Hydrocarbon Engineering

ProMax

Process Simulation Software

Process Insight

Air Emissions Modeling Advances for

Oil and Gas Production Facilities

perfect storm

has dramatically changed the way oil

and gas production facilities are designed and permitted for air

quality compliance.

Air quality regulations have been strengthened due to

rule changes in the Clean Air Act (40 CFR 60, Subpart OOOO),

drastically reducing the allowed emissions of VOCs from well

sites. These changes were made along with new regulations

of Green House Gas emissions (40 CFR 98, Subpart W). Due

to the more stringent and complex permitting regime, it is now

important to accurately predict VOC emissions rates from oil

and condensate tanks. More complex well site designs which

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compressors are now commonplace. This calls for design-class

process simulation tools.

Along with more stringent rules, the shale revolution

has caused the number of wells drilled in the US to sky-rocket.

Each of these new wells requires a permit with emissions

estimates, dramatically increasing the work load for compliance.

Along with the calculation requirements for permits, annual

inventory reports are also required for a variety of emissions

sources and contaminants. Examples include Greenhouse Gas

Emissions, Flashing Losses, as well as Working, Breathing, and

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programs are therefore necessary to keep up with changes to

calculation requirements.

Well Site Air Emissions – a Brief History

Until recently, well head or compressor station

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typically vented to the atmosphere. (See Figure 1)

With the new regulations, a comparable well is now

equipped with additional features designed to mitigate,

recover, or convert VOC’s in gases that were previously

vented. Designs similar to Figure 2, in conjunction with a

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emissions. To achieve such designs, a high-quality process

simulator like ProMax is necessary for evaluating and

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Another result of this more rigorous air permitting

environment is closer coordination between well site

facility design, air permitting, and air quality compliance

personnel. Air quality parameters are considered in

early design phases and now typically drive the design

process. The resulting process simulation is then used by

air permitting and compliance functions throughout the

life of the well. Use of a design-class process simulation

tool helps bring the work of these two groups together in

seamless fashion.

ProMax brings these new and necessary capabilities

to the design, permitting, and compliance teams.

Additionally, an EPAAP-42 Working, Breathing, and

Loading Loss calculation tool has been added to ProMax so

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ProMax enables compliance teams to run hundreds- even

thousands- of well site inventory calculations in a fraction

of the time and with greater accuracy than was ever possible

before!

For more information about this study, see the full article at

www.bre.com/support/technicalarticles

ProMax® process simulation software by Bryan Research & Engineering, LLC

Engineering Solutions for the Oil, Gas, Refining & Chemical Industries