The glycerol phase is a by-product of biodiesel production. The composition depends on the purity of the methanol and methoxide, impurities, FFA content and water in the feedstock oil and is a mixture of glycerol, methanol and soaps. Also the sedimentation time parameter and temperature influence the composition of crude glycerol.

Crude glycerol is also a feed supplement and is recommended for animal feed, where methanol is removed by distillation.  In cattle it increases milk production and broilers will grow faster.

All the raw glycerine resulting from the biodiesel settling process is collected in a 15 m³ tank.