Safety
Hot Drums
1) Remote Drilling
Sound monitoring top and bottom
Cameras
Remote digital control from a Control Room
Sensor to determine slack cable
2) Remote Unheading
Minimize risk of boil-over
Drain drum before opening top head
Open top head before opening bottom head
3) Interlock System
Have a total interlocking system of MOV valves with both top and bottom heads.
Operations
- Banana effect
- Liquid in bypass line
- Switch midpoint how long
- On-line spalling medium temperature
- Quench steam rates
- Foaming
Blowdown
Early drum
- Sludge injection
- Double quench
- Auto-shift cutting tool
- Remote cutting/unheading
- Automation
Getting humans off the structure
Increased level of process control sophistication
- More training
Maintenance / Reliability
- Drill Stems Operation Cutting Tools
- Bending Stem
Maint issues: Leakage/Break
- Monitoring: Drill Positioner
Procedures
Case Study discussed that show reduction in maint costs
Water Filtration/Quality
Problem: Large fines causing maint issues in bits and pumps
Increase filtration
Increase frequency of cleaning holding tanks
Bulging/Cracking/Deformation (leaning)
Assessing
Laserscan Where and Is it Growing
Thermal Gradient: Health Monitor System to measure process to minimize damage during operation
Leaning
Side inlet causing preference to oneside of drum
Process
- Control the heater outlet to get a drum inlet temperature of about 900F.
Lower temperatures cause sandy coke, which leads to hot spots and blowouts
- Some locations ramp their heater outlet for the last 4 hours to help reduce the potential for hot spots ramp 7 deg F at the end of the fill
- Need to monitor the drum OVHD temperature before the quench to help prevent sandy coke.
- Raising heater outlet temperature helps the coke morphology reduces sandy coke (hot spots)
- There can be crude type mismatches that can cause sandy or dusty coke. May need to limit the crude differences to coke avoid problems with hot spots
