The Crude Oil Distillation Engineering Essay

The Crude Oil Distillation Engineering Essay Basically, the product produced in this process can be categoried into 4 group, they are: light distillates, middle distillates, heavy distillates and others. The example of light distillates are liquid petroleum gas (LPG), gasoline, and kerosene. Apart from that, the products that can be classified as middle distillates are residential heating fuel and aautomoblie diesel fuels. Additionally, bunker fuel oils is an example of heavy distillataes, while petroleum cokes, lubricating oils and carban black are the other products in this distillation process. The brief description of crude oil distillation unit (CDU) process is as follow. First of all, the incoming crude oils is heating up before it is entering the fractionation column by heat exchanger. After that, the crude oil will pass through an equipment, called desalter, to remove water droplets and inorganic salts that contained in crude oil. Then, it will be further heating by heat exchanger. Next, crude oil will enter a furnace. At here, it will be heating up to 330-350 Â °C. The crude oil then is flashed in the atmospheric distillation column. At here, it is separated into a number of fraction with a particular boiling range. When each fraction in the distillation column reaches a tray where the temperature is just below its own boiling point, crude oil will be condensed and changes back into liquid phase. Moreover, heaviest fractions will condense on the lower trays and lighter fractions will condense on the higher trays in the column. At different elevations in the column, the fractions actually can be drawn out on gravity through pipes, for further processing in the refinery process by using a special trays called draw-off trays. The fraction is drawn out from the top, side and bottom of the distillation column. These fraction is the products that produced in this distallation process. Vacuum Distillation Unit (VDU) For vacuum distillation unit (VDU), its main purpose is to separate the heavier end products such as vacuum gas oil and slop wax that is from the atmospheric distillation unit. The brief description of the process is as follow. First of all, heavy crude oil is heated by a series of heat exchanger and crude furnace to the desired temperature, which is 350-390 Â °C. After that, the crude oils flashed into the vacuum distillation column to separate the heavy crude oil. The separation is same as the separation in CDU process; light vapors rise to the top and heavier hydrocarbon liquids fall to the bottom. Next, crude steam is injected into the base of the distillation column to enhance the division of lighter boiling components from the bottom liquid. Then, Light vapour gases are abtracted at the top of the distillation column, it is condensed and recycled back to the column as reflux. For light naphtha, it is drawn off and excess gases are sent to flare. However, vacuum gas oil (VGO) and lubricating oils are drawn off and routed for further treatment in hydrotreating units. Apart from that, vacuum residue from the bottom of the distillation column is sent to intermediate storage or typically to be further processed in fluidic catalytic cracking (FCC) process or delayed coking unit. Fluid Catalytic Cracking Fluid catalytic cracking is the primary conversion process in petroleum refinery. It is the unit which utilizes a micro-spherodial catalyst (zeolitic catalyst) which fluidizes when properly aerated. The purpose of this process is to convert high-boiling petroleum fractions (gas oil) to high-value, high-octane gasoline and heating oil. This process uses the instrument called Circulating Fluidized Bed. This Circulating Fluidized Bed has fast fluidization regime and also good for catalyst is the size of less than 0.2 mm. They are also excellent in Gas-solid effective contact, Catalyst effectiveness, Catalyst internal temperature control, and Catalyst regeneration. The operating characteristics of this instrument are; Particle Diameter = 150 mm Geldart Classification = A Temperature = 650 0C Pressure = 100 kPa Superficial gas velocity = 10 m/s Bed depth = 0.85 m Fresh feed flow rate = 300,000 kg/hr Catalyst to oil ratio = 4.8 There are 6 steps of processes that occur in FCC. Reactor, Riser, Cyclones, Stripper, Regenerator, Standpipe and Slide Valve. Firstly, the reactor performance, the feed oil enters the riser near the base and contacts the incoming regenerated catalyst. Then the cracking reactions occur in the vapor phase. The expanded volume of vapors lifts the catalyst and vaporized oil rises. This reaction occurs at a very high speed, usually about few seconds of contact time. Secondly, the riser, which has diameter of 1.2 meters and height of 36.6 meters, has a plug flow with minimum back-mixing. Steam is used to atomize the feed, this increases the availability of the feed. The outlet vapor velocity would reach up to 18 ms -1. The hydrocarbon residence time is 2 seconds. Followed by, Cyclones. It is located at the end of riser to separate the bulk of the catalyst from the vapor. It uses a deflector device to turn catalyst direction downward. It will later undergo two stage cyclones in order to separate the remaining of the catalyst. It then returns the catalyst to the stripper through the diplegs. The product vapors exit the cyclones and flow to the main fractionator column. Then, the spent catalysts