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Texas A&M Central Utility Plant Site Visit Report
Thursday, November 13, 2014
Prepared by: Elora Arana, Environmental Studies student
Prepared for: Dr. Heather Wilkinson, Professor – BESC 489/411
Texas A&M Central Utility Plant
Texas A&M University, 222 Ireland St College Station, TX 77840
Background and Introduction
The BESC Environmental Health, Safety and Compliance class traveled to the Texas A&M
Central Utility Plant on Thursday, November 13, 2014 under the supervision of Dr. Heather
Wilkinson to examine Texas A&M University’s combined heat and power utilities facility. The
facility is primarily used for generation of heating, ventilation and air conditioning (HVAC) for
the Texas A&M campus, as well as general electricity generation. The facility utilized a fairly
new combined heat and power system that is powered by natural gas, steam and turbines to
offer heat, air conditioning and electricity to the entire campus. This new system is 70‐80%
efficient, compared to typical off‐site fossil fuel power plants which usually run at around 30%
efficiency. This systems helps the Texas A&M campus reduce energy consumption and cost, as
well as significantly reduces their emissions and carbon footprint, and is able to supply the
campus with power during power outages and interruption from the ERCOT grid (Petersen
2014).
Texas A&M Utility and Energy Services serves the entire Texas A&M campus, including
the Riverside campus and consists of four total utility plants: the central plant and three
substations; located near Reed Arena on West Campus, south of the Military Sciences building
on main campus and near the Animal Hospital north of main campus. All four facilities generate
55,000 tons of cooling capacity, 450,000 million Btu/hr heating hot water capacity, 440,000 pph
steam production capacity, and 50 MW power generation capacity coming from a 33 MW gas
turbine driven generator and 17 MW coming from two‐steam turbine driven generators.
Utilities and Energy Services is able to service a 75 MW peak campus load.
Figure 1 provides a diagram of the facility, detailing the placement of critical parts of the
combined heat and power (CHP) system, including boilers, generators, heat exchangers and
chillers. The majority of the equipment was found inside of the central utility building, while
Heat Recovery Steam Generator (HRSG) and supporting components were built outside of the
building as the newest additions to the facility.
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Figure 1 – Diagram of the Texas A&M Central Utility Plant provided by Petersen during the
introduction to the visit.
Figure 2 provides an overview of this facility’s CHP operating process. 600
pounds/square inch (psi) natural gas that is supplied by Atmos Energy via pipeline feeds the GE
LM2500+G4 gas turbine that powers the Brush generator which produces up to 34 MW of
energy. The generator sends 12.47 kV of electricity to electric motor‐driven chillers, which are
used to cool campus facilities, campus facilities for electricity, or to transformers that send it
back to the ERCOT grid. The initial GE gas turbine also produces 950 degree Fahrenheit “waste,”
or exhaust, gas. The HRSG uses this exhaust gas, as well as reverse osmosis water and LP
natural gas for supplemental firing, to produce 600 psi HP steam which is used to drive steam
turbine‐driven chillers for cooling campus facilities, or sent to the Dresser‐Rand Steam Turbine.
This turbine creates 60 psi extraction steam for campus facilities, 20 psi LP steam sent to heat
exchangers used for heating of campus facilities, and powers the Hyundai Ideal 11 MW
generator that produces additional electricity for campus. Without the HRSG, the 950 degree
Fahrenheit “waste” gas would be lost in production and amount to millions of dollars of wasted
product a year.
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Figure 2 – The Texas A&M Central Utility Plant’s Combined Heat and Power system flow
diagram displaying each major step in the system from production to generation to use.
