scholarly journals Microalgal Production of Biofuels Integrated with Wastewater Treatment

2021 ◽  
Vol 13 (16) ◽  
pp. 8797
Author(s):  
Merrylin Jayaseelan ◽  
Mohamed Usman ◽  
Adishkumar Somanathan ◽  
Sivashanmugam Palani ◽  
Gunasekaran Muniappan ◽  
...  

Human civilization will need to reduce its impacts on air and water quality and reduce its use of fossil fuels in order to advance towards a more sustainable future. Using microalgae to treat wastewater as well as simultaneously produce biofuels is one of the approaches for a sustainable future. The manufacture of biofuels from microalgae is one of the next-generation biofuel solutions that has recently received a lot of interest, as it can remove nutrients from the wastewater whilst capturing carbon dioxide from the atmosphere. The resulting biomass are employed to generate biofuels, which can run fuel cell vehicles of zero emission, power combustion engines and power plants. By cultivating microalgae in wastewater, eutrophication can be prevented, thereby enhancing the quality of the effluent. Thus, by combining wastewater treatment and biofuel production, the cost of the biofuels, as well as the environmental hazards, can be minimized, as there is a supply of free and already available nutrients and water. In this article, the steps involved to generate the various biofuels through microalgae are detailed.

Energy Policy ◽  
2009 ◽  
Vol 37 (2) ◽  
pp. 669-679 ◽  
Author(s):  
Andreas Poullikkas ◽  
Ioannis Hadjipaschalis ◽  
Costas Christou

1981 ◽  
Vol 38 (5) ◽  
pp. 591-624 ◽  
Author(s):  
David M. Rosenberg ◽  
Vincent H. Resh ◽  
Steven S. Balling ◽  
Mark A. Barnby ◽  
Joshua N. Collins ◽  
...  

The objectives of this paper are to characterize an "ideal" environmental impact assessment (e.i.a.); to review the contemporary status of e.i.a. for several major activities and areas of development; and to identify successes, failures, and future needs in e.i.a.The institutional procedures to be followed for e.i.a. have been formalized in a number of countries, but the scientific basis and methods are still developing. We propose that the following elements comprise an ideal e.i.a.: (1) definition of scientific objectives, (2) background preparation, (3) identification of main impacts, (4) prediction of effects, (5) formulation of usable recommendations, (6) monitoring and assessment, (7) sufficient lead time, (8) public participation, (9) adequate funding, and (10) evidence that recommendations were used.The "best available" predictive, preoperational e.i.a.'s involving aquatic resources (power plants, fossil fuels, recreation, reservoirs, wastewater treatment, forestry, and dredging and water diversion in estuaries) were reviewed and scored on a 0–5 scale for each of the elements identified above. Mean scores for the criteria which could be assessed (nos. 1–8) indicated that the quality of the best available e.i.a.'s does not exceed our defined average but improves when legally required documents are excluded from the calculations. The lowest means, for criteria within the scientist's control (nos. 1–5), were obtained for "Prediction of effects" and ' "Formulation of usable recommendations." Overall mean scores for each development area (criteria 1–5) indicated three broad groups which included studies of above average quality (wastewater treatment, recreation); studies of approximately average quality (estuarine impacts, power plants, reservoirs, and fossil fuels); and studies of below average quality (forestry practices).Environmental impact assessment has had the following successes: increased environmental awareness due to public involvement in e.i.a., some environmental protection, and elucidation of intriguing research problems. The list of failures of e.i.a. is, however, longer: "tokenism," unrealistic time constraints, uncertainty of program or development schedules, difficult access to e.i.a. literature, questionable ethics, lack of coordination among studies, and poor research design.Future organizational/administrative needs of e.i.a. include improved access to e.i.a. literature, increased accountability for e.i.a.'s and their authors, improved public input into project decisions and designs, and improved organization and presentation of e.i.a. reports. Future scientific/research needs include development of methods to define and quantify relationships between biological, esthetic, and economic impacts; support for independent biological inventory programs; adequate time frames; improved design of research; inclusion of monitoring and assessment in every e.i.a.; study of cumulative impacts on a regional or national scale; and improved communication between scientists and planners.Key words: environmental impact assessment, aquatic ecology, power plants, fossil fuels, recreation, reservoirs, wastewater treatment, forestry, dredging and water diversion (estuaries)


