Regulatory Text: 
Texas TNRCC Chapter 117 –  Control of Air Pollution from Nitrogen Compounds

§117.10.  Definitions.
As adopted by TNRCC April 19, 2000, effective May 11, 2000

(Approved by EPA March 16, 2001 (66 FR 15195) effective April 16, 2001)

     Unless specifically defined in the Texas Clean Air Act or Chapter 101 of this title (relating to General Air Quality Rules), the terms in this chapter shall have the meanings commonly used in the field of air pollution control.  Additionally, the following meanings apply, unless the context clearly indicates otherwise.

     (1)  Annual capacity factor - The total annual fuel consumed by a unit divided by the fuel which could be consumed by the unit if operated at its maximum rated capacity for 8,760 hours per year.

     (2)  Applicable ozone nonattainment area - The following areas, as designated pursuant to the 1990 Federal Clean Air Act Amendments.

          (A)  Beaumont/Port Arthur (BPA) ozone nonattainment area - An area consisting of Hardin, Jefferson, and Orange Counties.

          (B)  Dallas/Fort Worth (DFW) ozone nonattainment area - An area consisting of Collin, Dallas, Denton, and Tarrant Counties.

          (C)  Houston/Galveston (HGA) ozone nonattainment area - An area consisting of Brazoria, Chambers, Fort Bend, Galveston, Harris, Liberty, Montgomery, and Waller Counties.

     (3)  Auxiliary steam boiler - Any combustion equipment within an electric power generating system, as defined in this section, that is used to produce steam for purposes other than generating electricity.

     (4)  Average activity level for fuel oil firing - The product of an electric utility unit's maximum rated capacity for fuel oil firing and the average annual capacity factor for fuel oil firing for the period from January 1, 1990 to December 31, 1993.

     (5)  Block one-hour average - An hourly average of data, collected starting at the beginning of each clock hour of the day and continuing until the start of the next clock hour.

     (6)  Boiler or steam generator - Any combustion equipment fired with solid, liquid, and/or gaseous fuel used to produce steam.

     (7)  Btu - British thermal unit.

     (8)  Chemical processing gas turbine - A gas turbine that vents its exhaust gases into the operating stream of a chemical process.

     (9)  Continuous emissions monitoring system (CEMS) - The total equipment necessary for the continuous determination and recordkeeping of process gas concentrations and emission rates in units of the applicable emission limitation.

     (10)  Daily - A calendar day starting at midnight and continuing until midnight the following day.

     (11)  Electric power generating system - One electric power generating system consists of either:

          (A)  All boilers, steam generators, auxiliary steam boilers, and stationary gas turbines that generate electric energy for compensation; are owned or operated by a municipality or a Public Utility Commission of Texas regulated utility, or any of its successors; and are entirely located in one of the following ozone nonattainment areas:

               (i)  Beaumont/Port Arthur;

               (ii)  Dallas/Fort Worth;

               (iii)  Houston/Galveston; or

          (B)  All boilers, steam generators, auxiliary steam boilers, and stationary gas turbines that generate electric energy for compensation; are owned or operated by an electric cooperative, independent power producer, municipality, river authority, or public utility, or any of its successors; and are located in Atascosa, Bastrop, Bexar, Brazos, Calhoun, Cherokee, Fannin, Fayette, Freestone, Goliad, Gregg, Grimes, Harrison, Henderson, Hood, Hunt, Lamar, Limestone, Marion, McLennan, Milam, Morris, Nueces, Parker, Red River, Robertson, Rusk, Titus, Travis, Victoria, or Wharton County.

     (12)  Functionally identical replacement - A unit that performs the same function as the existing unit which it replaces, with the condition that the unit replaced must be physically removed or rendered permanently inoperable before the unit replacing it is placed into service.

     (13)  Heat input - The chemical heat released due to fuel combustion in a unit, using the higher heating value of the fuel.  This does not include the sensible heat of the incoming combustion air. In the case of carbon monoxide (CO) boilers, the heat input includes the enthalpy of all regenerator off-gases and the heat of combustion of the incoming carbon monoxide and of the auxiliary fuel.  The enthalpy change of the fluid catalytic cracking unit regenerator off-gases refers to the total heat content of the gas at the temperature it enters the CO boiler, referring to the heat content at 60 degrees Fahrenheit, as being zero.

     (14)  High heat release rate - A ratio of boiler design heat input to firebox volume (as bounded by the front firebox wall where the burner is located, the firebox side waterwall, and extending to the level just below or in front of the first row of convection pass tubes) greater than or equal to 70,000 British thermal units (Btu) per hour per cubic foot.

     (15)  Horsepower rating - The engine manufacturer's maximum continuous load rating at the lesser of the engine or driven equipment's maximum published continuous speed.

