...value 3. Feedwater oxygen content Temperature and ph value influence the aggressiveness of corrosion. The higher the temperature, and the lower the pH value the increased aggressiveness of the feedwater. The dissolved oxygen content of the feedwater is a large factor in determining the amount of corrosion that will take place. The presence of oxygen, and other non-condensable gases, in the feedwater is a major cause of corrosion in the feedwater piping, boiler, and condensate handling equipment. Deaerator Principles Deaeration is the mechanical removal of dissolved gases from the boiler feedwater. There are three principles that must be met in the design of any deaerator. 1. The incoming feedwater must be heated to the full saturation temperature, corresponding to the steam pressure maintained inside the deaerator . This will lower the solubility of the dissolved gases to zero. 2. The heated feedwater must be mechanically agitated. This is accomplished in a tray deaerator by first spraying the water in a thin film into a steam atmosphere. Creating a thin film reduces the distance the gas bubble has to travel to be released from the water. Next, the water is cascaded over a bank of slotted trays, further reducing the surface tension of the water. This allows for the removal of any gases not liberated by the initial spraying. 3. Adequate steam supply must be passed through the water, in both the spray section and the tray section to sweep out the gases from ...
Words: 1436 - Pages: 6
...vapor) | CO2(carbon dioxide) | CH4(methane) | N2O(nitrous oxide) | | With NO Greenhouse Gases | 0 | 0 | 0 | 0 | -1 | Today | 70% Relative Humidity | 388ppm | 1.843ppm | 0.317ppm | 57 | Ice Age | ? | 180ppm | 0.380ppm | 0.215ppm | 37 | Data Table 2 Concentration of Greenhouse Gases(in ppm) | Number of Clouds | Equilibrium Atmospheric Temperature (in °F) | 0 | 0 | -2 | 0 | 3 | 17 | Data Table 3 Number of Glass Panes | Equilibrium Atmospheric Temperature (in °F) | | | 0 | -2 | 1 | 88 | Data Table 4 Gas Molecule | # of Infrared Photons Absorbed (out of 20) | # of Visible Photons Absorbed (out of 20) | | Trial 1 | Trial 2 | Trial 3 | Average # of Infrared Photons Absorbed | Trial 1 | Trial 2 | Trial 3 | Average # of Visible Photons Absorbed | CH4 (methane) | 11 | 9 | 10 | 10 | 0 | 0 | 0 | 0 | CO2 (carbon dioxide) | 9 | 8 | 9 | 8 | 0 | 0 | 0 | 0 | H2O (water vapor) | 9 | 11 | 6 | 8 | 0 | 0 | 0 | 0 | N2 (nitrogen) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | O2 (oxygen) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | Questions For multiple choice and fill in the blank questions, type the letter of your chosen answer into the space provided below the question. For short answer questions, type your answer in the space provided below the question. Note that there are THREE PAGES OF QUESTIONS below. Each question is worth 4 points. Experiment 1 1. In 2 or 3 sentences in the space below, compare the direction of the paths of sunlight and infrared...
Words: 960 - Pages: 4
...CO2(carbon dioxide) | CH4(methane) | N2O(nitrous oxide) | | With NO Greenhouse Gases | 0 | 0 | 0 | 0 | -1 | Today | 70% Relative Humidity | 388ppm | 1.843ppm | .317ppm | 57 | Ice Age | ? | 180ppm | .380ppm | .215ppm | 37 | Data Table 2 Concentration of Greenhouse Gases(in ppm) | Number of Clouds | Equilibrium Atmospheric Temperature (in °F) | 0 | 0 | -2 | 0 | 3 | 17 | Data Table 3 Number of Glass Panes | Equilibrium Atmospheric Temperature (in °F) | | | 0 | -2 | 1 | 88 | Data Table 4 Gas Molecule | # of Infrared Photons Absorbed (out of 20) | # of Visible Photons Absorbed (out of 20) | | Trial 1 | Trial 2 | Trial 3 | Average # of Infrared Photons Absorbed | Trial 1 | Trial 2 | Trial 3 | Average # of Visible Photons Absorbed | CH4 (methane) | 11 | 9 | 10 | 10 | 0 | 0 | 0 | 0 | CO2 (carbon dioxide) | 9 | 8 | 9 | 8 | 0 | 0 | 0 | 0 | H2O (water vapor) | 9 | 11 | 6 | 8 | 0 | 0 | 0 | 0 | N2 (nitrogen) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | O2 (oxygen) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | Questions For multiple choice and fill in the blank questions, type the letter of your chosen answer into the space provided below the question. For short answer questions, type your answer in the space provided below the question. Note that there are THREE PAGES OF QUESTIONS below. Each multiple choice question is worth 3 points and each short answer question is worth 4 points. Experiment 1 1. In 2 or 3 sentences in the space below, compare the direction of the paths of sunlight...
