On June 30, 2014, EPA published the long awaited and much anticipated Petroleum Refinery Sector Proposed Air Rules. For those working as environmental compliance managers in air at petroleum refineries, this rulemaking has been a hot topic ever since the initial residual risk rule came out a number of years ago, and has only heated up. As EPA has issued the general rules on heat exchangers, and issued the Information Collection Request in 2011. Add to that the decision in Sierra Club v. EPA (D.C. Circuit 2008) on the startup, shutdown and malfunction exemption, it was expected that this rulemaking would be comprehensive.
Flares have been a topic of investigation and debate for quite sometime. With the incorporation of flare gas recovery systems and flare minimization plans as part of EPA's petroleum refinery enforcement initiative and state regulatory permitting efforts, the routine operation and maintenance of flares, flare gas systems and fuel gas systems at refineries; the day-to-day management of these control devices have changed. Now, with the proposed rulemaking, more change is anticipated.
Using EPA’s estimates, petroleum refineries currently operate approximately 510 flares of which 285 receive flare vent gas flow on regular basis, the proposed flare requirements will impact all refineries. The bulk of the anticipated capital and annualized costs estimated by EPA are a direct result of the proposed flare requirements.
As a result of the Refinery Enforcement Initiative, and information from studies conducted on flare performance, EPA has determined that the General Provision requirements for flares are inadequate to ensure proper performance of refinery flares. EPA’s assessment identified the following factors that affect flare performance:
1) The flow of the vent gas to the flare;
2) The amount of the assist media (air or steam) added to the flare; and
3) The combustibility of the vent gas/assist media mixture in the combustion zone of the flare.
To address the changes in the flare performance and to ensure the intended combustion efficiency, EPA is proposing numerous changes in the management of refinery flares and is making the changes in the refinery specific rules rather than the General Provisions. The proposed changes include:
Pilot Flames – EPA is amending the current language to include a new operational requirement to use automatic relight systems for all flare pilot flames.
Visible Emissions – EPA is amending the current language to add a requirement that a visible emission test be conducted each day and whenever visible emissions are observed from the flare. Including, a requirement that visible emissions test be performed if the owner/operator is notified by an employee or member of the community of the observance of a visual emission.
Flare Tip Velocity – EPA is proposing that air-assisted flares be required to utilize the same equation as steam-assisted flares to establish a flare tip velocity limit. EPA is proposing to remove the flare tip velocity equation for non-assisted flares with a hydrogen content of greater than 8 percent. Additionally, EPA is proposing to require continuous monitoring to determine the flare tip velocity.
Operating and Monitoring Requirements – EPA is proposing to add definitions relevant to refinery flare performance; “flare vent gas” and “combustion zone gas” and proposing new operational limits, along with methods for determining these limits in the combustion zone at the flare tip to ensure that there is enough combustible material readily available to achieve good combustion. To ensure that the new operating limits are met on a continuous basis, EPA is proposing the installation of continuous monitoring equipment capable of demonstrating compliance on a 15 minute-block average. EPA did provide some information about combustion zone gas monitoring alternatives.
To obtain a copy of the proposed rule making, click here.
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