Types of configuration objects

Objects

Description

Stream objects

These objects are the work horses. They contain the measured and reconciled values. They connect Balance Objects.

Balance Objects

These objects include the objects around which a balance envelope exists, as well as the shipment and receipt objects that mark the plant periphery.

Tank, Process, Node

These objects have both input and output streams; therefore a balance envelope exists around them.

Tanks are special in that they have inventory.

Process objects serve to allow streams to come together or split.

A process object may represent a reactor, a distillation column, or a process unit. It is possible to attach an image to a process object so that the flowsheet will reflect the nature of the real world refinery process represented.

Nodes serve to allow streams to come together or split. In that respect, they are similar to process objects, but since they do not represent real world processes you cannot configure an image for the node.

The reconciliation algorithm treats nodes and processes similarly, by enforcing a balance around them.

Model connectors

These objects permit you to connect the models and link them so you can model parts of your plant separately.

Taken together, all models joined by model connectors should model the entirety of your plant.

This ability to link together separate models is what allows you to model separate process units and tie the units together as a whole without remodeling them.

Model Connectors are like special node objects whose inputs are in one model and whose outputs are in another.

Since Model Connectors have input streams coming from one model and output streams in another model, the reconciliation algorithm can calculate a balance around each Model Connector.

Model Connectors also allow you to simplify your flowsheet graphically because you can use them within the same model to feed streams from one physical part of the plant to another part that is graphically widely separated.

Smart constraints

This object permits users to specify additional constraints on a balance envelope.For instance when components should balance, as well as mass or volume balancing.

Smart Constraints use the Smart Object capability which allows you to use formulas that refer to measured or calculated values in other objects in the model and enforce a constraint.

Receipt and Shipment

These objects are like half-nodes because they will either have an input or an output stream, but not both. For instance, a receipt object will have an output stream that flows into the rest of the plant. The material arriving at the plant (say, by pipeline or truck) is not shown as an input. Instead, the Receipt object is treated as the source of the arriving material.

Aside from a name and description neither Receipts nor Shipments have properties. For instance, in the case of a Receipt, the measurement value indicating how much material arrived belongs to the Stream object leading from the Receipt, not to the Receipt object itself.

Because Receipt and Shipment objects do not have both in and out streams, no balance envelope exists around them.

Visual Aids

These objects are ignored by the balancing algorithm but exist on the flowsheet in the GUI to assist the user.

Text

A Text is simply a textual label you may place anywhere on the flowsheet to label or document the flowsheet content.

Navigator

This is a click-able button that will take you to another flowsheet which shows another sub-model (linked to the current one by a Model Connector).

Table

A table is a way of presenting tabular information in the flowsheet. The contents of the table cells are flexible, accommodating hand-entered text, formulas that take input from other cells in the table using syntax similar to Microsoft Excel, values obtained from external data sources, and data taken from the properties of AVEVA Production Accounting objects.

KPI object

The KPI object generates custom data metrics from existing datasets using various expressions. The data metrics help evaluate operational performance.