Current through Reg. 50, No. 13; March 28, 2025
Gas or liquid fuel-fired stationary internal combustion
reciprocating engines or gas turbines that operate in compliance with the
following conditions of this section are permitted by rule.
(1) The facility shall be registered by
submitting the commission's Form PI-7, Table 29 for each proposed reciprocating
engine, and Table 31 for each proposed gas turbine to the commission's Office
of Permitting, Remediation, and Registration in Austin within ten days after
construction begins. Engines and turbines rated less than 240 horsepower (hp)
need not be registered, but must meet paragraphs (5) and (6) of this section,
relating to fuel and protection of air quality. Engine hp rating shall be based
on the engine manufacturer's maximum continuous load rating at the lesser of
the engine or driven equipment's maximum published continuous speed. A
rich-burn engine is a gas-fired spark-ignited engine that is operated with an
exhaust oxygen content less than 4.0% by volume. A lean-burn engine is a
gas-fired spark-ignited engine that is operated with an exhaust oxygen content
of 4.0% by volume, or greater.
(2)
For any engine rated 500 hp or greater, subparagraphs (A) - (C) of this
paragraph shall apply.
(A) The emissions of
nitrogen oxides (NO x) shall not exceed the following
limits:
(i) 2.0 grams per horsepower-hour
(g/hp-hr) under all operating conditions for any gas-fired rich-burn
engine;
(ii) 2.0 g/hp-hr at
manufacturer's rated full load and speed, and other operating conditions,
except 5.0 g/hp-hr under reduced speed, 80-100% of full torque conditions, for
any spark-ignited, gas-fired lean-burn engine, or any compression-ignited dual
fuel-fired engine manufactured new after June 18, 1992;
(iii) 5.0 g/hp-hr under all operating
conditions for any spark-ignited, gas-fired, lean-burn two-cycle or four-cycle
engine or any compression-ignited dual fuel-fired engine rated 825 hp or
greater and manufactured after September 23, 1982, but prior to June 18,
1992;
(iv) 5.0 g/hp-hr at
manufacturer's rated full load and speed and other operating conditions, except
8.0 g/hp-hr under reduced speed, 80-100% of full torque conditions for any
spark-ignited, gas-fired, lean-burn four-cycle engine, or any
compression-ignited dual fuel-fired engine that:
(I) was manufactured prior to June 18, 1992,
and is rated less than 825 hp; or
(II) was manufactured prior to September 23,
1982;
(v) 8.0 g/hp-hr
under all operating conditions for any spark-ignited, gas-fired, two-cycle
lean-burn engine that:
(I) was manufactured
prior to June 18, 1992, and is rated less than 825 hp; or
(II) was manufactured prior to September 23,
1982;
(vi) 11.0 g/hp-hr
for any compression-ignited liquid-fired engine.
(B) For such engines which are spark-ignited
gas-fired or compression-ignited dual fuel-fired, the engine shall be equipped
as necessary with an automatic air-fuel ratio (AFR) controller which maintains
AFR in the range required to meet the emission limits of subparagraph (A) of
this paragraph. An AFR controller shall be deemed necessary for any engine
controlled with a non-selective catalytic reduction (NSCR) converter and for
applications where the fuel heating value varies more than ± 50 British
thermal unit/standard cubic feet from the design lower heating value of the
fuel. If an NSCR converter is used to reduce NOx, the
automatic controller shall operate on exhaust oxygen control.
(C) Records shall be created and maintained
by the owner or operator for a period of at least two years, made available,
upon request, to the commission and any local air pollution control agency
having jurisdiction, and shall include the following:
(i) documentation for each AFR controller,
manufacturer's, or supplier's recommended maintenance that has been performed,
including replacement of the oxygen sensor as necessary for oxygen sensor-based
controllers. The oxygen sensor shall be replaced at least quarterly in the
absence of a specific written recommendation;
(ii) documentation on proper operation of the
engine by recorded measurements of NOx and carbon
monoxide (CO) emissions as soon as practicable, but no later than seven days
following each occurrence of engine maintenance which may reasonably be
expected to increase emissions, changes of fuel quality in engines without
oxygen sensor-based AFR controllers which may reasonably be expected to
increase emissions, oxygen sensor replacement, or catalyst cleaning or catalyst
replacement. Stain tube indicators specifically designed to measure
NOx and CO concentrations shall be acceptable for this
documentation, provided a hot air probe or equivalent device is used to prevent
error due to high stack temperature, and three sets of concentration
measurements are made and averaged. Portable NOx and CO
analyzers shall also be acceptable for this documentation;
(iii) documentation within 60 days following
initial engine start-up and biennially thereafter, for emissions of NO
x and CO, measured in accordance with United States
Environmental Protection Agency (EPA) Reference Method 7E or 20 for NO
x and Method 10 for CO. Exhaust flow rate may be
determined from measured fuel flow rate and EPA Method 19. California Air
Resources Board Method A-100 (adopted June 29, 1983) is an acceptable alternate
to EPA test methods. Modifications to these methods will be subject to the
prior approval of the Source and Mobile Monitoring Division of the commission.
