                    11 12 P&ID: Tutorial 1 Name: Matric No. Group: P&ID: Tutorial 1 Write approprite names in the respective blank lines of the following P&ID based on ISA-5.1(1984).      product  Feed    TT TC Fuel      I/P FC TC  SP       FT 11 12 11 ASD 12 © Abdul Aziz Ishak, Universiti Teknologi MARA Malaysia (2009)

Draw appropriate P&ID in the respective boxes based on ISA-5.1(1984). Name: Matric No. Group: P&ID: Tutorial 1 Draw appropriate P&ID in the respective boxes based on ISA-5.1(1984).  Pressure control for vapor product line.  Flow control for steam supply line.  Level control for liquid level in vessel. Steam supply Ref: 5-2.2

 Pressure safety valve for vessel. Name: Matric No. Group: P&ID: Tutorial 1 Draw appropriate P&ID of a kettle reboiler in the respective boxes based on ISA-5.1(1984).  Pressure safety valve for vessel.  Pressure and temperature gauges for reboiler vapor line.  Pressure control for steam line. In this reboiler type, steam flows through the tube bundle and exits as condensate. The liquid from the bottom of the tower, commonly called the bottoms, flows through the shell side. There is a retaining wall or overflow weir separating the tube bundle from the reboiler section where the residual reboiled liquid (called the bottoms product) is withdrawn, so that the tube bundle is kept covered with liquid.  Liquid level switch to manipulate a solenoid valve for bottom products .

Install a secondary overpressure device (PRV) at point C. Name: Matric No. Group: P&ID: Tutorial 1 Draw appropriate P&ID of a kettle reboiler in the respective boxes based on ISA-5.1(1984). Install a differential pressure transmitter (dPT) between point A and B. Transmit this signal to a DCS. Inside the DCS, show this reading (dPIR). Install a DCS differential pressure alarm high (dPAH). When alarm high is triggered, shut dirty air inlet using a solenoid valve (PS to solenoid valve). Install a secondary overpressure device (PRV) at point C. In reverse pulse baghouses, individual bags are supported by a metal cage, which is fastened onto a cell plate at the top of the baghouse. Dirty gas enters from the bottom of the baghouse and flows from outside to inside the bags. The metal cage prevents collapse of the bag. Bags are cleaned by a short burst of compressed air injected through a common manifold over a row of bags. The compressed air is accelerated by a venturi nozzle mounted at the Reverse-Jet Baghouse top of the bag. Since the duration of the compressed-air burst is short (0.1s), it acts as a rapidly moving air bubble, traveling through the entire length of the bag and causing the bag surfaces to flex. This flexing of the bags breaks the dust cake, and the dislodged dust falls into a storage hopper below. www.hvacqld.com/pages/library.asp A B C

Propose a suitable control system for the following system. P&ID: Tutorial 1 Propose a suitable control system for the following system. The fuel assemblies which form the reactor core, are loaded into a specially fabricated cylindrical steel pressure vessel (the reactor pressure vessel). The reactor pressure vessel is about 12 metres high and has a 20 cm thick steel wall with an inner diameter of about 4 metres. It weighs about 314 tonnes. The primary coolant system of a 900 MW class reactor consists of the reactor pressure vessel and the primary circuit with 3 identical loop (Top figure). Each loop has a primary coolant pump, a steam generator and the interconnected piping. A pressuriser is installed in one of the 3 loops. Each primary coolant pump will circulate the cooling water (ordinary water) around the loop through the reactor core at a high pressure of about 155 bar (1 bar = 100 kPa). In addition to its moderator function, the cooling water would also transfer the heat from the reactor core to the steam generator. The water temperature at the reactor pressure vessel outlet is about 330 degree C whereas the water temperature at the inlet of the vessel is about 290 degree C. The cooling water is in a sub-cooled condition at such high temperature and pressure to prevent it from boiling. The steam generator of about 20 metres in height is fitted with U tubes in the inside which serve as the heat exchanger to transfer the heat from the water in primary circuit to that in the secondary circuit. The heat will convert the feed water in the secondary circuit to steam for driving the turbine-generator (Right figure). Primary Coolant Circuit The pressuriser is mainly used to maintain the pressure in the primary coolant circuit and prevent overpressure. It is a cylindrical pressure vessel of about 2 m in diameter and about 13 m long, tapping off from one of the hot legs in the primary loops. The steam and water volumes occupy the top half and bottom half of the pressuriser respectively during normal operation. There are water spray nozzles at the top and a group of heaters at the bottom of the pressuriser. The water level inside the pressuriser and thus the pressure in the primary coolant circuit can be controlled by operation of the heaters and water spray. A sophisticated pressuriser level control system is used to regulate the water level inside the pressuriser so as to ensure a proper pressure control during reactor power change and transient plant operation. The heaters will be turned on to increase steam production if the pressure drops. If the pressure increases, the water spray will be turned on to condense the steam to reduce the pressure. In addition, the control system will provide a protection signal to shutdown the reactor automatically if the pressure inside the pressuriser is too high or too low. At the first start up of a new reactor, primary source rods consisted of californium-252 are inserted into the reactor to produce sufficient neutrons to initiate the first fission. Secondary source rods consisted of antimony and beryllium are also inserted at the same time to provide a regenerative neutron source such that it will initiate nuclear fission in subsequent start up of the reactor throughout its service life. To ensure nuclear safety and allow control of the fission rate inside the reactor, some fuel assemblies are fitted with control rods. Each control rod assembly consists of a number of absorber rods attached to a spider assembly and coupled to the control rod drive mechanism. The absorber rods are made up of neutron absorbers such as silver, indium and cadmium. Hence, by adjusting the position of the control rods, the number of neutrons and thus the fission rate in the reactor can be controlled. The control rod assemblies are fitted with driving mechanism to move the control rods up and down in the reactor core for controlling the start up of the reactor, adjusting its power output, and enable the normal shutdown of the reactor and scram. In addition, the fission rate in the PWR can also be controlled by adjusting the boron (a neutron absorber) concentration in the primary coolant circuit. After start up of the reactor and attaining its desired power output, it would be maintained at criticality for stable operation at power. The reactor can be shutdown during emergency by cutting off the power supply to the control rod driving mechanism which then causes the control rods to drop down to the reactor core by gravity quickly and thereby stopping the nuclear fission immediately. Open-ended question http://www.hko.gov.hk/education/dbcp/pow_stat/eng/r7.htm