Contents Dew Point... 2 SI Conversions... 2 Output... 2 Input... 2 Solution Condensate-Oil Ratio... 3 SI Conversions... 3 Output... 3 Input... 3 Gas Density... 4 SI Conversions... 5 Output... 5 Input... 5 Oil Density... 5 SI Conversions... 6 Output... 6 Input... 6 Gas Formation Volume Factor... 6 Oil Formation Volume Factor... 7 Two-Phase Deviation Factor... 7 Macros... 8 1
Dew Point ln pp dd = aa 00 + aa 01 XX 0 + aa 02 XX 0 2 3 XX 0 = XX ii ii=1 XX ii = aa ii0 + aa ii1 XX jj + aa ii2 XX jj 2 XX jj = ln RR ss, γγ AAAAAA, γγ gggg Equation 1: Ovalle et al. dew point pressure correlation Where: Oilfield.p d dew point pressure [psia].r s separator gas-stock tank oil ratio [scf/stb].γ API stock tank oil specific gravity [ o API].γ gr reservoir gas specific gravity [1/air]..a 00-a 32 are constants, X 0->X 2 are intermediate variables a00 8.48 a20-0.87528 a01 0.32239 a21-0.29709 a02 0.00477 a22-2.9145 a10 9.8895 a30-0.01691 a11 11.7 a31 0.00151 a12 3.5202 a32-0.81744 SI Conversions Output p dd [kpa] = p dd [psi] 0.145037738 Input R s scf stb = R s ssm3 sm3 5.61458 2
Solution Condensate-Oil Ratio RR vv (pp) = RR vvvv 1 XX 0 XX 1 1 pp pp ii 1 XX 0 XX 0 = aa 00 + aa 01 RR vvvv if RR vvvv aa 30 XX 0 = aa 02 (1 + aa 03 [RR vvvv + aa 04 ]) aa 05 if RR vvvv > aa 30 aa XX 1 = aa 10 + aa 11 RR 12 vvvv if RRvvvv aa 31 XX 1 = aa 13 ln(rr vvvv ) + aa 14 if RR vvvv > aa 31 Equation 2: Garb's correlation for solution condensate-oil ratio below the dew point Where: Oilfield.p pressure of interest [psia].p i dew point pressure [psia].r vi condensate-gas solution ratio at dew point pressure [stb/mmscf].r v(p) condensate-gas solution ratio at pressure of interest [stb/mmscf]. X 0 and X 1 are intermediate variables.a 00->a 31 are constants a00 24.5 a10 4.05 a01-1.37 a11 0.0099 a02 3.91 a12 1.48 a03 2.71 a13 24.3 a04-15 a14-101 a05-0.129 a30 15 a31 150 SI Conversions Output R v sm3 sm 3 = R v stb 5.61458 1000 1000 MMscf Input R vi stb MMscf = R vi sm3 sm3 1000 1000 5.61458 p ii [psia] = p ii [kpa] 0.145037738 p[psia] = p[kpa] 0.145037738 3
Gas Density ρρ gg = MM wwpp ZZZZZZ Equation 3: Gas density from the real gas equation Z = aaaaaaaa_zz pp pppp, TT pppp, 1 pp pppp = pp pp pppp TT pppp = TT TT pppp Equation 4: Compressibility factor of the in-situ gas MM ww = yy oo MM wwww + yy gg MM wwww Equation 5: Apparent molecular mass of the in-situ gas pp pppp = aa 00 + aa 01 MM ww + aa 02 MM ww (ln[mm ww ] + aa 03 ) TT pppp = bb 00 + bb 01 MM ww + bb 02 MM ww (ln[mm ww ] + bb 03 ) Equation 6: Sutton's correlations for pseudo-critical oil properties (works for gas).ρ g In-situ gas density [lb/cuft] [kg/m 3 ].M w apparent molecular mass of the in-situ gas [lb/mol] [g/mol].m wo apparent molecular mass of the stock-tank oil [lb/mol] [g/mol].m wg apparent molecular mass of the surface gas [lb/mol] [g/mol].y g Mole fraction of surface gas in in-situ gas [ ] [ ].y o Mole fraction of stock-tank oil in in-situ gas [ ] [ ].p pressure of interest [psia] [kpa].t temperature of interest [degr] [K].Z compressibility factor of in-situ gas [ ] [ ].R universal gas constant [[psia.cuft]/[mol. o R]] [J/mol/K].p pc pseudo-critical pressure [psia] [kpa].t pc pseudo-critical temperature [degr] [K].a 00->b 03 are constants a00 768.1 b00 135.6 a01-4.919 b01 10.864 a02 1.302 b02-2.81 a03-3.366 b03-3.366 4
