Friday, September 6, 2019
Work From Home Essay Example for Free
Work From Home Essay Are you tired of the common grind you must deal with on a daily basis? Does you current job leave you with limited career and salary opportunities? If so, have you thought of going into business for yourself and working from home? Now, some may assume that such an option is really not possible and that all those advertised work from home pitches are gimmicks and scams. Well, the reality of the matter is that working from home is the wave of the self-employed future and it brings with it a number of opportunities to earn significant income. One of the best resources for earning additional income working from home is Poly Promotions ProfitableJobs. com as it provides a multitude of ideas for wealth creation. Often, many of the ideas offered by ProfitableJobs. com are relatively simply concepts that are often overlooked, but are also consistently successful. In todays day an age, there are a number of options that are available to people that previously did not exist prior. Because of the great expansion of the internet and other forms of communication the ability to work from home has become a reality. Of society has shifted many times over the past centuries as it has gone from an agricultural based society to an industrial based society and now to a technological based society. In the past, there were no home computers, notebooks or iPods. Today, because we have such great access to a number of technological/communicative devices the ability to work from home differs very little from heading into the office to work. This has opened a plethora of financial opportunities for an individual to take advantage. Every week after initially signing up, ProfitableJobs. com will send you a series of email tips for work at home money making opportunities. Most of these opportunities involve very little start up money and are not complex ventures to take part in. As such, there is no reason not to take advantage of these opportunities as they bring a variety of benefits not the least of which may be financial independence.
Post-traumatic Stress Disorder in Soldiers in Iran Essay Example for Free
Post-traumatic Stress Disorder in Soldiers in Iran Essay Abstract            The conditions of post-traumatic conditions have been one of the major side effects on soldiers engaging wars and negative environment in the area of Iran. The psychological impact of this event involves various manifestations that prove to be non-beneficial and may even impair the psychological, mental, emotional and physical health of these soldiers. Even though the condition is widely known, the advent of social conflicts and emerging wars in the Pakistani- Iran environment has continuously caused the negative trauma among soldiers facing the threats. Post-traumatic Stress Disorder (PSTD) in Soldiers in Iran Introduction            In general psychological perspective, soldiers who engage in war with exposure to at least one battle can suffer trauma. The longer the exposure to war’s traumatic circumstances the deeper the post-traumatic sense of a life-death continuum that rests at the heart of the PTSD syndrome. Soldiers with exposure to trauma would experience various post-traumatic states. In a military culture that emphasizes courage under fire, counterphobic impulsivity would dominate as the ideal mental and emotion state, and promoted the aggressive personality. Each soldier has a breaking point at which phobia breaks through. In some cases, phobia dominated from the beginning. The point at which the soldier’s spirit broke would lead to a state pf phobic withdrawal. In either case, the exposure to battle or an environment where death and dying by implements of war were common would create a life-death continuum (Reid, 2001 p.427).            As soldiers rotated home or were sent home wounded, difficulties became apparent. While many came home and resumed their lives, some brought home drug dependencies and emotional problems, including explosive anger, distrust of others and vigilance beyond what was considered normal. The problems came to the attention of the medical groups, Andover time, doctors and psychiatrists began to elaborate on the concept of traumatic stress and PSTD (Roberts, 2003 p. 6). The most immediate effects of traumatic scenarios are manifested in the sensory that causes overload through sudden exposure to the bewildering, often exotic details of a much less advanced and alien society. Iran-American soldiers are both victims of the traumatic events experienced in the war; thus, engages these individuals in PSTD. Discussion PSTD: An Overview            What is now referred to as PSTD has been around since recorded history under many different designations and description, and the most prominent manifestations are for those individuals who engage in traumatic events, such as war and deviant phenomenon (Lewis, 2006 p,63). PSTD occurs in response to the personal experience of overwhelming, terrifying, potentially lethal stress directed toward oneself or someone with whom the individual has a close attachment. The condition is a unique mental disorder that develops directly as a result of exposure to some type of trauma (Lewis, 2006 p,62). Examples of possible precipitations of PSTD would include severe automobile accidents, being raped or assaulted, and being exposed violent events. The individual then re-experiences the event in various ways, such as recurrent stressful recollections of the event, dreams of the event, and a sense that the traumatic event may be occurring again. The individual then attempts to avoid such cues in different methodologies, such as numbing of responses or becoming distant and removed (Mitchell, 2001 p.107).            In the field of traumatic stress studies, it has been common, if not traditionally accepted, to define trauma by the nature of the stressors that influence the individual. Psychologically traumatic event can be construed as one in which the person has experienced an external stressor event that is injurious to the normal state and results in a condition that reflects this injury to the pre-traumatic state of being (Lewis, 2006 p,62-63). Thus, the injury caused by a traumatic event could produce varying degrees of distress to the victim for varying lengths of time, depending on the nature of the person, the nature of the traumatic experience, and the personal and social resources available for recovery and re-stabilization of the psychological state (Williams, 1994 p.7). PSTD is an unusual emotional disorder in that unlike disorders, such as depression and panic disorder, it is not defined simply in terms of its symptoms. To qualify for a diagnosis of PSTD, an individual must be exposed to an incident in which he or she feels that his or her life, safety, or emotional integrity has been seriously threatened. Often, for victims who have experienced a traumatic event, they may first be diagnosed with an adjustment disorder or an acute stress disorder (Lewis, 2006 p,62). Wars have provided a setting where large numbers of soldiers, subjected to varying degrees of stress, could be observed and studied by physicians of the period. The stress caused