High Heat Density Applications of Next Generation Ultra Low NO X Burners Shell Martinez Refinery Callidus CUBL Burners Galen Coupe Shell Global Solutions Kurt Kraus - Callidus Technologies
F-53 Low NOX Burner Retrofit Project: Retrofit 1965 era Born Natural Draft Heater to meet corporate consent decree requirements and local air board regulations. Project Goal NOx 0.045 #/MMBtu-HHV Actual, in-field NOx: 0.026 #/MMBtu-HHV Key Project parameter Common Plenum retrofit burner inserts, no major floor or plenum modifications. 2
F-53 Low NOX Burner Retrofit Service: All radiant heater for Catalytic Reformer Reactor Regeneration Loop. Heater Type Burner Model Number of Burners Burner Tile Outside Diameter Heat Release Per Burner Total Heat Release Burner Circle Tube Circle Radiant Height Vertical Cylindrical CUBL-8P 3 23.75 Inches 8 MMBtu/hr 24 MMBtu/hr 37 Inches 124 Inches 24 Feet 3
F-53 Flue Gas Outlet Duct (No Convection Section) 4
F-53 Low NOX Burner Retrofit Problem: After retrofit, heater firing rate was limited due to limit on max. flue gas outlet temperature. Temperature Limit: 1650 F BWT Firing Rate Limit: 18.5 MMBtu/hr LHV Firing Rate Needed: 22.5 MMBtu/hr LHV 5
F-53 Low NOX Burner Retrofit Evaluated Impact of other Process Changes (Compressors, Exchangers, Dryers etc.) Looked at identical burners in a different heater (F-66). Looked OK compared to older generation Low NOX burners, but too long for a CUBL. Observed long flames running up center of heater. Checked: O2, Gas Pressure Firing Rate, Fuel Heating Value Verified Heater is Sealed 6
F-53 Call (Blame) the Burner Guys Verify Design Parameters Heat Flux & Heat Density Conformance to API Burner to Tube Spacing Tight on Burner to Burner Spacing Computational Fluid Dynamics (CFD) Model 7
Design Verification: Heat Density The duty per unit area contained within the tubes is the Area Heat Density heat area Qin / < 300,000 Btu/SF xy Volumetric Heat Density heat vol Qin / xyz x z < 30,000 Btu/CF y 8
F-53 Floor Layout (3 CUBL BURNERS) HEATER CASING Ø23 4 3 " BURNER TILE 8" Ø37" BC Ø124" TC FUEL GAS TIP 9
F-53 Heat Density Calculations Burner Model Number of Burners Burner Diameter Heat Release Per Burner Total Heat Release Burner Circle Tube Circle Floor Area Area Heat Density Radiant Height Radiant Volume Volumetric Heat Density CUBL-8P 3 23.75 8 24 37 124 83.9 286,000 24 2,013 12,000 Inches MMBtu/hr MMBtu/hr Inches Inches Sq. Feet Btu/Ft 2 Feet Ft 3 Btu/ Ft 3 10
F-53 Design Verification API 560, Table 12 Minimum Clearance for Natural Draft Operation Allowed Clearance Actual Clearance Maximum Heat Release Per Burner 8 8 Vertical to Centerline Roof Tubes or Refractory (Feet) 20.75 25 Meets API! Horizontal to Centerline Wall Tubes from Burner Centerline (Feet) 3.5 3.625 11
F-53 Floor Layout (3 CUBL BURNERS) HEATER CASING Ø23 4 3 " BURNER TILE 8" Ø37" BC Ø124" TC FUEL GAS TIP 12
Heater Floor Layout (3 CUBL BURNERS) HEATER CASING Ø23 3 4 " BURNER TILE 8" Ø37" BC Ø124" TC FUEL GAS TIP 13
F-53 Heat Density Calculations Total Heat Release Burner Circle Tube Circle Floor Area Area Heat Density 24 37 124 83.9 286,000 MMBtu/hr Inches Inches Sq. Feet Btu/SF Area Heat Density Inside B.C. 1,270,000 Btu/SF 14
F-53 Floor Layout (3 CUBL BURNERS) HEATER CASING Ø23 3 4 " BURNER TILE 8" Ø37" BC Ø124" TC FUEL GAS TIP 15
F-53 Floor Layout (3 CUBL BURNERS) HEATER CASING Ø23 3 4 " BURNER TILE 8" Ø37" BC Ø124" TC FUEL GAS TIP 16
F-53 Heat Density Calculations Total Heat Release Burner Circle Tube Circle Floor Area Area Heat Density 24 37 124 83.9 286,000 MMBtu/hr Inches Inches Sq. Feet Btu/SF Before: Area Heat Density Inside B.C. 1,270,000 Btu/SF After: Area Heat Density Inside B.C. Nearly 60% Reduction 800,000 Btu/SF 17
CUBL Burner CFD Similar Problem At a Different Facility Before Plugging Tips Twelve Burners in This Heater Large Project Justified CFD Three Burner Clusters Iso-surfaces of 6.6% O2 (Wet), Scale El. In Feet 18
CUBL Burner CFD Similar Problem At a Different Facility After Plugging Tips Twelve Burners in This Heater Large Project Justified CFD Three Burner Clusters Iso-surfaces of 6.6% O2 (Wet), Scale El. In Feet 19
F-53 Solution: Plug Three Tips Increased firing rate from 18.5 MMBtu/hr LHV to 22.5 MMBtu/hr LHV Now Operating at original capacity with lower flue gas outlet temperature (1620F) with no negative impact on NOx (0.026 #/MMBtu-HHV ) 20
F-53 Solution: Plug Three Tips Heater no longer system bottle neck. Flame observed to be much shorter and distinct. 21
Approaches to High Heat Density Heaters Upfront Computational Fluid Dynamics Optimize Burner Circle Fewer Larger Burners 22
High Heat Density Applications of Next Generation Ultra Low NOX Burners Shell Martinez Refinery Callidus CUBL Burners Questions