French Education System Essays - DraftBedroom,

French Education System D'abord, les ?tudes, en France, sont s?rieux ! Aux Etats-Unis on peut terminer le lyc?e sans passer un examen (mais ?a va changer tout de suite avec les nouvelle loi de Grey Davis notre `gouverner d'Etat de Califorie). En France les lyc?ens doivent passer le bac, c'est ? dire, le baccalaurate. C'est un examen tr?s important qui marque la fin des ?tudes secondaires et qui determine, en grande partie, l'avenir des lyc?ens. S'ils sont re?us, ils peuvent aller ? l'universit? et continuer leurs ?tudes. S'ils ratent le bac, ils peuvent redoubler et se repr?senter l'ann?e suivante, ou bien ils peuvent faire des ?tudes techniques, ou entrer dans la vie professionelle, ou, pour les gar?ons, faire leur service militaire. Il y a plusiers types de bac. Ils sont d?sign?s par des lettres. Dans chaque s?rie, l'?l?ve doit choisir une sp?cialit?. Il y trois s?ries principales avec leurs sp?cialit?s. Il y le S?rie litt?raire, le Bac L avec langues vivantes, lettres classiques, art et math?matiques. Le S?rie ?conomique et sociale, Bac ES avec les sp?cialit?s de sciences ?conomiques et sociale, math?matiques, et langues vivantes. Et finalment, il y a le S?rie scientifique, le bac S avec math?matiques, physique chimie, sciences de la vie et de la terre, et technologie industrielle. Ces sp?cialit?s sont important parce qu'elles d?terminent le genre d'?tudes universitaires qu'on peut faire, et, par cons?quent, sa profession future. Par exemple, si on veut ?tre m?decin ou pharmacien, il est conseill? de faire un bac S. sp?cialit? sciences de la vie et de la terre. Si on pense faire des ?tudes de droit, et devenir avocat, il est pr?f?rable de faire un bac ES, sp?cialit? sciences ?conomiques et sociales. Normalement, les ?tudes universitaires aux Etas-Unis durent quatre ans, mais en France ils durent au moins trois ans. Aussi, certains jeunes qui ont le bac pr?f?rent ?tudier en I.U.T. (institut Superieur de Technologie) o? ils peuvent obtenir un dipl?me universitaire de technologie apr?s deux ann?es d'?tudes. Les grandes ?coles sont une autre option. Ce sont des ?coles sp?cialis?es dans certains domaines : commerce, administration publique, profesions d'ing?nieur, etc. Pour entrer dans ces ?cole prestigieuses, il faut passer un concours extr?mement difficile, auquel la plupart des candidats ?chouent. Cependant, si on est re?u, et si on obtient le dipl?me d'une de ces ?coles, on a toutes les chances de faire une brillante carri?re dans le commerce, la finance, l'industrie et m?me la politique. Comme on peut le voir, les dipl?mes ont beaucoup d'importance en France. Un dipl?me repr?sente une carte d'entr?e dans la vie professionelle. En France, les ?tudes sont s?rieux

Many Uses of the Word ;Con in Spanish

Many Uses of the Word ;Con in Spanish The Spanish word  con,  pronounced much like the English word cone, not like con, is one of the most commonly used prepositions. In most uses, it is the equivalent of the English word with.   The word  con is more versatile than the English with, however, and it may be used in places where with might not be used in English.  For example, con can be paired with certain verbs, can be used to form phrases that function like adverbs, indicate conditions, and form contractions. Con Used With Certain Verbs Con  can be used with various verbs where a different preposition  or none at all would be used in English. Such usages are unpredictable and need to be learned along with the verbs. Spanish Sentence English Translation Verb Combination Es necesario acabar con el escndalo. It is necessary to put an end to the scandal. acabar con/put an end to Para comer, basta con cinco dà ³lares. In order to eat, five dollars is enough. basta con/is enough El coche chocà ³ con el tren. The car crashed into the train. chocà ³ con/crashed into Puedo contar con mis amigos. I can count on my friends. contar con/count on Tengo que enfrentarme con el problema. I have to face up to the problem. enfrentarme con/face up to Me espanto con las hormigas. I am frightened of ants. Me espanto con/to be frightened of Muchas veces sueà ±o con la guerra. I often dream about the war. sueà ±o con/dream about Quiero encontrarme con mi madre. I want to run into my mother. encontrarme con/to run into When used with the verbs above, con could be understood to mean with, but it would be awkward to translate it literally that way. Con Used to Form Phrases That Function Like Adverbs In English, with can be used to form adverbial phrases, but but such phrases using con are far more common in Spanish. In some cases, such adverbial phrases  are used in preference to or instead of synonymous adverbs. This list below is far from complete. Spanish Sentence English Translation Adverbial Phrase/Literal Meaning Habla con intensidad. He speaks intensely. con intensidad/with intensity Me preguntà ³ con cortesà ­a. He asked me courteously. con cortesà ­a/with courtesy Vive con felicidad. She lives happily. con felicidad/with happiness Anda con prisa. She walks fast. con prisa/with speed No reacciona con miedo. She doesn't react fearfully. con miedo/with fear Nos abrazamos con carià ±o. We hugged affectionately. con carià ±o/with caring Comenzà ³ las tareas con buena cara. He began his homework optimistically. con buena cara/with a good face Bailan con confianza. They dance confidently. con confianza/with confidence Hablaron con calma. They spoke calmly. con calma/with calm Habla espaà ±ol con fluidez. She speaks Spanish fluently. con fluidez/with fluency Se viste con humildad. He dresses humbly. con humildad/with humility Da su opinià ³n con libertad. She freely gives her opinion. con libertad/with freedom Te quiero con locura. I love you madly. con locura/with craziness Estamos esperando con ilusià ³n. We are waiting hopefully. con ilusià ³n/with hope Juega fà ºtbol con ganas. He plays soccer enthusiastically. con ganas/with gusto El perro duerme con frecuencia. The dog sleeps often. con frecuencia/with frequency Con Used to Indicate a Condition Sometimes when followed by an infinitive or a noun, con can have a variety of translations to indicate a condition being met or not. Translations for con in this case can include if, despite, and by. Spanish Sentence English Translation Meaning of Condition Con decirle que no tengo dinero, todo estar bien. By telling him that I don't have money, everything will be fine. con decirle/by telling him Con todo, no est enferma. Despite everything, she's not sick. con todo/despite everything Con correr puedes verla. If you run you can see her. con correr/if you run Con Used as a Contraction When con is followed by the pronoun mà ­ or ti to say with me or with you, the phrase is changed to conmigo or contigo, respectively. Spanish Sentence English Translation Contraction Ven conmigo. Come with me. conmigo/with me Vendrà © contigo. I will come with you. contigo/with you Key Takeaways Although con is the usual  equivalent of the English preposition with, it is often used in situations were with is not.Con is frequently paired with numerous verbs in unpredictable ways.Con is also frequently used with prepositional objects to form phrases that function as adverbs in situations where English would more likely simply use an adverb.