by war has been codified and labeled with such terms as: combat exhaustion, traumatic war neurosis, war or combat stress and, most recently, PSTD (Scrignar, 1991 p.87). Assessing traumatic experiences and understanding their impact on the trauma victim involve determining what is stored in the trauma network. While keeping the stimulus, response, and meaning dimensions in mind, the clinician should listen carefully to the clients account of the trauma, and then inquire explicitly about memory elements that are absent or de-emphasized (Williams, 1992 p.24). PSTD symptoms are generally grouped into three categories (Lewis, 2006 p,63) Re-experiencing includes disturbed sleep, intrusive memories, distressing dreams, nightmares, flashbacks, reliving the event, a view of the world as unsafe. Numbing and avoidance mistrust of others, isolation and disconnection, emotional or psychic numbness, low self-esteem, neglect of health, dissociation, ability to remember memories or feelings but not both, memory loss for certain events, loss of faith and hope. Hyperarousal – intense emotions, difficulty sleeping, panic and anxiousness, self-harm, risky behaviors, irritability, anger, difficulty concentrating. PSTD: Sufferings of the Soldiers            In the aftermath of September 11, many parents and educators have struggled to help young people cope with traumatic events and have sought out ways to teach about crises without causing more trauma and stress. The conflict between Iran and United States has been pushed to its very limits; hence, initiated catastrophic moves during 2001 up to present, which caused the another class of America-Iran war. Many studies conducted by the American Psychiatric Association indicated that many American soldiers experience post-traumatic stress disorder, which follows a psychologically traumatic event outside of the range of usual human experiences. The symptoms may include nightmares, depression, withdrawal, hopelessness, sleep disorders, and other somatic complaints. The terrorism of September 11, 2001, and its association with Afghanistan have only added to the stress faced by the soldiers as well as the refugees living in the area as well as United States (Andrews and Boyle, 2002 p.328).            Military psychologists have long known that fear, stress, and exhaustion cause more casualties than do bombs and bullets. The ratios of psychological to physical casualties can be enormous considering the fact that war-related trauma is potentially severe, repeated and prolonged. Many American soldiers who fought for Iran and Afghanistan war during terrorism counter-siege have experienced immense manifestations psychological torture. According to psychological analysts, the primary goal of terrorism is to inflict psychological trauma for political ends. The exploitation of terror for political purposes is hardly new, when the French government employed terrorism to buttress the revolution (Allen, 2005 p.9).            According to statistics issued by United States Army of mental health, 76% of soldiers have been traumatized by deaths or severe injuries of individuals close to them, while 55% of the soldiers have experienced near-death situations (e.g. bomb explosions, bomb trap, and roadside explosions). These causations have been deemed as the primary contributor to the occurrence of the said conditions (Weinstein, 2006). The table below shows the decline and rise of lethality, fatality and psychological trauma caused by the terrorism in the surveyed American military force. Table 1. Decline and Rise of Lethality, Fatality and Psychological Trauma Caused by the Terrorism Year U.S Dept. of State # Incidents U.S. Dept. of State # of Fatalities U.S Dept. of State #. Psychologically Traumatized 1994 322 314 663 1995 440 177 6,277 1996 296 314 2,915 1997 304 221 693 1998 273 741 5,952 1999 392 233 706 2000 423 405 791 2001 567 * 50,000 8,902 2002 663 * 20,000 16,321 Note: * Data are crude estimates only since, the number of fatalities is yet to be determined due to lack of data available. Source: Das and Peter, 2003 p.43-44            The table above shows variably rising and falling statistics with certain timeline that determines the probable cause of the rise and fall. For example, the recent terrorism attacks of 2001 has caused immense fatalities, and the number continued to progress but greatly lowered since most of the fatalities during 2002 are mostly from military activities. However, sad to say, the number of those who has been traumatized increased in two-folds due to the war that these military powers engaged. The trauma caused by war caused psychological impact due to trauma among these soldiers as manifested by the table statistics above; hover, PSTD may not be the sole classification of the trauma caused by the said impact. Other psychological trauma-related conditions have been reported to occur in these soldiers, such as phobia, severe anxiety disorders, etc (Das and Peter, 2003 p.45-46).            Post-traumatic conditions have been found to most of the soldiers that entered the episodes of war. Only recently (2006), the Ministry of Defense has decided to reward $375,000 upon membership to Armed Forces who have suffered PSTD from Iraq-American wars (Evans, 2006). The federal government has allotted these funds in order to provide free treatment of those soldiers who incur physical and psychological damage from the field, such as those with PSTD. Medications for PSTD patients, such as Fluoexetine, sertraline, paroxetine, propanolol, have been provided by the government in order to ensure the treatment progression of these soldiers. Furthermore, psychological counseling, treatment and management for remedy of phobia or trauma have been initiated through federal government’s grants (Weinstein, 2006; Evans, 2006). References: Allen, J. G. (2005). Coping with Trauma: Hope Through Understanding. American Psychiatric Pub. Andrews, M. M., Boyle, J. S. (2002). Transcultural Concepts in Nursing Care. Lippincott Williams Wilkins. Das, D. K., Kratcoski, P. C. (2003). Meeting the Challenges of Global Terrorism: Prevention, Control, and Global Terrorism. Lexington Books. Evans, M. (2006, November 17). MoD agrees  £375,000 for post-trauma stress. Retrieved January 10, 2008, from Times Online: http://www.timesonline.co.uk/tol/news/world/iraq/article1087438.ece Lewis, G. W. (2006). Organizational Crisis Management: The Human Factor. CRC Press. Matiolli, D. J. (2003, January). War with Iraq. Social Education, 67, Mitchell, J. (2001). Points of View: Stories of Psychopathology. Psychology Press. Reid, J. J. (2000). Crisis of the Ottoman Empire: Prelude to Collapse 1839-1878. Franz Steiner Verlag. Roberts, C. A. (2003). Coping with Post-Traumatic Stress Disorder: A Guide for Families. McFarland Company. Scott, M. J., Stradling, S. G. (2000). Counselling for Post-Traumatic Stress Disorder. SAGE. Scrignar, C. B. (1991). Stress Strategies: The Treatment of the Anxiety Disorders. Wellness Institute, Inc.. Weinstein, M. N. (2006, January). The Psychological Dilemma of Terrorism Post 9-11. Annals of the American Psychotherapy Association, 3, Williams, M. B. (1994). Handbook of Post-Traumatic Therapy. Westport, CT: Greenwood Press.