Words: 913 - Pages: 4
...changes is fundamental to managing these patients effectively (see Chapter 1, Anatomy and Physiology of the Respiratory Tract). NORMAL MECHANISM OF HUMIDIFICATION The upper respiratory system: the nose, pharynx, larynx and the trachea (Fig. 1), normally provides an effective system for conditioning inspired gases. As well as acting as a filter for foreign particles and microbes, the upper airway also warms and humidifies inspired gases so that the gas travelling beyond the carina enters the lower airways and the alveoli at body temperature and fully saturated with water vapour.1 As inspired air enters the upper airway and passes over the nasal turbinates and conchae, gas flow becomes turbulent. This leads to an increase in the number of gas molecules coming into contact with the nasal mucosa. The nasal mucosa is highly vascular and is kept moist by a combination of secretions from mucous glands and direct transudation of fluid through cell walls.1,2 The secreted mucus is hydroscopic and its viscosity varies depending on its glycoprotein content.2,3 The turbulent gas flow results in an increasing efficiency in the warming and conditioning of inspired gases by turbulent convection. As the air is warmed, water from the mucosa evaporates and is transferred to the incoming gas. In normal conditions, when the upper respiratory tract is normal, room air is inhaled at a temperature of around 20C with a relative humidity of 50%. As it passes across the warmer and more...
Words: 4147 - Pages: 17
...INCINERATOR Construction Incinerator is in the shape of a vertical cylindrical chamber with an inverted funnel shaped chimney at the the top. The cylindrical chamber consists of a burning chamber just as in case of oil fired burners, which are lined with refractory materials at the inside. An oil fired burner is provided to initiate the ignition process. It is extremely important that the temperature inside the cylinder is controlled and for this reason thermostats are used. To provide an uninterrupted flow of air for the combustion, forced draft fans are provided. The air supplied is directed upwards in swirls with the help of strategically designed ports. A rotating shaft with blades is attached at the center, which helps for a faster combustion process and also prevents incomplete combustion. The ash and the residue thus generated due to the combustion is forced at the periphery by this rotating shaft. The ash is pushed into an ash hopper and it gets collected there. A door is provided to dump the waste inside the incinerator. This door pneumatically operated and when opened shuts down the fan and the burner automatically. Not all the ash gets collected in the ash hopper. Some of the ash due to the forced air goes up to the chimney with the smoke. To remove this ash from the smoke a char eliminator is used. A char eliminator is similar to a filter paper. A sight glass is provided at the side of the incinerator to keep a watch at the burning process. All the processes...
Words: 2478 - Pages: 10
...of parallel flow of material and combustion gases in the burning zone and the regenerative preheating of combustion air, is described in detail in „pfr1.pdf“. Fig. 2: Two Circular MAERZ® Kilns Type R2 (400 tpd) Fig. 1: Gas Flow in the Circular MAERZ® Kiln For larger capacities, e.g. from 300 to 800 tons per day, kilns of circular cross section are recommended. These kilns have circular ring channels collecting the combustion gases before they enter the nonburning shaft via the crossover channel, as illustrated in Fig. 1. The gases exit the burning shaft and enter the non-burning shaft radially around the complete shaft perimeter thereby guaranteeing an absolute even heat distribution. This is a major key factor in ensuring the high quality of the burned lime or dolomite. The charging system has to ensure perfectly symmetrical charging of the shafts. A bucket positioned vertically above each shaft is used for charging raw stone into the kiln shafts. Stone distribution is further improved by rotating the bucket during charging from the conveyor belts or vibrating feeders. As described above, the circular shaft design facilitates uniform stone and fuel distribution during charging and calcination throughout the complete shaft cross section. As a result this kiln type produces the best product quality of all PFR-Kiln types. In addition to the classic design of the refractory kiln lining, as shown in Fig. 2 and 3, an air cooled “suspended inner cylinder”...
