WARalgorithm Class

public class WARalgorithm : Form

Public Class WARalgorithm
	Inherits Form

Inheritance

Object    MarshalByRefObject    Component    Control    ScrollableControl    ContainerControl    Form    WARalgorithm

The WAR plug-in works by directly access the unit operations and material flows within the flowsheet. Once the WAR plug-in has been instantiated by the flowsheeting environment, in this case, COFE, the WAR plug-in is initialized and provided with a reference to the flowsheet monitoring interface enabling the plug-in to directly access the flowsheet’s unit operation and stream collections. The flowsheet monitoring interface is one of the features of the simulation context provided by COFE to the WAR plug-in.

Upon activation, the WAR plug-in enumerates all of the unit operations and streams contained within the flowsheet using the flowsheet monitoring interface. First, the plug-in places references to the streams in two stream collections, separate input and output stream collections. The unit operations in the unit operation collection are queried for inlet and outlet ports. The streams connected to these ports are matched against the streams in the input and/or output stream collections. Streams that are attached to input ports for a unit operation are then removed from the output stream collections as the no longer leave the process. Likewise, streams that are attached to an outlet port are removed from the input stream collection as they originate within the process. That is, streams not connected to any unit operation outlet port are considered feed streams, and streams that are not connected to any unit operation inlet port are considered output streams. An exception to this rule is that some PMEs utilize “source” unit operations that only have a single outlet stream and no inlet streams. These units are considered to be feed units, and the stream connected to it is considered to be a feed stream. Analogously, unit operations that have only a single inlet port and no outlet ports are considered to be product units; the streams connected to it are considered to be product streams.

This plug-in also allows users to select only portions of the flowsheet for a WAR analysis. This is accomplished by having the user select the unit operations of interest. The feed and product stream algorithms for a sub-set of the total unit operation collection are similar to the algorithm described above for the total flowsheet.

Once the feed and product streams have been identified, the plug-in performs its WAR calculation. The specific PEI, ψ_(k,i)^S, for each chemical is calculated by averaging the impact category scores for all the chemicals in the database and normalizing by dividing the chemical’s score by the average value. Once the normalized ψ_(k,i)^S has been calculated, the PEI generated by the process, İ_gen, is calculated using the normalized value of ψ_(k,i)^S for the individual categories, category weighting factor mass flow rates and the concentration of the chemical of each stream. The plug-in allows the user to designate product streams and account for energy usage in the WAR algorithm.

Reference