Water salinity from density equation

Water salinity from density equation

Handy equation to get the formation water (brine) salinity from the density at standard conditions obtained by the data regression with a stage line.

Water salinity from density equation

Math and Physics

$C_{mg/l} = 25000 \times (SG_w - 1) \times 62.428$

Example. Calculating water salinity from density

Example source

Input data

$\rho_w$ = 65.4 lbm/ft3

Calculate water salinity in weight percent solids?

Solution

$SG_w = \rho_w/62.428=1.0476$

$C_{mg/l} = 25000 (1.0476 - 1) 62.428 = 74289.32$

$C_{ppm} = 74289.32 / 1.0476 = 70913.8$

$C_W = 70913.8 / 10000 = 7.1 %$

Nomenclature

$C_{ppm}$ = water salinity / solids concentration, ppm

$C_{mg/l}$ = water salinity / solids concentration, mg/l

$C_W$ = weight percent solids, %

$SG_w$ = water specific gravity, dimensionless

See also

Water solids concentration