Plantilla de excel para aplicar la metodología HazopDescripción completa
Sample of a HAZOPFull description
hazop silDescripción completa
hazopFull description
Study Node: Oxidation Reactor Process : Oxidation of p-xylene to Terephthalic Acid
Description complète
A heat exchanger is used to heat flammable, volatile solvent, as shown in FIGURE Q1. Q1 . The temperature of the outlet stream is measured by a thermocouple, and a controller valve manipulates the amount of steam to the heat exchanger to achieve the desired set point temperature. Construct a HAZOP study on the intention of “flow of hot solvent from
heat exchanger” using guidewords NO, NO, LESS, LESS, MORE, MORE, AS WELL AS and REVERSE. REVERSE. Propose only TWO (2) (2) possible causes, consequences and actions for each of the guidewords. [15 marks]
Steam
Control Valve TRC Volatile Solvent
Heat Exchanger
Condensate
FIGURE Q1: Volatile solvent heating system
Internal
PROJECT TITLE STUDY NODE STUDY NODE No 1
Thermocouple at Outlet Stream
2
Heat Exchanger System
Internal
HAZARD AND OPERABILITY STUDY REPORT FLOW OF HOT SOLVENT IN HEAT EXCHANGER DATE 26/11/2016 1 PROCESS HEATING OF FLAMMABLE, VOLATILE SOLVENT PARAMETER GUIDE DEVIATION CAUSES CONSEQUENCES ACTIONS WORD Temperature LESS LOWER 1. Malfunction 1)Flow of 1) Install low TEMPERATURE of solvent from temperature thermocouple heat exchanger alarm 2. Lower than below desired 2)Regular the temperature maintenance acceptable 2)Loss of and thermocouple material as inspection of temperature desired product the range are not achived. temperature controller MORE HIGHER 1. Malfunction 1)Flow of 1) Install TEMPERATURE of solvent from relief valve thermocouple heat exchanger 2) Install 2. Too high to above desired high be detected temperature temperature by 2) Overpressure alarm thermocouple occur as more temperature solvent change range to vapor. Flow NO NO FLOW 1. The inlet 1) no flow of 1) Install valve failed to hot solvent flow alarm open from heat system and (malfunction) exchanger indicator 2. The inlet 2) Damage the 2) Regular solvent is heat exchanger. inspection insufficient and maintenance of the piping system and control valve REVERSE REVERSE 1. The inlet 1) No flow of 1) Install FLOW solvent has hot solvent pressure low pressure from heat indicator 2. Failure of exchanger 2) Install inlet solvent 2) Heat check valve source exchanger resulting overheated backward flow Pressure LESS LOW 1. Control valve 1)Reverse Flow 1) Install PRESSURE failure. 2)Loss of solvent pressure 2. Leakage in indicator
pipe
3
Controller Valve of Steam Line
Internal
Flow
MORE
HIGH PRESSURE
1. Excessive flow from inlet streams. 2. Control valve failure.
LESS
LOW FLOW
1. Failure of receiving signal from thermocouple 2. Control valve failure
MORE
HIGH FLOW
1. Control valve failure 2. Inlet steam overheated causes high pressure and overflow
2) Install check valve
1) Explosion 2)Solvent from heat exchanger does not reach desired temperature 1)Solvent from heat exchanger below desired temperature 2) Pressure drop in heat exchanger.
1) Explosion 2) Rupture of heat exchanger due to overpressure
1) Install pressure indicator 2) Install relief valve 1) Install flow alarm with minimum flowrate 2. Regular inspection and maintenance of piping system and control valve 1) Install flow alarm with maximum flowrate 2. Regular inspection and maintenance of piping system and control valve
