Expander in a cryogenic air separation plant Essay

Expander in a cryogenic air separation plant - Essay Example Ameen argues that â€Å"expanders are used to expand various gases efficiently from high to low pressures to obtain refrigeration† (Ameen 2006 p. 142). Jumonville asserts that in spite of variations in specific processes, â€Å"almost all turboexpanders are used to remove energy from a gas stream, thereby producing power and cooling the gas† (Jumonville 2010 p. 148). In the process of expanding high pressure gas across the turbine, the extraction of most of the gas’s energy potential occurs (Gopalakrishnan & Hardeveld n.d; Mokhatab & Poe 2012). The energy extracted is then transmitted to the shaft and the compressor (Bloch 2006). Consequently, an enormous reduction of pressure in the gas occurs. This consequential fall in pressure together with efficient energy extraction creates refrigeration, which is essential for cryogenic processing of gas (Sapali 2009). Therefore, the use of expanders in a cryogenic plant is to expand high pressure gas thereby leading to te mperature fall. This decline in temperature results into refrigeration, which is essential for liquefaction of gases in a cryogenic plant (Finley 2013; Mokhatab & Poe 2012). Jumonville (2010) argues that â€Å"in most applications, the turboexpander normally runs faster and operates with colder temperatures than any other equipment in the plant† (Jumonville 2010 p.147). The turbine Expanders converts the cryogenic fluid stream hydraulic energy into electric energy (Habets & Kimmel 1999). The expander used in a cryogenic plant is usually associated with numerous benefits. The use expanders in cryogenic plants ensures optimum efficiency, reduces operation cost and also offer reliable and strength augmentation (Kerry 2010). The cryogenic turbine expanders’ efficiency (thermodynamic efficiency) can be observed by obtaining the difference in enthalpy at the inlet and the exit. For an upward flow expander, the pressure of the fluid is reduced continuously from

Rehabilitation of the Injured Athlete Essay Example | Topics and Well Written Essays - 2000 words

Rehabilitation of the Injured Athlete - Essay Example The program will encompass total recovery, involving pre-habilitation and the actual rehabilitation process – including targeted treatment and exercises, aimed at returning Simon to his rugby team and game as soon as possible. The shoulder consists of three bones the clavicle, scapula, and humerus, and two joints, the acromioclavicular and glenohumeral joints (Quinn, 2006). The bones are connected to each other by ligaments, while they are connected to muscles by tendons (Quinn, 2006). These structures, along with the rotator cuff muscles, cooperate to provide motion, mobility, and strength to the very movable shoulder joint which is quite unstable and prone to injury from impact (Quinn, 2006). Nevertheless, the 13 muscles in the shoulder joint, offer biomechanical protection which provides a measure of stability to this vulnerable and unstable joint (Funk, 2011). Simon’s collision caused his dislocated shoulder joint, where an extreme rotation occurred violently twisti ng his shoulder upward and backward, causing the humerus to jump out of the glenoid, and delivering intense pain and weakness in the arm, presumably because the rotator cuff was damaged during the impact (Cunha, 2011). The four tendons in the rotator cuff are connected to four muscles which turn the arm inward, upward, and outward (Cunha, 2011), and are responsible for stabilizing the humerus in the socket (Erstad, 2010). Simon’s collision caused the joint capsule, cartilage, and rotator cuff ligaments, which keep the shoulder intact, to tear (Wedro, 2011). The resultant pain signalled the need for medical attention. The injured shoulder would first have been tied in a makeshift sling, before Simon was rushed to a doctor (Cunha, 2011) (Mayo Clinic Staff, 2009). Most likely he was given pain killers and then quickly examined by the doctor, who probably touched the shoulder from the side to see whether the humeral head was in position (Cunha, 2011). Simon probably grimaced at t he pain in the front of the shoulder, caused when the doctor bent his elbow or turned his wrist, indicating a SLAP lesion (Pesic, 2011). The doctor would then x-ray the injury to confirm the diagnosis and ascertain whether there were broken bones (Cunha, 2011). Having found no broken bones, the doctor would first determine whether the SLAP lesion could be treated non-surgically through shoulder rest and medication to lessen inflammation (Pesic, 2011). Simon would naturally be removed from active play (Pesic, 2011). SLAP lesion physical therapy would be done by stretching and strengthening the muscles surrounding the rotator cuff and scapula, through special exercises (Pesic, 2011). Cold therapy, which can be a three-hour application of ice packs or a massage, could also be done to reduce swelling and pain (Pesic, 2011). The RICE technique of rest, ice, compression, and elevation of the shoulder would also be applied (â€Å"Cold Therapy,† 2011). If those measures are not succe ssful, surgery would be scheduled. Maunder (2011) feels that Simon should be prepared mentally and physically for surgery to increase his chances of success. Prehabilitation would give him an opportunity to ask questions and learn