Retort analysis is the method to determine solid and liquid components in the drilling fluid. In this article, we will adapt mass balance and retort analysis data to determine solid density in the mud.

Mass balance for mud is listed below;

We can rearrange the Euqation#1 in order to determine the solid density

In the report analysis, the volume is presented in percentage and summation of solid and liquid fraction equals to one.

The unit of each parameter is described below;

Vm = mud volume, %

ρ_{m }= mud density, ppg

Vw = water volume, %

ρ_{w }= water density, ppg

Vo = oil volume, %

ρ_{o }= oil density, ppg

Vs = solid volume, %

ρ_{s }= solid density, ppg

**Note:** this is not only cutting weight but it includes all weights of solid (cutting and weighting material).

**Example:** Mud weight used for the report is 12.0 ppg and the result from the analysis showing in the following percentage;

Base oil = 60%

Solid = 35 %

Water = 5%

Base oil weight = 7.0 ppg

Water weight = 8.6 ppg

ρ_{s }= 21.06 ppg

Total density of solid in the drilling mud is **21.06** ppg.

**Reference book =>** Formulas and Calculations for Drilling Operations