fall into the stripper. The valuable hydrocarbons are absorbed within the catalyst bed. Stripping steam, at a rate of 4 kg per 1000 kg of circulating catalyst, is used to strip the hydrocarbons from the catalyst. The catalyst level provides the pressure head which allows the catalyst to flow into the regenerator. The regenerator basically has two functions, one, restores catalyst activity. Two, it supplies heat to crack the feed. Air is the source of oxygen for the combustion of coke. The air blower with 1 m/s (3 ft/s) air velocity to maintain the catalyst bed in a fluidized state. About 14 kPa (2 psi) pressure drops in air distributors to ensure positive air flow through all nozzles. In standpipe and slide valve, it provides the necessary pressure head needed to circulate the catalyst around the unit. The catalyst density in standpipe is 642 kg/m3 (40 lbs/ft3). Slide valve is used to regulate the flow rate of the regenerated catalyst to the riser. Slide valve function is to supply enough catalyst to heat the feed and achieve the desired reactor temperature. Hydrocracking process Crude oil undergoes hydrocracking process after undergoing vacuum distillation and coking processes. Hydrocracking process is a catalytic chemical process used in petroleum refineries for converting the high-boiling constituent hydrocarbons in petroleum crude oils to more valuable lower-boiling products such as gasoline, kerosene, jet fuel and diesel oil. The process takes place in a hydrogen-rich atmosphere at elevated temperatures (260 425 Â °C) and pressures (35 200 bar). This process removes feed contaminants such as nitrogen, sulfur, metals. Hydrogenation occurs in fixed hydrotreating catalyst beds to improve hydrogen/carbon ratios. The size of the molecules must decrease and the atomic H/C ratio must increase if the products are to become useable as conventional fuel products. This is followed by one or more reactors with fixed hydrocracking catalyst beds to dealkylate aromatic rings, open naphthene rings, and hydrocrack paraffin chains. Major products from hydrocracking are jet fuel and diesel, while also high octane rating gasoline fractions is produced. All these products have a very low content of sulfur and other contaminants. Hydrocracking is normally facilitated by a bifunctional catalyst that is capable of rearranging and breaking hydrocarbon chains as well as adding hydrogen to aromatics and olefins to produce naphthenes and alkanes. This process cracks the high-boiling, high molecular weight hydrocarbons into lower-boiling, lower molecular weight olefinic and aromatic hydrocarbons and then hydrogenates them. Any sulfur and nitrogen present in the hydrocracking feedstock are, to a large extent, also hydrogenated and form gaseous hydrogen sulfide (H2S) and ammonia (NH3) which are subsequently removed. The result is that the hydrocracking products are essentially free of sulfur and nitrogen impurities and consist mostly of paraffinic hydrocarbons. Basically, hydrocracking process consist of the splitting or breaking of straight or cyclic hydroca rbons and hydrogenation of the broken bonds. Example: For futher details about the yield and disposition, refer to the table below: Product Yield, volume% feed Disposition Light ends Varies depending upon objectives LPG Naphtha Gasoline, catalytic reformer Diesel Diesel Total volume yield 130 140 Gas oil conversion 60 99% They are two stages of hydrocracking unit; Single Stage Process and Multi Stage Hydrocracker. It is called a single stage process when the treating step is combined with the cracking reaction to occur in one reactor. The catalyst used in a single-stage process comprises a hydrogenation function in combination with a strong cracking function. In the case of high/full conversion is required, it becomes necessary to switch to a multi-stage process, in which the cracking reaction mainly takes place in an added reactor. Two versions of the multi stage hydrocracker have been developed; two stage hydrocracker and series flow hydrocracker. Both two stage and series flow hydrocracking are flexible process. The two stage process is more selective because product made in the first reactor is removed from the second reactor feed. In series flow operation, this product is partly overcracked into lighter products in the second reactor. Schematic of a two-stages hydrocraking unit HYDROTREATING PROCESS (Prepared by DING TIONG SOON, 10UEB01031) Hydrotreating technology is used in refinery processes to remove contaminants such as sulfur, nitrogen, condensed ring aromatics, or metals to produce a clean product for further processing. Hydrotreating process includes Naphtha Hydrotreating, Gasoline Hydrotreating, Mid-Distillate Hydrotreating and FCC Feed Pretreating. The feeds used in this process range from vacuum resid to naphtha , and the products are used as environmentally acceptable clean fuels. In the hydrotreating process oil fractions are reacted with hydrogen in the presence of a catalyst to produce high-value clean products. The operating conditions will depend on the final application. The heart of hydrotreating process is the reactor section, which features a high-pressure reactor vessel and proprietary catalyst and reactor internals technology. Hydrotreating process began when the liquid feed stream is joined by a stream of hydrogen-rich recycle gas. The mixture is then preheated by flowing through a heat exchanger. After