Refer to the table for selecting the K value of the heat exchanger

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        When choosing a heat exchanger, one often struggles with determining the appropriate value for K. If this value is not chosen correctly, it can result in the heat exchange area of the equipment being either too large or too small. Here is a table to help with this decision; surely those who find it useful are hoping for such a table. Range of overall heat transfer coefficients K for shell-and-tube heat exchangers: The total fouling thermal resistance included in K is expressed in W/(m²·°C) or (m²·°C)/W.

Liquid–liquid media:
Diluted asphalt: 57–1100; 0.0018
Monoethanolamine or diethanolamine (10%–25% in water): 800–11000; 0.00054
Softened water: 1700–28000; 0.00018
Fuel oil: 85–1400; 0.0012
Gasoline: 340–5700; 0.00054
Heavy oil: 57–2300; 0.0007
Hydrogen-rich reformate: 510–8800; 0.00035
Kerosene or gas oil: 140–2800; 0.00088
Trichloroethylene: 230–2800; 0.00026

Jacket water: 1300–17000; 0.00035

Lubricating oils:
Low-viscosity lubricating oil: 140–2800; 0.00035
High-viscosity lubricating oil: 230–4600; 0.00054
Lubricating oil: 60–1100; 0.0011

Naphtha: 280–4000; 0.00088
Organic solvents: 280–8500; 0.00054
Organic solvent solutions: 200–5100; 0.00054
Tall oil derivatives and vegetable oils: 110–2800; 0.0007

Sodium hydroxide solution (10%–30% in water): 570–14500; 0.00054
Water: 1100–14200; 0.00054

Wax distillate: 85–1400; 0.00088
Condensing steam–liquid media:
Alcohol vapor: 570–11000; 0.00035
Bitumen at 232°C: 230–3400; 0.0011
Therminol vapor: 340–4600; 0.0007
Therminol liquid: 460–6800; 0.00026
Gasworks tar: 230–2800; 0.00097
High-boiling-point hydrocarbons (under vacuum): 110–2800; 0.00054
Low-boiling-point hydrocarbons (at atmospheric pressure): 460–11000; 0.00054
Hydrocarbon vapors (in condensers): 140–2300; 0.0007

Condensing steam–liquid media:
Organic vapors: 570–11000; 0.00054
Organic vapors with high non-condensable gas content (at atmospheric pressure): 110–3400; 0.00054
Organic vapors with low non-condensable gas content (under vacuum): 280–6800; 0.00054
Kerosene: 170–3400; 0.0007
Naphtha: 280–4300; 0.00088
Reflux steam from pressure regulators: 460–6800; 0.00054
Water vapor: 2300–57000; 0.00088
Steam for heating No. 6 fuel oil: 85–1400; 0.00097
Steam for heating No. 2 fuel oil: 340–5100; 0.00044
Sulfur dioxide: 850–11000; 0.00054
Tall oil derivatives and vegetable oils (as vapor): 110–2800; 0.0007
Aromatic vapor azeotropes: 230–4600; 0.00088

Gas–liquid media:
Air, N₂, etc. (compressed): 230–4600; 0.00088
Air, N₂, etc. (at atmospheric pressure): 57–2800; 0.00088
Water or compressed air/N₂: 110–2300; 0.00088
Water or compressed air/N₂ (at atmospheric pressure): 30–1100; 0.00088
Hydrogen mixed with natural gas: 460–7100; 0.00054

Vaporizers:
Anhydrous oxygen: 850–17000; 0.00026
Chlorine: 850–17000; 0.00026
Light oil used for chlorine heat transfer: 230–3400; 0.00026
Propane, butane, etc.: 1100–17000; 0.00026
Water: 1420–23000; 0.00026

Recommended values for overall heat transfer coefficient K in air coolers (based on bare tubes):
Condensation: K = 625 W/(m²·°C)
Liquid cooling: K = 710 W/(m²·°C)
Gas cooling: K = 345 W/(m²·°C)
Operating pressure and pressure drop: kPa(g)
Ammonia: 625
Jacket water: 710
Air or flue gas: 345; 0.7–3.5
Freon-12: 400
Diesel fuel: 140; 690; 13.8; 110
Gasoline: 460
Light gas oil: 370; 690; 341; 70
Light hydrocarbons: 510; 480
Hydrocarbon gases: 241; 7200
Light naphtha: 430; 400; 862; 21200
Heavy naphtha: 370
Reformer effluent: 400; 690; 34460
Exhaust steam from reformers: 400
Residual oil: 85
Ammonia reactor fluid: –480
Low-pressure steam: 770
Tar: 40
Top-of-tower steam: 370