Personnel Certifications & Licensing Certain employees at these facilities must be trained and certified in certain specialties pertaining to energy generation practices before beginning and continuing work. The following are certifications and licenses that the TCEQ (see sources 1‐5 in references cited) require for this type of facility:
Public Water System o Backflow Prevention Assembly Tester (BPAT) o Customer Service Inspector (CSI) o Groundwater Production Operator o Water Distribution Operator
Wastewater System o Wastewater Treatment Operator o Wastewater Collection Operator
Air Emissions o Visible Emissions (VE) Evaluator Certification
Processes with potential for pollution
A facility that produces electricity, such as this one, will have dozens of processes for
pollution. I have listed the following that I observed during our visit.
Thermal (heat) pollution via steam generation and release is a minor concern, though it
can cause problems for organisms and environments in the immediate area of the facility as
steam that is being released to the atmosphere can warm the ambient air temperature and
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affect the surrounding environments. In this case, this does not serve as much of a problem
since most of the surrounding environments are buildings and a car garage.
Water contamination in water used to cool equipment and systems within the facility is a very serious issue as this is a very water–intensive process and the water that is used is sent to the campus wastewater municipal plant that will treat it under certain conditions and release it back to White’s Creek that feeds into the Brazos River basin. Water at this facility has the potential to be contaminated in various ways, including being introduced to greases, oils and gases used within the facility, or with other chemicals that are added to help control a certain process. Figure 3 shows a few images of various water pipes utilized throughout the facility near equipment processing other dangerous and toxic chemicals and products.
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Figure 3 – Various types of water supply to differing equipment within the facility and their proximity to other lines carrying toxic products.
Volatile organic compounds (VOC) emissions to the atmosphere via equipment and
stacks are an environmental as well as safety and health precaution. Equipment that carries product that volatilizes with oxygen, especially gases, are prone to emit fugitive vapors to the atmosphere and surrounding environment. (EPA LDAR Guide pg. 3) Stacks are also known sources of fugitive emissions, and that is why this facility monitors their stacks carefully with CEMS, RATA and SRC units (refer to Pollution Control and Waste Minimization section).
Carbon monoxide (CO) is a by‐product from catalytic oxidation, and nitrous oxides (NOx) pollution results from selective catalytic reduction (SCR) in the boilers. Figure 4 shows the doors to the catalysts on the boiler that are used as buffers to remove NOx and SOx before reaching the monitoring units in the stack that releases to the atmosphere.
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Figure 4‐ Doors that allow access to the catalysts that remove harmful pollutants including NOx
and Sox before reaching the stack which is open to the atmosphere.
Chemicals used at the facility
• Liquid Ammonia (see figure 5)
• Chlorine
• Zinc formerly used for treating boilers
• Polymers
• Amines for pH control
• Yellow metals to protect coating on tubes
• Dechlorinate
Figure 5‐ Container of liquid ammonia waiting to be used; contained in secondary containment
to prevent leakage if a hole or spill occurs.
Pollution Control and waste minimization (air, toxics, water, waste, etc.)
CEMS units (figure 6) are used on the boilers to measure, analyze and monitor
pollutants created by the equipment and make sure that the catalysts and other buffers (figure
7) in place are working properly and don’t need to be replaced. The CEMS unit is calibrated
using tanks filled with the gases (figure 8) that it is programmed to detect. These gases are
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introduced to the sensors in the unit at lower levels to ensure that the unit is still detecting
even trace amounts of the elements and particulates that it monitors for. Figure 9 illustrates a
generic diagram of a typical CEMS unit setup (provided by Petersen in his introduction
presentation) to help us understand what processes are actually going on within a CEMS
monitoring system. Figure 10 shows details of the stack that the CEMS unit is hooked up to for
visual reference.
Figure 6‐ The left is the picture of the insides of the CEMS unit on a boiler at the Central Utility
Plant. On the right is another generic example of a CEMS unit provided by Daryl Petersen in his
introductory presentation.
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Figure 7‐ The exterior doors on the boiler where the catalysts that serve as buffers and filters
for the particulates produced by this piece of equipment. The bottom image is of a generic SCR
filter provided to us by Dr. Wilkinson for reference.
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Figure 8‐ Gas tanks used to calibrate the CEMS unit on the boiler pictured above.
