Calculate stream values

The Stream Values page shows the results of stream value analysis in your case. Stream values show the change in objective function resulting from adding an extra free unit of a stream. See Stream Values for an explanation of the principle behind stream values and some examples.

Cells in the grid are shaded green or blue according to whether the stream value contribution to the objective function is positive or negative. The shading changes according to the absolute value of the contribution.

The different rows of the grid show you a breakdown of the effects of the extra unit of flow. The rows are divided into three main categories:

• Flow: The effect on the flow of material upstream and downstream (shown in the Direction column).

• Property: The effect on the stream properties. For example, an extra unit of a feedstock could result in a higher sulfur content, which would have a negative effect on the objective function.

• Other: The effect on other quantities not included in the two categories above.

The sum of all the contributions for each category is displayed at the bottom of the group of rows belonging to the category. A row at the bottom of the table shows the overall contribution from all categories for each feedstock.

Note: Stream values are shown on the feed pipes to the process units. Since stream values are mode-specific, the feed pipe must also have modes matching these. This may require adding modes upstream of the process units for the feed assets. For example, if a process unit has a winter and a summer mode and a feed manifold, this feed manifold would also need a winter and a summer mode.

In order for stream values to be calculated, you must select the Stream Values check box in the Result Retrieval Settings page of the Run Settings dialog box.

If this setting is not enabled, a warning appears at the top of the Stream Values page, with a link you can click to enable the setting.