]. Microalgae are species of microscopic that are guided by the same mechanism and typically suspended as high plants e.g. ...
With rising fuel demands, the carbon which is avowed as inefficient energy sources is continually declining. This method is a promiscuous way not of lowering CO2 emissions but of producing economic benefits. The physiochemical conversion of carbon dioxide into chemical (energy) goods without contamination. The production of microalgae will thus help to repair CO2 and biofuels sources. In this present work, we have done a comprehensive reviewed in this paper that carbon dioxide capture mechanism, contribution of microalgae for biomass production. As a result of using microalgae (S. platensis, Salmeriensis, and Scenedesmus dimorphus are capture maximum CO2 respectively of 1.00 and 0.81gL−1 d−1, 1.0gL−1day−1-2.8gL−1day−1 and 0.8g CO2 L−1d−1 with the production of microalgae biomass (<0.4g L-1day-1, 129.24 mg−1d−1, and 0.44gcel L−1d−1) in wastewater. The overall cost of the process is considerably reduced when these light conversion and chemical processes are combined, making carbon dioxide collection even more economically viable. Microalgae was used on extensively for biodiesel production and carbon dioxide reduction, and the processes were significantly enhanced with the use of microalgae. To conclude microalgae holds a strong promise in the 21st-century biofuel industry and environmentally friendly by capturing CO2. GUB JOURNAL OF SCIENCE AND ENGINEERING, Vol 8, Dec 2021 P 29-35
... There is an increased interest among researchers to search for alternative fuels due to harmful emissions, high costs of petroleum products, and the uncertainty of future petroleum supplies [1]. Biodiesel is an alternative fuel that can overcome these challenges [2], requiring less energy to produce, thus having a higher net energy, even though the outputs of petroleum-based and biomass-based diesel are similar [3]. While oleaginous crops, e.g., soy and canola, are excellent feedstocks for biodiesel production, it is generally not a good strategy to use economicallyimportant edible plants for energy sources. ...
The economic feasibility of growing Nannochloropsis sp. at the commercial scale was evaluated for the production of biodiesel and co-products. A local isolate of Nannochoropsis was grown in (6) 200-L raceway ponds at Alexandria University wherein cultures reached maximum cell concentrations ~ 4–6 × 107 cells/mL (0.63–0.88 g/L dry weight) and a peak biomass productivity of 0.09 g/L/day during mid- to late-log growth. Areal productivity was estimated at 17.65 g/m2/day when ponds were operated on a semi-batch schedule, harvesting 50% every 2 days and recycling 60% of the media. Areal productivity was estimated around 10.3 g/m2/day for batch schedules. Late-log cultures harvested from all ponds yielded 10 kg of wet algal paste, which was reduced to 1.05 kg of dried algal powder. The biomass was composed of valuable co-products approx. 14.0% carbohydrate, 37.3% protein, 0.01% chlorophyll-a, and 0.02% carotenoids (w/w). Total lipid made up 38% of the biomass (w/w); 34% of the biomass was determined to be neutral lipid which are transesterified to biodiesel and 4% are polar lipid. Fatty acids from glycerolipids were quantified by gas chromatography-flame-ionization detector (GC-FID) as fatty acid methyl esters (FAMEs) revealing carbon-chain lengths from C6 to C22. A preliminary economic evaluation was conducted to determine the feasibility of constructing commercial-scale algae biodiesel production facilities in Egypt. The return on investment (ROI) of the current economic feasibility study for biofuel production alone was 22% after considering the market prices of the biodiesel, cake, and glycerol by-products. Based on this assessment, additional high-value products are needed to improve the ROI. Noting that the valuable co-products are considered as added cost in the biomass left after biodiesel production.
... У процесу гајења алги незнатан је утицај на биосферу, а током животног циклуса оне усвоје велике количине угљен-диоксида из атмосфере. Произведена биомаса се користи за добијање течних биогорива (Gao et al., 2012). Поред тога, алге могу бити значајан извор антиоксиданаса, пигмената и природних боја, који се лако могу добити познатим технолошким поступцима (Tokuşoglu and Uunal, 2003). ...
FOREWORD
The book High Grasses by the authors Djorđe Glamočlija, Nenad Djurić and Jelena Maksimović deals with questions of botanical affiliation, biological characteristics, origin, economic significance, relationship with growing conditions and agrotechnics, of five plant species from the Poaceae family belonging to the group of wild perennial tall grasses. Discovering their favorable biological characteristics and the possibility of use in various industries, as well as in nutrition of domestic animals and for food preparation, by applying modern selection methods, scientists have created a large number of genotypes that can be grown in different agorecological conditions.
A study of the relationship between the described five species of tall grasses and agroecological conditions, and by comparing them with the conditions of agricultural areas in Serbia, shows that these plants can successfully be grown in our country. Their introduction into the system of regular plant production is a great chance for agricultural areas with lands having less favorable physical and chemical properties. The described tall grasses can be grown on the most fertile as well as on marginal lands, unsuitable for field-vegetable and fruit-vineyard production. The introduction into production of these perennial plants, with increased investments in the year of establishment, that become significantly lower in the years of use, could enable utilization of uncultivated agricultural land, but also the repurposing for use of a majority of non-agricultural, degraded areas and of deposol. The annual yield of tall grass biomass would to a significant extent meet the needs of various industries, as well as the needs of domestic animals in fodder and concentrates. The main products of the latest genotypes of certain species (interspecies hybrids) are interesting as raw materials in the food and pharmaceutical industries.
