The concept of mud volume increase due to adding Hematite is as same as the mud volume increase by adding **barite** and **calcium carbonate**. The formula for calculating volume increment is just different only one factor which is **40 **for hematite but 22.5 is usedfor calcium carbonate and 35 is used for barite. Please follow the formula below for determining volume increase because of adding Hematite.

**Volume increase per 100 bbl of mud = 100 x (W2 – W1) ÷ (40 – W2)**

Where; W1 = current mud weight

W2 = new mud weight

Please read and follow the example below for more understanding.

Example: Determine the volume increase when increasing the density with hematite from 10.0 ppg (W1) to 13.0 ppg (W2):

Volume increase per 100 bbl of mud =100 x (13.0 – 10.0) ÷ (40 – 13.0)

Volume increase per 100 bbl of mud = 11.11 bbl

If you have total volume of 500 bbl of mud, the volume increase due to adding calcium carbonate will be equal to 55.56 bbl (11.11 x 500 ÷ 100).

**Please find the Excel sheet used to calculate how much volume increased due to adding Hematite.**

**Ref book: ** **Formulas and Calculations for Drilling, Production and Workover, Second Edition**