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Petroleum Geochemical Survey
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
Ocean water contains more dissolved salts (ionic form) compared to river water as evident from the fact that total dissolved solids in sea water are about 3.5% , whereas the dissolved solids in river water is much lower, compared to sea water, from 0.001 to 0.5.0 % depending on the geographical location. The major dissolved salts in sea water are of sodium (30.5%), potassium (2.0%), magnesium (3.5%) and calcium (1.2%) elements; in addition to these, there are more than 100 dissolved salts found in the ocean in trace quantities. Ocean water is termed ‘brackish or salty’ water. In spite of water exposure and interaction with the earth’s atmosphere, crust and different water sources, the chemical composition of ocean water is almost constant. The composition does change appreciably; it has the capability to maintain the balance through its own processes of transferring ionic constituents among different sources.
Environmental Biotechnology
Published in Firdos Alam Khan, Biotechnology Fundamentals, 2020
Approximately 71% of the earth’s surface (an area of some 361 million square kilometers) is covered by oceans, a continuous body of water that is customarily divided into several principal oceans and smaller seas. More than half of this area is over 3000 meters deep. Average oceanic salinity is around 35 parts per thousand (ppt) (3.5%), and nearly all seawater has a salinity in the range of 30–38 ppt. Though generally recognized as several “separate” oceans, these waters comprise one global interconnected body of salt water, often referred to as the World Ocean or global ocean. This concept of a global ocean as a continuous body of water with relatively free interchange among its parts is of fundamental importance to oceanography. The major oceanic divisions are defined in part by the continents, various archipelagos, and other criteria. These divisions are (in descending order of size) the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, the Southern Ocean (which is sometimes subsumed as the southern portions of the Pacific, Atlantic, and Indian Oceans), and the Arctic Ocean (which is sometimes considered a sea of the Atlantic). The Pacific and the Atlantic oceans may be further subdivided by the equator into northern and southern portions. Smaller regions of the oceans are called seas, gulfs, bays, and other names. There are also salt lakes, which are smaller bodies of landlocked saltwater that are not interconnected with the World Ocean. Two notable examples of salt lakes are the Aral Sea and the Great Salt Lake.
Electrospun Nanofibrous Membranes for Membrane Distillation Process
Published in Ahmad Fauzi Ismail, Nidal Hilal, Juhana Jaafar, Chris J. Wright, Nanofiber Membranes for Medical, Environmental, and Energy Applications, 2019
Mohammad Mahdi A. Shirazi, Morteza Asghari
All these issues have led to a critical and global alarm for the availability of fresh water resources. Therefore, the need for technological innovation to enable novel water management cannot be ignored. A solution for this global challenge is Desalination. Desalination is a process for producing fresh water from a saline source such as seawater (Gillam and McCoy, 1967). Seawater is desalinated to produce water suitable for human consumption, irrigation or animal watering. It is worth noting that the modern interest in desalination is mostly focused on cost-effective and highly efficient provision of fresh water for human use (Matsuura, 2001; Fane, 2018). Nanotechnology holds great potential in advancing desalination to improve the efficiency of salt and impurities removal to supply water via safe use of unconventional water resources (Qu et al., 2013; Lu and Astruc, 2018). In this regard, electrospinning technology is an emerging and versatile technique for fabricating micro- and nanofibers, which can be used for desalination and water treatment purposes. This chapter will discuss the application of electrospun nanofibers for desalination and water treatment using membrane distillation processes, by examining the fundamental concepts of this technology, its operating principles and the future perspectives.
Experimental study and economic cost analysis about enhancement productivity for a conventional solar still combined with humidifiers ultrasonic
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Naseer T. Alwan, S. E. Shcheklein, Obed M. Ali
On our planet, fresh-water makes up 2.5% of earth’s water. Although the surface of the earth is covered by water by 70%. In general, seawater contains salinity levels ranging from 3500 to 4,500 ppm. According to data from World Health Organization, Acceptable proportions of dissolved salt in drinking water should generally not exceed 500 parts per million and 1,000 parts per million for especially cases (Tiwari, Singh, and Tripathi 2003). So, it is impossible to use seawater directly for human, agricultural and industrial uses. Many countries in the world still depend on seawater as a potable water source after the desalination process (Khawaji, Kutubkhanah, and Wie 2008). The average daily production of drinking water from the traditional desalination process worldwide is about (García-Rodríguez 2002). However, this production process consumes large amounts of fossil fuels. According to estimates, it is necessary to burn approximately 130 million tons of oil annually to produce 13000000 (Muhammad-Sukki et al. 2012).
