Hydrogen owing to its abundance in universe is replacing the fossil energy sources like coal, petroleum etc that are being depleted speedily. Hydrogen is energetic per unit mass of fuel burned i.e. 120.7 kJ/g compared to any type of fuel (Haryanto et al., 2005). Moreover, fossil sources produce pollutants like COx, NOx, SOx, CxHx, soot, ash and other organic compounds to the atmosphere on burning that adds to the global warming. Hydrogen was discovered by Henry Cavendish in 1766 and named in 1783 by Antoine Lavoisier with origin of name from words "hydro" and "genes" meaning "water" and "generator" because it burns to produce water only (Song, 2003). It is present in combination to the other elements like with oxygen in water, with carbon in hydrocarbons and need to be extracted. Other sources can be a variety of fossil and non-fossil resources like coal, natural gas, liquefied petroleum gas, diesel, biomass and its derived fuels such as methanol, ethanol, and biodiesel (Haryanto et al., 2005).
Hydrogen fuel cells are used to provide energy for transport and mobile applications in form of electricity directly from chemical energy to power laptops, vehicles or other applications where cost is not a big issue like space technology, submarines etc. They are energy efficient, clean, fuel flexible, not noisy, vibrations are not there and they have smooth operation resulting in comfort of the users (Silveira et al., 2009). Moreover, fuel used in fuel cells has greater energy density than batteries (Park et al., 2007) which is required for portable applications like laptops, medical and telecommunication devices and for military applications like remote sensors (<20W), silent power generation and battery recharging (200W- 2kW) and mobil...
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...ry method of removal or addition of convective heat). So, the final "success" of this technology will depend largely on modeling, understanding and control of temperature excursions.
In this work, ethanol is steam reformed in a non-isothermal tubular reactor which is coupled with ethanol combustion in recuperative way where heat is transferred from the exothermic reaction zone through the walls of channel. A full three-dimensional geometry is modeled consisting of co-flow and counter-flow configurations. The authors have studied the design configurations based on ethanol steam reforming through one dimensional models and experiments (Table 2) but a 3-D model was required in order to fully explore the various transport processes in the configurations and study the variations in the reactor performance due to hydrodynamics and heat and mass transfer characteristics.
Hydrogen is a diatomic element that is in a gaseous form at room temperature. Its most identifying characteristic is the fact that it is highly explosive. It is the lightest element in the world, and has a lifting power of 8% more than that of helium. Hydrogen was used in airships and zeppelins for more than 20 years during the beginning of the 20th century. This practice stopped abruptly after the German airship Hindenburg disaster over New Jersey. It is used in fuel cells to create electricity, and to power cars and planes. Liquid hydrogen is mixed with liquid oxygen to form a cryogenic liquid that is burnt in Solid Rocket Boosters to power the space shuttle. Hydrogen is used to fill weather balloons because of its superb lifting power.
To complete the vapor velocity vs. HETP relationship, the vapor velocity must be found. The vapor velocity was found using a system energy balance. The design vapor velocity was determined to be 4.85 ft/hr. However, this vapor velocity did not result in the column flooding; therefore the scaled-up column is not designed to its full potential. Ideally, distillation columns should be designed at 70-80% of the flooding velocity. The column HETP was found by use of the Fenske equation and was determined to be an average of 4.55 inches.
Hydrogen lies in one of the copious replacements for gasoline. It is not an energy source such as oil, but an energy carrier that is produced instead of digging and finding it underground. Though replacing fossil fuels by hydrogen fuel cell is very hard and costs a great deal, for the most part, hydrogen fuel cell is a zero carbon emission fuel which highly reduces the carbon emissions that causes pandemic global warming. Hydrogen is very helpful for nature by cause of replacing fossil fuels with hydrogen fuel cells might end global warming once and for all.
The earth’s supply of gasoline is slowly diminishing along with the cleanliness. In a desperate attempt to save precious gas, scientists have been attempting to find new ways to store and use energy. One way that scientists are consistently trying out is storing hydrogen. According to Demirbas(2001), “Because hydrogen can be easily generated from renewable energy sources and water, it has great potential as an energy source” (p. 287). When using hydrogen, the product leads to zero emissions (Yocular & Olgun, 2008, p. 309). If not that, then carbon-free or carbon neutral systems are formed (Yocular and Olgun, 2008, p. 309). Alternative-energy researchers have attempted to find materials that have properties that can resemble those of sponges (Baker, 2005, p.82). This way, the materials could ‘soak in’ the hydrogen and then hold it until it is further needed (Baker, 2005, p.82). There are many ways of storing hydrogen, but what is the most effective way to store it?
