# Material loading in an empty vessel (or containing the same product)

Model definition   Launch model

This standard model can be used to estimate displacement emissions from products loading operations to an empty vessel (or containing a similar product at same temperature).

Calculated emissions correspond to emission for one batch or one year depending on products charging volumes (yearly products volume or volume corresponding to one batch).

Emissions are calculated using the ideal gas law on the volume of gas that is emitted.
Vapour pressure is determined with Antoine's coefficients of the product. In case of mixture, the equilibrium vapour pressure for each volatile component in the system is calculated by applying Raoult's Law (mixture are composed of miscible organic liquids and not aqueous solutions with solvents traces).

Following hypothesis are assumed for the use of the model:

• Displacement emissions volume correspond to the liquid volume that is charged on the installation,
• The calculated equilibrium vapour pressure represents the gas space composition assuming that the degree of vapour saturation is 100%,
• Mixtures are supposed ideal (activity coefficient are neglect).

Example:

A 3 m3 empty reactor is filled at ambient conditions (25°C and 1 atm) with 2 m3 of MEK. The vessel is vented to atmosphere and the product is splash loaded (saturation factor equals 1.45).
To calculate the vapour emissions, the following element are considered:

• Displaced vapour volume = 2 m3
• MEK vapour pressure at filling conditions: 94.7 mmHg

Calculated emission of MEK corresponding to the filling operation is 1.07 kg. Environmental Models