reboiler

1. REBOILERS IN PROCESS INDUSTRIES
Presented By:
Jay Jawalge (11920039)
Rupali Kadam (11920081)
Karthik Iyer (11810069)
Payal Khandagale (11920014)
Arjun Phad (11920021)
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2. Content
• Reboiler
• Types of reboiler
• Choice of type
• Selection factors of reboiler type
• Variables influence boiler design
• Advantages & disadvantages
• Case study
• Conclusion
• References
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3. REBOILER: Heat Exchanger
• Used with distillation columns to vaporise a
fraction of the bottom product
• Provide vapor flow up a column and acts as an
additional theoretical stage below the
trays/packing
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4. Fig. 2, Industrial reboiler, Ref. [2]
Fig. 1, Schematic of industrial reboiler, Ref. [1]
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Continued…

5. Types of reboilers
• Forced circulation
• Natural circulation (Thermosyphon)
• Kettle Type
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Fig. 3, Classification of reboiler

6. Forced Circulation Reboiler
• Designed to operate liquid
full
• Flashing occur as the liquid
crosses the control valve
• Valve should be located
close to the column shell
• Offer greater flexibility than
thermosyphons
• Elevation is less critical due
to pump and control valve Group 7 6
Fig. 4, Vertical Forced circulation reboiler

7. Continued…
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Fig. 5, Horizontal forced circulation reboiler

8. Thermosyphon reboilers
• Return piping to the
column must be sized for
two-phase flow
• Operates on
thermodynamic
principles, rather than
gravity
• Design detail is important
• Operation is simple, but
difficult to design for a
wide operating range
• Proper elevation is critical
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Fig. 6, Vertical thermosyphon reboiler

9. Continued…
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Fig. 7, Horizontal thermosyphon reboiler
Fig. 8, Horizontal industrial thermosyphon reboiler

10. Kettle Type reboilers
• Vapor-Liquid disengagement
occurs in the vapor space,
therefore return piping is
sized for all-vapor flow.
• Proper elevation is critical
to kettle reboiler operation.
• Kettles have a large
footprint, but require less
elevation than a
thermosyphon.
• Works by gravity, rather
than thermodynamics.
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Fig. 9, Kettle reboilerc

11. Internal reboiler
• Boiling takes place in the
pool of liquid at the bottom
of the tower
• Boiler in conventional
distillation column
• Distillation column size gives
the limitations
• Part of every distillation
column
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12. Choice of type
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Fig. 11, Choice of type of reboilers, [3]

13. Selection factors of Reboiler Type
• Cleanability (Fouling)
• Corrosion
• Pressure
• Temperatures
• Heating medium
• Boiling fluid characteristics
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14. Variables that influence the reboiler
design
• Pressure drop (pressure gradient)
• Mass velocity
• Flow pattern (parallel, cross, counter types)
• Tubes orientation (vertical or horizontal)
• Critical heat flux condition
• Thermal hydraulics
• Reboiler duty
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15. Advantages & Disadvantages
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16. Case Study: Evaluation of reboiler temperature
retention time on MEG degradation products at
varying MEG concentrations
Paper specification
 Year of publication: 31
July 2020
 Journal: Journal of
Petroleum Science and
Engineering
Key words
 MEG: Mono Ethylene
Glycol
 Thermodynamic hydrate
inhibitor
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17. Problem statement
• MEG thermal degradation process can occur due to
dissociation to organic acids including glycolic, acetic
and formic acids.
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Fig. 12, Ref[6] Proposed dissociation products of ethylene glycol within oxygen
contamination under high temperature conditions

18. Methodology
1. Stock solution preparation
2. Distillation system
3. MEG concentration measurement (Refractometer)
4. Distillation calculations (9 internal configuration)
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19. Group 7 19
Fig. 12, Distillation setup

20. Result and discussion
1. Effect of the reboiler temperature retention time on MEG
degradation products
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MEG degradation product increase percentage for different MEG concentrations

21. Continued…
2. Effect of the reboiler temperature on the total organic
acids accumulation
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22. Conclusion
• Operating the reboiler at higher temperatures to
achieve better separation by removing surplus water
and produce high purity lean MEG for offshore
recycling and reinjection at the wellhead
• However, this process results in an increase of
degraded MEG and will require further new
quantities of MEG to compensate the degraded MEG
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23. Reference
[1] Parisher, R. A., & Rhea, R. A. (2012). Mechanical
Equipment. Pipe Drafting and Design, 112–133.
doi:10.1016/b978-0-12-384700-3.00006-2
[2]https://www.arab-oil-naturalgas.com/what-are-reboiler-
types/
[3] wp.auburn.edu
[4] doi: 10.1615/AtoZ.r.reboilers
[5] doi:https://doi.org/10.1016/j.petrol.2020.107735
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24. [6] ROSSITER JR, W. J., BROWN, P. W. & GODETTE, M.
1983. The determination of acidic degradationproducts
in aqueous ethylene glycol and propylene glycol
solutions using ion chromatography. Solar Energy
Materials, 9, 267-279.
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Continued…

25. THANK YOU
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