Please see Reporting Form Instructions on downloading the blank reporting form and uploading the completed reporting form.
You may also refer to Optional Calculation Spreadsheet Instructions to download the Subpart W calculation spreadsheet.

This page provides an overview of the Subpart W dehydrators source category e-GGRT reporting requirements.

The dehydrators source category is applicable to Onshore Petroleum and Natural Gas Production and Onshore Natural Gas Processing.

Indicate if the facility has the source type via the radio buttons.

• If the source type is present you must report required emissions.

If the facility has the source type, the Best Available Monitoring Methods and Missing Data table must be completed.

• For further information, see Best Available Monitoring Methods and Missing Data Reporting.

Reporting Requirements

For all glycol dehydrators with an annual average daily throughput less than 0.4 MMscfd, the facility is required to report:

• What vent gas controls are used? ((98.236(c)(4)(ii)(B))
  • Vapor Recovery
  • Dehydrator Vents to Flares
  • Regenerator fire-box/fire-tubes
  • No vent controls
  • Other or Multiple Vent Gas controls. For this row also provide description in "Describe "Other" gas vent controls" column.
• Annual total CO₂ emissions at the facility level that resulted from venting gas directly to the atmosphere combined for all glycol dehydrators for each vent control category with annual average daily throughput less than 0.4MMscfd (98.236(c)(4)(ii)(C)). Do not include those amounts which have been captured or recovered and are not vented to the atmosphere.
• Annual total CH₄ emissions at the facility level that resulted from venting gas directly to the atmosphere combined for all glycol dehydrators for each vent control category with annual average daily throughput less than 0.4MMscfd (98.236(c)(4)(ii)(C)). Do not include those amounts which have been captured or recovered and are not vented to the atmosphere.
• Annual total CO₂ emissions at the facility level that resulted from the flaring of process gas combined for all glycol dehydrators for each vent control category with annual average daily throughput less than 0.4MMscfd (98.236(c)(4)(ii)(D))
• Annual total CH₄ emissions at the facility level that resulted from the flaring of process gas combined for all glycol dehydrators for each vent control category with annual average daily throughput less than 0.4MMscfd (98.236(c)(4)(ii)(D))
• Annual total N₂O emissions at the facility level that resulted from the flaring of process gas combined for all glycol dehydrators for each vent control category with annual average daily throughput less than 0.4MMscfd (98.236(c)(4)(ii)(D))
• Count of Glycol Dehydrators (W-5) (98.236(c)(4)(ii)(A))

For all absorbent desiccant dehydrators, the facility is required to report:

• Total Count of Absorbent Desiccant Dehydrators (98.236(c)(4)(iii)(A))
• Annual total CO₂ emissions at the facility level for all absorbent desiccant dehydrators combined (98.236(c)(4)(iii)(B))
• Annual total CH₄ emissions at the facility level for all absorbent desiccant dehydrators combined (98.236(c)(4)(iii)(B))

For each glycol dehydrator with a throughput greater than or equal to 0.4 MMscfd, the facility is required to report:

• Unit ID or Name, this is only required if the facility is reporting under the Onshore Natural Gas Processing industry segment
• What vent gas controls are used? (98.236(c)(4)(i)(I))
  • Vapor Recovery
  • Dehydrator Vents to Flares
  • Regenerator fire-box/fire-tubes
  • Other - Report other if control type is not listed or multiple control types are used.  Provide description in "Describe "Other" gas vent controls" column.
  • No vent controls
• Annual CO₂ emissions that resulted from venting gas directly to the atmosphere (98.236(c)(4)(i)(J)). Do not include those amounts which have been captured or recovered and are not vented to the atmosphere.
• Annual CH₄ emissions that resulted from venting gas directly to the atmosphere (98.236(c)(4)(i)(J)). Do not include those amounts which have been captured or recovered and are not vented to the atmosphere.
• Annual CO₂ emissions that resulted from flaring process gas from the dehydrator (98.236(c)(4)(i)(K))
• Annual CH₄ emissions that resulted from flaring process gas from the dehydrator (98.236(c)(4)(i)(K))
• Annual N₂O emissions that resulted from flaring process gas from the dehydrator (98.236(c)(4)(i)(K))
• Glycol dehydrator feed natural gas flow rate determined by engineering estimate based on best available data (MMscfd) (98.236(c)(4)(i)(A))
• Glycol dehydrator absorbent circulation pump type (98.236(c)(4)(i)(B))
  • Natural Gas Pneumatic
  • Air pneumatic
  • Electric
  • Electric/Pneumatic
• Report whether stripper gas is used in glycol dehydrator (98.236(c)(4)(i)(C))
  • Yes
  • No
• Report whether a flash tank separator is used in glycol dehydrator (98.236(c)(4)(i)(D))
  • Yes
  • No
• Report type of absorbent used (98.236(c)(4)(i)(E))
  • Triethylene glycol (TEG)
  • Diethylene glycol (DEG)
  • Ethylene glycol (EG)
• Total time the glycol dehydrator is operating (hours) (98.236(c)(4)(i)(F))
• Temperature of the wet natural gas (degrees Fahrenheit) (98.236(c)(4)(i)(G))
• Pressure of the wet natural gas (psig) (98.236(c)(4)(i)(G))
• Concentration of CO₂ in wet natural gas (mole fraction) (98.236(c)(4)(i)(H))
• Concentration of CH₄ in wet natural gas (mole fraction) (98.236(c)(4)(i)(H))

Total Emissions

The total emissions roll-up at the top of the sheet reflects the sum of the CO₂ equivalents of each gas emission reported for the source type.  These summations are reflected and aggregated on the Introduction tab.