Figure 9‐ A diagram depicting the typical setup for a CEMS system to monitor particulates and
emissions on a stack. The CEMS systems uses probes to monitor the opacity of the smoke being
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released to the atmosphere to ensure that it is not releasing high levels of toxins, particulates
and pollutants into the atmosphere above.
Figure 10‐ On the left is a picture of the entire stack from which we observed and took photos
of the CEMS and catalyst equipment from. The photo on the right is an access point on the side
of the stack labeling it as an exhaust stack.
All CEMS units are tested using the RATA audit, or Relative Accuracy Test Audit.
Boiler 12 (B12) also uses low NOx burners and a Flue Gas Return System (FGR) to
minimize air emissions (figure 11). A properly combusting boiler will produce almost
untraceable amounts of pollutants to the atmosphere, which is important to ensure that the
equipment is working optimally, as well as keeping levels of pollutants and particulates being
released to the atmosphere at a minimum. The CEMS unit only measures the smoke that is
being released; it cannot stop or control what is being realized, which is why optimal
combustion is important.
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Figure 11‐ This diagram, supplied by Petersen’s introductory presentation, explains the process
of combustion happening inside of the boiler.
The Gas Turbine Generator 1 (GTG1) and Heat Recovery Steam Generator (HRSG) units
(pictured in figures 12 and 13) allow for the facility to collect exhaust gas and utilize what would
otherwise be waste to generate more electricity. This equipment allows the facility to be at
least 50% more efficient than most typical fossil‐fuel supplied power plants. (Riley 2013)
Figure 12‐ The Gas Turbine Generator 1 (GTG1) produces energy from collected “waste,” or
exhaust gas.
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Figure 13‐ The Heat Recovery Steam Generator (HRSG) unit collects waste gas and uses it to
create steam to power a steam turbine or chillers that produce electricity, heat, steam and/or
cooling for the campus.
State and federal regulations associated with the site
This utility plant is regulated by the TCEQ and EPA. The following state and federal
regulations are associated with the monitoring and permitting of the processes at this facility:
Water o Public Water Supply (PWS) 0210017
Wastewater o Riverside Campus WWTP – WQ0010968002 o Main Campus WWTP – WQ0010968003 o Central Utility Plant Industrial Discharge – WQ0004002000
Air o Title V – Federal Operating Permit O – 01624
Annual report of compliance Visual emissions observations on Stationary Vents Emission inventory questionnaire (EIQ) Opacity monitoring audit on Boiler 12
o Boiler 12 – Permit #44762 Continuous Emissions Monitoring (CEMS) Compressed Gas Audit (CGA) Deviation Report
o GTG1/HRSG – Permit #91611 Continuous Emissions Monitoring (CEMS)
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Compressed Gas Audit (CGA) Deviation Report Relative Accuracy Test Audit (RATA) 16,000 hr./3 year emission compliance testing
Permit Limitations Temperature pH Chlorine Residual Oil & Grease Zinc Total Suspended Solids (TSS) Total Dissolved Solids (TDS)
Report monitoring and scheduling (refer to Source 6 in References cited) AIR
o Annual reporting of compliance for Title V Permit No. O‐01624 Submitted to TCEQ Region 9 office by May 31st each year for reporting
period of May 1st to April 30th of previous year. o Bi‐annual reporting of Boiler 12 (Permit No. 44762) non‐compliance issues
Submitted to TCEQ Region 9 office by November 23rd each year for period April 24th to October 23rd and by May 23th each year for period October 24th to April 23rd
o Bi‐annual reporting of GTG1/Boiler1 (Permit No. 91611) non‐compliance issues Submitted to TCEQ Region 9 office by August 17th each year for period
January 19th to July 18th and February 17th each year for period July 19th to January18th
o Boiler 12 or GTG1/Boiler 1 CEMS units offline due to equipment unavailability Report sent by email to TCEQ Region 9 office by end of next business day.