Thursday, September 5, 2019
Knife Gun And Gang Crime In East London Criminology Essay
Knife Gun And Gang Crime In East London Criminology Essay In this Project I will be writing about crime in East London. The main reason I chose to do Crime was because crime has been a key factor in how it has affected many people across the world. The types of crime I will talk about are Knife, Gun, and Gang. East London is located in London and an easier way to find it is by any post code as anything beginning with E is part of East London. In general East London is a very multi-cultural society with many sets of group living there and in it you can find something from all parts of the world but recently, over the past 3 years has been hit by a number of crime related incidents which have affected many people in the area from the young to the old. I will now write about crimes which occurred over the past 20 years and give examples of some I will also define the meaning of each crime and also the word crime, so that people know what they mean. The word Crime can simply mean an action that breaks the law but different people have different opinions of what they think of the word crime: The three main types of crime I will talk about are knife, Gun and Gang. Knife crime can be any crime that involves a knife. This could include many aspects such as: carrying or trying to buy a knife if youre under 18, threatening people with a knife, carrying a knife that is banned. Knife Crime in the Past 20 years wasnt such a major problem because knives were not easy to get hold of and the main purpose of having a knife was for home purposes such as cooking etc. The most common knife crime was committed in the very early 70s by a person who was known as Jack the ripper, who killed more than 5 people by raping his victims and slicing their throats with a knife and hiding his victims under the floor boards in plastic bags. Gun Crime can be anything that involves a gun for example a murder where the victim is shot, any situation where a gun is fired, intimidating people with a weapon, carrying a gun that is banned, such as a handgun, carrying or using an imitation gun such as a plastic or toy gun. In the 17th century a series of gun related crimes were committed in the East London by the person called Thomas Hopkins, in which he kidnapped people who had caused him grief and trouble in his childhood and took them to his house where he put them through pain and eventually killed them by shooting them through the brain blowing their heads off. He had 3 victims killed before soon realising that no one could help with his illness and he shot himself to death on the 4th of March 1799. Gang crime could be a gang in a large group of people who maynt be involved in crime and violence. Many young people will not realise they are in a gang, they will just think they are in a group of friends. Being in a gang is not illegal only the criminal offences committed within the gang is illegal. The most commonly known gang crimes were committed in east London by two people who were also bothers named the Kray twins, (Ronnie and Reggie). They worked together to commit a number of violent assaults, arson, armed robberies and other organised crimes. They were known as the East End gangsters and the Godfathers of Britain. Both sets of bothers were sentenced to imprisonment once found guilty by the police. Since then they both have died. In this section of my project I will talk about the crime in East London in the recent years. It is quite obvious that crime compared to the past 20 years has increased and below I will talk about why it has increased and give some examples of people who have been affected by the type of crimes. Figures and research show that crime has increased by 25% in the East London with Knife and Gang crime being the highest of number of Crimes committed. Knife Crime in East London has recently increased from the past. This is down to an increase of Gangs and easier ways to get in possession of a knife. An example of knife crime in East London was On Sunday 7th October; a boy was stabbed to death when he tried to stop a gang stealing a friends mobile phone in West Ham Park. It was due to him protecting his friends and was innocently stabbed and died on the scene. The reason why people especially young people may carry knives around is due to the number of Knife crime happening in the area, and in order for them to feel safe and secure they carry a knife around with them or if they are part of a gang it could have been pressured on them to carry one or as the rest of the gang may have one, then the young person has to have one to feel as if they are part of it and not left out, and in case anyone tries to stab them or attack them with a knife they have something to use against the attacker. Gun Crime is a lot fewer then Knife crime. A boy from London has made British criminal history by becoming the youngest person to be convicted for possessing a firearm. The boy, aged 13 at the time and cant be named for legal reason, said he was storing a Russian-made pistol, two silencers and ammunition in his mothers home as a favour for an older gang member. Many people will not carry a gun on them, but may be in possession of one or may know somewhere where one is easy to get hold of. Gun Crime is not so common is East London as it has been harder to get hold of guns and find them. The largest number of gangs in East London are said to be in Hackney, (22 gangs); Enfield in north London (13); Lambeth and Merton in south London (12 gangs each); Waltham Forest(8) in north east London. Gangs are found to have around 20 to 30 members and to commit crimes in smaller groups of three to six, as being in a large group could get people suspicious. Religion was also found to be a key factor, with some gangs solely being just Muslims or Catholics members and there is rather few gangs with a mixture of race and religion in them as people feel a mixture of people in a gang cant be trusted. A former gang leader said some young people became gang members in order to feel protected. They feel safe in a gang because you have got older people in the gang who are always going to look after them; they feel like we are their olders almost like brothers and family member. You are always moving as a pack. Its as you fight in a war people out there in the world are out to come after us and take us down we have to keep on the move. It is very common that if you find a large gang that someone normally the higher rate leader will be in possession of a gun for safety purposes or to use in case of a gang feuds. There is one other Main issue why gang crime has increased and has been created in East London and this is down to which postcode they live in. Teenagers marked as E5 or E9 were at risk of being attacked for straying into the wrong area. Simply crossing to the other side of a street which borders two postcodes could end in violence. An Example of these post-code gangs is that one teenage girl has been a victim of two attacks due to the area she comes from and the area she went into. The Most common way of people asking where the people are from by asking What Ends are you from? giving a wrong answer at this point could have you attacked or mugged. The reason why this happens is that Gangs feel like their area is their territory and that no one should cross, especially people from opposite postcode. This Type of gang crime has become so bad people dont feel safe walking through some areas and have to find alternative routes to get home etc. Unfortunately some people are unaware that they may be in a gang, a large group of friends could be hanging out together, something which may be normal to them, but people may feel that they are in a gang as people walking past may feel intimidated by the size and feel unsafe. So it shows you that you dont need to be committing crimes in a gang to be classified as being in a g ang. All crimes are related to each other in some shape or form. Due to the increase of Knife Crime and overall crime more and more people are joining gangs to feel safe and have people protecting them. These gangs cause crime and will carry some sort of weapon with them normally a knife and maybe a gun. So all these types of crime are linked within each other. Many things have been done to reduce crime in East London. A new law was created by the government that police have the right to stop and search anyone they think might be in possession of a weapon or look suspicious. Many people have their own point of view on this topic. Some people think that it is inappropriate as police says its a random stop and search. While they could be searching someone by random who is innocence someone else carrying a knife would not being searched as and walking about with a Knife. I personally have been stopped and searched and think its a time consuming process and waste both mines and police time as I know that Im not carrying a weapon and the police time as they not find nothing on me. Tougher sentence have been put in place for people who carry a knife or stab or kill someone using a weapon, as more people would know that they cant get away. There is more surveillance put in place as more police officers have been put on patrol on the streets to hel p reduce the crimes and make the public feel safer. Also another new law that has been created by the government is the rise in the age of people who can buy a knife as now people have to be over 18 to be able to purchase a knife from a shop. This law allows young people from being able to stop them from buying a knife and going out and using it. Even ASBOs (anti social behaviour order) have been given to some gangs and gangs members to try to make them stop hanging around in large groups and causing trouble but some people think that ASBOS are a tag of pride and use it to show people that they have it and show off about it thinking it is a good thing and its not working for the police. Thats why many more police officers are patrolling the streets of East London to stop large groups hanging around and try to get them to move away from residential areas. The reason why crime occurs in east London I think is due to poverty as people dont have money so they go out and commit crimes to ensure that they get money and the things they need. So doing these crimes would make them money or stealing from people by using a knife to threaten them to hand over their items. So I think money and greed are the biggest motivation why so many people go out there and commit crimes. Poor upbringing is another reason why people who have failed in life or no longer attend school or college for reasons like being excluded from it are more likely to go out and commit crimes. Has they dont have anything to do and they know that they dont have a good future ahead and some believe that prison life is much easier than the real world. Also some people think that crime is the easier option to take in life as its easy money to get hold of. The way crime has increased over the time has affected the world, as East London is such a multi-cultural area; many people want to come over to East London from all parts of the world. The people have heard about the crimes that have occurred in east London, which may make them feel unsafe as they would be new to the country, and make them reconsider about coming over in case they get caught up in any of the crime. The reason why crime has stayed on the increased and not gone down since the past is down to not harsh enough punishment given to the people who get caught. So if someone was caught committing a crime and faced a punishment they would know that they wont get away and make them re-think about not going out and committing the crimes as they would know that the punishment would be a substantial one. I think that the crimes that are occurring in east London are unnecessary and only just giving a bad name to East London and I think that East London will not be the same for a very long time as crimes if nothing is done to make them stop. All these crimes are affecting peoples live; people who live here are worried over their safety and outsiders who want to come over for a holiday or to live and will think twice. I think that the only way crime can be stopped is by getting the police to do more. Crime in East London hasnt really affected me in a way that much. The only way it has affected me is that all crimes that happen get blamed on the young people and I am one of the young people so even people who arent committing the crimes get given a bad name.
