Wisconsin Administrative Code, Subchapter II, Section NR 440.45 - Kraft pulp mills | Wisconsin Administrative Code

(1) APPLICABILITY AND DESIGNATION OF AFFECTED FACILITY.

(a) The provisions of this section are applicable to the following affected facilities in kraft pulp mills: digester system, brown stock washer system, multiple-effect evaporator system, recovery furnace, smelt dissolving tank, lime kiln and condensate stripper system. In pulp mills where kraft pulping is combined with neutral sulfite semichemical pulping, the provisions of this section are applicable when any portion of the material charged to an affected facility is produced by the kraft pulping operation.

(b) Except as noted in sub. (4) (a) 1. d., any facility under par. (a) that commences construction or modification after September 24, 1976, is subject to the requirements of this section.

(2) DEFINITIONS. As used in this section, terms not defined in this subsection have the meanings given in s. NR 440.02.

(a) "Black liquor oxidation system" means the vessels used to oxidize, with air or oxygen, the black liquor, and associated storage tanks.

(b) "Black liquor solids" means the dry weight of the solids which enter the recovery furnace in the black liquor.

(c) "Brown stock washer system" means brown stock washers and associated knotters, vacuum pumps and filtrate tanks used to wash the pulp following the digester system. Diffusion washers are excluded from this definition.

(d) "Condensate stripper system" means a column and associated condensers used to strip, with air or steam, TRS compounds from condensate streams from various processes within a kraft pulp mill.

(e) "Cross recovery furnace" means a furnace used to recover chemicals consisting primarily of sodium and sulfur compounds by burning black liquor which on a quarterly basis contains more than 7 weight percent of the total pulp solids from the neutral sulfite semichemical process and has a green liquor sulfidity of more than 28%.

(f) "Digester system" means each continuous digester or each batch digester used for the cooking of wood in white liquor, and associated flash tanks, blow tanks, chip steamers and condensers.

(g) "Green liquor sulfidity" means the sulfidity of the liquor which leaves the smelt dissolving tank.

(h) "Kraft pulp mill" means any stationary source which produces pulp from wood by cooking or digesting wood chips in a water solution of sodium hydroxide and sodium sulfide (white liquor) at high temperature and pressure. Regeneration of the cooking chemicals through a recovery process is also considered part of the kraft pulp mill.

(i) "Lime kiln" means a unit used to calcine lime mud, which consists primarily of calcium carbonate, into quicklime, which is calcium oxide.

(j) "Multiple-effect evaporator system" means the multiple-effect evaporators and associated condensers and hotwells used to concentrate the spent cooking liquid that is separated from the pulp (black liquor).

(k) "Neutral sulfite semichemical pulping operation" means any operation in which pulp is produced from wood by cooking or digesting wood chips in a solution of sodium sulfite and sodium bicarbonate, followed by mechanical defibrating (grinding).

(L) "Recovery furnace" means either a straight kraft recovery furnace or a cross recovery furnace, and includes the direct-contact evaporator for a direct-contact furnace.

(m) "Smelt dissolving tank" means a vessel used for dissolving the smelt collected from the recovery furnace.

(n) "Straight kraft recovery furnace" means a furnace used to recover chemicals consisting primarily of sodium and sulfur compounds by burning black liquor which on a quarterly basis contains 7 weight percent or less of the total pulp solids from the neutral sulfite semichemical process or has green liquor sulfidity of 28% or less.

(o) "Total reduced sulfur" or "TRS" means the sum of the sulfur compounds hydrogen sulfide, methyl mercaptan, dimethyl sulfide, and dimethyl disulfide that are released during the kraft pulping operation and measured by Method 16 of 40 CFR part 60, Appendix A, incorporated by reference in s. NR 440.17(1).

(3) STANDARD FOR PARTICULATE MATTER.

(a) On and after the date on which the performance test required to be conducted by s. NR 440.08 is completed, no owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere:

1. From any recovery furnace any gases which:

a. Contain particulate matter in excess of 0.10 g/dscm (0.044 gr/dscf) corrected to 8% oxygen.

b. Exhibit 35% opacity or greater.

2. From any smelt dissolving tank any gases which contain particulate matter in excess of 0.10 g/kg black liquor solids, dry weight (0.20 lb/ton black liquor solids, dry weight).

3. From any lime kiln any gases which contain particulate matter in excess of:

a. 0.15 g/dscm (0.066 gr/dscf) corrected to 10% oxygen, when gaseous fossil fuel is burned.

b. 0.30 g/dscm (0.13 gr/dscf) corrected to 10% oxygen, when liquid fossil fuel is burned.

(4) STANDARD FOR TOTAL REDUCED SULFUR (TRS).