o Compressed Gas Audit (CGA) for Boiler 12 or GTG1/Boiler 1 CEMS units Audits completed each quarter by third party vendor on behalf of TAMU.
o Relative Accuracy Test Audit (RATA) for GTG1/Boiler 1 CEMS unit Audit completed once a year by third party vendor on behalf of TAMU.
o Opacity monitor certification for Boiler 12 CEMS Annual certification completed by third party vendor on behalf of TAMU. 16,000 hour/3 year emission compliance testing of GTG1 Testing by third party vendor. Managed and reported by UES
environmental staff. o Annual Emission Inventory for TCEQ Account No. BM0032V
Submitted electronically via TCEQ reporting program STEERS by March 31st
o Quarterly Visible Emissions Observations on Stationary Vents under Title V Permit O‐01624
Observations conducted and recorded by UES environmental staff during the first week of each new quarter.
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INDUSTRIAL WASTEWATER o Monthly Discharge Monitoring Report (DMR) for Permit No. 4002
Filed electronically to TCEQ NetDMR program by 20th of following month
References Cited
Riley, Jim. "Submission for the 3rd International District Energy Climate Award." (2013): n. pag.
District Energy Global Climate Award. TEXAS A&M UNIVERSITY Utilities & Energy Services.
Web. 23 Nov. 2014. <http://www.districtenergy.org/assets/pdfs/2013‐Global‐Climate‐
Awards‐NYC/Presentations‐etc‐for‐posting/USACHPTexasSummary.pdf>.
Us Epa, Oar, Climate Protection Partnerships Division. "Combined Heat and Power: Frequently
Asked Questions." (n.d.): n. pag. Combined Heat & Power. US Environmental Protection
Agency. Web. 23 Nov. 2014. <http://www.epa.gov/chp/documents/faq.pdf>.
"Sources, Causes and Control of Equipment Leaks." Leak Detection and Repair: A Best Practices
Guide. Washington, D.C.: U.S. Environmental Protection Agency, Office of Enforcement
and Compliance Assurance, n.d. 3‐7. Web. 23 Nov. 2017.
<http://www.epa.gov/compliance/resources/publications/assistance/ldarguide.pdf>.
Source 1‐ "Backflow Prevention Assembly Tester (BPAT)." Backflow Prevention Assembly Tester
(BPAT). Texas Commission on Environmental Quality, n.d. Web. 23 Nov. 2014.
<http://www.tceq.state.tx.us/licensing/licenses/bpatlic>.
Source 2‐ "Customer Service Inspector (CSI)." Customer Service Inspector (CSI). Texas
Commission on Environmental Quality, n.d. Web. 23 Nov. 2014.
<http://www.tceq.state.tx.us/licensing/licenses/csilic>.
Source 3‐ "Water Operators." Water Operators. Texas Commission on Environmental Quality,
n.d. Web. 23 Nov. 2014. <http://www.tceq.state.tx.us/licensing/licenses/waterlic>.
Source 4‐ "Wastewater Operators." Wastewater Operators. Texas Commission on
Environmental Quality, n.d. Web. 23 Nov. 2014.
<http://www.tceq.state.tx.us/licensing/licenses/wwlic>.
Source 5‐ "Smoke School: Visible Emissions Evaluators." Smoke School: Visible Emissions
Evaluators. Texas Commission on Environmental Quality, n.d. Web. 23 Nov. 2014.
<http://www.tceq.state.tx.us/licensing/licenses/smokelic>.
Source 6‐ Petersen, Daryl. Environmental Compliance Reporting‐ Central Utility Plant. College
Station, Texas: TAMU Utilities and Energy Services, 13 Nov. 2014. Word Document.
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Petersen, Daryl. Utility & Energy Services UES Utility Plant Overview for BESC 411. College
Station, Texas: TAMU Utilities and Energy Services, 13 Nov. 2014. Powerpoint
Presentation.