Wednesday, September 4, 2019
Social Darwinism: Herbert Spencer and The Catholic Church Essay
Herbert Spencer was the most important Social Darwinist of the 19th Century. He was the first to begin thinking about evolutionist long before Darwin came out with his book on the "Origins of Species". He had many theories such as that everything evolves from one basic creature and then breaks off into more diverse species (Haberman (Hab.), 171). His theory was that social, political, and intellectual movements were caused by the development from the homogeneous to the heterogeneous. Spencer once stated, "If the advance of man towards greater heterogeneity is traceable to the production of many effects by one cause, still more clearly may the advance of society towards greater heterogeneity be so explained" (Haberman 2 (Hab2)) Spencer believed that governments should not try to change social environment, for it would hamper with processes of nature and individual liberty (Hab). He had a theory that evil would disappear if "every man may claim the fullest liberty to exercise his faculties"(Hab). Although this would onl...
Tuesday, September 3, 2019
The Fool And Cordelia: Opposing Influences On King Lear :: essays research papers
Although the Fool and Cordelia are similarly candid towards their King, they never interact in Shakespeare’s King Lear, because the Fool is a chaotic influence while Cordelia is a stabilizing force. While the Fool and Cordelia both act in the Lear’s best interest, it is not always evident to Lear. The Fool’s actions often anger the King, and lead to an increase in his madness. On the other hand, Cordelia’s actions more often soothe Lear, and coax him back into sanity. Another commonality between the Fool and Cordelia is their honesty. Both the Fool and Cordelia are frank with Lear, though he may not always appreciate that they do so for his own good.      In Shakespeare’s King Lear, the Fool is a source of chaos and disruption in King Lear’s tumultuous life. The Fool causes the King distress by insulting him, making light of his problems, and telling him the truth. On the road to Regan’s, the Fool says â€Å"If thou wert my Fool, nuncle, I’d have thee / beaten for being old before thy time.†(1.5.40-41). He denies the king the respect due to him as an aged King, causing the King to wonder at his worthiness. The fool also makes light of Lear’s qualms making snide remarks in response to Lear’s ruminations. When Lear asks Edgar cryptically, â€Å"wouldst thou give ‘em all?†the Fool responds, â€Å"Nay, he reserved a blanket, else we had been all shamed†(3.4.69-72). The Fool’s snide remarks do little to maintain Lear’s fragile control of his faculties. However, the Fool speaks to the king candidly, a rare occasion in Lear’s life . Even Kent acknowledges the truth of the Fool’s statements, saying, â€Å"This is not altogether fool, my lord†(1.4.155).      While the Fool disrupts Lear’s mental state, Cordelia steadies him with compassion, understanding, and truth. When Cordelia has rescued the King, she says that â€Å"Mine enemy’s dog, / though he had bit me, should have stood that night / Against my fire†(4.7.42-44). Cordelia is amazed at her sisters’ treatment of Lear because she cannot comprehend the actions of such uncaring people. Cordelia’s considerate nature soothes the King’s overwrought mind. Because the King seems rash and even irrational at times, those who understand him are few. His youngest daughter knows what Lear goes through with her sisters, and wishes that she could â€Å"Repair those violent harms that my two sisters / Have in thy reverence made.
Monday, September 2, 2019
Accounts of Attila :: Rome History Attila Essays
Accounts of Attila Works Cited Missing In Priscus’ 449 account, Attila behaves as a leader who does not merely rival the Roman Emperor, but is in fact superior to the Emperor. Furthermore, he exhibits both Roman and barbarian traits. In addition, Priscus does not use the same vocabulary as utilized in the â€Å"Anonyomus Account†to describe Attila. That is, Attila is not depicted as a brutal barbarian warlord or a savage pagan; rather, he is depicted as a leader who is familiar with Roman customs, in possession of luxuries similar to those of Rome, and skilled at political intrigue and manipulation. Priscus’ account is similar to Prosper’s account as it seems to be relatively objective and merely explains the events that transpired (outside of Priscus’ obvious bias, as he was a civil servant and championed the promotion of the Roman systems of law, taxation, and self defense to the Greek Scythian – Priscus, 204). Additionally, Jordanes’ account is similar to the †Å"Anonyomus Account†because they are both subjective (i.e., Jordanes depicts Attila favorably; while he is apparently held in ill favor by the author of the â€Å"Anonyomus Account†). Moreover, all four sources have one theme in common: Attila was perceived to be a legitimate threat to Rome. Attila’s treatment of the Roman embassies in the beginning of Priscus’ account shows that Attila was not afraid to treat the Roman delegation rudely. Indeed, he refused to meet the ambassadors himself and sent his emissaries to do so, although he knew this was not the Roman custom and his ambassadors had received proper treatment on previous occasions in Rome (Priscus, 202). Furthermore, Attila had been known to claim that, â€Å"his own subjects were generals of [Theodosius] and that his own generals were of equal worth to the Emperors of Rome†( Priscus, 206). Thus implying that he believed he was superior to the Emperor. In addition, Attila was so bold as to demand Ambassadors with higher ranks (Priscus, 206). Attila exhibited Roman and barbarian traits. Unlike the Emperor, who led a republic, he was a barbarian king who ruled over a Monarchy. In addition, Attila differed from the Emperor since he was a warrior king who carried arms and participated in battle as evidenced by Jordanes’ description of his participation in the battle on the Catalaunian Plains (Jordanes, 101-104).