Human Resource Essay Example | Topics and Well Written Essays - 1000 words

Human Resource - Essay Example Social needs are the next level of need in the hierarchy. After the satisfaction of the physiological needs and the safety needs the next need is the need for meaningful relationships and to be accepted in the society. An organization’s internal work environment decides the importance of this need. When an organization has a participatory leadership style, the workers start to feel part of the organization and this helps to increase their motivation by satisfying their social needs. An organization can be used this need to increase the motivation of its workers. The management can form teams/ clubs within the organization to recognize good performers. Achievements on the job can be rewarded to increase the commitment of the employees towards their jobs. Esteem needs which follow the social needs are concerned with self-respect, feeling of personal worth, feeling of being unique and recognizable. This need can be used positively by recognition and appreciation of the workers. T he ultimate need in the hierarchy is the self-actualization needs which helps to achieve one’s full potential. This is related to the development of intrinsic capabilities which lead people to seek situations that can utilize their potential. These set of needs can be satisfied by creating opportunities for the workers who can steer ahead themselves. The levels of hierarchy in an organization should be minimized and the personnel can be empowered to plan and execute their tasks which can motivate them to achieve their full potential.

Social Psychology - Prejudice Essay Example | Topics and Well Written Essays - 1000 words

Social Psychology - Prejudice - Essay Example Finally, this paper shall also suggest ways in order to remedy this issue or situation. Social psychologists have attempted to explain prejudice by using various theories. One of the main theories they have used is the theory of innate tendency. This theory basically explains that people are borne with the innate quality of gravitating or liking people who are like them and of disliking or hating other people who are not like him (Sharma & Sharma, 1997). Through the theory of self-love, social psychologists explain how people tend to love themselves. Therefore people are often disgusted by other people who are different from them (Sharma & Sharma, 1997). Social psychologists also point out that the ethnocentric theory is all about the belief that one’s group is moral, right, and rational – and that other cultures are inferior (Sociology Index, 2009). In judging other cultures or beliefs, these individuals tend to base their judgments on their standards – without attempting to understand the perspectives of their members. In yet another theory, the psycho-analytic theory â€Å"considers human experience to be root cause of prejudice† (Sharma & Sharma, 1997. The experiences which reflect favorable outcomes affect the person’s behavior in relation to similar future experiences. Unfavorable experiences also manifest and affect the overall behavior of a person in relation to similar future experiences (Sharma & Sharma, 1997). Prejudices in interracial experiences in Singapore affect the occurrence and prevalence of interracial marriages. This interracial prejudice has affected them to a point where marriages between ethnic lines has not happened often (Country Data, 1989). From 1954 to 1984, rates of marriages between ethnic divides occurred at 5 to 6 percent of all marriages (Country Data, 1989). In considering the innate tendency theory, the

Design Of A Sulfuric Acid Production Plant Engineering Essay

Design Of A Sulfuric Acid Production Plant Engineering Essay This project is prepared according to the requirements of chemical engineering department, and its also a preliminary study of sulfuric acid production plant. The project begins with chapter one which includes introduction, definition of sulfuric acid and shows the main uses of sulfuric acid which have made it an important chemical in the world, followed by chapter two which talks about literature, market survey and the history and current processes for production the sulfuric acid also it gives small glimpse of the prices trends of the raw material and product. That is followed by description for various processes to produce sulfuric acid in chapter three, which ends with the selection of the best process which is the double contact process; the description and flow sheet of the selected process are discussed in chapter four. Material and energy balance results are listed in chapter five and the location of the plant is selected in chapter six by comparing different locations, and the best location for the plant (as its set in this report) is Aqaba city. . Finally, material and energy balance details are discussed in the appendix, that includes the used charts and references. CHAPTER ONE INTRODUCTION 1.1 Definition Sulfuric acid is a strong mineral acid with the molecular formula H2SO4. It is a clear, colorless, odorless, viscous liquid that is very corrosive. It is soluble in water at all concentrations. Sulfuric acid has many applications, and is one of the top products of the chemical industry. There are another names for sulfuric acid, it is sometimes called oil of vitriol.1 Its chemical formula is Figure (1.1.1): Sulfuric Acid Formula1 1.2 Physical and Chemical properties This table shows the main chemical and physical properties of sulfuric acid Sulfuric acid IUPAC Oil of vitriol Other name H2O4S Molecular formula 98.08 g molà ¢Ã‹â€ Ã¢â‚¬â„¢1 Molar mass Clear, colorless, odorless liquid Appearances 1.84 g/cm3, liquid Density 10  Ã‚ °C, 283  K, 50  Ã‚ °F Melting point 337  Ã‚ °C, 610  K, 639  Ã‚ °F Boiling point