BOARD MEETING DATE: September 3, 2004
AGENDA NO. 33

Receive Evaluation Report on Emissions from Flaring Operations at Refineries and Direct Staff to Initiate Amendment of Rule 1118

SYNOPSIS:

As part of the February 13, 1998 Rule 1118 adoption resolution, the Governing Board directed staff to evaluate all the information and data collected and submitted to the AQMD by the affected facilities subject to Rule 1118 – Emissions from Refinery Flares. The report provides an analysis of the information obtained in the first four years from the start of monitoring and recording of flaring operations to determine whether or not emissions from flaring operations are significant, and makes recommendations for the Board’s consideration on changes to Rule 1118.

COMMITTEE:

Stationary Source, August 27, 2004

RECOMMENDED ACTION:

Receive the attached report and direct staff to initiate amendment of Rule 1118 based on the Evaluation Report on Emissions from Flaring Operations at Refineries.

Barry R. Wallerstein, D.Env.
Executive Officer

Background

On February 13, 1998, the Board adopted Rule 1118 – Emissions from Refinery Flares. The purpose of this rule is to monitor the quantity and composition of gases flared at petroleum refinery operations in order to improve the flare emission inventory and to assess the need for, and/or the level of, any future controls required to minimize flare emissions.

As a part of the February 13, 1998 Rule 1118 adoption resolution, the Board directed staff to evaluate all the information and data collected and submitted to the AQMD by the affected facilities subject to Rule 1118, and based on all such information obtained in the first two years from the start of monitoring and recording of flaring operation:

• Make a determination on whether emissions from flaring operations are significant; and
   
• Make recommendation for the AQMD Governing Board’s consideration of any changes to Rule 1118.

Facilities subject to this rule are petroleum refineries, sulfur recovery plants that recover sulfur compounds from sour water generated by petroleum refineries, and hydrogen production plants that produce hydrogen from refinery gas and supply hydrogen for petroleum refinery operations that operate a gas flare. Flare use varies from facility to facility. The gas flares are used for the combustion and disposal of combustible gases due to emergency relief, overpressure, process upsets, startups, shutdowns and other operational and safety reasons. During this evaluation period, twenty-seven flares at ten facilities were subject to this rule. These ten facilities included eight refineries, one sulfur recovery plant and one hydrogen production plant.

During 2002 and 2004, AQMD staff met with each of the refineries and sulfur recovery plant subject to Rule 1118 – Emissions from Refinery Flares, to clarify data collected for the past four years and address additional questions staff had. Facilities subject to Rule 1118 are:

• BP West Coast Products (Refinery)
• Chevron Products Company (Refinery)
• Equilon Enterprises, LLC, Shell Oil Products U.S. (Los Angeles Refinery)
• Equilon Enterprises, LLC, Shell Oil Products U.S. (Sulfur Recovery Plant)
• ExxonMobil Oil Corporation (Refinery)
• Paramount Petroleum Corporation (Refinery)
• ConocoPhillips Company (Refinery – Carson Plant)
• ConocoPhillips Company (Refinery – Wilmington Plant)
• Ultramar Inc. (Refinery)
• Air Products (Hydrogen Production Plant)

Conclusion and Recommendations

The emissions data from October 1, 1999 through December 31, 2003, and the additional information collected during the meetings was examined to determine the amount of emissions due to flaring within the Basin. This process was complicated by the failure of some facilities to fully comply with Rule 1118 and the almost total failure of one facility to do so. Based on the analysis of the reported emissions and accounting for failures to comply with the rule, staff has determined that flare operations represent a significant emissions source, especially SOx emissions, which accounted for 54 percent of SOx emissions from other sources at the refineries in 2000, 43 percent in 2001, 22 percent in 2002, and 23 percent in 2003, respectively. Summary of flare emissions data reported for the years 2000 through 2003 are shown in the table below. It should be noted that the refineries have reported significant reductions in emissions from flares during the past two years, citing increased operation awareness and facility best management practice.