SI Conversions Output P pc [kpa] = P pc [psia] 0.145037738 T pc [K] = T pc [ o R] 5 9 Input M w [lb/mol] = M w [g/mol] 1 Oil Density ρρ oo = MM wwpp ZZZZZZ Equation 7: Oil density from the real gas equation Z = aaaaaaaa_zz pp pppp, TT pppp, 0.01 pp pppp = pp pp pppp TT pppp = TT TT pppp Equation 8: Compressibility factor of the in-situ oil MM ww = xx oo MM wwww + xx gg MM wwww Equation 9: Apparent molecular mass of the in-situ oil pp pppp = aa 00 + aa 01 MM ww + aa 02 MM ww (ln[mm ww ] + aa 03 ) TT pppp = bb 00 + bb 01 MM ww + bb 02 MM ww (ln[mm ww ] + bb 03 ) Equation 10: Sutton's correlations for pseudo-critical oil properties.ρ o In-situ oil density [lb/cuft] [kg/m 3 ].M w apparent molecular mass of the in-situ oil [lb/mol] [g/mol].m wo apparent molecular mass of the stock-tank oil [lb/mol] [g/mol].m wg apparent molecular mass of the surface gas [lb/mol] [g/mol].x g Mole fraction of surface gas in in-situ oil [ ] [ ].x o Mole fraction of stock-tank oil in in-situ oil [ ] [ ].p pressure of interest [psia] [kpa].t temperature of interest [degr] [K].Z compressibility factor of in-situ oil [ ] [ ].R universal gas constant [[psia.cuft]/[mol. o R]] [J/mol/K].p pc pseudo-critical pressure [psia] [kpa].t pc pseudo-critical temperature [degr] [K].a 00->b 03 are constants 5
a00 768.1 b00 135.6 a01-4.919 b01 10.864 a02 1.302 b02-2.81 a03-3.366 b03-3.366 SI Conversions Output p pc [kpa] = p pc [psia] 0.145037738 T pc [K] = T pc [ o R] 5 9 Input M w [lb/mol] = M w [g/mol] 1 Gas Formation Volume Factor BB gg = MM ww ρρ gggggg 1 ρρ gg MM wwww yy gg Equation 11: Gas formation volume factor from density MM ww = yy oo MM wwww + yy gg MM wwww Equation 12: Apparent molecular mass of the in-situ gas.ρ g In-situ gas density [lb/cuft] [kg/m 3 ].ρ gsc surface gas density at standard conditions [lb/scf] [kg/sm 3 ].M w apparent molecular mass of the in-situ gas [lb/mol] [g/mol].m wo apparent molecular mass of the stock-tank oil [lb/mol] [g/mol].m wg apparent molecular mass of the surface gas [lb/mol] [g/mol].y g Mole fraction of surface gas in in-situ gas [ ] [ ].y o Mole fraction of stock-tank oil in in-situ gas [ ] [ ] 6
Oil Formation Volume Factor BB oo = MM ww ρρ oooooo 1 ρρ oo MM wwww xx oo Equation 13: Oil formation volume factor from density MM ww = xx oo MM wwww + xx gg MM wwww Equation 14: Apparent molecular mass of the in-situ oil.ρ o In-situ oil density [lb/cuft] [kg/m 3 ].ρ osc surface oil density at standard conditions [lb/scf] [kg/sm 3 ].M w apparent molecular mass of the in-situ oil [lb/mol] [g/mol].m wo apparent molecular mass of the stock-tank oil [lb/mol] [g/mol].m wg apparent molecular mass of the surface gas [lb/mol] [g/mol].x g Mole fraction of surface gas in in-situ oil [ ] [ ].x o Mole fraction of stock-tank oil in in-situ oil [ ] [ ] Two-Phase Deviation Factor pp VV gg + VV oo = ZZ 2pp nn gg + nn oo RRRR Equation 15: Two-phase deviation factor definition.v o oil phase in-situ volume [cuft] [m 3 ].V g gas phase in-situ volume [cuft] [m 3 ].n o oil phase in-situ moles [lb-mol] [g-mol].n g gas phase in-situ moles [lb-mol] [g-mol].p in-situ pressure [psia] [kpa].t in-situ temperature [ o R] [K].R universal gas constant [[psia.cuft]/[mol. o R]] [J/mol/K].Z 2p two-phase deviation factor [ ] [ ] ZZ 2pp = aa 0 + aa 1 pp pppp + aa 2 + aa TT 3 pp 2 pppp + aa 4 2 + aa 5 pppp TT pppp Equation 16: Two-phase deviation factor correlation pp pppp TT pppp.p pr pseudo-reduced gas phase pressure [ ] [ ].T pr pseudo-reduced gas phase temperature [ ] [ ].Z 2p two-phase deviation factor [ ] [ ].a 0->a 5 are constants a0 2.24353 a3 0.000829231 a1-0.0375281 a4 1.53428 a2-3.5639 a5 0.131987 7
Macros Name Purpose Qualifier Units Source Date Module oval_pd Dew Point Gas [psia] Ovalle, Lenn & McCain 2005 Wet Pressure garb_rv Volatized oil-gas Gas [stb/mmscf] Garb 1978 Wet ratio raye_z2 Z-Factor 2-phase [ ] Rayes, Piper, McCain & 1992 Wet Poston sutt_rob Density Oil or [lb/cuft] Sutton 2006 Oil Gas suttopc Critical Pressure Oil or [psia] Sutton 2006 Z Gas suttotc Critical Temperature Oil or Gas [degf] Sutton 2006 Z 8