Porter McGuffie, Inc. Engineering Measurement and Analysis Services Examining the Cost Return Ratio for CFD in the Gas, Oil and Chemical Industries Mike Porter, P.E Principal Engineer Porter McGuffie, Inc. 544 Columbia Dr., Lawrence, KS 66049 www.pm-engr.com
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Tail Gas Unit 512,000 lb/hr 85’ long 20’ ID
Porter McGuffie, Inc. Engineering Measurement and Analysis Services The initial goal: Reduce pressure drop − Driven by low available fan power Evaluate two different inlet piping geometries
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Inlet piping system pressure magnitudes
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Surface plot of Y-velocities above bed
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Streamlines colored by velocity
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Inlet piping system pressure magnitudes
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Streamlines colored by velocity
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Surface plot of Z-velocities above bed
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Savings? 1.5” w.c. reduced pressure drop Catalyst life – 4-8 years − 8,000 ft 3 catalyst − $400/ft 3 catalyst cost
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Feed water heat exchanger Plan 3 Plane 1 Plane 2
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Velocity Magnitudes on Cut Plane 1
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Inlet Modifications Additional Extraction Steam Nozzle
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Near Inlet Modifications Increased Impingement Plate Size Additional Tube Support Plate Additional Tube Support Plate
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Velocity Magnitudes on Cut Plane 1
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Savings? Vessel life – 30 vs 15 years Capacity increase – 15%
Porter McGuffie, Inc. Engineering Measurement and Analysis Services SRU Boiler
Porter McGuffie, Inc. Engineering Measurement and Analysis Services The Problem:
Porter McGuffie, Inc. Engineering Measurement and Analysis Services
Porter McGuffie, Inc. Engineering Measurement and Analysis Services
Porter McGuffie, Inc. Engineering Measurement and Analysis Services When that happens:
Porter McGuffie, Inc. Engineering Measurement and Analysis Services The variables: Heat Flux Superheat Void fraction
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Water Side Model– 4.3 Million Cells
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Volume Fraction of Steam at time = 25 seconds
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Volume Fraction of Steam at time = 28 seconds
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Upper Tubes Showing Steam Void > 0.9
Porter McGuffie, Inc. Engineering Measurement and Analysis Services External Tube Temperature
Porter McGuffie, Inc. Engineering Measurement and Analysis Services SRU Data vs. Peak Heat Flux Curve 120000 Flux Curve Point 1 Point 2 100000 Point 3 Point 4 Point 5 80000 Flux (BTU/hr*ft^2) 60000 40000 20000 0 0 20 40 60 80 100 120 140 160 180 200 Superheat Temperature (F)
Porter McGuffie, Inc. Engineering Measurement and Analysis Services The heat flux is proportional to the Mass Flow Rate and the Dynamic Viscosity − Unfortunately, the Dynamic Viscosity is not a process parameter If the parameters are plotted and curve fit, for a particular geometry, it is possible to relate the heat flux to the mass flow rate and the process temperature. − These are measured process parameters This allows the development of a simple graph to control the process
Porter McGuffie, Inc. Engineering Measurement and Analysis Services
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Savings? SRU repair cost – less than analysis Plant throughput reduction – less than analysis – per hour
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Baghouse flow analysis
Porter McGuffie, Inc. Engineering Measurement and Analysis Services
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Velocity Pressure
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Location % Difference from Mean 1 3.55% 2 .090% 3 -1.35% 4 -4.68% 5 -3.65% 6 -6.68% 7 -3.90% 8 -6.44% 9 -3.65% 10 -7.43% 11 17.32% 12 15.49% 13 1.78% 14 -1.26%
Porter McGuffie, Inc. Engineering Measurement and Analysis Services
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Before After
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Result? 2006 installation
Porter McGuffie, Inc. Engineering Measurement and Analysis Services “Overall this was a very successful project for Lafarge” said project manager Nick Trout. “The results exceeded our expectations in terms of providing an excellent quality product that continues to perform within the operating parameters set forth in the justification for the project. We have gone from spending over US $40,000 per month on baghouse repairs to no cost at all. In addition, we are using a lot less compressed air to clean the filter bags and we have reduced the static pressure on the fan by over 4” (10 mm) w.c….” World Cement , May, 2009
Porter McGuffie, Inc. Engineering Measurement and Analysis Services Porter McGuffie, Inc. 544 Columbia Drive – Suite 19 Lawrence, Kansas 66049 V: 785.856.7575 F: 785.856.3658
Recommend
More recommend
