Crude Preheat Curramix Coating on Both OD & ID 1-Year Projection

Repeat of Study 1, but it assumes anti-fouling coating on both tube OD & ID.

This study evaluates a Crude preheat exchanger service heat transfer performance with the following tube material and coatings and estimates the energy savings and CO2 Emissions Reduction:

• Carbon Steel
• Stainless Steel
• Carbon Steel Tube ID & OD Coated
• Stainless Steel Tube ID & OD Coated

• Service – Desalted Crude vs Resid
• Tube ID Coating Thickness – 25 Microns (0.001 inch)
• Tube OD Coating Thickness – 25 Microns (0.001 inch)
• Coating Thermal Conductivity – 0.722 Btu/hr-ft-F
• Fuel Value -$3.50 per MBtu/hr
  [Note fuel prices in Asia can be 3X compared to US]
• Furnace Efficiency = 0.9
• Network Factor = 0.85
  [Part of the Duty Gain in the Exchanger Diminishes Heat Transfer on other Exchangers in the Preheat Train due to changes in temperature differentials]
• CO2 Reduction based on EPA Conversion Equations
• Heat Transfer Calculation performed with HTRI XIST
• Assumed Fouling Factor shown in the Comparison Tables below
• All bundles are cleaned yearly
• Assumed Inlet Operating
  • Crude Inlet Temp – 400 F
  • Crude Rate – 1800 klb/hr
  • Resid Inlet Temp - 600 F
  • Resid Rate – 1,082 klb/hr

Heat Exchanger Geometry

• TEMA – AES
• Shell Id = 54”
• 1130 Tubes
• 1” Tube OD
• 0.083” tube wall thickness
• 2 Tube Passes
• 20 ft length
• 11 Baffle Cross Passes, Single Vert Seg , 18.8% Cut

Comparison Tables

Coated Versus Carbon Steel

• Annualized Duty Reduction = 14 MBtu/hr
• Energy benefit = $405k a year
• CO2 Equivalent Benefit = 6,131 Tons over 2 years

Coated Versus Stainless Steel

• Annualized Duty Reduction = 9 MBtu/hr
• Energy benefit = $260k a year
• CO2 Equivalent Increase Emissions = 3,937 Tons a year