Control models describe the abatement efficiencies of your entity's control devices. A control device might operate under normal conditions at its peak level or under upset conditions when it is not performing optimally. To account for these different conditions, you can set up multiple control models and indicate the date range during which each control model is effective.
Using one of the following methods, you can specify how a control device is operating:
Define an abatement model for one control device or a class of devices. Abatement information can be obtained from the manufacturer's specifications for the device or stack testing and may consist of the default, and material-specific or material group-specific abatement efficiencies.
Use a control equation (condenser equation) to specify a dynamic abatement efficiency.
Indicate that the control device is shutdown, and its abatement efficiency is zero.
Model control device operations on the Process Unit Control Model form.
For additional instruction on modeling control device operations, click the following links or use the scroll bar to scan the page.
|
On the Abatement Model form, set up models detailing the efficiency at which a control device abates the materials or groups of materials that pass through it. You can define general models or control device-specific models. General abatement models apply to a class of control devices at your entity. Specify this type of model if you have many control devices that abate in the same way. For instance, you could set up a model to describe the abatement of cyclones that were all manufactured by the same company. By contrast, control device-specific abatement models only apply to one individual control device (process unit). For example, this type of model would allow you to account for a control device manufactured by a different company with a separate set of abatement efficiencies.
To set up an abatement model, select the abatement efficiency for individual materials and for material groups. If a material is not included in the individual or material group abatement efficiencies, you can specify a default efficiency to be used for these materials. Because you can specify one, two, or all three types of abatement efficiencies, they are applied to incoming streams in the following order:
If a particular material's abatement efficiency is specified, that abatement efficiency is used.
If a material group abatement efficiency is specified, that abatement efficiency will be used for all materials belonging to that group whose individual abatement efficiency is not defined.
If a material does not have an applicable material or material group abatement efficiency defined, the default efficiency will be used.
You can enter one or more abatement models for a control device to reflect different operating conditions. (Each abatement model should have a unique name.) One model may define the control efficiencies during normal modes of operation, while a second model defines the control efficiencies during upset conditions. The control device is not working optimally during upset conditions, so control efficiencies may be lower. Indicate when each abatement model is operational during a date range on the Process Unit Control Model form.
Control device-specific abatement efficiencies can be tracked over time. Specify the applicable process unit and select the Material Efficiency changes over time option for each material to be tracked. The initial efficiency and subsequent changes are stored as process unit parameter result records. The efficiency percentage is entered as a numeric value along with the percentage units of measure. In order to establish the initial parameter result record, a parameter name record and corresponding process unit parameter definition record are also automatically created when none exist. The name assigned to the parameter is "Abatement Efficiency" followed by a hyphen and the material name, e.g., Abatement Model - Benzene. When a parameter already exists for the efficiency being entered, an option is available to use the existing parameter or enter a new parameter name.
Note:
Parameter-related records are not automatically created for material
groups.
To change an efficiency, specify the effective date/time and new value. Optionally, include a reason for the change, the data origin, and any relevant comments. Designate the efficiency as a potential deviation when applicable and enter deviation details. Refer to Deviation Tracking for additional information. Efficiency changes are compared to the limits set for the parameter in the Value Range fields on the Parameter form. For example, the valid range of pH values is 0 to 14. Results are also compared to any % Variation From Previous Value limits in the Results Settings section on the Parameter Definition form. A message is displayed if a result entered violates a limit. For an invalid parameter value, change the efficiency value to comply with the established limits. For invalid % Variation From Previous Value results, either change the value or enter a comment in the Comments field to save the parameter result record. Refer to Parameter Result Validation Process for additional information.
After the change is saved, the current efficiency is displayed on the Abatement Model form and the change record is added to history. A View History link is available to review the changes made for each material, material group, and default efficiency. History can also be viewed on the Parameter Results View.
To establish abatement models
Click Data
Entry > Emission Model Information > Abatement Models
in the Navigation Tree.
The Abatement Models list appears.
Click the New
button.
The Abatement Model form is
displayed.
Select an Entity from the list.
Enter an abatement Model Name.
Click the General
or Process Unit Specific (control
device) abatement model type and select a process unit from the list
when the Process Unit Specific
option is specified.
If the process unit is not listed, click the Ellipsis
button and add it.
Add information in the Material Abatement and Material Group Abatement sections.
Enter a Default Efficiency. For process unit-specific abatement models, select the Default Efficiency changes over time check box when applicable.
Click the Save button on the form.
Repeat steps 2 through 8 to add other abatement models.
If you know a control device's efficiency for the abatement of specific materials, you can document the efficiency percentages in the Material Abatement section on the Abatement Model form. This efficiency will be applied to all incoming streams and will supersede any material group or default abatement efficiencies that are defined in the model.