Sunday, September 1, 2019
My Final Year Project
A REPORT ON AUTOMATED STEAM JACKETED COOKING VESSEL BY PRATAP DESHMUKH 2008A8PS251G AT GADHIA SOLAR ENERGY SYSTEMS PVT. LTD. A Practice School II station of BIRLA INSTITUTE OF TECHNOLOGY & SCIENCE, PILANI (JANUARY – JUNE 2012) A REPORT ON AUTOMATED STEAM JACKETED COOKING VESSEL BY PRATAP DESHMUKH 2008A8PS251G B. E. (Hons) ELEC. & INSTR. Prepared in partial fulfillment of the requirements of the Course No. BITS C412 (Practice School II) AT GADHIA SOLAR ENERGY SYSTEM PVT. LTD. A Practice School- II station of BIRLA INSTITUTE OF TECHNOLOGY & SCIENCE, PILANI JANUARY – JUNE 2012) ACKNOWLEDGEMENT I would like to thank the Managing Director and Coordinator of Gadhia Solar Energy Systems Pvt. Ltd. , Mr. Badal Shah, for giving us this wonderful opportunity. I would also like to thank my mentor Dr. Vivek Wasekar, Vice President R&D and Mr. Veera Prasad Gadde Deputy General Manager, R&D, for being a constant source of guidance and support throughout my project. I am also grateful to the Vice Chancellor, BITS Pilani, Prof. B. N. Jain, and the Practice School Division Dean, Mr G.Sundar for giving us this opportunity to gain valuable work experience. I am extremely thankful to our faculty in charge, Mr. Pavan Kumar Potdar for conducting the programme in an effective manner. PRATAP DESHMUKH 2008A8PS251G Page | 0 BIRLA INSTITUTE OF TECHNOLOGY & SCIENCE, PILANI (RAJASTHAN) Practice School Division Station: Gadhia Solar Energy Systems Pvt Ltd Duration: 06 January 2012 – 20 June 2012 Date of Submission: 30 March 2012 Title of the Project: AUTOMATED STEAM JACKETED COOKING VESSEL NAME PRATAP DESHMUKH ID NO 2008A8PS251G DISCIPLINE B.E. (Hons) ELEC. & INSTR. Centre: Valsad, Gujrat. Name of expert: Dr. Vivek Wasekar (Associate Manager, Instrumentation Dept. ) Name of the PS Faculty: Mr. Pavan Kumar Potdar Key Words: Steam cooking, Jacketed Vessel, PLC, Ladder Logic, solar, cooking. Project Areas: A development project of a automated cooking system for steam cookin g vessel Abstract: This report covers the details of the project undertaken by me at Gadhia Solar Energy Systems Pvt. Ltd. to develop and implement the automation of Steam cooking with a steam jacketed cooking vessel.It also focuses on the technical and design aspects of the new system and provides a detail study of observations after implementation of the system (Signatures of Student) __________________ 25 March 2012 (Signature of PS faculty) __________________ 30 March 2012 Page | 1 BIRLA INSTITUTE OF TECHNOLOGY & SCIENCE, PILANI (RAJASTHAN) Practice School Division Response Option Sheet Station: Gadhia Solar Energy Systems Pvt. Ltd. ID No. & Name(s): Pratap Deshmukh Centre: Valsad, Gujrat 2008A8PS251G Title of the Project: AUTOMATED STEAM JACKETED COOKING VESSEL Code No. 1. 2. 3. Response Options A new course can be designed out of this project.The project can help modification of the course content of some of the existing courses. The project can be used directly in some of the existing Compulsory Discipline Courses (CDC)/Discipline Courses Other Than Compulsory (DCOC)/Emerging Area (EA) etc. Courses The project can be used in preparatory courses like Analysis and Application Orientated Courses (AAOC)/ Engineering Sciences (ES)/Technical Arts (TA) and Core Courses This project cannot come under any of the above mentioned options as it relates to the professional work of the host organization. Course No. (s) & Name 4. 5. YES Signatures of Students) __________________ (Signature of PS faculty) __________________ Page | 2 Abstract: Gadhia Solar is an innovative Solar Thermal Energy Company, focused on providing energy solutions by using Parabolic Concentrated Technology, backed by technical support from HTT GmbH of Germany. Since its inception, Gadhia Solar has been a technologically, solution focused company driven by strong passion for environmental and social contribution combined with high creativity and integrity. The company is into researching and dev eloping new alternatives to harvest the unfathomable source of energy.Automated Steam Jacketed Vessel is a new kind of cooking vessel in itself. The vessels used for soalr thermal cooking are one with direct injection of steam and have limited usability. But with jacketed cooking vessel, any kind of food item can be cooked since the food does not come in contact with the steam. For cooking food, the temperature of the vessel should be maintained in the bracket of 80-120OC which will not only cook the food faster, but also won’t burn it. The vessel was designed with the help of Dr. Vivek Wasekar and for automation of the cooking process; I worked with Mr. Veera Prasad Gadde.For the automation, a Programmable Logic Controller (PLC) is being used which will read the temperature inside the vessel with the help of a Resistance Temperature Detector (RTD) and thereby control the cooking process. Two Solenoid Valves are being used to control the flow of steam and the condensate insid e the jacket. And also a pressure regulator is being used to regulate the pressure of the steam from the header. The parabolic dishes will generate the steam inside the header. When the outlet of the header is opened, the steam at high pressure at around 15 bar will be let into the outlet.The pressure regulator will regulate the pressure of the steam to a value of around 3 bar which will go towards first solenoid valve. When the cooking process is started, the first valve will open and let the steam into the jacketed vessel. The steam will raise the temperature and thereby cook the food. For the initial implementation, three food items have been considered i. e. rice, dal and vegetables. According to the food item being cooked, the controller will decide the temperature and time for cooking and proceed with the cooking. The second solenoid valve will remove the condensate from the jacket of the vessel.Two different loops will be simultaneously controlling both valves till the proces s is stopped or completed. Page | 3 About the company: Using the power of sun as source of energy, Gadhia Solar has implemented some of the world’s largest Solar Thermal Systems in last two decades. Be it industrial, agricultural, institutional or domestic, Gadhia Solar has been a pioneering company with major breakthrough in this area. With extensive experience in installing solar thermal energy systems throughout India and armed with ever improving production facility, Gadhia Solar is the pioneer and market leader in solar thermal energy systems.Gadhia Solar has achieved the ability to develop various applications based on Solar Concentrators like: Solar Cooking Applications o Steam Cooking o Thermic Oil based Cooking, o Direct Cooking, o Small Cookers for Family Solar Power Plants Solar Air-Conditioning Space Heating Systems Process Heat for Various Industrial Applications Large Scale Drinking Water Systems Solar Hot Water of up to 90 0C Solar Incineration Solar Crematoriu m Waste Water Evaporation Solar Desalination Solar Water / Milk Pasteurization Specialized in solar thermal technology for the last two decades, Gadhia Solar is able to provide innovative and cost effective energy solutions for various applications on turnkey basis. Gadhia Solar has a highly focused and dedicated team for research and development in Germany and complimented by a well equipped and automated manufacturing in India. Page | 4 List of Figures Figure 1: Previous Direct Steam Injection Cooking Vessel†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. 14 Figure 2: Steam Jacketed Cooking Vessel. †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. 16 Figure 3: Steam Flow Diagram †¦Ã¢ € ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦.. 17 Figure 4: Logic Diagram for controlling cooking procedure†¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦ 20 Figure 5: Logic Diagram for controlling cooking and Condensate Valve †¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦Ã¢â‚¬ ¦. 21 Page | 5 TABLE OF CONTENTS CHAPTER NO. TITLE ACKNOWLEDGEMENT ABSTRACT SHEET RESPONSE OPTION SHEET ABSTRACT OF PROJECT ABOUT THE COMPANY LIST OF FIGURES PAGE NO. 0 1 2 3 4 5 1. . 