Example for Balance types

Assume that the primary balance type in the Option dialog is Volume. Assume also that you wish to balance both mass and volume in process objects but only volume in tank objects. In that case, you would select the balance type "BOTH" in the Information tab of all your model’s process objects. In the tank objects, you do not need to manually select the "VOLUME" balance type since it will already be set to that by virtue of the fact that the primary balance type in the Option dialog is Volume. When you reconcile the model, the reconciled flow rate for stream objects connected to a process object will be both mass and volume but the reconciled values for tank objects will be only volume values.

In the below example, the MnV_PROCESS process balance type is "BOTH" while the V_TANK tank object is allowed to default to a "VOLUME" balance. After you reconcile this example, you can see that the volume inventory of the V_TANK tank object is reconciled but the streams which are connected to the MnV_PROCESS process are reconciled for both mass and volume.

Expressed another way, the balance envelope around the process ends up balanced for mass but the balance envelope around the tank is not balanced for mass.

AVEVA Production Accounting calculates the reconciled volumetric quantity by density conversion for the isolated stream in running only mass reconciliation.

Keep in mind that the reconciled volumetric quantity by density conversion is calculated only when the reconciled mass quantity after mass reconciliation is changed.

It means that if the reconciled mass quantity did not get changed (the reconciled mass quantity after reconciliation is same with the previous reconciled mass quantity), the reconciled volumetric quantity remains unchanged.