Access the Abatement Model list, click the model link to display the Abatement Model form, and expand the Material Abatement section when necessary.
Click Add Material and select a Material from the list.
Follow the guidelines below to specify the efficiency:
For general abatement model materials, enter the Efficiency for the material and click OK. The material information is displayed as a line item in the Material Abatement section. Click the material link to access the material record. Edit existing material information using the buttons adjacent to the line item. Skip to step 9.
For process unit-specific abatement model materials without efficiency changes over time, enter the Efficiency for the material and click OK. The material information is displayed as a line item in the Material Abatement section. Click the material link to access the material record. Edit existing material information using the buttons adjacent to the line item. Skip to step 9.
For process unit-specific abatement model materials with efficiency changes, select the Material Efficiency changes over time check box and click OK to open a separate window for entering the initial efficiency. Continue to step 4.
Note: If a parameter already
exists for the efficiency being entered, a pop-up window is displayed
to either accept the existing parameter (default) or enter a new parameter
name. Click OK to continue.
Enter the Date/Time of the change. The Calendar button is available to select the date.
Enter the Efficiency and any related Comments.
Click the Potential
Deviation check box when applicable.
The Track Deviations button
is displayed and provides access to the Deviation
Details form. Refer to Deviation
Tracking for additional information.
Select a Reason
for Change and/or Data Origin
from the list for each field.
If the appropriate value is not listed, click the Ellipsis
button next to the field and add it.
Click Save.
The material information is displayed as a line item in the Material
Abatement section. Edit existing material information using
the buttons adjacent to the line item. Click the material link to
access the material record.
Repeat steps 2 through 8 to add other material abatement efficiencies.
Click the Save button on the Abatement Model form.
In the Material Group Abatement section on the Abatement Model form, you can specify the efficiency at which a control device abates a class of materials, such as VOCs. This feature is useful because often a control device's ability to abate individual materials is not known, or various materials that have similar properties might pass through the control device at different intervals. In these cases, it is easier to specify the abatement of a group or class of materials instead. For instance, a facility might have a control device installed that abates emissions from a paint booth. During production, the facility might use different paints in the paint booth. Instead of defining a model for each volatile organic compound, the entity can assign all the paints and/or their components to a material group, "VOC", and then specify just the efficiency of the group.
To add abatement efficiencies
for material groups
Access the Abatement Model list, click the model link to display the Abatement Model form, and expand the Material Group Abatement section when necessary.
Click Add Material Group.
Select a Material
Group from the list.
If the group is not listed, click the Ellipsis
button and add it.
Enter the Efficiency
for the material group and click OK.
The material group information is displayed as a line item in the Material Group Abatement section.
Edit existing material group information using the buttons adjacent
to the line item. Click the material group link to access the material
group record.
Repeat steps 2 through 4 to add other material group abatement efficiencies.
Click the Save button on the form.
Control device-specific material, material group, and default abatement efficiencies can be tracked over time on the Abatement Model form. Click the Change Efficiency link, specify the new efficiency value, and assign an effective date/time. Include a reason for the change, the data origin, and any relevant comments. Designate the efficiency as a potential deviation when applicable and enter deviation details. Refer to Deviation Tracking for additional information. When the change is saved, the current efficiency is displayed on the Abatement Model form and the change record is added to history.
For materials and material groups, the Change All Material Efficiencies option and the Change All Material Group Efficiencies option are available to enter a new efficiency for multiple materials/material groups at one time. The date and time entered will be assigned to each efficiency that is updated.
A history of the abatement efficiency changes made for each material, material group, and the default value is available for viewing. Click the View History link. Each change is displayed as a line item. Click the Edit button adjacent to the line item to view the change record.
Note:
The View History links and
the links for changing abatement efficiencies are available only when
the material/material group/default efficiency has been flagged to track
changes over time. Otherwise, the links are not displayed.
To change individual abatement
efficiencies
Access the Abatement Model list, click the model link to display the Abatement Model form, and expand the Material Abatement, Material Group Abatement, or Default Efficiency section when necessary.
Click Change Efficiency for the material, group, or default value to be updated.
Enter the Date/Time of the change. The Calendar button is available to select the date.
Enter the new Efficiency and any related Comments.
Click the Potential
Deviation check box when applicable.
The Track Deviations button
is displayed and provides access to the Deviation
Details form. Refer to Deviation
Tracking for additional information.
Select a Reason
for Change and/or Data Origin
from the list for each field.
If the appropriate value is not listed, click the Ellipsis
button next to the field and add it.
Click Save.
The new efficiency is displayed on the Abatement
Model form. Should the record require edits, click View
History and click the Edit
button adjacent to the change record line item to open it.
