Hydrate Inhibitor (Hammerschmidt) Calculator
Determine required weight percentage and daily volumetric injection rate of Monoethylene Glycol (MEG) or Methanol to prevent gas hydrate blockages.
Subcooling & Water Production
ΔT = Hydrate Formation Temp - Lowest Operating Temp + 5°F safety
Standard lean MEG: 80% - 90% wt
MEG ~ 5-15 lb, MeOH ~ 50-120 lb
Inhibitor Dosage Results
Required Rich Concentration (X_rich):
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Daily Lean Injection Volume:
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Pure Inhibitor Mass Rate:
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Injection Pump Rate:
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Gas Vapor Loss Total:
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Water-Phase Dilution Ratio:
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Thermodynamic Hydrate Inhibition (THI)
Thermodynamic inhibitors lower the chemical potential of water through hydrogen bonding, shifting the hydrate equilibrium curve to lower temperatures and higher pressures (freezing point depression). Monoethylene Glycol (MEG) and Methanol are the two dominant chemicals injected into subsea Christmas trees and flowlines.
Hammerschmidt Equation (1934)
ΔT = (2330 · X) / [MW · (100 - X)]
Where $Delta T$ is hydrate temperature depression in °F, $X$ is inhibitor concentration in weight percent of the aqueous phase, and $MW$ is molecular weight ($62.07 ext{ g/mol}$ for MEG, $32.04 ext{ g/mol}$ for Methanol).