Determination of Volatile Matter in Sludge

Determination of volatile matter reduction in sludge is complicated because of the changes occurring during sludge digestion.

The calculation used to determine percent volatile matter (VM) reduction is

[%VM_in – %VM_out] X100

% of Volatile Matter Reduction (VM) = ——————————-

[%VM_in – (%VM_in X % VM_out)]

Using the digester data provided below, Determine the percent volatile matter reduction for the digester.

Raw Sludge Volatile Matter = 72%; Digested Sludge Volatile Matter = 51%

According to the afore said formula, % VM (reduction) =59%