Miscible Solubility in water à ¢Ã‹â€ Ã¢â‚¬â„¢3 Acidity(pka) pungent odor Odor Non-flammable Flash point 26.7 cP (20  °C) Viscosity 0.3 Ph Table (1.2.1): physical properties1 1.3 Application and Uses Sulfuric acid is a very important chemical commodity, and indeed, a nations sulfuric acid production is a good indicator of its industrial strength. It is used as electrolyte in lead-acid batteries (accumulators) . It is important in the production of fertilizers such as ammonium sulfate (sulfate of ammonia), (NH4)2SO4, and superphosphate, Ca(H2PO4)2, which is formed when rock phosphate is treated with sulfuric acid. It is used to remove oxides from iron and steel before galvanising or electroplating . Concentrated sulfuric acid is used as a dehydrating agent, that is, to remove water, since it has a tendency to form hydrates such as H2SO4.H2O, H2SO4.2H2O. Sulfuric acid is used in the production of nitroglycerine, an inorganic ester organic nitrate, which is used as an explosive. It is used in petroleum refining to wash impurities out of gasoline and other refinery products. It is used in manufacturing of hydrochloric acid, nitric acid, phosphoric acid, ether, plastics, metal sulfates, cellophane, dyes, drugs, perfumes, disinfectants and even glue.1 This chart shows the distribution of using sulfuric acid Figure (1.3.1): Sulfuric Acid Distribution.1 Specification of raw materials sulfur, S, 16 Name, symbol, number 32.065g ·molà ¢Ã‹â€ Ã¢â‚¬â„¢1 Standard atomic weight Yellow colored lumps, crystals, powder, or formed shape Appearances Lumps 75-115 lbs./ft3 Powder 33-80 lbs./ft3 Bulk Density 388.36  K,à ¢Ã¢â€š ¬Ã¢â‚¬Å¡115.21  Ã‚ °C,à ¢Ã¢â€š ¬Ã¢â‚¬Å¡239.38  Ã‚ °F Melting point 717.8  K,à ¢Ã¢â€š ¬Ã¢â‚¬Å¡444.6  Ã‚ °C,à ¢Ã¢â€š ¬Ã¢â‚¬Å¡832.3  Ã‚ °F Boiling point Insoluble Solubility In Water Solid Physical State 1.819 g ·cmà ¢Ã‹â€ Ã¢â‚¬â„¢3 Liquid density at maps. Table (1.3.1): Physical Chemical Properties of Sulfur.1 CHAPTER TWO LITERATURE AND MARKET SURVEY 2.1 History and Current processes The discovery of sulfuric acid is credited to the 8th century chemist and alchemist, Jabir ibn Hayyan (Geber). The acid was later studied by 9th century Persian physician and alchemist Ibn Zakariya al-Razi (Rhazes), who obtained the substance by dry distillation of minerals including iron(II) sulfate heptahydrate, FeSO4 ·7H2O, and copper(II) sulfate pentahydrate, CuSO4 ·5H2O. When heated, these compounds decompose to iron(II) oxide and copper(II) oxide, respectively, giving off water and sulfur trioxide, which combine to produce a dilute solution of sulfuric acid. 1 This method was popularized in Europe through translations of Arabic and Persian treatises, as well as books by European alchemists, such as the 13th-century German Albertus Magnus.1 There are two major processes (lead chamber and contact) for production of sulfuric acid and it is available commercially in a number of grades and concentrations. The lead chamber process, the older of the two processes, is used to produce much of the acid used to make fertilizers; it produces a relatively dilute acid (62%-78% H2SO4). The contact process produces a purer, more concentrated acid but requires purer raw materials and the use of expensive catalysts. n both processes sulfur dioxide is oxidized and dissolved in water. The sulfur dioxide is obtained by burning sulfur, by burning pyrites (iron sulfides), by roasting nonferrous sulfide ores preparatory to smelting, or by burning hydrogen sulfide gas. Some sulfuric acid is also made from ferrous sulfate waste solutions from pickling iron and steel and from waste acid sludge from oil refineries. 1 2.2 Supply and Demand This table shows the production rates of sulfuric acid (in metric tones) in some countries at different years. Production of sulfuric acid in metric tones Year country 1994 1997 2000 2006 France 2227 2242 2269 1755 Germany 3380 3496 4898 4595 Greece 360 675 688 815 Italy 1228 1590 1043 1616 Spain 2348 2810 2418 3500 United kingdom 1225 1205 1058 447 Sweden 518 630 629 1010 Table (2.2.1): Production Rates of Sulfuric Acid.3 This table shows the production and sales amounts of sulfuric acid and the consumption rate of sulfur in Jordan from 2000 to 2005, these amounts in (ton/year). Sulfur consumption (ton/tear) Ù Sulfuric acid Year Sales (ton/year) Production (ton/year) 370925 43824 1108605 2000 309816 46614 919548 2001 351011 43307 1055208 2002 265865 51445 961208 2003 364301 49661 1102899 2004 346345 48323 1046540 2005 Table (2.2.2)Jordan Production, Sales and Raw Material Consumption.5 2.3 Prices trends of the raw material and product The global sulfuric acid market experienced an unprecedented rise and fall in pricing between fall 2007 and spring 2009. Consumption of sulfuric acid for fertilizers fell steeply in the second half of 2008 due to the collapse in the global economy. The second half of 2009 is expected to experience almost flat to slightly positive growth, anticipating the improvement in market conditions in 2010. Trade is expected to fall globally, except for Southeast Asia, which would continue to depend on imports. As of early spring 2009, the market is continuing to deteriorate as the supply shortage situation has been replaced by product oversupply in almost all regions. And the world sulfuric acid supply trends are shown in the following chart. Figure (2.3.1): World Sulfuric Acid Supply.2 CHAPTER THREE PROCESS SELECTION Process Selection Sulfuric acid is an important raw material used in many industrial processes, such as phosphate fertilizer production and to a much lesser extent for nitrogen and potassium fertilizers, sulfuric acid is produced by catalytic oxidation of sulfur dioxide to sulfur trioxide, which is subsequently absorbed in water to form sulfuric acid. There are no major variations of commercial interests on this mentioned chemistry. There are alternatives as to source of Sulfur dioxide and method of conversion to sulfur trioxide. The two most common methods for the conversion of sulfur dioxide to sulfuric acid are: 1. Lead Chamber Process. 