SOLIDS CALCULATIONS

•To completely analyze a drilling fluid for the amount of solids present, the following calculations should be used.
Low Density, UnweightedMud (No Oil, No Salt)
•Procedure:
–Measure Mud Density, D (kg/m3)
–Measure Bentonite from Methylene Blue Test, MBT (kg/m3)
•Volume Fraction of Solids, Fs
•Fs = [(D /1000) –1] X 0.625
–Volume Fraction of Water, Fw
•Fw= 1 –Fs
–Total Amount of Low Gravity Solids, LGS (kg/m3)
•LGS = D –(FwX 1000)
–Amount of Drilled Solids, DS (kg/m3)
•DS = LGS –MBT
Low Density, UnweightedMud (With Oil, No Salt)
•Procedure:
–Measure mud density, D (kg/m3)
–Measure Bentonite from Methylene Blue Test, MBT (kg/m3)
–Read the volume fraction of oil from the retort, Fo
•Volume Fraction of Solids, Fs
–Fs = [(D / 1000 –1) + (0.2 X Fo)] X 0.625
•Volume Fraction of Water, Fw
–Fw= 1 –(Fs + Fo)
–Total Amount of Low Gravity Solids, LGS (kg/m3)
•LGS = D –[(FoX 800) + (FwX 1000)]
–Amount of Drilled Solids, DS (kg/m3)
•DS = LGS –MBT
Low Density, UnweightedMud (With Oil, No Salt)
•Note: The oil fraction is obtained from the retort. The volume fraction of solids is obtained from the formula. This is done because small errors in reporting the volume fraction of solids can occur when taken from a retort in a unweightedlow density mud.
Low Density, UnweightedMud (With Salt, No Oil)
Note: These calculations should be used for fluids containing chlorides over 10,000 mg/L.
•Procedure:
–Measure Mud Density, D(kg/m3)
–Measure chloride content, Cl(mg/L)
–Measure Bentonite form Methylene Blue Test, MBT(kg/m3)
–Read the volume fraction of water from retort, Fw
–Read the volume fraction of Oil from retort, Fo
–Read the volume fraction of Salt in the mud from Figure 1.1, F Salt
Low Density, UnweightedMud (With Salt, No Oil)
–Amount of Salt in Mud, S(kg/m3)
•S = [(1.65 X Cl) X (Fw+ Fsalt)] / 1000
–Amount of Low Gravity Solids, LGS(kg/m3)
•LGS = 1.625 {D –[1000 (1 –Fsalt) ] + (160 X Fo) } –(0.375 X S)
–Amount of Drilled Solids, DS(kg/m3)
•LGS = LGS–MBT
–True Volume Fraction of Water, True Fw
•True Fw= [1.625 (1 –Fsalt)] –[(D + S) / 1600]
–Volume Fraction of Solids, Fs
•Fs = 1 –True Fw

Low Density, UnweightedMud (With Salt, With Oil)
Note: These calculations should be used for fluids containing chlorides over 10,000 mg/L.
•Procedure:
–Measure Mud Density, D(kg/m3)
–Measure Chloride content, Cl(mg/L)
–Measure Bentonite form Methylene Blue Test, MBT(kg/m3)
–Read the volume fraction of water from retort, Fw
–Read the volume fraction of Oil from retort, Fo
–Read the volume fraction of Salt in the mud from Figure 1.1, Fsalt

Low Density, UnweightedMud (With Salt, With Oil)
–Amount of Salt in Mud, S(kg/m3)
•S = [(.65 X Cl) X (Fw+ Fsalt)] / 1000
–Amount of Low Gravity Solids, LGS(kg/m3)
•LGS = 1.625 {D –[1000 (1 –Fsalt) ] + (160 X Fo) } –(0.375 X S)
–Amount of Drilled Solids, DS(kg/m3)
•LGS = LGS–MBT
–True Volume Fraction of Water, True Fw
•True Fw= [1.625 (1 –Fsalt)] –[(D + S) / 1600]
–Volume Fraction of Solids, Fs
•Fs = 1 –(True Fw+ Fo)
Weighted Systems
•Procedure:
–Measure the mud density, D(kg/m3)
–Measure the Chlorides, Cl(mg/L)
–Measure the Bentonite from Methylene Blue Test, MBT(kg/m3)
–Read the volume fraction of water from the retort, Fw
–Read the volume fraction of oil from the retort, Fo
–Read the volume fraction of Salt in the mud from Figure 1.1, F Salt
–Determine the volume fraction of solids from the retort, Fs
Weighted Systems
–Amount of Salt in mud, S (kg/m3)
•S = (1.65 X Cl) (Fw+ F Salt)/1000
–Amount of Total UndissolvedSolids, TS (kg/m3)
•TS = D –[(FoX 800) –(FwX 1000)] –S
–Average Relative Density of UndissolvedSolids, Dr
•Dr = TS / (Fs –F Salt) X 1000
–Amount of Barite in Mud, BAR (kg/m3)
•BAR = TS X [2.62 –(6.82/Dr)]
–Amount of Low Density Solids, LDS (kg/m3)
•LDS = TS –BAR
–Amount of Drilled Solids, DS (kg/m3)
•DS = LDS –MBT



Salt Volumes graph