2. 1 2. 2 2. 3 2. 4 3 3. 1 4. 5. 5. 1 5. 2 5. 3 6. Introduction Solar Thermal Cooking Scheffler Reflectors. Steam Generation Current P rocedure of Cooking Current Design of Vessel Steam Jacketed Cooking Vessel Designing the vessel. Steam Flow with Diagram Automation Instruments Required Logic Diagram Programming Completed Work and Implementation References 7 9 9 12 13 15 16 16 17 18 18 20 22 23 24 Page | 6 1. Introduction: Gadhia Solar Energy Systems Pvt Ltd. has been making Scheffler reflectors for various purposes. The basic idea that leads to the development of the Scheffler- Reflectors was to make solar cooking as comfortable as possible.At the same time the device should be build in a way that allows it to be constructed in any rural welding workshop after a certain period of training. The locally available materials must be sufficient for the construction of the reflector. The movement started when the first well functioning Scheffler-Reflector (size: 1,1m x 1,5m) was successfully built by Mr. Wolfgang Scheffler in 1986 at a mission-station in North-Kenya. Since then the technology has been continuously impro ved and passed on to many motivated people. This lead to the use of Scheffler reflectors in not just cooking but also other applications like VAM, cold storage, etc. For cooking application, these Scheffler-reflectors are used to generate steam in the header pipe.The water inside the header is heated with the reflector and due to the continuous input of heat; steam at high pressure is generated inside the header. When the outlet of the header is opened, this steam at a higher temperature and pressure is used for cooking. A valve is connected to the steam line which goes to the cooking vessel. When the valve is opened, the steam is let into the vessel and hence the food is cooked with it. Gadhia Solar Energy Systems Pvt Ltd has installed many solar cooking systems in India. They have installed the world’s largest solar parabolic concentrated technology systems at Shri Saibaba Sansthan Trust, Shirdi. This system uses the same Scheffler- reflectors to produce steam from water an d uses that generated steam to cook the food.The solar cooking vessels used currently are being operated manually and needs at least one labor per cooking vessel to operate. The cooking is done by direct injection of steam into the vessel. When the food is cooked by direct injection of steam into the food, as the steam is at high pressure and temperature, it comes out of the vessel. Therefore all of the energy of the steam cannot be utilized for cooking. This increases the heat losses and also increases the cooking time. Also due to the type of vessel, it is not possible to cook different types of food. Risk of contamination is also involved if the water source is not clean. So for this purpose a new design of cooking vessel was proposed.This vessel used the energy of steam to heat the food without coming in contact with it. The Steam Jacketed Cooking Vessel Page | 7 was designed to solve the problems which were faced by the earlier used cooking vessel. In this vessel, the steam was being passed in the jacket around the cooking vessel. As the steam condenses inside the jacket, it transfers its heat energy to the food inside and cooks the food. For the Automation of the cooking process, a Programmable Logic Controller is used which will control the temperature inside the cooking vessel and cook the food accordingly. The temperature inside the vessel will be measured by a RTD (Resistance Temperature Detector).This reading will be processed by the PLC as an Analog Input, and according to the food item selected to be cooked, the PLC will select the cooking temperature and time and start the process on user’s command. The process can be controlled by a START button, STOP button, and food type selection button defining RICE, DAL and VEGETABLE for each button. The operator first needs to select the type of food that has to be cooked. According to the selection, respective LED will turn on which will show the food item selected. Even after selecting an item, th e choice can be changed to another food item. After selection, the START button is required to be pressed which will start the cooking.The cooking algorithm will take care of the temperature and the time required for cooking. If the food gets cooked before the timer gets over, or something goes wrong with the process, the operator can manually shut everything down by pressing STOP button. This cooking vessel will increase the types of food that can be cooked with steam. The automation of the vessel will reduce the need of manual labor and will also cook the food faster at optimum temperatures. Page | 8 2. Solar Thermal Cooking: 2. 1 The Scheffler Reflector: The Idea The basic idea that leads to the development of the Scheffler- Reflectors was to make solar cooking as comfortable as possible.At the same time the device should be build in a way that allows it to be constructed in any rural welding workshop in southern countries after a certain period of training. The locally available materials must be sufficient. The Technology To make cooking simple and comfortable the cooking-place should not have to be moved, even better: it should be inside the house and the concentrating reflector outside in the sun. The best solution was an eccentric, flexible parabolic reflector which rotates around an axis parallel to earth-axis, synchronous with the sun. Additionally the reflector is adjusted to the seasons by flexing it in a simple way. How does this work? The reflector is a small lateral section of a much larger paraboloid. The inclined cut produces the typical elliptical shape of the Scheffler-Reflector.The sunlight that falls onto this section of the paraboloid is reflected sideways to the focus located at some distance of the reflector. The axis of daily rotation is located exactly in north-south-direction, parallel to earth axis and runs through the centre of gravity of the reflector. That way the reflector always maintains its gravitational equilibrium and the m echanical tracking device (clockwork) doesn't need to be driven by much force to rotate it synchronous with the sun. The focus is located on the axis of rotation to prevent it from moving when the reflector rotates. The distance between focus and centre of the reflector depends on the selected parabola. During the day the concentrated light will only rotate around its own centre but not move Page | 9 ideways in any direction. That way the focus stays fixed, which is very useful, as it means the cooking-pot doesn't have to be moved either. In the course of the seasons the incident angle of the solar radiation varies + / – 23. 5 ° in relation with the perpendicular to earth-axis. The paraboloid has to perform the same change of inclination in order to stay directed at the sun. Otherwise it's not possible to obtain a sharp focal point. But the centre of the reflector and the position of the focus are not allowed to move. This is only possible by shaping the reflector after ano ther parabola for each seasonal inclinationangle of the sun, i. e. for each day of the year.This means the reflector has to change its shape. The reflector-frame is build for equinox. By inclining and elastically deforming the reflectorframe all other parabolas can be achieved with sufficient accuracy. Changing the inclination and deforming the reflector are mechanically combined: the two pivots, at each side of the reflector-frame, and a pivot in the centre of the reflector, do not form a line, but the second is located below. That way inclining the reflector leads to a change in its depth, the centre of the reflector is lifted up (big radius of crossbars) or pressed down (small radius of crossbars) relative to the reflector-frame.It's enough to adjust the upper and lower end of the reflector to their correct position to obtain a sufficiently exact reflector-shape. The setting is done by a telescopic bar at each end of the reflector. Adjusting the reflector-shape has to be done man ually every 2-3 days. When all concentrated light enters the opening of the cooking-place installed at the focal point the correct reflectorshape is achieved. After passing the opening the light is redirected by a small reflector (secondary reflector) to the black bottom of the cooking pot. There it is absorbed and transformed into heat. The efficiency for cooking, i. e. heating water from 25 °C to 100 °C, can reach up to 57% and depends on the cleanliness of the eflector-surface and the state of insulation of the cooking-pot. At the focalpoint itself we have measured optical efficiency of up to 75% (with 2mm ordinary glass mirrors). Depending on the season an elliptical reflector of 2,8m x 3. 