that, it is heated to the desired hydrotreating temperature using a fired heater where the feed mixture is totally vaporized. Hydrotreating takes place when the feed mixture flows through a fixed-bed reactor in the presence of a catalyst consisting of an alumina base impregnated with cobalt and molybdenum.The hot reaction products are cooled by flowing through a water-cooled heat exchanger before it flows through the pressure controller (PC) and undergoes a pressure reduction down to about 3 to 5 atmospheres. The resulting mixture of liquid and gas enters the high pressure separator which separates the liquid hydrocarbon from the hydrogen , hydrogen sulfide or ammonia gas. Most of the hydrogen-rich gas from the gas separator vessel is recycled by routing through an amine contractor for the removal of acid gas and is reuse in the reactor section. Any excess gas from the gas separator vessel joins sour gas from the stripping of the reaction product liquid. The liquid from the gas separator vessel is routed through a reboiled or steamed stripper distillation tower. The stripper only have two products ,a top and a bottom. With a steam stripper, downstream processing, typically a salt dryer which is preceded by a vacuum dryer, is required to remove water from treated products. If multiple products are produced, then a fractionator with a fired reboiler is also used. Further separation of LPG gases occurs in the low pressure separator prior to sending the hydrocarbon liquids to fractionation. Meanwhile, the sour gas is sent to the refinerys central gas processing plant for removal of the hydrogen sulfide in the refinerys main amine gas treating unit and through a series of distillation towers. The Importance of hydrotreating is that it helps to improve air quality by desulfurization of fuel oils. Hydrotreating prepares valueable hydrocarbon products from heavy carbon streams and the production of low-sulfer-level fuel oil from residual stocks after distillation of crude oil. Coking (prepared by Soo Voo Yee, 10UEB01889) Coking is a thermal process for the conversion of low value residue to valuable products and coker gas oil. There have two types of coking process, which are delayed coking and fluid coking. For the delayed coking process, at first, the residual oil from the vacuum distillation unit is pumped into the bottom of the main fractionators. Along the way it is pumped to the furnace, some steams are injected to heat it to its thermal cracking temperature of about 4800C. The injected steam helps to minimize the deposition of coke within the furnace tubes. Besides that velocity inside the tube of the furnace is very fast. This is to reduce the loss of heat as a waste of source. Because of the short period in the furnace, so the coking of the feed is delayed until it reaches the large coking drum. Compared to the furnace, drum provides a longer period for the cracking process to proceed to completion. For the gas oil and the lighter components will leave from the top of the drum, left behind the components of liquids and solids. The gasses will be directed to the main fractionators to separate it into gases, naphtha and light and heavy gas oils based on each boiling points.The solid coke is deposited and remains in the coke drum in a porous structure that allows flow through the pores. 16 to 24 hours are needed to fill the drum full as a complete coke drum cycle. The hot mixture is switched to another empty drum, when the first drum is full of the solidified coke. While the second drum is filling, the full drum is steamed out to reduce the hydrocarbon content of the petroleum coke, and then is cooled down with water. The top and bottom heads of the full coke drum are removed, and the solid petroleum coke is removed from the coke drum via hydro jetting. The pressure of the water is about 1250psig to 4000 psig and the flow rate is about 750GPM to 1250 GPM. Fluid coking is a continuous process which consists of 2 units, reactor and furnace. In the reactor, the coke particles are fluidized by steam. The preheated feed will be injected directly into the reactor when it reached temperature of 2500C to 3500C. The temperature inside of the reactor is around 4800C to 5700C. On the surface of the coke particles, cracking process is occurred, causing the lighter components are being vaporized. To separate the entrained coke particles with the vapors, cyclones are used. The vapor is then sent to the bottom of the scrubber and condensed into heavy tar; meanwhile the remaining coke is removed and recycled back to the coke reactor. The overhead of the vapor is directed to a fractionator where it is separated into the desired boiling point fractions. Then the coke particles flow to the stripping zone to remove any product vapor between the coke particles. After that, the coke particles are sent to the burner. A part of the coke is burned to remain the average bed temperature. Hot coke is then sent back to the reactor. To maintain the coke inventory in the burner, coke which is one of the products, required to withdraw from the burner. The large coke particulate will be replaced by the smaller seed particles to prevent the circulating coke is too coarse. Compare to delayed coking process, fluid coking will be carried out at a more uniform and higher temperature and shorter contact time. The products produced by using fluid coking process are more valuable and less coke.

