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December 19, 1995 Proposal Submission

CITGO Petroleum Corporation

Corpus Christi Refinery

P.O. Box 9176
1801 Nueces Bay Blvd. PH - 512-844-4000
Corpus Christi, Texas 78469-0321 FAX - 512 844-5108

December 19, 1995

P 373 571 926

Regulatory Reinventing Pilot Project
Water Docket
U.S. Environmental Protection Agency
Mail Code 4101
401 M Street, S.W.
Washington, D.C. 20460

Attention: Water Docket

CITGO is pleased to offer our proposal under the XL program. We believe that this project holds promise in demonstrating that fired source emissions can be effectively monitored and controlled at the CITGO Corpus Christi Refinery. This proposal has not been offered as a Common Sense Initiative project.

Our application includes a short description and a matrix demonstrating showing how Project XL criteria will be met. We continue to solicit local and state government support for this project, and could use your help in gaining the support of Region VI. Requested letters for support from the Texas Natural Resource Conservation Commission (TNRCC) and EPA Region VI are enclosed. Progress reports will be supplied to all stakeholders on a regular basis.

The "cleaner" part of the project is that by using computer models we are able to determine what influences NOx and CO production from a unique source. From our preliminary work these process variables are not always the same, but vary from source to source. It is evident that once a set of variables are identified they can be manipulated to minimize the formation of the undesired emissions. It also follows that for any set of sources a computer optimization can be developed to produce minimum emissions for each process operational scenario. This will assure that fired sources in the refinery will be producing the lowest emission for any set of circumstances.

We have conducted tests of software CEM, and have gained some experience. Phase I of our project will consist of hooking up two boilers to predict NOx emissions. Comparisons will be made between modeled boiler emissions and measured values. Experience will also be gained in adjusting boiler firing parameters in order to lower emissions. Phase II will involve developing a computer program to optimize boiler firing while minimizing NOx production. We anticipate the first two phases to take 6 to 12 months to complete. After this the concept will be extended to encompass CO emissions also. Eventually, we envision these emission control/optimizers to be

Water Docket

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December 19, 1995

an integral part of the entire refinery control scheme, thus maximizing unit operations while minimizing NOx and CO formation. CITGO proposes that emission caps be provided facility wide for us to realize the total benefit from this project. We anticipate this to be a negotiated limit based on the equipment in place and any future modifications to the facility. Of course, recordkeeping and reporting requirements would be an integral part of this agreement.

Secondly, as part of the PSD program CITGO will be required to install a ground level NOx monitor to demonstrate that the NASA for NOx is not exceeded. This is a very costly and time consuming exercise. We propose that the results from the models be used to demonstrate that emissions are better controlled so that ground level monitoring devices would not be needed.

CITGO has long maintained that government/industry partnerships such as proposed by this project are far preferable to command and control regulations. We look forward to working with the EPA, the Texas Natural Resource Conservation Commission, and local government who are interested in achieving the goals of the XL Program. Additionally, since the Corpus Christi area is a "ozone non-attainment area", minimizing NOx, an ozone precursor, will have a positive impact on the governmental entities efforts to maintain the attainment of the area.

We propose that EPA furnish a person experienced in computer modeling to work with us in verifying project results. We are also hopeful that the TNRCC will supply a person to work on this project.

We look forward to this partnership with the agency to accomplish this project in as short a time as possible. If you should require additional information, please contact me at (512) 844-4100. Thank you for your consideration, and we would appreciate it if you would notify us if our proposal is accepted.


Philip Vrazel

Manager of Environmental Affairs



Proposed Project XL


Objective: To demonstrate that Parametric Models can be utilized to cost effectively monitor NOx and CO emissions from fired sources in a refinery to comply with monitoring requirements of the 1990 Clean Air Act Amendments. To demonstrate that combustion pollutants can be optimized when these models are tied to refinery operating systems through neural network technology.