Words: 362 - Pages: 2
...Name of the Experiment: Avogadro’s Law Type Your Name: Date: 11/17/13 Experiment 1 ________________________________________ 1. For each gas, record the following: Propane Butane Methane a Name and formula C3H8 C4H10 CH4 b Mass of 100 mL gas (g) 0.274g 0.361g 0.100g c Molecular weight of the gas (g/mole) 44.10g/mol 58.12g/mol 16.04g/mol d Number of moles in the 100 mL sample 0.0062mol 0.0062mol 0.0062mol Average of all 3 gases: (0.0062+0.0062+0.0062) / 3 = 0.0062 2. To verify Avogadro's Law, calculate the average number of moles for the three gases along with the percent deviation for each gas, according to the formula: % deviation = |(moles of gas) - (average for all gases)| / (average for all gases) * 100% %deviation= (0.0062 -0.0062) mol / 0.0062mol *100% % deviation= 0% a Average number of moles in 100 mL for all three gases 0.0062moles b % deviation for each gas All 3 the same: 0% c Do your results confirm Avogadro's Law? Yes 4. Based on the calculated number of moles in one 1 atm of gas, how many molecules are in 1 atm of gas? (There are 6.022 x 1023 molecules/mole) Since all 3 gases have the same number of moles I will calculate 1 formula for all 3. 0.0062mol (6.022 x 1023 molecules/mol)= 0.0373364 →3.73 x 1022 molecules for each gas are in 1atm. 5. Even though the number of molecules in 1 atm of gas at constant pressure and temperature is identical, the number of atoms in the...
Words: 467 - Pages: 2
...CHM 1101 Introductory Chemistry Dawn Fox Medeba Uzzi August, 2007 Compiled and edited by Medeba Uzzi Authors’ Note This document is an initiative by the authors in an attempt to deal with what they think may be one of the reasons contributing to the relatively high failure rate in the introductory Chemistry course (CHM 1101) at the University of Guyana. It was brought to our attention that many first year students taking CHM 1101 are unable to efficiently cope with the frenetic pace of the Semester system and even less able to deal comprehensively with the large content in CHM 1101. It is hoped that by providing this paper, students will not need to make lots of notes in lectures and so they can focus on grasping the concepts taught. The document is meant to be a guide to the topics covered in CHM 1101 and is by no means exhaustive. Students are still required to attend classes regularly and punctually and to engage meaningfully in lectures and tutorials. Further, supplemental reading of these topics in any good General Chemistry text is expected. Dawn Fox Medeba Uzzi 2 SECTION 1 – Modules A – D: section deals with the foundation for chemistry. It introduces students to matter & its classification, Atom & its structure, Periodic table and chemical rxns. Introduction to Science and Measurement What is Chemistry? – Chemistry is the study of matter and its transformations Natural sciences refer to the systematic study of the natural world (our...
Words: 13953 - Pages: 56
...opinion of Woodridge and Morgan, the implication of the term vulcanicity is very wide. It covers all those processes in which molten rock material or magma rises into the crust or is poured out on its surface, there to solidify as a crystalline or semi-crystalline rock. In either case, this activity (vulcanicity) may have a profound effect on surface features. It may be pointed out that there are two forms of vulcanicity: intrusive and extrusive. A volcano, on the other hand, is the resultant effect of the process of vulcanicity. A. Holmes has defined a volcano as under: "A volcano is essentially a fissure or vent, communicating with the interior, from which flows of lava, fountains of incandescent (red-hot) spray, or explosive bursts of gases and volcanic ashes are erupted at the surface". In other words, any opening in the crust of the earth that allows molten rock-forming materials to reach the surface is properly called a volcano. The deposits of Lava surrounding the vent area also considered to be part of the volcano. It may be noted that lavas are poured onto the surface along both the divergent and convergent plate...