Effect of Spina Bifida on Different Age Groups

EFFECTS OF SPINA BIGIDA ON DIFFERENT AGE GROUPS Individuals who are affected with spina bifida are faced with many difficult challenges. The social factors are different in each age group (newborns to infants, toddlers and preschoolers, school aged children, adolescences, teenagers, and adulthood). Nevertheless, finding resources in your community, knowing what to expect, and planning for the future can help increase confidence in managing spina bifida, enhance quality of life, and assist in meeting the needs of all family. Spina bifida affects the entire family.People who are affected by spina bifida get around in many different ways. This may include walking without any aids or assistance; walking with braces, crutches or walkers; and using wheelchairs. Some people with spina bifida have difficulty picking up the verbal and non-verbal cues necessary for social skills. Some of the areas that might be difficulty for them are talking over differences without getting angry, persistence when facing frustration, taking turns while talking, understanding social rules, demanding immediate attention, and waiting when necessary.However, finding resources, knowing what to expect, and planning for the future can help. No two children with spina bifida are exactly alike. Children’s health issues will be different for each child. Some will have issues that are more severe than other children. With the right care, children born with spina bifida will grow up to reach their full potential. NEWBORNS AND INFANTS In many cases, infants and children with spina bifida require early and frequent hospitalization. This can interrupt normal social development.The challenge is to balance medical needs with the need to let a child develop into a confident, self-sufficient and independent adult. Regular and physical activity is important for all babies, especially for those with conditions that affect movement. There are numerous ways for babies with spina bifida to be active. Ne wborns and infants can be active by: * playing with toys, such as activity mats; * enjoy parks and recreation areas; * participating in community programs, such as the Early Intervention Program for Infants and Toddlers with Disabilities, which is a free program n many communities; and * do exercise with physical therapist. TODDLERS AND PRESCHOOLERS Life with a toddler or preschooler is both fun and challenging. These young children experience huge mental, social, and emotional changes. They have a lot of energy and enthusiasm for exploring and learning about their world and becoming independent. Since developing independence can be particularly trying for children with spina bifida, parents should begin helping their child develop independence early in childhood.The achievements can be measured one by one; building blocks are an effective way to think of them. In the early years, moving about and exploring things with the eyes, mouth and hands are the elements of independence for t he toddler. Parents and other caregivers can help them become more active and independent by: * educating the child about his or her body and about spina bifida; * encouraging the child to make choices, for example, have them choose between two items of clothing; * asking the child to assist with daily tasks, such as putting away toys.Children with spina bifida might require extra help at times. It is very critical that children be given the opportunity to fulfill a task before help is given. It is also important that parents give only the help that is needed rather than helping with the entire task. Parents must become skilled at learning the difficult balance between giving the right amount of help to increase their child’s independence and confidence, while simultaneously not giving the child tasks that cannot reasonably be completed? which might decrease their child’s confidence. School agedSchool connects children regularly with the larger world. Friendships becom e important and physical, social, and mental skills develop quickly during this time. Children who feel good about themselves are more able to resist negative peer pressure and make better choices. Many children with spina bifida do well in school but some can experience difficulties at school. There are children with learning disabilities (water on the brain), struggle with paying attention, work slowly, be restless, or lose things. They also might have difficulty making decisions. There are activities that children an do both at home and at school to help with these problems. These children might struggle with activities which lacks opportunity to socialize with peers. Children with spina bifida have fewer friends and spend less time with peers than typical developing children. Many social difficulties tend to be stable into adulthood. Fortunately, with the proper medical care, children with spina bifida can lead active and productive lives. Many children with spina bifida are suc cessful in school and many are actively involved in modified sports activities despite their physical challenges.With recent progress in care for these children, their outlook continues to improve. This is a significant time for children to become more responsible and independent. This is also a good time to start exploring