2. Contact Process 3.1 Lead Chamber Process This is an old process and was introduced in Europe in near the middle of 18th century, its used to produce much of the acid used to make fertilizers; it produces a- relatively dilute acid (62%-78% H2SO4).The classic lead chamber process consists of three stages: Glover tower, lead chambers and Guy-Lussac Tower. In this method hot sulfuric dioxide gas enters the bottom of the reactor called a Glover tower where it is washed with nitrous vitriol (sulfuric acid with nitric oxide, NO, and nitrogen dioxide, NO2, dissolved in it) and mixed with nitric oxide and nitrogen dioxide gases. The Glover tower serves two functions: concentration of the chamber acid and stripping of nitrogen oxides from the liquid to the gas. Concentration of the chamber acid (62% to 68% H2SO4) is achieved by the hot gases entering the tower which evaporate water from the acid. Some of the sulfur dioxide is oxidized to sulfur trioxide and dissolved in the acid wash to form tower acid or Glover acid (about 78% H2SO4). The dissolved nitrogen oxides are stripped from the acid and carried with the gas out of the Glover tower into the lead chambers. From the acid tower a mixture of gases (including sulfur dioxide and trioxide, nitrogen oxides, nitrogen, oxygen, and steam) is transferred to a lead-lined chamber where it is reacted with more water. Sulfuric acid is formed by a complex series of reactions; it condenses on the walls and collects on the floor of the chamber. There may be from three to twelve chambers in a series. The acid produced in the chambers, often called chamber acid or fertilizer acid, contains 62% to 68% H2SO4. After the gases have passed through the chambers they are passed into a reactor called the Gay-Lussac tower where they are washed with cooled concentrated acid (from the acid tower); the nitrogen oxides and unreacted sulfur dioxide dissolve in the acid to form the nitrous vitriol used in the acid tower. Remaining waste gases are usually discharged into the atmosphere. Product acid at a concentration of 78% H2SO4  is drawn from the cooled acid stream that is circulated from the Glover tower to the Guy-Lussac tower.   Nitrogen losses are made up with nitric acid which is added to the Glover tower. The major disadvantage includes the limitations in throughput, quality and concentration of the acid produced, also the environmental pollution. Figure (3.1.1): Typical process flow sheet for the lead Chamber. 3.2 Contact Process Because of economic reasons Contact plants are widely used compared to the lead plants, they are classified according to the raw materials charged to them: elemental Sulfur burning, spent sulfuric acid and hydrogen sulfide burning, and metal sulfide ores and smelter gas burning. The contributions from these plants to the total acid production are 81, 8, and 11 percent, respectively. The contact process incorporates three basic operations (stages), each of which corresponds to a distinct chemical reaction. First, elemental sulfur is received in a solid form containing various impurities. The sulfur is melted in the sulfur melter in the presence of hydrated lime which neutralizes any acidity present in the sulfur. This neutralization prevents problems of acid corrosion which would otherwise be encountered. Heat for the melting of the sulfur is supplied from steam coils. The molten sulfur is kept agitated to improve heat transfer, to prevent solids settling on the bottom of the sulfur pits and to prevent a crust forming on top. The dirty sulfur is filtered to remove impurities present and after filtering is transferred to the clean sulfur pit where it is kept molten until it is pumped to the burner. Molten sulfur at a temperature of 130 °C is sprayed into the burner in the presence of warm, dry air. The sulfur burns, forming sulfur dioxide S + O2 â‚ ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚   SO2 à ¢Ã‹â€ Ã¢â‚¬  H = -300 kJ mol-1 The resulting sulfur dioxide is fed to a process unit called a converter, where it is catalytically oxidized to sulfur trioxide (SO3): 2SO2 + O2 â‚ ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  2SO3 ΆH = -100 kJ mol-1 Its apparent that the equation gives a decrease in volume; this reaction would be aided by pressure. High conversions are however, obtainable with catalysts at 400 to 500oC with a small excess of oxygen and the use of pressure. The available methods to maximize the formation of SO3: As this is an exothermic process, a decrease in temperature by removal of the heat will favour the formation of SO3. Increased oxygen concentration. SO3 removal (as in the case of the double absorption process). Increased pressure. Catalyst selection, to reduce the working temperature (equilibrium). Longer reaction time. In the contact processes, the sulfur dioxide is converted to sulfur trioxide by the use of metal oxide catalyst, the characteristics of the used catalyst are: Porous carrier having large surface area, controlled pore size and resistance to process gases at high temperature; in pellet form if used in fixed bed and powdered form if used for fluidized bed. Ex- Alumina, silica gel, zeolites. Active catalytic agent: Preparations are generally kept secret for the competitive reasons but they usually consist of adding water soluble compounds to gels or porous substrates and firing at temperature below the sintering point. Promoter: Alkali and/or metallic compounds added in trace amounts to enhance the activity of the catalytic agent. A catalyst, vanadium pentoxide (V2O5) is used to increase the reaction rate because its relatively immune to poisons, also because of its low initial investment and only 5% replacement per year. It is only effective above its melting point of 400  °C. The greatest conversion of SO2 to SO3 is reached by passing the gas over several catalyst beds, cooling the gas between each pass so that the reaction temperature remains between 400 and 500  °C. As can be seen the figure. The disadvantages of using the V2O5 catalyst are that it must use dilute SO2 input (7-10%), as a catalyst it is less active and requires high oxygen or sulfur dioxide to give economic conversions also it requires larger converters and thus higher initial investment. Finally, the sulfur trioxide is absorbed in to very concentrated sulfuric acid (a 98-99 percent solution of H2SO4 in water), This operation takes place in the absorbing tower where the gas travels up through the tower, counter-current to the acid falling from the top of the tower producing a thick fuming liquid called oleum, the oleum is mixed carefully with water to avoid producing fine mist of sulfuric acid that is difficult to condense and could escape to pollute the air, the sulfur trioxide in the oleum reacts with the water as follows: SO3 + H2O â‚ ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  H2SO4 à ¢Ã‹â€ Ã¢â‚¬  H = -200 kJ mol-1 It is clear that the reaction is exothermic and the absorbing sulfuric acid has to be cooled continuously; the heat is available at a relatively low temperature and is not worth recovering. The efficiency of the absorption step is related to : The H2SO4 concentration of the absorbing liquid. (98.5 99.5%). The temperature range of the liquid (normally 70 -120 0C). The technique of the acid distribution. The raw gas humidity (mist passes the absorption equipment). The mist filter. The temperature of incoming gas. The co-current or countercurrent character of the gas stream in the absorbing liquid. Main disadvantages of the contact process are that concentrated acid (98%) of high purity can be produced directly and that compact plants of quite high capacity have now become rather common place. The contact process can be applied in different techniques; three of those techniques are described in the following sections 3.2.1 Single contact / single absorption process After purification and drying, the SO2 is converted to SO3 using a series of four catalyst beds, containing alkali and V2O5. Afterwards, the SO3 is absorbed in concentrated sulfuric acid and, if necessary, an oleum absorber is installed upstream. SO3 reacts with the water contained in the absorber acid to yield H2SO4. The absorber acid is kept at the desired concentration of approximately 99% w/w by addition of water or dilute H2SO4. The single contact/single absorption process is generally used for gases with an SO2 Content from 3 6 %. New single contact plants are built only for inlet gases with substantial fluctuation of the SO2 content. The investment cost of this technique is low compared to the investment cost of double contact plants. Figure (3.2.1.1): Typical process flow sheet for a single catalysis plant. 3.2.2 Double Contact/ Double Absorption Process The double contact process was implemented to develop the single contact/single absorption process. In this process a primary SO2 conversion of 85 95 % is achieved in the first catalysis stage of the converter before entry into an intermediate absorber, depending on the arrangement of the converter beds and the contact time. What makes the double contact/double absorption process more advantageous is that its ability to feed gases with higher SO2 concentrations than would be possible with the single catalysis process. Which leads to smaller gas volumes and therefore smaller equipment with comparable production capacities. This results in a considerably higher conversion rate, if the residual gas is passed through the following converter beds (usually one or two). The SO3 which is formed in the second catalysis stage is absorbed in the final absorber. In general the process uses gases with an SO2 content of 10 t o11 %. The inlet gas temperature is about 4000C. Gases with lower temperatures require reheating from 50 to 4000C. This is usually carried out with recovered heats from the conversion process. Operating the double contact process at an elevated pressure of 5 bar increases the conversion rate by shifting the conversion equilibrium and favouring the formation of SO3. The disadvantages are higher electricity consumption and, at the same time, less steam production. Higher NOx emissions are caused by higher sulfur combustion temperatures (18000C), but savings of 10 -17 % on investment costs are gained. Figure 3.2.2.1: Typical process flow sheet for a sulfur burning double catalysis plant. 3.2.3 Wet catalysis process The wet catalysis process is applicable to wet SO2 gases. The potential for the formation of sulfuric acid mist might require tail gas treatment. Wet SO2 gases (eg. from the burning of H2S gases or from the catalytic conversion of H2S gases) are directly supplied into the contact tower without previous drying. SO3 formed by the catalytic conversion immediately reacts with the moisture of the gases, thereby forming the acetic acid. The sulfuric acid is condensed in a condenser installed after the contact tower. Factors Sulfuric Acid Production By Lead Chamber process Sulfuric Acid Production By single contact/single absorption process Sulfuric Acid Production By double contact/double absorption process Sulfuric Acid Production By Wet Catalysis process Health and safety hazards involved Less safe, waste gases are discharged to the atmosphere Less amount of SO3 is absorbed so the rest is discharged to the atmosphere A larger amount of SO3 is absorbed