Transcript No Slide Title

Heuristics
12 Oct 12
Homework: Problem 11.1 Turton
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Example
Estimate size of heat
exchanger E-105
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In Class
Exercise
Estimate size of
reboiler E-106
Given:
• mps (medium pressure steam) = 10 barg
• T-101 operates at 3 bar
• From simulation, reboiler duty = 2,512,500 W
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Heat Exchangers
Additional Experience-Based Principles:
Gael D. Ulrich and Palligarnai T. Vasudevan, Chemical Engineering Process Design and
Economics, a Practical Guide, 2nd ed., Process Publishing, Durham, NH, 2004
Posted on the website will be Ulrich’s guide/shortcut/rules of thumb for
heat exchanger design and flowsheet preparation.
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Ulrich, 2004
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Ulrich, 2004
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www.pfaudler.com
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www.pfaudler.com
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Spiral-like HE
ACHEMA, Frankfurt, June 2012
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ACHEMA,
Frankfurt, June 2012
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Air Cooled Heat Exchangers
Ulrich, 2004
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Air Cooled Heat Exchangers
Ulrich, 2004
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Air Cooled Heat Exchangers
Air cooled heat exchangers can be used when:
• Cooling water source not readily available
• Cooling water systems adds complexity or cost to facility
• Lower operating / maintenance cost could be achieved
Applications.. air coolers are installed throughout the world in the following
applications:
• Forced and induced draft air cooled heat exchangers
• Recirculation and shoe-box air cooled heat exchangers
• Hydrocarbon process and steam condensers
• Large engine radiators
• Turbine lube oil coolers
• Turbine intercoolers
• Natural gas and vapor coolers
• Combustion pre-heaters
• Flue gas re-heaters
• Lethal service
• Unique customizations
www.gearainey.com
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Air Cooled Heat Exchangers
Minimizing Air Cooler Costs
GEA Rainey Corporation has developed a short list of points to help you create the most
economical design and assist with an initial design; most of the time GEA can provide
more economical designs.
• Maximize tube length while maintaining >=40% fan coverage
• Design aircooler with a 1 to 3 ratio. For example, if your cooler is 30’ long it should
typically be around 10’ wide. This helps reduce the header size, the most expensive
portion of an aircooler, while still maintaining proper fan coverage.
• Minimize tube rows to increase heat transfer effectiveness of area, minimize header
thickness. Typically between four to six tube rows
• Try and maintain 1” tube diameters, depending on service. Even high viscosity
services that appear to benefit from larger diameter tubes can typically be designed
cheaper with more 1” diameter tubes.
• Use a counter-current flow where possible as it reduces surface and potentially
minimize header plate thickness.
• Increase your allowable pressure drop. This allows more passes in the bundle reducing
the cooler size.
www.gearainey.com
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Air Cooled Heat Exchangers
Ulrich, 2004
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Ulrich, 2004
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Ulrich, 2004
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Ulrich, 2004
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Guidelines for Equipment Design
Ulrich, 2004
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Ulrich, 2004
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Ulrich, 2004
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