potential lifetime interests such as hobbies, music, or sports. Acquiring independence can be challenging for people affected by spina bifida. It is important to begin working on this process early in childhood. Physical activity again is important for children of all ages, but especially for those with conditions that affect movement.For example, they can: * engage in active play with friends; * roll or walk in the neighborhood; * enjoy parks and recreation areas with playgrounds that are accessible for those with disabilities; * attend summer camps and recreational facilities that are accessible for those with disabilities; and * participate in sports activitie s and teams for people with or those without disabilities. Children with spina bifida often cannot control when they go to the bathroom (incontinence).They also can develop urinary tract infections. It is important to develop a plan for going to the bathroom that works and is as simple as possible. This can lead to increased health, participation, and independence at school and in the home, and avoid embarrassment for children with spina bifida. ADOLESCENTS AND TEENS Many physical, mental, emotional, and social changes are associated with the adolescent and teen years. Teens and adolescents develop their own personalities and interests and want to become more independent.It is important for the parents and caregivers of adolescents and teens with spina bifida to take effective steps toward making them independent starting in childhood, so that by the time they are older they can develop the necessary skills to help them reach their full potential. Physical activity is important for all teens and adolescents. There are several ways for teens and adolescents with spina bifida to be active. For example, they can: * engage in physical activities with friends; * roll or walk in the neighborhood; * lift weights; participate in sports activities and on teams for people with and those without disabilities; and * attend summer camps and recreational facilities that are accessible for those with disabilities. YOUNG ADULT The transition from adolescence to adulthood can be a time of progression and success, as well as difficulty. For people with spina bifida, it is specifically vital to begin planning for transitions in childhood so they are able to lead independent lives as adults. Young adults affected by spina bifida can face challenges, such as: * learning to take care of their own health needs; working or continuing their education; * volunteering; * finding and using transportation; * living outside their parents’ home; and * obtaining healthy relationships. Young adults can provide or manage much of their own care. Some instances include: * finding new doctors that care for adults affected by spina bifida; * obtaining medical insurance if they are no longer covered under their parents’ health plan; * talking to health care professionals about their condition; * making doctor appointments; * ordering or reordering medications and supplies; * seeking immediate medical help when needed; and managing their own bathroom plan. There are many ways for people with spina bifida to be active. Such as: * roll or walk in the neighborhood; * lift weights; and * participate in sports activities and teams for people with or those without disabilities. Transportation is important, young adults need to be able to find and use transportation safely. Many adults with spina bifida have problems that can affect safe driving. They may need a driver rehabilitation evaluation specialist in order to identify if special changes are needed to a car to ma ke it accessible for driving by someone with spina bifida.Adults also can learn to find and use other transportation safely, such as buses and cabs. Being safely mobile in their homes and communities will help adults become more independent. As adults plan for employment, college, or vocational training, they need to find and use transportation safely. Many young adults are still getting used to their new independence. They may have started working, volunteering, going to college or other training, or living on their own. Nonetheless, continuing to plan for the future is very important.This involves setting goals and how to achieve them. At times, unexpected problems can make life difficult. It is important for them not give up and to keep moving towards their goals, even if their goals sometimes need to be modified, or take longer than planned. Planning now will help adults continue to grow and succeed as they get older. In summary, people with spina bifida will face lifelong medic al challenges associated with this disorder, and the emotional and financial effects that the family will endure are overwhelming.In the United States, children born with spina bifida often live long and productive lives, even though they face many challenges. Though individuals reported having a high quality of life, they also described facing challenges and barriers that affect their ability to fully engage in life experiences. Individuals of all ages from birth through young adulthood reported experiencing common physical challenges such as pain, skin break-down, pressure sores, mobility limitations, latex allergy, and difficulties with endurance and balance.Some individuals between