Emissions shall be measured and recorded in the as-found operating condition;
however, compliance determinations shall not be established during start-up,
shutdown, or under breakdown conditions. An owner or operator may submit to the
appropriate regional office a report of a valid emissions test performed in
Texas, on the same engine, conducted no more than 12 months prior to the most
recent start of construction date, in lieu of performing an emissions test
within 60 days following engine start-up at the new site. Any such engine shall
be sampled no less frequently than biennially (or every 15,000 hours of elapsed
run time, as recorded by an elapsed run time meter) and upon request of the
executive director. Following the initial compliance test, in lieu of
performing stack sampling on a biennial calendar basis, an owner or operator
may elect to install and operate an elapsed operating time meter and shall test
the engine within 15,000 hours of engine operation after the previous emission
test. The owner or operator who elects to test on an operating hour schedule
shall submit in writing, to the appropriate regional office, biennially after
initial sampling, documentation of the actual recorded hours of engine
operation since the previous emission test, and an estimate of the date of the
next required sampling.
(3) For any gas turbine rated 500 hp or more,
subparagraphs (A) and (B) of this paragraph shall apply.
(A) The emissions of
NOx shall not exceed 3.0 g/hp-hr for
gas-firing.
(B) The turbine shall
meet all applicable NO x and sulfur dioxide
(SO2) (or fuel sulfur) emissions limitations, monitoring
requirements, and reporting requirements of EPA New Source Performance
Standards Subpart GG--Standards of Performance for Stationary Gas Turbines.
Turbine hp rating shall be based on turbine base load, fuel lower heating
value, and International Standards Organization Standard Day Conditions of 59
degrees Fahrenheit, 1.0 atmosphere and 60% relative humidity.
(4) Any engine or turbine rated
less than 500 hp or used for temporary replacement purposes shall be exempt
from the emission limitations of paragraphs (2) and (3) of this section.
Temporary replacement engines or turbines shall be limited to a maximum of 90
days of operation after which they shall be removed or rendered physically
inoperable.
(5) Gas fuel shall be
limited to: sweet natural gas or liquid petroleum gas, fuel gas containing no
more than ten grains total sulfur per 100 dry standard cubic feet, or field
gas. If field gas contains more than 1.5 grains hydrogen sulfide or 30 grains
total sulfur compounds per 100 standard cubic feet (sour gas), the engine owner
or operator shall maintain records, including at least quarterly measurements
of fuel hydrogen sulfide and total sulfur content, which demonstrate that the
annual SO 2 emissions from the facility do not exceed 25
tons per year (tpy). Liquid fuel shall be petroleum distillate oil that is not
a blend containing waste oils or solvents and contains less than 0.3% by weight
sulfur.
(6) There will be no
violations of any National Ambient Air Quality Standard (NAAQS) in the area of
the proposed facility. Compliance with this condition shall be demonstrated by
one of the following three methods:
(A)
ambient sampling or dispersion modeling accomplished pursuant to guidance
obtained from the executive director. Unless otherwise documented by actual
test data, the following nitrogen dioxide (NO
2)/NOx ratios shall be used for
modeling NO2 NAAQS;
Attached
Graphic
(B) all
existing and proposed engine and turbine exhausts are released to the
atmosphere at a height at least twice the height of any surrounding
obstructions to wind flow. Buildings, open-sided roofs, tanks, separators,
heaters, covers, and any other type of structure are considered as obstructions
to wind flow if the distance from the nearest point on the obstruction to the
nearest exhaust stack is less than five times the lesser of the height, Hb, and
the width, Wb, where:
Attached
Graphic
(C) the
total emissions of NOx (nitrogen oxide plus
NO2) from all existing and proposed facilities on the
property do not exceed the most restrictive of the following:
(ii) the value (0.3125 D) tpy, where D equals
the shortest distance in feet from any existing or proposed stack to the
nearest property line.
(7) Upon issuance of a standard permit for
electric generating units, registrations under this section for engines or
turbines used to generate electricity will no longer be accepted, except for:
(A) engines or turbines used to provide power
for the operation of facilities registered under the Air Quality Standard
Permit for Concrete Batch Plants;
(B) engines or turbines satisfying the
conditions for facilities permitted by rule under Subchapter E of this title
(relating to Aggregate and Pavement); or
(C) engines or turbines used exclusively to
provide power to electric pumps used for irrigating crops.
