Please Need Help ASAP Tess aper play online uonline.blackboard.com/bbcswebdav/pi
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Tess aper play online uonline.blackboard.com/bbcswebdav/pid-2579698-dit-content-rid-19607847 1/courses/ELEN 4304 45F-1 2017 PARENT/Spring%202017.pdf Flip Diving A free n this process, maple syrup is heated as it passes through a steam heat exchanger, then enters an evaporator where the water boils off. The purpose of this is to raise the sugar concentration of the syrup, making it suitable for use as a food topping. A level control system (LT, LIC and LV) maintains constant syrup level inside the evaporator, while an analytical control system CAT, AIR, AC, and AV monitors the sugar concentration of the syrup and adjusts steam flow to the heat exchanger accordingly. Suppose a process operator accidently leaves the manual block valve locked and tagged shut following an overhaul of the process, so that no steam can enter the heat exchanger. Describe how both control syst respond over time to this process condition. Steam supply Vapor compressor Water vapor ou Evaporator AV LT LIC Heat exchange Concentrated syrup out Condensate eturn to boiler AT Liquid pump Syrup in FT AIR ACExplanation / Answer
a) A heat exchanger is a device that allows heat from a fluid (a liquid or a gas) to pass to a second fluid (another liquid or gas) without the two fluids having to mix together or come into direct contact. The essential principle of a heat exchanger is that it transfers the heat without transferring the fluid that carries the heat.
A hot fluid flows through a tube coiled inside a larger shell through which another, colder fluid is running in the opposite direction. Heat is exchanged by the fluids: the hot fluid cools down and the cold fluid warms up, without them actually coming into contact and mixing.
b) It is important to monitor or control the level of syrup inside the evaporator because When maple sap boils vigorously it creates quite a bit of foam, which will overflow the evaporator. and one cannot completely eliminate the foam because if it is completely eliminated then the water takes more time to boil.
c)
Lockout/tagout" refers to specific practices and procedures to safeguard employees from the unexpected energization or startup of machinery and equipment, or the release of hazardous energy during service or maintenance activities.1 This requires, in part, that a designated inpidual turns off and disconnects the machinery or equipment from its energy source(s) before performing service or maintenance and that the authorized employee(s) either lock or tag the energy-isolating device(s) to prevent the release of hazardous energy and take steps to verify that the energy has been isolated effectively. If the potential exists for the release of hazardous stored energy or for the reaccumulation of stored energy to a hazardous level, the employer must ensure that the employee(s) take steps to prevent injury that may result from the release of the stored energy.
Lockout devices hold energy-isolation devices in a safe or"off" position. They provide protection by preventing machines or equipment from becoming energized because they are positive restraints that no one can remove without a key or other unlocking mechanism, or through extraordinary means, such as bolt cutters. Tagout devices, by contrast, are prominent warning devices that an authorized employee fastens to energy-isolating devices to warn employees not to reenergize the machine while he or she services or maintains it. Tagout devices are easier to remove and, by themselves, provide employees with less protection than do lockout devices.
Employees can be seriously or fatally injured if machinery they service or maintain unexpectedly energizes, starts up, or releases stored energy.