Author(s):  
Nela Slavu ◽  
Cristian Dinca

Abstract One of the way to reduce the greenhouses gases emissions generated by the fossil fuels combustion consists in the Carbon Capture, Transport and Storage (CCS) technologies utilization. The integration of CCS technologies in the coal fired power plants increases the cost of the energy generation. The CCS technology could be a feasible solution in the case of a high value of a CO2 certificate but for the present value an optimization of the CCS technology integration in the power plants is expected. However, for reducing the cost of the energy generated in the case of CCS integration in the power plants, a parametrical study optimization of the CO2 capture process is required. In this study, the chemical absorption process was used and the monoethanolamine with 30 wt. %. The objective of this paper is to analyze the effects of the package type used in the absorption column on the size of the equipment used and, on the energy cost of the power plant with CO2 capture process consequently. The packages types analyzed in this paper are metal Pall rings with different sizes and the rings are made of different metals: aluminum, nickel, cooper, and brass. In the case of metal Pall rings, the utilization of different material has an impact on the absorption column weight. Also, Pall rings made of plastics (polypropylene and polyethylene) were analyzed. The comparative assessment was achieved for a coal fired power plant with an installed power of 100 MW and considering the CO2 capture process efficiency of 90 %.


2015 ◽  
Vol 10 (2) ◽  
pp. 414-421
Author(s):  
Bahareh Hashemlou ◽  
Hossein Sadeghi ◽  
Arashk Masaeli ◽  
Mohammadhadi Hajian ◽  
Shima Javaheri

Organizations, institutions, and different sectors of manufacturing, services and agriculture are constantly making decisions. Each of the aforementioned sectors, have strategies, tactics, and various functions that play a basic role in reaching the objectives. On the other hand, energy demand in developing countries is increasing day by day. The exact calculation of the cost per unit of electricity generated by power plants is not easy. Therefore, this study according to four sources of natural gas, nuclear energy, renewable energy and other fossil fuels other than natural gas that are used in a variety of electricity production plants is trying to clarify the ranking of generation electricity approach using "fuzzy preference relations" analysis. Accordingly, three models were used and the results showed that natural gas, with regard to the four criteria of low investment cost, low power, lack of pollution and the safety and reliability of electrical energy has priority over other alternatives. Full preferred model results also suggested that the energy of natural gas, renewable energies, nuclear and other fossil fuels should be considered in a priority for power generation. Sensitivity analysis results moreover demonstrated that the above models are not affected by the threshold values ​​and the full stability of the models is observed.


Author(s):  
Luigi De Paoli ◽  
Francesco Gulli

- The debate on the benefits of nuclear energy revolves around the very competitiveness of this energy source. This article tries to show why it is not easy to answer unambiguously the question whether or not it is convenient to resort to nuclear power in a given country. After listing the factors on which the cost of electricity generation rests and discussing the range of probability of their value, the levelized cost of electricity generation from nuclear, coal and gas-fired plants is calculated using the Monte Carlo method. The results show that nuclear power is likely to be competitive, especially if policies to combat CO2 emissions will continue in the coming decades. There are, however, some margins of uncertainty, mainly related, to the one hand, to the cost of nuclear plants, that depends on the socio-institutional context, and on the other, to the fossil fuels cost, that are inherently difficult to anticipate even on average. Finally it is noted that the context of liberalized electricity markets may make it more difficult for investors to accept the risk of investing in nuclear power plants and for the community to socialize some of the costs associated with this technology.Key words: Nuclear energy, generation costs, Montecarlo method, environmental impacts.JEL classifications: G11, H23, L72, L94, Q31, Q40