8m (standard size of 8m? SchefflerReflector) collects the sunlight of a 4,3m? to 6,4m? area, measured perpendicular to the direction of the incident light (aperture). That way the cooking power varies with the season. As an average a 8m? Reflector can bring 22 liters of cold water to boili ng temperature within one hour (with 700W/m? direct solar radiation). Page | 10 There are many options for the design of the cooking-place.Mostly it is integrated into a kitchen building and provides the possibility to use firewood for cooking when the sun doesn't shine. Depending on the type of food which is cooked there is no need for a secondary reflector. This increases the efficiency and simplifies maintenance. Instead of a cooking-place a backing-oven, steam-generator or heat-storage can be installed at the focal-point. Page | 11 2. 2 Steam Generation: With the use of the Schefflor Reflectors, steam at high temperature and pressure can be generated with ease. Steam in saturated temperature can be made available at high pressure by concentrating the focus and heating the water in a closed system with the focused heat. The focus of the reflector has to be concentrated onto a receiver of the header pipe.The receiver is painted black to absorb most of the radiation incident on it. The temperature of the focus of a 16m2 Scheffler Reflector can be as high as 700oC and at the receiver it is around 230oC. At such high temperatures, the water inside the header is being heated. Because of the continuous heat supply from the reflector, the water inside the header gets converted into steam. With time, more steam is being generated and pressure inside the header increases. It is possible to get pressure of 15 barg in around 4 hours using four 12. 5 m2 Scheffler Reflectors under ideal conditions and this steam can be used to cook two batches of 25kg of rice. Page | 12 2. Current procedure of cooking: The current procedure for cooking is by direct injection of steam into the cooking vessel. The food cooked by this procedure consists of mainly rice, dal and some vegetables. All of them are cooked in direct steam. First the outlet valve of the header is opened to a little extent. The drain valve at the vessel is opened to remove the condensate. After every cooking sessio n, there is leftover condensate in the steam line. Since that condensate should not come in contact with food, it needs to be drained out first. After the condensate is removed, the condensate valve is closed and the steam is let into the cooking vessel.The cooking vessel contains a predefined amount of water with the food to be cooked. The steam is passed through the mixture, the temperature increases and the cooking starts. Also the operator needs to stir the mixture at regular intervals. In a 100 liters cooking vessel, it takes almost 15 minutes to cook around 28 kilograms of rice. Since the process involves direct injection of steam, the water used reaches the boiling quickly and the food gets cooked faster. But during cooking, after the water has reached its boiling point, a huge amount of steam goes starts to escape the vessel as the vessel has an open lid. This results into loss of a lot of heat energy which could have been used in cooking the rice quickly.When the food gets cooked, the stand of the vessel has a tilting arrangement with the help of which the operator can take out the food from the vessel. So all the valves are closed and then the vessel is tilted to take the food out. The food is not processed after that, it is collected and served directly. Page | 13 2. 4 Current Design of vessel The current design of the cooking vessel is very effective for direct steam cooking. But for the food items which cannot be cooked by steam directly, it is very difficult for the operator to cook such foods. As mentioned the current design uses a direct injection system. The steam from header is carried by the steam line to the vessel where it is regulated with the help of a ball valve.The construction of the vessel is made to facilitate cooking with the help of steam. The vessel’s bottom dish is a regular torispherical dish and it has a shell of same diameter of that of the bottom dish. There is another plate with a defined curvature above the bottom d ish with small holes in it. This plate is for passing the steam into the cooking material. When food is put into the vessel, some predefined amount of water is added with it. So during cooking process, the water gets heated initially and then the cooking starts. Due to direct injection of steam at temperature greater than 100oC, the water reaches boiling point in a short period of time. Thus the cooking process starts.The operator closes the valve when he thinks that the food is appropriately cooked. Figure 1: Previous Direct Steam Injection Cooking Vessel Page | 14 The present design has some benefits, but there is also another side to it. There are some problems with the current design which cannot be rectified without changing the design. The Advantages and Disadvantages of the present design are listed below. Advantages: 1. It facilitates faster cooking time. 2. Since less material is used in manufacture, it saves manufacturing cost. 3. The design is simple which reduces manufac turing time. 4. As it is lighter, it is easier to transport. Disadvantages: 1. There are substantial heat losses during the cooking process. 2.Since the operators cook in an open lid vessel to keep a watch on the food, lot of steam escapes the vessel resulting decreasing the efficiency of process. 3. If the condensed water in the steam line is contaminated, then there are chances of the food getting contaminated. 4. As the outer shell is not insulated, operator has to be cautious or it could lead to injuries. Page | 15 3. Steam Jacketed Cooking Vessel. 3. 1 Designing the Vessel. The design of the vessel was to be made in such a way that it is easy and economic to manufacture. The material chosen for the pilot project of Steam Jacketed Cooking Vessel was Stainless Steel of the grade 304. This material was chosen as it is not affected by steam and it also resists corrosion. The size of the vessel was chosen to be 100 liters.The dimensions of the inner vessel were taken from the existi ng direct steam injection vessel whose volume was 10 liters. Then according to the pressure calculations, the thickness of the sheet and volume of the jacket was defined. The thickness of the vessel is defined as 4mm and volume of the jacket is approximately 1 cubic m for a pressure of 3 barg inside the jacket of the vessel. The vessel is having 3 openings in the outer shell. Two of them are on the horizontal shell and one is in the bottom of the outer dish end. Out of the three openings, one is used for steam injection, one for a safety valve and the bottom one for removal of condensate.All the openings are of 1 inch diameter and will have pipes welded to it for injection of steam, safety valve and condensate removal. The vessel will have two more openings which will be used to mount the RTD and the temperature gauge to measure the temperature inside the vessel. The final drawing of the vessel is shown in FIG 1. Figure 2: Steam Jacketed Cooking Vessel. Page | 16 4. Steam Flow Diagr ams. Water is supplied to the header tank from an overhead tank. Either the overhead tank is at a greater height than that of header, or a sometimes a small pump is used to pump water into the Header. The Solar Concentrators are focused on the receivers mounted on the header pipe.The receivers are painted black to absorb maximum amount of radiation incident on it. These receivers heat the water inside the header and generate steam at higher pressure. This generated steam is vented to the Steam line and the pressure is controlled by the Pressure regulating valve. The solenoid valve SOV1 controls the steam input into the vessel. Thus the temperature inside the vessel can be controlled by controlling SOV1. As the steam is let inside, it will condense after giving its heat. For removal of this condensate, another solenoid valve has been provided SOV2. This valve will remove the condensate at regular intervals. Figure 3: Steam Flow Diagram Page | 17 5.Automation 5. 