Add crudes to the blend analysis

You must provide a list of the crudes that constitute the blSelect crudesnd, together with start ratios or minimum and maximum proportions in the final mixture.

Click the Add button at the bottom of the Blending page to add one or more crudes to the blend list. The Select Crudes dialog opens. See Select crudes.

Tip

Another way to add a blend constituent is to double click on any empty area of the Blending page.

You can also add multiple items at a time from the database into the blend crude list by copying and pasting:

Select the crudes you want to add in the database window.

Press Ctrl + C or click the Copy button in the Clipboard group of the Home ribbon tab.

Do either of the following:

Click Paste in the Clipboard group of the Home ribbon tab.

Right click in the blend crudes list and select Paste from the context menu.

Once you have added a crude, you can edit it in the following ways:

• To replace the crude, double click either the Reference or the Name cell. The Select Crudes dialog opens, allowing you to choose another crude.

• Change the start ratio of the crude in the blend by double clicking the value in the Start Ratio column and typing a new value. The ratio determines the proportion, by either weight or volume, of the crude in the final blend mixture. For example, a mixture of Arab Light, Kirkuk Blend and Basrah Light in the ratio 1:2:3 gives a blend that is one sixth Arab Light, one third Kirkuk Blend, and one half Basrah Light. The values in the % Wgt and % Vol columns, showing the equivalent percentages of the crude by weight and by volume, are updated automatically when you change the ratio.

• To change the constraints for a crude, double click the value you want to change in the Min % or Max % column and type in a new value.

  

Start ratios and limits

The BlendAnalysis tool allows you to enter a start ratio and constraints (maximum and minimum allowed percentages) for the analysis.

It is often the case that the problem you are trying to solve has multiple possible solutions (for example, given one API measurement, and multiple constituent crudes, there may be many possible ways to blend these constituents to give the measured API value). If you already know approximately what the ratios are, you can provide this data for your analysis, allowing the BlendAnalysis tool to resolve any ambiguities in the case of multiple solutions.

Also, in some cases, you know that there is definitely not more than (or less than) a given percentage of a particular crude in the blend you are analysing. You may impose these constraints by specifying the limits (in either weight or volume proportion). Any solutions found by BlendAnalysis will be consistent with these constraints.

Managing the list

You may add items to the blend crude list, edit items in the list and remove items from the list in a number of ways:

• Right click on the crude list and choose Add, Edit or Remove from the context menu.

• Add a blend item by double clicking in the white space below the current list of crudes in the blend.

• Click the Add, Edit and Remove buttons at the bottom of the crude list.

  Weight or Volume option

  

The start ratios may either be in weight or volume proportions. To switch between these two options, choose the appropriate option from the Blend Using drop-down menu at the bottom of the page.

Measurement grids

You can copy and paste crudes in the blend crude list to other crude lists in Assay, or to other programs using cutting, copying and pasting functionality. This can be accessed in a number of ways:

• Click the Cut, Copy and Paste buttons in the Clipboard group of the Home ribbon tab for cut, copy and paste respectively.

• Right click on the crude list and choose Cut, Copy and Paste from the context menu.

• Use the keyboard shortcuts Ctrl + X, Ctrl + C and Ctrl + V.

Copying an item will place a copy of the information associated with that crude item onto the Clipboard, from where it can be pasted into other crude lists, or into an external application, such as Microsoft® Excel®. Conversely, data formatted in a recognisable way may be pasted from external programs into the Assay crude lists. Cutting an item copies it to the Clipboard, before permanently removing it from the crude list.