2020 ◽  
Vol 2 (1) ◽  
pp. 17
Author(s):  
Woojong Jung

<p align="justify">After the Fukushima nuclear power plant accident, Japan had an opportunity to advance its economic and energy policies to pursue stable energy supply, economic efficiency, environmental security, and safety. The accident not only raised concerns regarding the safety of nuclear power plants but also increased awareness regarding the effect of energy import growth on the economy and related issues such as the effect of imports on Japan’s international competitiveness. This study simulates the impact on electricity prices using three potential scenarios for Japan. According to the results, the consumer price index (CPI) was larger than the corporate goods price index (CGPI) for Japan in all cases. In the simulation results, the CPI was observed to have an increased effect of 0.88%–3.59% against a 0.84%–3.41% increase in the CGPI. The surge in electricity prices significantly impacted the supply of electricity, gas, and heating and also the business services sector. The cost of policies that maintain safety, the increase in costs resulting from the overseas importation of fossil fuels, and the cost of promoting renewable energy in conjunction with the reutilization of nuclear power plants leading to higher electricity prices will also be considered in the future.</p>


2019 ◽  
Vol 4 (4) ◽  
pp. 329-337
Author(s):  
Mária Ambrus ◽  
Roland Szabó ◽  
Gábor Mucsi

Over the past decades, both the residential and industrial energy demand has increased due to the continuously growing consumption and production. As a large share of the electricity is still produced using fossil fuels, the utilisation of the by-products is a contemporary and pervasive issue. Fly ash is generated in large quantities in coal-fired power plants and has been proven to be an appropriate raw material for various industrial uses. Among others, it is applicable as an additive and lightweight aggregate in the cement and concrete industry, can be used for CO2 sequestration, glass foam production, catalyst production, or as a base material for geopolymers, as well. Geopolymers are inorganic polymers produced via the reaction between solid alumina and silica containing or alkali silicate materials in alkali media. Due to their numerous advantageous properties and wide variety of utilisation possibilities, research on fly ash base geopolymers became widespread topic. The quality of fly ash is determined by technical requirements, and the degree of quality control requirements depends on the final use. In certain fields of applications, standards and regulations have already been created to ensure the consistent quality of the final products made from fly ash, e.g. in the cement and concrete industry. There are various methods for fly ash processing, however, the methods to achieve the necessary properties are not standardised.


2013 ◽  
Vol 12 (4) ◽  
pp. 374-383 ◽  

Global warming is one of the most serious challenges facing humankind as it has the potential to dramatically modify the living conditions of future generations. In order to reduce the emission of greenhouse gases, most countries are implementing regulations aimed at reducing their dependence on fossil fuels, promoting energy efficiency practices and favoring the deployment of low carbon energy technologies, including renewable energy sources. In line with the international commitments assumed as a member of the European Union (EU) and also as a signatory of the Kyoto Protocol, Spain developed a National Plan for Renewable Energies (PER 2005-2010) that forms the basis of the national strategy in this field. Spain has often been cited as an example for the rapid growth in the use of low carbon energy technologies. However, despite significant progress in the last decade, Spain is far from meeting the national objectives set in PER primarily due to slow growth in the demand for biofuels and the limited success of biomass fired power plants. The evolution in other energy technologies has been faster, situating Spain as world a leader in solar and wind energy. However, the contribution of these technologies to the national consumption is very marginal. In the midst of intense regulatory, commercial and R&D activity, this paper analyses the current situation with respect to the production of renewable energies in Spain, focusing primarily on the use of biomass resources. The paper offers a general view of policy and regulatory background, illustrates current progress towards meeting national objectives and provides a brief description of representative projects and market activity in biofuel production and biomass valorization.


Author(s):  
Vaclav Smil

Energy is the only universal currency; it is necessary for getting anything done. The conversion of energy on Earth ranges from terra-forming forces of plate tectonics to cumulative erosive effects of raindrops. Life on Earth depends on the photosynthetic conversion of solar energy into plant biomass. Humans have come to rely on many more energy flows—ranging from fossil fuels to photovoltaic generation of electricity—for their civilized existence. This book provides a comprehensive account of how energy has shaped society, from pre-agricultural foraging societies through today’s fossil fuel-driven civilization. Humans are the only species that can systematically harness energies outside their bodies, using the power of their intellect and an enormous variety of artifacts—from the simplest tools to internal combustion engines and nuclear reactors. The epochal transition to fossil fuels affected everything: agriculture, industry, transportation, weapons, communication, economics, urbanization, quality of life, politics, and the environment. This book describes humanity’s energy eras in panoramic and interdisciplinary fashion, offering readers a magisterial overview.


Sign in / Sign up

Export Citation Format

Share Document