Background: Title V of the 1990 Clean Air Act Amendments require emission monitoring to verify a facility's "continuous" compliance with applicable emission limits. In October 1993, EPA proposed a rule that mandates continuous, instrumented emission monitoring (CEM) The rule is presently undergoing change. Continuous parametric emission monitoring (PEM) or centralized multi-point instrument analysis are less elaborate but equally satisfactory monitoring methods. An even more flexible approach would be to allow the marketplace to develop innovative monitoring systems. Emission control and optimization possibilities are not addressed by traditional CEMs, because they simply gather data. PEMs on the other hand could actually lead to emission reductions and improvements in air quality.

Scope of Work: Parametric models will be developed to demonstrate a reliable alternative to instrumented emission monitors. Neural network mathematical models will be developed not only to predict NOx and CO emissions from fired sources such as heaters and boilers, but also to provide tools that can be used to optimize and/or minimize total facility emissions of combustion pollutants. The project will begin by fully adapting neural network technology to one boiler. If the pilot project is successful, all fired sources within the refinery will be tied into the system. Operational and modification flexibility will be provided through a refinery-wide emissions cap. A streamlined recordkeeping and reporting system, as well as an inspection procedure will be developed.

Potential Benefits/Obstacles: The project will be "cleaner" because emissions will be reduced, "cheaper" because PEMs are less expensive than CEMs, and "smarter" because it allows more efficient use of industry and government resources. Parametric measurements tied to proper validation techniques are more reliable than CEMs. NOx and CO emissions can be optimized on a facility-wide basis and still demonstrate compliance with the facility's total permitted emissions. PEM technology costs less than CEM expenses. For a medium sized refinery with average existing controls, this could save capital expenditures of $10-15MM. This technology can be transferred to any manufacturing process using fired sources. Advantages of operational and modification flexibility and improved compliance controls can be demonstrated. Technical complexity, while presenting challenges for this project, will be thoroughly explained to stakeholders. Indications that this technology will work are promising.

Enforcement Concerns/Requirements: Validation procedures could become as onerous as CEMs. Automated reporting will be provided. Inspection and enforcement systems should be adequate to satisfy regulatory concerns.

Project XL

Project Selection Criteria: AND CANDIDATE PROJECT

Project Selection Criteria:
Environmental Results
How is the Criterion Addressed by the Candidate Project?
Achieves "cleaner results" - PEM software tied to operating controls will allow quick and cost effective controls of NOx emissions, a precursor to ozone, thereby minimizing ozone formation. Continuous compliance assurance will be equal to that provided by monitoring instruments. PEM software will immediately indicate if emission limits are exceeded. Improved fired source monitoring and control will result.

Project Selection Criteria:
Reduces costs and paperwork burden
How is the Criterion Addressed by the Candidate Project?
Cost/benefit analysis of the approach should be positive. Continuous emission monitors could cost as much as $250,000 per source; whereas parametric emission monitoring (PEM) software and related equipment may cost $50,000. Emission control maintenance costs are also reduced. Automated reports will reduce paperwork burdens.

Project Selection Criteria:
Stakeholder support
How is the Criterion Addressed by the Candidate Project?
All stakeholders are concerned about air quality near refineries and manufacturing plants. Corpus Christi is currently in "near non-attainment" for ozone. All stakeholders will gain if stack emissions from heaters and boilers are controlled and reduced.

Project Selection Criteria:
Innovative/multi-media pollution prevention
How is the Criterion Addressed by the Candidate Project?
How is the Criterion Addressed by the Candidate Project?
This project will encourage development and commercialization of additional innovative emission monitoring approaches and technology. CEM computer programs that utilize Neural Network technology are already available.

Project Selection Criteria:
How is the Criterion Addressed by the Candidate Project?
This technology can be used for fired source control at many manufacturing plants in other industrial sectors, thereby having broad industry applicability.

Project Selection Criteria:
Project feasibility
How is the Criterion Addressed by the Candidate Project?
Pilot study results indicate a very good chance for success. Benefits should be realized within nine months, and as the project expands additional benefits will accrue.

Project Selection Criteria:
Monitoring, reporting and evaluation
How is the Criterion Addressed by the Candidate Project?
Summary reports on a monthly basis will enable stakeholders to understand project status. Quantitative emissions data will be provided.

Project Selection Criteria:
Shifting of risk burden
How is the Criterion Addressed by the Candidate Project?
Worker safety will be ensured throughout the project and no one will be subject to disproportionate impacts.

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