The most important way to use the biomass of these grasses is for producing gaseous liquid and solid biofuels. Replacing fossil fuels with biofuels achieves significant effects. Our country, which has to import large quantities of fossil fuels, would reduce its dependence on imports. From the ecological point of view, it is important to point out thatcombustion of biofuels releases significantly smaller amounts of harmful gases into the atmosphere, which mitigates the rise in temperature due to the greenhouse effect. All five types of tall grasses described in the monograph could be grown as energy crops.
A regional comparison of the relationship between agroecological conditions of each of the described tall grasses with the characteristics of our agricultural areas, could enable regionalization to be performed on the territory of the Republic, from lowlands to hilly and mountainous areas, and also from wetter to arid landscapes. The technology of production and storage of raw materials until further processing are described in detail for each of the species.
Climatic and soil conditions of our country are favorable for growing the described tall grasses, which is a great chance for small farmers, where with standard agricultural mechanization and a higher share of manual labor, this would enable more complete engagement of all household members. With a somewhat higher investment in the year of establishment, but also in primary processing of the main and of secondary products, the farmer is able to make big profits by growing these little-known plants that thrive on poorer and uncultivated soils.
The monograph is written in an easy style so that it can serve as a textbook for students, future agricultural experts, but also as a good source of useful information for all current and future producers of these little known plants with great production potential.
Smederevska Palanka, june, 2022. AUTHOR
... The conventional microalgae production system includes i) cultivation; ii) harvesting; iii) pre-treatment; iv) transesterification; v) purification. Microalgae cultivation utilises open ponds [27,28] or enclosed photobioreactors [29], while recent interests are towards attached biofilm cultivation [30,31]. Once the microalgae are grown, the cells are harvested using different cell concentration techniques such as centrifugation, gravity sedimentation, filtration, floatation and flocculation [32], which are energy intensive techniques requiring higher energy. ...
Life cycle assessment (LCA) entails the analysis of potential environmental loads and natural resources utilised while manufacturing a product, which helps in sustainable production of biofuel and prudent management of natural resources. A variety of bio resources including microalgae are being explored for its potential as viable alternatives to conventional fossil fuels. This communication presents the lifecycle assessment of biodiesel production from microalgae and valorisation of other value-added products. Comparative assessment of feed-stock cultivation was done by considering varied nutrient inputs-(i) no nutrient input (scenario 1), (ii) wastewater as nutrient input (scenario 2) and (iii) fertiliser input (scenario 3). Two different transesterification techniques followed for converting microalgal oil into biodiesel were i) acid catalyst and ii) biocatalyst. Environmental impacts of different scenarios considered were assessed using OpenLCA v1.10.3, which highlights higher eutrophication and photochemical oxidation related emissions for fertiliser input scenario with acid catalyst based transesterification. However, significant reductions in environmental impacts with minimal GHG footprint was observed with wastewater use for cultivating algae and transesterification through biocatalyst. Life cycle assessment of three different scenarios revealed a fossil energy requirement variation between 3.6 and 5.7 MJ/kg and the greenhouse gas emission (as kg equivalent CO 2 emissions) of 0.85-1.46 kg CO 2eq .kg − 1 of biodiesel. This highlights a reduction in fossil energy requirement of about 87.3% in the pilot substrate-based microalgal bioreactor. Wastewater-biocatalyst scenario exhibited a highest net energy ratio (NER) of 18.8 with an additional benefit of low cost remediation of wastewater.
... In 2006 Canadian federal government opens a strategy on renewable fuels with the following four aspects: to support the expansion of renewable fuel production in Canada, increasing biofuel availability, accelerating the opportunities in biofuel industries, and commercialization of the new biofuel technologies (O'Connor 2011). In 2006, the Canadian federal government showed its attentiveness by introducing the Alternative Fuel Act 2006 to encourage biofuel technology and industries and make a commitment to increase its purchase power (Gao et al. 2012 ...
Desires of living a higher standard of life bring regular consumption of
non-renewable energy resources. This conventional fuel consumption causes emis-
sion of CO2, particulate matter, and greenhouse gases to the atmosphere; in such
conditions, energy crisis brings ignited focus on algaculture for producing biodiesel
and other liquid biofuels. Algal oil or algal biofuels are third-generation biofuels,
emerged as a renewable alternative to conventional liquid fuels. These algal oils are
also a replacement for conventional biofuels, which are obtained from agricultural
sources like corn, sugarcane, oilseed plants, and some animal fats. Unlike oilseed
crops, they do not need vast farmland and hence keep agrarian lands available for
food crops. Algaculture is possible in freshwater, saline water, and wastewater from
various sources with minimal impact. Algaculture has a significant effect on envi-
ronmental pollution as it assimilates nitrate and phosphate present in wastewater
while continuously contributing to CO2 sequestration. Algal oils are biodegradable
and comparatively less harmful to the surrounding if spilled. Open outdoor cultures
are used for algae cultivation for their low cost, but generally, they are profoundly
affected by environmental disturbances like light availability and temperature
swings. Ongoing research in algal biofuels is focused on the rapid growth of
biomass, high lipid production, and thermal tolerance.