A larger amount of SO3 is absorbed Operating cost High operating cost Less operating The least operating cost Less operating cost Raw material SO2, NO, NO2, O2, H2O. Melted sulfur, O2, SO2, SO3. Melted sulfur, H2O, O2, SO2, SO3. Wet SO2 gases, H2S, O2, SO3. Waste products and by products Exhaust gases are discharged to the atmosphere Large amounts of SO2 gas are discharged to the atmosphere Less amounts of SO2 gas are discharged to the atmosphere, less heat released after each successive catalyst bed. A larger amount of SO3 is absorbed Equipment Acid Tower (Glover Tower), Lead Chambers, Reactor (Gay-lussac Tower) Air dryer, burner, waste heat boiler, converter, single absorption column. Air dryer, burner, waste heat boiler, converter, intermediate and external absorption column. Burner, convertor, acid tower. Yield Yields 78% H2SO4 New plants achieve 98 to99 % conversion rates Yields about 98% Yields 70 to 80 % H2SO4   Environmental pollution More gases are discharged to the atmosphere More gases discharged to the atmosphere Less gases discharged to the atmosphere More gases are discharger to the atmosphere Purity of products Low purity Low purity High purity Low purity Table (3.2.1): Process selection Factors Sulfuric Acid Production By Lead Chamber process Sulfuric Acid Production By single contact/single absorption process Sulfuric Acid Production By double contact/double absorption process Sulfuric Acid Production By Wet Catalysis process Health and safety hazards involved 5 5 5 3 Operating cost 6 4 7 5 Raw material 6 5 7 5 Waste products and by products 6 6 7 5 Equipment 7 5 8 6 Yield 5 6 7 9 Environmental pollution 5 5 6 4 Purity of products 6 5 7 9 Total (80) 46 41 54 46 Table (3.2.2): Process Selection According to the discussion and the data presented above we choose the Double Contact/Double Absorption process. CHAPTER FOUR PROCESS DISCRIPTION 4.1 Production of H2SO4 by double contact process The process begins in the burner, in which the melt sulfur is pumped to the burner where it is burnt in an excess of dry air. The gas exiting the burner is maintained at (8 9%v/v) sulfur dioxide and approximately 830 °C due to the heat produced by the exothermic reaction. Sulfurs on burning gives about one third of heat combustion of coal ,and this heat raises the temperature of combustion gases roughly in accordance with the figure (4.1.1) as shown. Figure (4.1.1): Theoretical Flame Temperature.8 This heat is high in temperature and there is plenty of it, consequently it is worth utilizing and the hot gases are led across pipes through which the water passes. The water is heated, steam is raised and the gases are cooled. The sulfur dioxide/air gas mixture is then passed through the stream to converter. The sulfur dioxide is converted to sulfur trioxide by reacting with oxygen over a catalyst. This reaction is described by the equation: 2SO2 + O2 â‚ ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  2SO3 ΆH = -100 kJ mol-1 This reaction occurs in the converter, a four-stage reaction vessel with each stage consisting of a solid catalyst bed through which the gas is passed. The catalyst used is vanadium pentoxide (V2O5), and potassium sulphate dispersed on a silica base which forms a porous support, giving a large surface area for reaction. This reaction is exothermic and its equilibrium constant decreases with increasing temperature (Le Chatelier.s Principle). Figure (4.1.2) shows the percentage conversion of SO2 to SO3 that would be reached at an SO2 concentration of 8% v/v and a range of gas temperatures. However, the reaction rate is also temperature dependent, so that if the temperature becomes too low the equilibrium point will not be reached. In practice, the gas temperature must be maintained between (400 500 °C) to maintain a high reaction rate and also high conversion equilibrium. As the reaction is exothermic, heat is generated across each of the catalyst beds. This heat must be removed between each stage to maintain the optimum reaction temperature into the following stage. The temperature rise through each catalyst bed and the inter-stage cooling is shown in Figure (4.1.2). Figure (4.1.2): The Temperature Rise Through Beds.7 The gas after passing through three catalyst bed goes to the first absorption tower where the Sulfur trioxide is removed. The gas is then reheated to about 420 C, passed through the fourth catalyst bed, then cooled and sent to a second absorption tower. The gas mixture goes to the first and second absorption tower, a packed tower where SO3 is absorbed into a counter-current flow of 98 99% sulfuric acid. The overall reaction can be described by the following equation, where sulfur trioxide reacts with the free water to produce sulfuric acid: SO3 + H2O â‚ ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  Ã¢â€š ¬Ã‚  H2SO4 à ¢Ã‹â€ Ã¢â‚¬  H = -200 kJ mol-1 The circulating sulfuric acid must be maintained at about 98% concentration and temperature is controlled in the desired rang of (70 °C_90 °C) to maximize the absorption efficiency. The acid strength is important because the vapor pressure of sulfur trioxide above sulfuric acid is at a minimum at an acid strength of 98% (see Figure (4.1. 