Net oil in tonnes from the liquid rate and water cut
Oil and water rates in m³/d and t/d from the metered liquid rate and water cut, the mixture density, and the conversion between volume and mass water cut.
q_o = q_l · (1 − W_v); Q_o = q_o · ρ_o; Q_w = q_l · W_v · ρ_wρ_l = ρ_o · (1 − W_v) + ρ_w · W_v; W_m = W_v · ρ_w / ρ_lW_v = W_m · ρ_o / (W_m · ρ_o + (1 − W_m) · ρ_w)The liquid rate is at surface conditions after gas separation, the oil density at 20 °C. The net mass of sales oil is lower by the chloride salts and sediment too — they are not included here.
Source: Mass balance of the water-oil mixture (well production accounting)
Inputs
You can change a field's unit: the value is converted to the formula's units automatically.
From the test separator or metering unit — at surface conditions, after the gas is separated.
Water-cut meters and settling a sample in a graduated vessel give the volume fraction; a laboratory analysis (Dean-Stark) may be reported by mass.
Of the separated (dead) oil; usually 800–900 kg/m³.
Formation water is usually 1 010–1 180 kg/m³; take it from the water analysis.
Unit converter for this formulaLiquid rate · Density and °API · Mass rate and emissions · Fraction and percent
- m³/d1
- m³/h0.0416667
- L/s0.0115741
- L/min0.694444
- m³/min0.000694444
- bbl/d6.28981
- Mbbl/d0.00628981
- ft³/d35.3147
- US gpm0.183453
- bbl/min0.00436792
A day is 24 hours.
- q_o — Oil rate by volume–
- Q_w — Water rate–
- ρ_l — Density of the water-oil mixture–
- W_v — Water cut by volume–
- W_m — Water cut by mass–
More in Production metering
Results are engineering estimates from standard formulas; for design decisions check them against the codes, project documents and specialists' calculations. The formulas carried over from the original set are unchanged, and their errors are described in the notes.