MethanolInjection.xlsThis spreadsheet calculates the minimum amount of required inhibotor usage.

Input Data:

Gas flow rate: 10 MMscfd

0.7 air = 1

900 psia

90

64

40

48 lb/MMscf

9.6 lb/MMscfInhibitor solution density: 6.64 ppg

100 Wt %

Intermediate Calculations:

38.4 lb/MMscf

32

2335

24Inhibitor requirement based on Hammerschmidt's method:

= 24.75 Wt %

Liquid phase:

= 12.63 lb/MMscf

Gas phase:

= 1.05

Inhibitor requirement: 25.99 lb/MMscf

System total:

Gas specific gravity (gg):

Minimum pressure (pm):

Inlet gas temperature (ti): oF

Hydrate temperature pm: oF

Operating temperature (to): oF

Water content at ti and pm:

Water content at to and pm:

Inhibitor concentration (Win):

Water to be removed from gas (wG):

Molecular weight of inhibitor (MW)inh:

Hammerschmidt constant for inhibitor (KH):

Depression of hydrate formation temperature (Dth): oF

Instructions:1) Update input data in blue;2) View result.

W h=(MW )inh Δth

(MW )inh Δth+K H×100

I 100=W G

(100W out

−100W in

)

lbm MeOH/MMscf

WT % NeOH in Water= f (P , t )

Inhibitor requirement: 38.62 lb/MMscfDaily injection rate: 386.18 lb/day

58.16 gal/dayHourly injection rate: 2.42 gal/hour

Check:

= 12.63I 100=WG

1+KH

(MW )inh Δth−100W in