     (16)  Industrial boiler or steam generator - Any combustion equipment, not including utility or auxiliary steam boilers as defined in this section, fired with liquid, solid, or gaseous fuel, that is used to produce steam.

     (17)  International Standards Organization (ISO) conditions - ISO standard conditions of 59 degrees Fahrenheit, 1.0 atmosphere, and 60% relative humidity.

     (18)  Large DFW system - All boilers, steam generators, auxiliary steam boilers, and stationary gas turbines that are located in the Dallas/Fort Worth ozone nonattainment area, are part of one electric power generating system, and, on January 1, 2000, had a combined electric generating capacity equal to or greater than 500 megawatts.

     (19)  Lean-burn engine - A spark-ignited or compression-ignited, Otto cycle, diesel cycle, or two-stroke engine that is not capable of being operated with an exhaust stream oxygen concentration equal to or less than 0.5% by volume, as originally designed by the manufacturer.

     (20)  Low annual capacity factor boiler, process heater, or gas turbine supplemental waste heat recovery unit - A commercial, institutional, or industrial boiler; process heater; or gas turbine supplemental waste heat recovery unit with maximum rated capacity:

          (A)  greater than or equal to 40 million Btu per hour (MMBtu/hr), but less than 100 MMBtu/hr and an annual heat input less than or equal to 2.8(1011) Btu per year (Btu/yr), based on a rolling 12-month average; or

          (B)  greater than or equal to 100 MMBtu/hr and an annual heat input less than or equal to 2.2(1011) Btu/yr, based on a rolling 12-month average.

     (21)  Low annual capacity factor stationary gas turbine or stationary internal combustion engine - A stationary gas turbine or stationary internal combustion engine which is demonstrated to operate less than 850 hours per year, based on a rolling 12-month average.

     (22)  Low heat release rate - A ratio of boiler design heat input to firebox volume less than 70,000 Btu per hour per cubic foot.

     (23)  Major source - Any stationary source or group of sources located within a contiguous area and under common control that emits or has the potential to emit:

          (A)  at least 50 tons per year (tpy) of nitrogen oxides (NOx) and is located in the Beaumont/Port Arthur ozone nonattainment area;

          (B)  at least 50 tpy of NOx and is located in the Dallas/Fort Worth ozone nonattainment area;

          (C)  at least 25 tpy of NOx and is located in the Houston/Galveston ozone nonattainment area; or

          (D)  the amount specified in the major source definition contained in the Prevention of Significant Deterioration of Air Quality regulations promulgated by EPA in Title 40 Code of Federal Regulations (CFR) §52.21 as amended June 3, 1993 (effective June 3, 1994) and is located in Atascosa, Bastrop, Bexar, Brazos, Calhoun, Cherokee, Comal, Ellis, Fannin, Fayette, Freestone, Goliad, Gregg, Grimes, Harrison, Hays, Henderson, Hood, Hunt, Lamar, Limestone, Marion, McLennan, Milam, Morris, Nueces, Parker, Red River, Robertson, Rusk, Titus, Travis, Victoria, or Wharton County.

     (24)  Maximum rated capacity - The maximum design heat input, expressed in MMBtu/hr, unless:

          (A)  the unit is a boiler, utility boiler, or process heater operated above the maximum design heat input (as averaged over any one-hour period), in which case the maximum operated hourly rate shall be used as the maximum rated capacity; or

          (B)  the unit is limited by operating restriction or permit condition to a lesser heat input, in which case the limiting condition shall be used as the maximum rated capacity; or

          (C)  the unit is a stationary gas turbine, in which case the manufacturer's rated heat consumption at the International Standards Organization (ISO) conditions shall be used as the maximum rated capacity, unless limited by permit condition to a lesser heat input, in which case the limiting condition shall be used as the maximum rated capacity; or

          (D)  the unit is a stationary, internal combustion engine, in which case the manufacturer's rated heat consumption at Diesel Equipment Manufacturer's Association or ISO conditions shall be used as the maximum rated capacity, unless limited by permit condition to a lesser heat input, in which case the limiting condition shall be used as the maximum rated capacity.

     (25)  Megawatt (MW) rating - The continuous MW rating or mechanical equivalent by a gas turbine manufacturer at ISO conditions, without consideration to the increase in gas turbine shaft output and/or the decrease in gas turbine fuel consumption by the addition of energy recovered from exhaust heat.

     (26)  Nitric acid - Nitric acid which is 30% to 100% in strength.

     (27)  Nitric acid production unit - Any source producing nitric acid by either the pressure or atmospheric pressure process.

     (28)  Nitrogen oxides (NOx) - The sum of the nitric oxide and nitrogen dioxide in the flue gas or emission point, collectively expressed as nitrogen dioxide.