Words: 1249 - Pages: 5
...major threat of today’s world is global warming. Due to various reasons global warming turns out to be a serious issue in the last few years. Today people believe in global warming while this concept was not so much believed and people interpreted in some other meanings what was happening in the past. Global warming is amplification in the temperature of earth because of industrial pollution, fossil fuels, and agricultural practices caused by human being, other and natural gas emissions. Because of this greenhouse gases are released in large quantity. Solar radiations of short wave type go down under the earth and increase its surface temperature, while infrared radiations of long wave type that is released by earth are absorbed and then gases re-emit these waves again. And this climax of greenhouse gases is the cause of change in our earth atmosphere. Serious problems can arise when large quantity of these greenhouse gases buildup in our atmosphere because these gases improved the heat trapping ability of earth. Major Causes of Global Warming The causes of global warming are divided into two categories mentioned in the following: 1. Natural Causes: The causes created by nature are natural causes. One natural cause is an emission of methane gas from wetlands and frosty tundra. Methane gas is called a greenhouse gas that traps heat in the atmosphere of earth. The earth cycle of atmosphere changer is another natural cause. And this atmosphere cycle approximately lasts for 40...
Words: 1245 - Pages: 5
...which absorbs more sunlight and results in warmer temperature. 2. The three examples of greenhouse gasses are Carbon Dioxide, Methane and Nitrous Oxide. 3. Global Warming refers to increase in average temperatures. Greenhouse gasses have an effect on global warming. Gas such as Carbon dioxide leads to climate change over the years. Greenhouse effect can be split into two different categories. First would be the natural Greenhouse effect. This man made greenhouse works by trapping gasses which produces heat by holding it in a huge glass house. The second type of greenhouse effect id the natural greenhouse effect. Some of the activities of man also produce greenhouse gases. These gases keep increasing in the atmosphere. The balance of the greenhouse gases changes and this has effects on the whole of the planet. Burning fossil fuels such as coal, oil and natural gas releases carbon dioxide into the atmosphere. Cutting down and burning trees also produces a lot of carbon dioxide. A group of greenhouse gases called the chlorofluorocarbons (CFC) been used in aerosols, such as hairspray cans, fridges and in making foam plastics. They are found in small amounts in the atmosphere. They are dangerous greenhouse gases because small amounts can trap large amounts of heat. Because there are more and more greenhouse gases in the atmosphere, more heat is trapped which makes the Earth warmer. This is known as Global Warming. 4. The answer is no we cannot live without greenhouse...
Words: 593 - Pages: 3
...increasingly coming home with pitiful catches. Of a number of factors which have led to this situation, one stands out: over-fishing in many areas. According to the Asian Development Bank (ADB), there has been a drop of 90% in the quantity of marine organisms that can be trawled in some traditional fishing areas of the Philippines. This isn’t just a question of declining fish stocks and biodiversity, but also of social impacts and economic losses. Mismanagement of fisheries resources is estimated to cost US$ 420 million annually in lost revenues. At the root of the overfishing problem is weak fisheries management, ineffective policies and poor enforcement of fishery laws. Deforestation After decades of deforestation, which has left about 3% of the original cover, forests continue to be under threat from agriculture and urbanization, illegal logging and forest fires. Sustained forest loss in the Philippines is causing severe soil erosion, and is threatening the country’s rich biodiversity. This is particularly worrying as many of the Philippines’ species, which depend on these forests, are endemic (they cannot be found anywhere else in the world). For example, of 180 native terrestrial mammal species here, about 61% are endemic. Inconsistent laws, inadequate regulations, weak enforcement and lack of funding are making forest conservation a major challenge. Sources • BirdLife. Red Data Book - Threatened Birds of Asia. Accessed July 11th, 2007. • World Bank. Philippines Environment...
