Start up XXX from normal shutdown Introduction

Transcription

1 Start up XXX from normal shutdown Introduction This procedure describes how to start a XXX after it has been shutdown normally, meaning there is a liquid and gas inventory in the unit. Task Criticality = High This task has been rated as high criticality because: A large inventory of hazardous material will be present and/or introduced when the task is performed; Lighting heaters and switching HV electrical items constitute a potential source of ignition; There will be multiple and complex changes of configuration of plant and equipment; Safety systems need to be defeated during the task. Key precautions The following have been identified as key risk controls: Low pressure trip override used to start hot oil system must be removed once hot oil circulation has been established; A compressor must be started once cold circulation has been achieved to control pressures in the unit; Unit must be warmed up slowly, in a controlled manner to avoid trips; If XXX is started too late or too slowly, gas processing may trip due to high levels; Route from separator D1401 to storage tank T3205 must be opened to prevent high interface/level trips. Accompanying documents The following procedures for high criticality tasks must be referred to during this task:.

2 Task overview 1. Make train available on ESD system Select "Emergency condensate" route from DCS Reset XXX from ESD panel Press "master operate" from ESD panel Select route from DCS Reset compressor by pressing "start" button on DCS 2. Confirm XXX is lined out for processing Confirm train inlet block valve is open Confirm block valve in line from separator (D1401) is open level control valve is open separator pressure feed drum (D1401) pressure control valve is open LP recycle pressure IP recycle pressure Confirm block valve at exit to IP after cooler is open Confirm control valves are set to P&ID settings Confirm fuel gas valve to feed drum is open 3. Establish hot oil circulation Override low pressure trip Start hot oil pump Once hot oil circulation has been established remove low pressure override 4. Start cold circulation Start a semistabilised condensate pump Open feed drum inlet Open feed drum inlet control valve to establish a flow 5. Start a compressor 6. Bring XXX up to operating temperature Start a hot oil heater Slowly open reboiler temperature control valve to introduce hot oil onto reboiler 7. When unit conditions steady, route through unit to storage tank T1601 Open route to unit Close unit bypass route Swap over outlet to tank T1601

3 Pre-start checks Check 1 XXX was shutdown in controlled manner leaving liquid and gas inventory 2 A compressor is available 3 All utilities are available 4 Storage tank T1603 is available with level above 2.5m Initial Pre-start checks have been completed and the XXX is ready to be started

4 Procedure 1 Make XXX available on ESD system 1.1 Select "Emergency condensate" route from DCS 1.2 Reset Stream 1 from ESD panel 1.3 Press "master operate" from ESD panel 1.4 Select " condensate" route from DCS 1.5 Reset compressor by pressing "start" button on DCS 2 Confirm XXX is lined out for processing 2.1 Confirm train inlet block valve is open V0215 (next to YSV1416) 2.2 Confirm block valve in line from separator (D1401) is open V14038 (next to YSV1407) 2.3 Confirm block valve on level V14026 (next to LCV1417) 2.4 Confirm block valve on separator pressure V14035 (next PCV1429) 2.5 Confirm block valve on feed drum (D1401) pressure control valve is open V14051 (next to PCV1412) 2.6 Confirm block valve on LP pressure V23037 (next to PCV23015) 2.7 Confirm block valve on IP recycle pressure V23059 (next to PCV23025) 2.8 Confirm block valve at exit to IP after cooler is open V Confirm control valves are set to P&ID settings 2.10 Confirm fuel gas valve to feed drum is open XXXX XXX is available on ESD system and has been lined out for processing condensate

5 3 Establish hot oil circulation 3.1 Override low pressure trip PALL Start hot oil pump P2401 A/B 3.3 Once hot oil circulation has been established remove low pressure override PALL2433 Hot oil circulation has been established The low pressure override has been removed 4 Start cold circulation 4.1 Start a circulation pump P1603 A/B 4.2 Open feed drum inlet valve YSV Open feed drum inlet control valve to establish a flow FCV Start a compressor Initial 6 Bring XXX up to operating temperature 6.1 Start a hot oil heater 6.2 Slowly open temperature control valve to introduce hot oil onto reboiler TCV When happy that unit conditions are steady, route through unit to storage tank T Open route to unit 8.2 Close unit bypass route 8.3 Swap over outlet to storage tank T1601 The XXX has been successfully restarted