the ages of 6 and 18 years reported having scoliosis and breathing difficulties, during a time of rapid growth. As youth reach the teen years through young adulthood, many also reported difficulties with weight gain and concern about sexuality. Although individuals with spina bifida may experience sec ondary conditions, the role of support has shown to be a large factor that minimizes these challenges. Family support has been reported as a critical component as well as support given to families from outside sources such as friends, relatives, churches and other community groups.These supports have shown to help reduce secondary complications for individuals with spina bifida as well as ensure that they can participate fully in life activities and experiences. While individuals with spina bifida face many challenges growing up -whether they are social, physical, or academic -remember that the person with spina bifida is first and foremost a person with similar desires, likes, talents, frustrations, and concerns as all people. They will experience the same developmental milestones as all individuals -from saying â€Å"NO! in the toddler years, to becoming more independent and social in the teen years, to thinking about relationships and employment in the adult years. We are privil eged to live in a time of positive change and opportunities for people with disabilities. Expectations are changing for the positive to include individuals with disabilities in all facets of community living. Regrettably, change is usually a slow process and many of the physical and attitudinal barriers of society have not kept speed with the new positive expectations.

Mariachi Music Research Paper Essay

Mariachi music originated in Jalisco, Mexico. It is said it began in the town of Cocula. It is a version of theatrical orchestra, it includes violins, harp and guitars which developed in and around Jalisco. It began in the 19th century, and is still popular today. The Violin is apart of a Mariachi ensemble, it is a string instrument. It is 4 stringed and the smallest, highest-pitched member of the string family. The purpose of the violin in mariachi music is to complement trumpet melodies. The most important element of this style of playing to use the entire bow. The Vihuela also plays a major role in a Mariachi ensemble. The Vihuela is an instrument that is basically two different guitars ring instruments. The one played in the Mariachi band is from the 19th century. It has 5 strings and originated from Mexico. There is another one from the 15th and 16th century, that one originated in Spain. That specific Vihuela typically had 12 strings. The Guitarron is a very large, deep bodied Mexican 6- string acoustic bass. It is similar to the guitar developed from the 16th century. The Guitarron is typically played by doubling notes by octave. The Guitarron is used to keep the beat and other instruments together. The trumpet is apart of the brass family, it has the highest register out of all the other instruments. It is played by blowing air threw closed lips. The trumpet replaced the cornet in the mariachi band, now there is usually two trumpets in a mariachi band. The trumpet combination in mariachi was popularized in the 1950s. There are many characteristics to mariachi bands. The forms found in mariachi music are, the most important element of the style. Mariachi song forms (such as the bolero, cancià ³n ranchera, son, huapango, joropo, and danzà ³n) are always the rhythmic patterns that are performed by the guitar section of the group. There is also singing involved in mariachi music. For example, the â€Å"grito mexicano†, a yell that is done at musical interludes during a song, either by the musicians and the listening audience. Like of that would be the mariachi players singing â€Å"AY YA YAY YA!†

New Geological Discoveries The Last Couple Hundred Years

We live in a relentless society characterized by spectacular scientific innovation and research. This innovation continuously morphs the foundation of how we understand the world, including our philosophical ideologies and religion. New geological discoveries the last couple hundred years has undermined many Literal-historical views on how the earth was created. Churches that were once anchored on the young earth hypothesis now face a split between those who hold steadfast to their traditional foundation, and those two branch out their beliefs to accommodate the scientific discovery. A multitude of theories such as the Day-Age, Gap and Framework have come up from the mix of postulations. Before I came into this class, I had begun to develop my own notions about the way in which the world was created, but had a very unclear picture of how the flood, radiometric dating, and layers of sediment played into the whole picture. My ideas were congregated from a mixture of what I was tau ght at my modern evangelical church, what I had learned in public school, and what I had read in scripture. I however, faced a discontinuity within this area because while I knew what I believed, I didn’t know why understanding this issue mattered. Thanks to this discussion about Genesis and geology, I have developed a clearer picture why and how I believe in certain theories and philosophies. 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