Copernicus Marine Service Ocean State Report, Issue 4
Published in Journal of Operational Oceanography, 2020
Karina von Schuckmann, Pierre-Yves Le Traon, Neville Smith, Ananda Pascual, Samuel Djavidnia, Jean-Pierre Gattuso, Marilaure Grégoire, Glenn Nolan, Signe Aaboe, Enrique Álvarez Fanjul, Lotfi Aouf, Roland Aznar, T. H. Badewien, Arno Behrens, Maristella Berta, Laurent Bertino, Jeremy Blackford, Giorgio Bolzon, Federica Borile, Marine Bretagnon, Robert J.W. Brewin, Donata Canu, Paola Cessi, Stefano Ciavatta, Bertrand Chapron, Thi Tuyet Trang Chau, Frédéric Chevallier, Boriana Chtirkova, Stefania Ciliberti, James R. Clark, Emanuela Clementi, Clément Combot, Eric Comerma, Anna Conchon, Giovanni Coppini, Lorenzo Corgnati, Gianpiero Cossarini, Sophie Cravatte, Marta de Alfonso, Clément de Boyer Montégut, Christian De Lera Fernández, Francisco Javier de los Santos, Anna Denvil-Sommer, Álvaro de Pascual Collar, Paulo Alonso Lourenco Dias Nunes, Valeria Di Biagio, Massimiliano Drudi, Owen Embury, Pierpaolo Falco, Odile Fanton d’Andon, Luis Ferrer, David Ford, H. Freund, Manuel García León, Marcos García Sotillo, José María García-Valdecasas, Philippe Garnesson, Gilles Garric, Florent Gasparin, Marion Gehlen, Ana Genua-Olmedo, Gerhard Geyer, Andrea Ghermandi, Simon A. Good, Jérôme Gourrion, Eric Greiner, Annalisa Griffa, Manuel González, Annalisa Griffa, Ismael Hernández-Carrasco, Stéphane Isoard, John J. Kennedy, Susan Kay, Anton Korosov, Kaari Laanemäe, Peter E. Land, Thomas Lavergne, Paolo Lazzari, Jean-François Legeais, Benedicte Lemieux, Bruno Levier, William Llovel, Vladyslav Lyubartsev, Pierre-Yves Le Traon, Vidar S. Lien, Leonardo Lima, Pablo Lorente, Julien Mader, Marcello G. Magaldi, Ilja Maljutenko, Antoine Mangin, Carlo Mantovani, Veselka Marinova, Simona Masina, Elena Mauri, J. Meyerjürgens, Alexandre Mignot, Robert McEwan, Carlos Mejia, Angélique Melet, Milena Menna, Benoît Meyssignac, Alexis Mouche, Baptiste Mourre, Malte Müller, Giulio Notarstefano, Alejandro Orfila, Silvia Pardo, Elisaveta Peneva, Begoña Pérez-Gómez, Coralie Perruche, Monika Peterlin, Pierre-Marie Poulain, Nadia Pinardi, Yves Quilfen, Urmas Raudsepp, Richard Renshaw, Adèle Révelard, Emma Reyes-Reyes, M. Ricker, Pablo Rodríguez-Rubio, Paz Rotllán, Eva Royo Gelabert, Anna Rubio, Inmaculada Ruiz-Parrado, Shubha Sathyendranath, Jun She, Karina von Schuckmann, Cosimo Solidoro, Emil V. Stanev, Joanna Staneva, Andrea Storto, Jian Su, Tayebeh Tajalli Bakhsh, Gavin H. Tilstone, Joaquín Tintoré, Cristina Toledano, Jean Tournadre, Benoit Tranchant, Rivo Uiboupin, Arnaud Valcarcel, Nadezhda Valcheva, Nathalie Verbrugge, Mathieu Vrac, J.-O. Wolff, Enrico Zambianchi, O. Zielinski, Ann-Sofie Zinck, Serena Zunino
The ocean mitigates thus global warming by taking up excess CO2 (or anthropogenic C) emitted to the atmosphere, a ‘service’ that comes at the cost of profoundly modifying seawater chemistry. Carbon dioxide is a weak acid that reacts with water in a suite of reactions consuming carbonate ions (CO32–) and releasing hydrogen ions (H+). The increase in H+ corresponds to an increase in acidity (ocean acidification), generally measured as a decrease in pH (pH = - log [H+]). The average pH of surface ocean seawater has already deceased by 0.1 pH unit (26% increase the concentration of H+) since 1870–1899 (Gattuso et al. 2015). Many biological processes depend on a tight regulation of pH at the cellular level and mechanisms of pH regulation are present across many taxa (Seibel and Walsh 2001). Ocean acidification occurs together with warming, loss of oxygen and changes in nutrient availability for marine primary production (Bopp et al. 2013), and it constitutes a threat to marine organisms, including species of commercial value (e.g. shell fish), ecosystems and dependent services (Hilmi et al. 2013; Gattuso et al. 2015).
Effect of salinity on rheological and strength properties of cement-stabilized clay minerals
Published in Marine Georesources & Geotechnology, 2020
Jie Yin, Ming-ming Hu, Gui-zhong Xu, Wen-xia Han, Yong-hong Miao
Results from this study indicate that the presence of sodium salt (NaCl) decreases the Atterberg limits and viscosity parameters and increases the flowability of groups of clays: illite, kaolinite and montmorillonite. Similar results may be expected for other naturally occurring salt (non-sodium salt). As we know, the most abundant dissolved ions in seawater are sodium, chloride, magnesium, sulfate, calcium and potassium. The type of exchangeable cations influence the thickness of the particles. Divalent and polyvalent cations lead to larger particles. The CEC decreases in the order Ca2+>Mg2+>K+>Na+. The presence of salt has an adverse effect on the strength acquisition with cement-stabilized clay minerals. Moreover, the CEC of illite is smaller than that of montmorillonite but higher than that of kaolinite due to the differences in clay mineralogy. It is evident that the changing clay minerals properties will have a significant impact on the engineering properties of clayey soils. Therefore, the findings concluded in the study will give a better understanding of rheological and strength properties of cement-stabilized dredged clays in coastal areas since the negative impact of porewater salt should not be neglected in engineering practice.