To change all material or
all material group efficiencies.
Access the Abatement Model list, click the model link to display the Abatement Model form, and expand the Material Abatement or Material Group Abatement section when necessary.
Click Change
All Material Efficiencies or Change
All Material Group Efficiencies.
Each material/material group is displayed as a line item. One or more
efficiency record can be updated.
Enter the Date/Time
of the change. The Calendar
button is available to select the date.
The date and time entered applies to all efficiencies updated during
this change process.
Enter the new Efficiency and any related Comments.
Click the Potential Deviation check box when applicable. Refer to Deviation Tracking for additional information.
Select a Reason for Change and/or Data Origin from the list for each field.
Click Save.
The new efficiency is displayed on the Abatement
Model form. Should any of the updated efficiency records require
edits, click View History
and click the Edit button
adjacent to the change record line item to open it.
On the Process Unit Control Models form, you can set up control models to indicate how the control devices at your entity are operating over a time period. Control models can indicate the normal operation of the control device, upset conditions during which the equipment is not working optimally, or a shutdown. In this way, you can account for different operating scenarios and accurately predict emissions.
For each control device at your entity, select one of three options for modeling its abatement efficiency. Enter the date range during which the model is effective; if you do not enter an end date, then the model will always be effective. The options available are:
None—emissions that pass through the control device are not abated, so the control efficiency is zero.
Abatement model—model that determines the control device's default abatement efficiency and its efficiency for abating individual materials or material groups. Set up this model on the Abatement Model form.
Condenser equation—uses the outlet temperature and incoming stream temperature to determine a dynamic abatement efficiency.
Once you have determined which control method to use, you must identify the process units to which the control device is linked. These process units can be other control devices or emission points through which the controlled or abated streams will pass.
To establish control models
Click Data
Entry > Emission Model Information > Process Unit Control Models
in the Navigation Tree.
The Process Unit Control Models
list appears.
Click the New
button.
The Process Unit Control Model
form is displayed.
Select an Entity
from the list.
If the appropriate entity is not listed, click the Ellipsis
button and add it.
Select a Process
Unit from the list.
If the applicable process unit is not listed, click the Ellipsis
button and add it.
Enter an Effective Date and Shutdown Date for the model or use the Calendar buttons to select the dates. If the Shutdown Date field is left blank, the model will always be effective.
Select a Control Method from list. Model details cannot be specified when "None" is selected as the control method.
Add information in the Model Details and Abatement Links sections.
Click the Save button on the form.
Repeat steps 2 through 8 to add other control models.
In the Model Details section on the Process Unit Control Model form, define the control device's modeling details for the abatement model and control equation control methods as follows:
For the Abatement Model control method, select the appropriate model. The abatement model assigns the default, material-specific, or material group-specific abatement efficiencies to the control device.
For the Control Equation control method, select the appropriate equation. (Only the condenser equation is available.) The condenser equation allows you to use the incoming stream temperature and the condenser temperature to determine a dynamic abatement efficiency for the control device. The incoming stream temperature is entered on the Process Unit Emission Model form for the process units that are linked to the control device.
Note:
If "None" is selected as the control method, the Model Details section will be unavailable
for data entry.
To enter control model details
Locate the control model, click the link to display the Process Unit Control Model form, and expand the Model Details section when necessary.
Use the following guidelines to specify control method details:
For the Abatement Model control method, select an Abatement Model from the list. If the appropriate value is not listed, click the Ellipsis button and add it.
For the Control Equation control method, select the Control Equation from the list, enter the Condenser Temperature and select a corresponding Unit of measure from the list. If the appropriate unit is not listed, click the Ellipsis button and add it.
Click Save.
In the Abatement Links section on the Process Unit Control Model form, select the process units to which a control device vents the controlled and abated emission streams passing out of it. For instance, an emission stream could be directed to a condenser that is used for solvent recovery before it goes to a flare.
Although a control device may be physically linked to a number of other process units in your entity, you should select only the process units to which the control device is linked during the effective date of the model. The entries on the Process Unit Link form determine to which process unit the controlled emission stream is directed and to which process unit the abated stream is directed.
Note:
Only the process units to which you specified the control device
vents on the Process Unit Link
form will be available. Additionally, you can only specify that controlled
and abated streams pass out of the control device, not generated ones.
To assign control model
links
Locate the control model, click the link to display the Process Unit Control Model form, and expand the Abatement Links section when necessary.
Select the Available
Process Unit Links and click the right arrow button to include
them in the Applicable Process Unit
Links field.
Click Edit Process Units Links
to add other process unit links to the list of Available
Process Unit Links. To remove an Applicable
Process Unit Link, select it and click the left arrow button.
Click Save.