3)). At higher concentrations the increased vapor pressure is caused by SO3 and at lower concentrations the water vapor pressure increases sharply and the resultant acid mist is not readily re-absorbed and escapes to the atmosphere. A stream of sulfuric acid is continuously bled off and cooled through a plate heat exchanger before being passed into the storage tanks. Figure (4.1.3): Relation Between Vapor Pressure and Concentration.7 Figure (4.1.4) : Flow Sheet CHAPTER FIVE ENERGY AND MASS BALANCE 5.1 MASS BALANCE *Drier: Components Amount % H20 1.27 1.3 O2 21.12 23 N2 69.4 75.7 Temperature 25C pressure 1 atm M1 M2 Components Amount % H2SO4 39.4 98 H2O 0.8 2 Temperature 150C pressure 1 atm M3 Components Amount % O2 21.12 23.3 N2 69.4 76.7 Temperature 25C pressure 1 atm M4 Components Amount % H2SO4 39.42 95 H2O 2.1 5 Temperature 150C pressure 1 atm *Burner: M3 Components Amount % O2 21.12 23.3 N2 69.4 76.7 Temperature 26C pressure 1 atm M5 Components Amount % S 3.76 100 Components Amount % SO2 28.16 29 O2 7.04 7 N2 69.4 64 Temperature 830C pressure 1 atm   M6 *Converter: M6 Components Amount % SO2 28.16 29 O2 7.04 7 N2 69.4 64 Temperature 400C pressure 1 atm M7 Components Amount % O2 2.11 2 N2 69.44 66 SO2 8.45 8 SO3 24.64 24 Temperature 450 pressure 1 atm M8 Components Amount % SO2 26.72 26 O2 1.69 1.6 N2 69.44 66.4 SO3 26.72 26 Temperature 450 pressure 1 atm M9 Components Amount % SO2 0.314 6 O2 0.0768 1.5 N2 3.47 66.5 SO3 1.36 26 Temperature 450 pressure 1 atm M10 Components Amount % SO2 0.314 6 O2 0.0768 1.5 N2 3.47 66.5 SO3 1.36 26 Temperature 450 pressure 1 atm M11 Components Amount % SO2 6.08 6 O2 1.54 6 N2 65.97 66.5 SO3 25.84 26 Temperature

Freedom Through the Pursuit of Dreams in Their Eyes Were Watching God E

Freedom Through the Pursuit of Dreams in Their Eyes Were Watching God   Ã‚  Ã‚  Ã‚  Ã‚  After the Civil War and the emancipation of the slaves, the ex-slaves could not find enough good work to earn a living. Jim Crow laws were installed to push blacks further away from reaching their dreams. These laws were enforced after Plessy v. Ferguson conviction that blacks and whites could have everything "separate but equal." This included schools, transportation, drinking fountains, bathrooms and more. By 1914 all towns were split down the middle with the blacks on one side and whites on the other (Hoobler 51). The Homestead Act was established in 1866 to help blacks grow in their society. Many bought their own farms or went North and learned to linotype or held other professions such as shoemaking (Hoobler 51). With the movement of blacks to the North came the beginning of the Harlem Renaissance, a black movement in New York in which blacks began to more freely express themselves and their ideas (Rood 38). In illustrating gender roles and the class structu re of a black society, author Zora Neale Hurston portrays the changing black society in her novel Their Eyes Were Watching God through characters that follow their dreams, which helps them take possession of their own lives. The role of women in a black society is a major theme of this novel. Many women help demonstrate Hurston's ideas. Hurston uses Janie's grandmother, Nanny, to show one extreme of women in a black society, the women who follow in the footsteps of their ancestors. Nanny is stuck in the past. She still believes in all the things that used to be, and wants to keep things the way they were, but also desires a better life for her granddaughter than she had. When Nanny catc... ...    Works Cited 1. "Booker Taliafero Washington." Alabama Department Archives & History. asc.edu. World Wide Web. 18 Jan. 1996. Available http://www.asc.edu/archives/famous/b_wash.html. 3. Encarta. Vers. 1997. Computer Software. Encarta, 1997. CD-rom. 4. Hurston, Zora Neale. Their Eyes Were Watching God. 1937. 5. Hoobler, Dorothy and Thomas. The African American Family Album. New York, NY: Oxford University Press, 1995 6. "Jim Crow Laws." FX Bulletin Board Systems. Fxbbs.com. World Wide Web. Available http://www.fxbbs.com/reports/jimcrow.html . 7. Nash, Gary B. American Odyssey. USA: Glencoe Division of Macmilla/McGraw-Hill Publishing Company, 1992 8. Rood, Karen L. American Decades 1920-1929. Detroit, MI: Gale Research Inc., 1996 9. Whiston, Julie. World Wide Web. Available http://www.grin.edu/~gardnerj/thirties/jw.html Freedom Through the Pursuit of Dreams in Their Eyes Were Watching God E Freedom Through the Pursuit of Dreams in Their Eyes Were Watching God   Ã‚  Ã‚  Ã‚  Ã‚  After the Civil War and the emancipation of the slaves, the ex-slaves could not find enough good work to earn a living. Jim Crow laws were installed to push blacks further away from reaching their dreams. These laws were enforced after Plessy v. Ferguson conviction that blacks and whites could have everything "separate but equal." This included schools, transportation, drinking fountains, bathrooms and more. By 1914 all towns were split down the middle with the blacks on one side and whites on the other (Hoobler 51). The Homestead Act was established in 1866 to help blacks grow in their society. Many bought their own farms or went North and learned to linotype or held other professions such as shoemaking (Hoobler 51). With the movement of blacks to the North came the beginning of the Harlem Renaissance, a black movement in New York in which blacks began to more freely express themselves and their ideas (Rood 38). In illustrating gender roles and the class structu re of a black society, author Zora Neale Hurston portrays the changing black society in her novel Their Eyes Were Watching God through characters that follow their dreams, which helps them take possession of their own lives. The role of women in a black society is a major theme of this novel. Many women help demonstrate Hurston's ideas. Hurston uses Janie's grandmother, Nanny, to show one extreme of women in a black society, the women who follow in the footsteps of their ancestors. Nanny is stuck in the past. She still believes in all the things that used to be, and wants to keep things the way they were, but also desires a better life for her granddaughter than she had. When Nanny catc... ...    Works Cited 1. "Booker Taliafero Washington." Alabama Department Archives & History. asc.edu. World Wide Web. 18 Jan. 1996. Available http://www.asc.edu/archives/famous/b_wash.html. 3. Encarta. Vers. 1997. Computer Software. Encarta, 1997. CD-rom. 4. Hurston, Zora Neale. Their Eyes Were Watching God. 1937. 5. Hoobler, Dorothy and Thomas. The African American Family Album. New York, NY: Oxford University Press, 1995 6. "Jim Crow Laws." FX Bulletin Board Systems. Fxbbs.com. World Wide Web. Available http://www.fxbbs.com/reports/jimcrow.html . 7. Nash, Gary B. American Odyssey. USA: Glencoe Division of Macmilla/McGraw-Hill Publishing Company, 1992 8. Rood, Karen L. American Decades 1920-1929. Detroit, MI: Gale Research Inc., 1996 9. Whiston, Julie. World Wide Web. Available http://www.grin.edu/~gardnerj/thirties/jw.html