In conclusion, hydrogen is one of the many important elements on the periodic table. Hydrogen makes up 2/3 of water, 1/4 of the air, 0.15% of the earth's crust, metal hydrides found in some batteries, and in many carbohydrates we eat. Hydrogen serves as many sources of fuel, such as fuel for most starts to produce energy or for rockets. Due to how useful this element is, hydrogen has received a lot of acknowledgement throughout history.
good emitter of heat radiation so a lot of heat will be lost to the
In this recent century, there is ease into taking our technology as something for granted. After all, technology has opened up our abilities to instantly connect to the other side of the world, instantly retrieve information from the Internet, and instantly listen to digital content if desired. However, while a cell phone, laptop, and iPod has many differences from one another, all of those three devices share one item in common at the very least and that is a Lithium-Ion Battery.
The oxygen atom is joined to the hydrogen atom as well as the carbon atom, which makes the oxygen a part of a hydroxyl group. These atoms are generally part of a hydrocarbon chain. These alcohols can take away water from the body, in which a hydrocarbon chain has replaced a hydrogen atom. Alcohols have a general structure of CnH2n+1OH. The aim of this investigation is to see the link between the number of carbon atoms in a fuel with the amount of energy it releases.
Hydrocarbons are compounds formed by carbon and hydrogen atoms. They are used as fuels to produce energy in incomplete and complete combustion reactions. Incomplete combustion occurs when hydrocarbons react with a small amount of oxygen (O2), whilst complete combustion occurs when hydrocarbons react with large amounts of oxygen. Incomplete combustions produce water (H2O), carbon monoxide (CO) and/or soot (C). The CO and soot produced from incomplete combustion can have harmful consequences on humans and the environment. They not only damage human health, but also contribute to the current issue of global warming, ozone formation, and black carbon footprint. That being said, CO is vital to the human body in order to properly function.
Hart, David. " Hydrogen: A Truly Sustainable Transport Fuel?" Frontiers in Ecology and the Environment 1.3 (2003): 138-45. Web. Kühne, Reinhart. "
The three fossil fuels- coal, crude oil, and gas slowly formed over millions of years. These days, we use fossil fuels to power everything- homes, buildings, cars, computers, lights, etc. However, fossil fuels deposits will run out soon, which is a huge problem. Extracting, transporting, and burning fossil fuels are dangerous. There are also many negative biological and environmental impacts that result from the use of fossil fuels, such as ocean acidification, groundwater contamination, land subsidence, oil spills, and global warming. Therefore, we should be trying to reduce our dependence on fossil fuels and explore alternative energy sources such as wind energy, hydroelectricity, and solar energy instead. Our world depends on fossil fuels, but they can also hurt us. Fossil fuels are both a blessing and a curse.
Recent years have shown an increasingly large need for a practical renewable energy source for such reasons as diminishing fossil fuels and increases in greenhouse gasses. Hydrogen appears to be a way out of this gasoline-dug hole, or at least, a way out in the future. Hydrogen fuel cell cars are being engineered as we speak as the technologies to refuel them cleanly are being proposed. Unfortunately, most of the technologies associated with hydrogen are still in the prototype/pre-production stages and require better enhancements before becoming mainstream. This paper assesses the practicality of hydrogen power in cars both now and in the future while explicating the actual process of how a hydrogen fuel cell works.
Hydrogen would be one of the easiest sources of renewable energy to incorporate into our current energy infrastructure. Since hydrogen is a gas of normal temperature, it is possible to have it be used as a fuel in vehicles similar to current ones. For example, Hydrogen could be introduced into the vehicle as a gas, stored...
For years man has relied on energy in order to be successful in life. The industrial revolution relied on coal for the new inventions brought into the world. Life as has never been the same since then. However since that time, there has been little done to improve on energy efficiency and humans still primarily rely on fossil fuels for energy. For over a hundred years the Earth has become more polluted and dirtier than ever before. Now, with new, innovative technology there is an opportunity to change that and to rely on renewable, cleaner sources of energy. The main source of energy for the world should be alternative energy instead of energy from fossil fuels.