     (29)  Parts per million by volume (ppmv) - All ppmv emission limits specified in this chapter are referenced on a dry basis.

     (30)  Peaking gas turbine or engine - A stationary gas turbine or engine used intermittently to produce energy on a demand basis.

     (31)  Plant-wide emission limit - The ratio of the total allowable nitrogen oxides mass emissions rate dischargeable into the atmosphere from affected units at a major source when firing at their maximum rated capacity to the total maximum rated capacities for those units.

     (32)  Plant-wide emission rate - The ratio of the total actual nitrogen oxides mass emissions rate discharged into the atmosphere from affected units at a major source when firing at their maximum rated capacity to the total maximum rated capacities for those units.

     (33)  Predictive emission monitoring system (PEMS) - The total equipment necessary for the continuous determination and recordkeeping of process gas concentrations and emission rates using process or control device operating parameter measurements and a conversion equation, graph, or computer program to produce results in units of the applicable emission limitation.

     (34)  Process heater - Any combustion equipment fired with liquid and/or gaseous fuel which is used to transfer heat from combustion gases to a process fluid, superheated steam, or water for the purpose of heating the process fluid or causing a chemical reaction.  The term "process heater" does not apply to any unfired waste heat recovery heater that is used to recover sensible heat from the exhaust of any combustion equipment, or to boilers or steam generators as defined in this section.

     (35)  Rich-burn engine - A spark-ignited, Otto cycle, four-stroke, naturally aspirated or turbocharged engine that is capable of being operated with an exhaust stream oxygen concentration equal to or less than 0.5% by volume, as originally designed by the manufacturer.

     (36)  Small DFW system - All boilers, steam generators, auxiliary steam boilers, and stationary gas turbines that are located in the Dallas/Fort Worth ozone nonattainment area, are part of one electric power generating system, and, on January 1, 2000, had a combined electric generating capacity less than 500 megawatts.

     (37)  Stationary gas turbine - Any gas turbine system that is gas and/or liquid fuel fired with or without power augmentation.  This unit is either attached to a foundation at a major source or is portable equipment operated at a specific major source for more than 90 days in any 12-month period.  Two or more gas turbines powering one shaft shall be treated as one unit.
     (38)  Stationary internal combustion engine - A reciprocating engine that remains or will remain at a location (a single site at a building, structure, facility, or installation) for more than 12 consecutive months.  Included in this definition is any engine that, by itself or in or on a piece of equipment, is portable, meaning designed to be and capable of being carried or moved from one location to another.  Indicia of portability include, but are not limited to, wheels, skids, carrying handles, dolly, trailer, or platform.  Any engine (or engines) that replaces an engine at a location and that is intended to perform the same or similar function as the engine being replaced is included in calculating the consecutive residence time period.  An engine is considered stationary if it is removed from one location for a period and then returned to the same location in an attempt to circumvent the consecutive residence time requirement.

     (39)  System-wide emission limit - The ratio of the total allowable nitrogen oxides mass emissions rate dischargeable into the atmosphere from affected units in an electric power generating system or portion thereof located within a single ozone nonattainment area when firing at their maximum rated capacity to the total maximum rated capacities for those units.  For fuel oil firing, average activity levels shall be used in lieu of maximum rated capacities for the purpose of calculating the system-wide emission limit.

     (40)  System-wide emission rate - The ratio of the total actual nitrogen oxides mass emissions rate discharged into the atmosphere from affected units in an electric power generating system or portion thereof located within a single ozone nonattainment area when firing at their maximum rated capacity to the total maximum rated capacities for those units.  For fuel oil firing, average activity levels shall be used in lieu of maximum rated capacities for the purpose of calculating the system-wide emission rate.

     (41)  Thirty-day rolling average - An average, calculated for each day that fuel is combusted in a unit, of all the hourly emissions data for the preceding 30 days that fuel was combusted in the unit.

     (42)  Twenty-four hour rolling average - An average, calculated for each hour that fuel is combusted (or acid is produced, for a nitric or adipic acid production unit), of all the hourly emissions data for the preceding 24 hours that fuel was combusted in the unit. 

     (43)  Unit - Any boiler, steam generator, process heater, stationary gas turbine, or stationary internal combustion engine, as defined in this section.

     (44)  Utility boiler or steam generator - Any combustion equipment owned or operated by a municipality or Public Utility Commission of Texas regulated utility, fired with solid, liquid, and/or gaseous fuel, used to produce steam for the purpose of generating electricity.

     (45)  Wood - Wood, wood residue, bark, or any derivative fuel or residue thereof in any form, including, but not limited to, sawdust, sander dust, wood chips, scraps, slabs, millings, shavings, and processed pellets made from wood or other forest residues.

************* end tx 117.10 adopted April 19, 2000 ****************b351**