Code of Ethics of Goldman Sachs’

Title:The effectiveness of Goldman Sachs’ code of ethics Date:17 October 2012 To:CEO, Lloyd C. Blankfein Introduction The code of ethics  is adopted by organizations to assist members in understanding the difference between ‘right' and ‘wrong' and in applying that understanding to their decisions. An effective code of ethics should also help to delineate the proper procedures to determine whether a violation of the code of ethics has occurred and, if so, what remedies should be imposed.After reviewing the company’s code of ethics, we found that it has well established the concept of business ethics and the company’s objective, and also several kinds of encouragement to promote the ethical business behavior effectively. The company’s code of ethics, however, is not practical enough for implementation as the content is too general and vague, and there are not enough guidelines and regulations to help the staff to detect or solve the ethical iss ues. What makes the Code of Ethics Effective: According to the code of ethics, the employees are encouraged to expose any misconducts or unethical issues in the company.The company has also established a certain department, the Global Compliance Division or Legal Department, as the platform for reporting any violation of the code, and it also helps the employees to identify and escalate potential ethical issues. Meanwhile, the company has also set up the Non-Retaliation Policy which strictly prohibits the retaliation against anyone who reports in good faith a possible violation of the Code. Under those policies and procedures, the employees will feel easy to voice out if they found something going in the wrong track.What makes the Code of Ethics Ineffective: The code of ethics of the company consists a large portion of text about the general code of ethics which is applied to every individual unit, but it emphasis less on the code for investment banking industry, such as insider dea ling, money laundering, outside business activities and relationship and other potential conflict of interest, and staff’s personal financial affairs. Without any detailed case illustration for each of the particular issues, employees may feel hard to follow the code.This imposes potential risks for employees to make unethical transactions unknowingly. Moreover, the code does not strictly restrict the actions of personal conflicts of interest but are allowed if approved by the firm that may violate the independence of professional. Audit firm prohibited any conflicts of interest which had been stated clearly on the statement. Auditors, for example, are prohibited to accept any favors which violate the professional. Another weakness of the code is that it omits the implementation and administration policies.There are no content how the company supervises the implementation of the code, what the company do if the code is found to be not effective, how long the company reviews t he code and so on. Also, the code illustrates that the company take a passive role on discovering the ethical issues. The code requires employees take their own initiatives to report any unethical issues. However, it is not guaranteed that all employees are going to follow the code. There is a risk of undisclosed misconduct by employees if the company does not investigate in it. Improvement The code of ethics specifically focuses on banking industry.Take Bank of America’s code as an example. Although it is impossible to define every action that could be reasonably interpreted as a conflict of interest, company also defines several potential conflicts of interest as examples with a brief description so that everyone can have an idea on conflict of interest. In addition, the code has stated employees should conduct their financial affairs responsibly and keep their business expenses in order. The bank is prohibited money laundering and economic sanctions which have also mention ed in the code. Those are helpful to provide a clear picture to staff on what they should conduct.It is good practice to have the way reporting the misconduct issue, but company is still played as passive role. And also it may be biases if the issue is examined by internal staff from other departments. To be independence, establishing Committees involved external individual or professional to monitor and investigate the misconducts and unethical issues, and the committees may directly notify the Board of Director. Company’s code of ethics can be introduced during the orientation. Each new employee may be requested to complete a set of ethical questions after the introduction to ensure everyone understand this code.The failure may be requested to attend another ethical course to recap the important sections. One of global investment bank, Greenhill & Co holds information and training sessions to promote compliance with the laws, rules and regulations that affect their business . Conclusion: It is appreciated that the company put effort on setting the code of ethics. The above suggestions are given to your kindly consideration as it is good for the company to review the code once again in order to maintain high standard of integrity.