Overview of Flare Emissions As Reported Pursuant to Rule 1118
 

¹ 3 rd and 4 th Quarter 2003 AER emissions were estimated since fiscal year 2003-2004 AER reports were not due as of the writing of this report

Note: For year 2001, one facility indicated that they over reported the flare emissions as a result of the flow meter being out of commission for 20 days. As a result, this facility used the maximum design capacity of the flares during the 20-day period. They subsequently provided revised data estimating emissions based on process parameters. If the estimated emissions provided by the facility were to be used, the overall emissions would be as follows for 2001:
 

However, since the method used to estimate the emissions during the 20-day period has not been demonstrated to be adequately accurate to the satisfaction of AQMD staff and was not used to report the Rule 1118 quarterly emissions, the data presented in this report continues to use maximum design values as reported under the Rule 1118 requirements.
 

Although SOx emissions from refinery flares can be significant, currently there are no AQMD rules establishing emissions limits from refinery flares. Also, existing federal rules either do not apply to most flares, or in cases where they do apply, limits are difficult to enforce and do not guarantee emission reductions.

Although efforts have been made by many facilities to minimize flare emissions since the start of the program, there are further emission reduction opportunities and emission reduction targets that should be explored by facilities subject to Rule 1118. Several control options were evaluated to determine the feasibility of reducing flare emissions. One or more of the following methods have been employed by refineries in the Basin to a certain extent to reduce flare emissions. However, there is no regulatory requirement to ensure that emission reductions will continue. Staff recommends that Rule 1118 be amended to set appropriate emission goals for facilities subject to the rule. Taking into account the unique operational requirements and the current flare emission levels at each facility, one or more of the following emission reduction methodologies below may be considered by each facility to further minimize emissions and meet the emission reduction goals appropriate for each facility:

• Prevent flaring of refinery fuel gas, process gas from leaking valves, and non-emergency flare events (excluding planned startups, shutdowns and turnaround activities). Methods that have been employed to minimize flaring and reduce emissions include:

Installing a vapor recovery system at a facility without existing
       vapor recovery capability;

Increasing the vapor recovery system capacity;

Increasing the fuel gas treating system capacity; and

Implementing routine inspection and monitoring to detect
       leaking valves.

• Minimize the duration and volume of gas vented to the flares due to emergencies, planned startups and shutdowns, and turnaround activities. This may be accomplished by:

Improving operational and maintenance procedures to prevent
       upset conditions; and

Improving gas minimization plans for startups, shutdowns, and
       turnaround activities.

Several methods for post combustion treatment of emissions have been analyzed preliminarily but were not deemed practical for refinery flares due to the elevated configuration of the existing flaring equipment and the intermittent nature of their operation.

In addition to setting emission reduction targets, staff recommends Rule 1118 be amended to increase compliance and the accuracy of emissions information. In reviewing the flare emission data during this evaluation, staff has also determined that steps are necessary to increase both rule and plan compliance. Also, further refinements to the monitoring, reporting and emission calculation methodology would increase the accuracy of emissions information. The refinements that could be further explored during future rule development efforts include:

• Installation of additional flow meters or equipment capable of accurately measuring vent gas flow at low flow rates. This additional provision should allow for accurate flow measurements across the full flow range of the flares and allow for detection of continuous flaring of gas at low flow due to leaking valves.
   
• Installation of continuous gas monitoring systems such as gas chromatography equipment to measure and record H₂S and Total Reduced Sulfur (TRS) concentrations and Higher Heating Value (HHV) continuously for each flare.
   
• Enhancement of standard methodologies for flow and emission calculations.
   
• Establishment of standardized substituted data procedures when actual data are not available through direct measurements.

As a result of review of Rule 1118 data to date, and the emission reduction opportunities available, staff recommends rule amendment activities commence immediately to initiate the public process to amend the rule requirements.

Attachment

Evaluation Report on Emissions from Flaring Operations at Refineries

/ / /