Words: 599 - Pages: 3
...Greenhouse Gas Greenhouse gases (GHGs) occur naturally in the Earth’s atmosphere and help to keep the planet hospitable to life by trapping some of the sun’s natural heat. Without this “greenhouse effect,” the Earth’s average surface temperature would be about 33 degrees Celsius cooler than it is currently.4 The most important naturally occurring GHGs associated with this phenomenon are water vapor (H2O), carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O).Other greenhouse gases (e.g., fluorinated gases) are created and emitted solely through human activities. The principal greenhouse gases that enter the atmosphere because of human activities are: * Carbon Dioxide (CO2): Carbon dioxide enters the atmosphere through the burning of fossil fuels (oil, natural gas, and coal), solid waste, trees and wood products, and also as a result of other chemical reactions (e.g., manufacture of cement). Carbon dioxide is also removed from the atmosphere (or “sequestered”) when it is absorbed by plants as part of the biological carbon cycle. * Methane (CH4): Methane is emitted during the production and transport of coal, natural gas, and oil. Methane emissions also result from livestock and other agricultural practices and by the decay of organic waste in municipal solid waste landfills. * Nitrous Oxide (N2O): Nitrous oxide is emitted during agricultural and industrial activities, as well as during combustion of fossil fuels and solid waste. * Fluorinated Gases: Hydrofluorocarbons...
Words: 2486 - Pages: 10
...The term ‘carbon footprint’ has become tremendously popular over the last few years and is now in widespread use across the media. With climate change high up on the political and corporate agenda, carbon footprint calculations are in strong demand. Numerous approaches have been proposed to provide estimates, ranging from basic online calculators to sophisticated life-cycle analysis or input-output-based methods and tools. Despite its ubiquitous use however, there is an apparent lack of academic definitions of what exactly a ‘carbon footprint’ is meant to be. The scientific literature is surprisingly void of clarifications, despite the fact that countless studies in energy and ecological economics that could have claimed to measure a ‘carbon footprint’ have been published over decades. This report explores the apparent discrepancy between public and academic use of the term ‘carbon footprint’ and suggests a scientific definition based on commonly accepted accounting principles and modelling approaches. It addresses methodological question such as system boundaries, completeness, comprehensiveness, units and robustness of the indicator. >>> Processes causing greenhouse gas (GHG) emissions benefit humans by providing consumer goods and services. This benefit, and hence the responsibility for emissions, varies by purpose or consumption category and is unevenly distributed across and within countries. We quantify greenhouse gas emissions associated with the final consumption...
Words: 2231 - Pages: 9
...Operating principles of reciprocating and turbine engines Robert Zimmerman Embry Riddle Operating principles of reciprocating and turbine engines. Many airplanes are equipped with reciprocating engines. This is due to their reciprocating or back and forth movement of the pistons. Two kinds of these motors are. 1. by cylinder arrangement with respect to the crankshaft—radial, in-line, v-type or opposed, or 2. By the method of cooling—liquid or air-cooled. The main advantage of a radial engine is the favorable power-to-weight ratio. V-type engines usually have more horsepower than in-line engines. The horizontally-opposed engine is the most popular engine on smaller aircraft. Opposed engines always have a even number of cylinders. Most are air cooled and have a high power-to-weight ratio due to a light crankcase. The main parts of a reciprocating engine include the cylinders, crankcase, and accessory housing. The intake/exhaust valves, spark plugs, and pistons are located in the cylinders. The crankshaft and connecting rods are located in the crankcase. The magnetos are normally located on the engine accessory housing. Operating Principles Federal Aviation Administration. (2013, July 1) found the basic principle for reciprocating engines involves the conversion of chemical energy, in the form of fuel, into mechanical energy. This occurs within the cylinders of the engine through a process known as the four-stroke operating cycle. These strokes...
Words: 1065 - Pages: 5
