What happens if my process unit receives more feed than it can handle?

For example, a hydrotreater may have a maximum capacity of 20,000 bbl/day, a minimum capacity of 5000 bbl/day and a max unprocessed limit of 10,000 bbl/day. If 15,000 bbl/day of feed was sent to the hydrotreater there would be no problems processing the feed. If 25,000 bbl/day was sent to the unit, 20,000 bbl/day would be processed, and the remaining 5000 bbl/day diverted to another stream. If 35,0000 bbl/day of feed was sent to the unit, 20,000 bbl/day would be processed. However this would leave 15,000 bbl/day unprocessed which violates the Max Unprocessed condition. In this case the throughput to the crude unit would have to be reduced in order to reduce the hydrotreater feed to 30,000 bbl/day (20,000 capacity + 10,000 allowed unprocessed). However this would result in many units running at less than capacity and so throughput warnings would be shown for these units.

Unit Feed Limits

Particular process units may have property constraints for their feed streams which can be defined on the Unit Feed Limits page

Particular process units in the refinery schematic may have constraints for their input feed stream. Maximum and minimum property values can be applied to the input feed using the Unit Feed Limits page. The different possible limits are:

• Constrain Min - the minimum value for the stream property

• Constrain Max - the maximum value for the stream property

Select the check box next to each value to enable the corresponding constraint.

Operational Mode

The Operational Mode page defines the operating parameters for the process units in the refinery, such as the cut points between streams in the distillation units. By defining different operating modes, you can evaluate several refinery configurations to determine the most profitable way to process a feedstock.

The Operational Mode grid supports copy and paste from other software applications such as spreadsheets.

Product Specifications

The Product Specifications page shows the property limits applied for the final products of the refinery

For each different refinery product, the Product Specifications page shows the final property constraints which the products must meet (Product specifications). The specifications can be configured using:

• Product - the product type

• Description - the name of the product

• Property - the property with a required specification

• Unit, Minimum & Maximum - the measurement unit, minimum property value and maximum property value respectively.

Blending Matrix

The Blending Matrix page shows which refinery streams can be pooled into final products

The Blending Matrix shows which refinery streams can be pooled to make a final product. The different refinery streams are shown in the left-hand rows of the grid, and the final products in the top column headers of the grid (Blending matrix).

When editing the matrix, select the checkbox in a cell to enable the stream on that row to be blended into the product on that column.

Yield Constraints

The Yield Constraint page shows absolute product limits as well as warning ranges for production

For each final product yield, constraints can be applied to ensure a minimum or maximum amount of product is produced (Yield constraints). The options for constraining the yield are:

• Constrain - a minimum or maximum value that must be met

• Warning - a value which generates a warning if the minimum or maximum is not met.

When editing the constraints, click any cell and start typing to enter a value. Select the check box in a cell to enable the corresponding constraint.

Feedstock Settings

The Feedstock Settings page allows the different feedstocks that can be imported to be configured, including their properties and pricing

Feedstock settings allows imported feedstocks to be added to the case. These are processed materials that can be included in the blending pool along with the refinery streams. Several types of feedstock are available by default, and when these are activated the properties of the imported feedstock should also be set to allow for their correct use in blending.

Product Pricing Cases

The Product Pricing Cases page shows the value of each of the final refinery products and includes the cost of any materials which must be purchased

The ability to select Pricing Mode, Pricing Date, Price Averaging, Source, and Quote is available only if the optional Platts Pricing Feed has been licensed.

The Product Pricing Cases page shows the value of each the products produced by the refinery. For each product the sale value must be entered, along with the unit by which the product is sold (either by weight or by volume). See Product pricing.

For each product, a Reference Density can be included. This is used to convert between weight and volume units and takes precedence over any volume calculated by Assay during optimisation.

Crude Pricing Cases

The Crude Pricing Cases page shows the cost of purchasing each of the crudes that may be processed in the refinery

The ability to select Pricing Mode, Pricing Date, Price Averaging, Source, and Quote is available only if the optional Platts Pricing Feed has been licensed.

The Crude Pricing Cases page allows the cost of each crude to be entered. The purchase price of the feed should be entered per barrel (Crude pricing).

Crude Freight Cases

The Crude Freight Cases page shows the cost of shipment for particular crudes to the refinery

The cost of shipping each traded crude to a particular location can be included on the Crude Freight branch of the Netback case. See Add crude freight.

The Crudes page shows those crudes chosen for Netback analysis

The crudes which are included in the actual Netback analysis must be added on the Crudes page. In order for Netback to calculate the final Netback value for the crudes, they must also have a Crude Price entered as well as related Crude Freight costs. See Add crudes to your netback analysis.