1 Instruments required . 1. Programmable Logic Controller: A programmable logic controller (PLC) or programmable controller is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or light fixtures. PLCs are used in many industries and machines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed-up or nonvolatile memory.A PLC is an example of a real time system since output results must be produced in response to input conditions within a limited time, otherwise unintended operation will result. 2. 2-way ON/OFF Solenoid Valve A solenoid valve is an electromechanical valve for use with liquid or gas. The valve is controlled by an electric current through a solenoid: in the case of a two-port valve the flow is switched on or off; in the case of a three-port valve, the outflow is switched between the two outlet ports. For this application, two valves will be used. One will be controlling the steam injection into the jacket. The other valve will be taking care of condensate removal from the jacket. 3. Resistance Temperature Detector.Resistance temperature detectors (RTDs) are sensors used to measure temperature by correlating the resistance of the RTD element with temperature. Most RTD elements consist of a length of fine coiled wire wrapped around a ceramic or glass core. The element is usually quite fragile, so it is often placed inside a sheathed probe to protect it. The RTD element is made from a pure material whose resistance at various temperatures has been documented. The material has a predictable change in resistance as the temperature changes; it is this predictable change that is used to determine temperature. Page | 18 For this application, we will be using a PT-100 RTD with a thermowell.The RTD will be mounted inside the thermowell for its protection from the steam inside the jacket. Thermowell also enables us to change the RTD with ease in case the RTD fails. 4. Pressure Regulator: A pressure regulator is a valve that automatically cuts off the flow of a liquid or gas at a certain pressure. Regulators are used to allow high-pressure fluid supply lines or tanks to be reduced to safe and/or usable pressures for various applications. Since the header pressure is much more than needed for the application, the pressure will be reduced using a Pressure Regulator. The pressure needed for the application is 3 barg while the header can supply pressure 0-15 barg.To have a steady supply of steam and maintain the pressure and temperature, we will be using a pressure regulator. 5. Temperature Gauge with Thermowell: Temperature Gauge is a device that measures temperature or temperature gradient using a variety of different principles. A Temperature gauge has two important elements: the temperature sensor in which some physical change occurs with temperature, plus some means of converting this physical change into a numerical value. A temperature gauge mounted inside a threaded thermowell will be used. Since the temperature reading needed is of the food inside the vessel, the temperature gauge will be mounted on the side of the vessel just like the RTD. The thermowell will protect the Temperature Gauge rom steam inside the jacket of the vessel. Page | 19 5. 2 Logic Diagram: The first diagram displays the logic for controlling cooking process. With turning the device ON, it will start the procedure. According to the outcome of the decision block, it will decide and execute. Figure 4: Logic Diagram for controlling cooking procedure Page | 20 The algorithms given below control the cooking of the food by maintain a specific temperature bracket inside the vessel.  ±3oC range is provided so that the solenoid valves won’t switch ON /OFF at particular temperature which could result in damage. The second logic is for the condensate valve SOV2 which will be ON/OFF at regular intervals.Figure 5: Logic Diagram for controlling cooking and Condensate Valve Page | 21 5. 3 Programming Most of the Programmable Logic Controllers use a different programming language. The language used by them is called Ladder Logic. Ladder logic is a programming language that represents a program by a graphical diagram based on the circuit diagrams of relay logic hardware. It is primarily used to develop software for programmable logic controllers (PLCs) used in industrial control applications. The name is based on the observation that programs in this language resemble ladders, with two vertical rails and a series of horizontal rungs between them.The previously shown logic will be made in Ladder Logic. It will then be downloaded into the flash memory of the Programmable Logic Controller. The PLC will execute the logic and accordingly it will monitor and process the parameters involved. In this project, the opening and closing of both valves and will be monitoring the temperature during the process. The program is made on proprietary software which is supplied by the vendor of the PLC. Every PLC make has specific software which is used to build the program and download the program into the PLC. It can also be used to change the process parameters in online mode. The software also provides offline simulation of the process.For data logging purposes, usually different software is used. The Ladder Logic for the project is under construction and will be finished by the time procurement of all the instruments is done. The parameters which need to be used in the logic will be found out during the processing of the procurement of instruments. During the period of procurement, the manufacturing of the vessel and designing the ladder logic will be done. Page | 22 6. Completed Work and Implementation: From the start, the proj ect has been progressed according to the timeline. Now, all the instruments and material needed for the project has been indented and is in process. Some of the instruments have been dispatched.But for procuring the entire indent, it is going to take some more time. Meanwhile, since the Logic is available, the ladder program is being made and is approaching completion. Also, the manufacturing of vessel is in process and the vessel will be ready by the end of next week. After program is completed, some more time will be given to test it in offline mode and debug the program is any bugs are found. After all the materials are processed and the final values for the process parameters are found out, the project will enter the implementation and testing phase. The entire infrastructure needed for the cooking vessel and the instruments will be constructed on the site.For different types of foods, the values initially found out of temperature and time will be used. If the parameters are not off by some amount, they will be rectified and the control will be made as efficient as possible. During the implementation, various temperature and time readings will be taken. For every type of food item, a detailed sheet should be made which will have all the parameters. According to the observed readings, new and better parameters will be decided which should reduce the cooking time and also increase the efficiency. Page | 23 References: The Scheffler – reflector http://www. solare-bruecke. org/ www. en. wikipedia. com http://www. spiraxsarco. com/resources/resources. asp www. mnre. gov. in Page | 24
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