(a) On and after the date on which the performance test required to be conducted by s. NR 440.08 is completed, no owner or operator subject to the provisions of this section may cause to be discharged into the atmosphere:

1. From any digester system, brown stock washer system, multiple-effect evaporator system or condensate stripper system, any gases which contain TRS in excess of 5.0 ppm by volume on a dry basis, corrected to 10% oxygen, unless one of the following conditions is met:

a. The gases are combusted in a lime kiln subject to the provisions of subd. 5.

b. The gases are combusted in a recovery furnace subject to the provisions of subd. 2. or 3.

c. The gases are combusted with other waste gases in an incinerator or other device, or combusted in a lime kiln or recovery furnace not subject to the provisions of this section, and are subjected to a minimum temperature of 650°C (1200° F) for at least 0.5 second.

d. It has been demonstrated to the department's satisfaction by the owner or operator that incinerating the exhaust gases from a new, modified or reconstructed brown stock washer system in an existing facility is technologically or economically not feasible. Any exempt system shall become subject to the provisions of this section if the facility is changed so that the gases can be incinerated.

e. The gases from the digester system, brown stock washer system or condensate stripper system are controlled by a means other than combustion. In this case, these systems may not discharge any gases to the atmosphere which contain TRS in excess of 5.0 ppm by volume on a dry basis, uncorrected for oxygen content.

f. The uncontrolled exhaust gases from a new, modified, or reconstructed digester system contain TRS less than 0.0050 g/kg air dried pulp (0.010 lb/ton air dried pulp).

2. From any straight kraft recovery furnace any gases which contain TRS in excess of 5.0 ppm by volume on a dry basis, corrected to 8% oxygen.

3. From any cross recovery furnace any gases which contain TRS in excess of 25 ppm by volume on a dry basis, corrected to 8% oxygen.

4. From any smelt dissolving tank any gases which contain TRS in excess of 0.016 g/kg black liquor solids, as H2S (0.033 lb/ton black liquor solids, as H2S).

5. From any lime kiln any gases which contain TRS in excess of 8.0 ppm by volume on a dry basis, corrected to 10% oxygen.

(5) MONITORING OF EMISSIONS AND OPERATIONS.

(a) Any owner or operator subject to the provisions of this section shall install, calibrate, maintain and operate the following continuous monitoring systems:

1. A continuous monitoring system to monitor and record the opacity of the gases discharged into the atmosphere from any recovery furnace. The span of this system shall be set at 70% opacity.

2. Continuous monitoring systems to monitor and record the concentration of TRS emissions on a dry basis and the percent of oxygen by volume on a dry basis in the gases discharged into the atmosphere from any lime kiln, recovery furnace, digester system, brown stock washer system, multiple-effect evaporator system, or condensate stripper system, except where the provisions of sub. (4) (a) 1. c. or d. apply. These systems shall be located downstream of the control devices and the spans of these continuous monitoring systems shall be set:

a. At a TRS concentration of 30 ppm for the TRS continuous monitoring system, except that for any cross recovery furnace the span shall be set at 50 ppm.

b. At 25% oxygen for the continuous oxygen monitoring system.

(b) Any owner or operator subject to the provisions of this section shall install, calibrate, maintain and operate the following continuous monitoring devices:

1. For any incinerator, a monitoring device which measures the combustion temperature at the point of incineration of effluent gases which are emitted from any digester system, brown stock washer system, multiple-effect evaporator system, black liquor oxidation system or condensate stripper system where the provisions of sub. (4) (a) 1. c. apply. The monitoring device shall be certified by the manufacturer to be accurate within " one percent of the temperature being measured.

2. For any lime kiln or smelt dissolving tank using a scrubber emission control device:

a. A monitoring device for the continuous measurement of the pressure loss of the gas stream through the control equipment. The monitoring device shall be certified by the manufacturer to be accurate to within a gauge pressure of " 500 pascals (ca. 2 inches water gauge pressure).

b. A monitoring device for the continuous measurement of the scrubbing liquid supply pressure to the control equipment. The monitoring device shall be certified by the manufacturer to be accurate within " 15% of design scrubbing liquid supply pressure. The pressure sensor or tap shall be located close to the scrubber liquid discharge point. The department may approve alternative locations.

(c) Any owner or operator subject to the provisions of this section shall, except where the provisions of sub. (4) (a) 1. d. or 4. apply, perform the following:

1. Calculate and record on a daily basis 12-hour average TRS concentrations for the 2 consecutive periods of each operating day. Each 12-hour average shall be determined as the arithmetic mean of the appropriate 12 contiguous one-hour average total reduced sulfur concentrations provided by each continuous monitoring system installed under par. (a) 2.

2. Calculate and record on a daily basis 12-hour average oxygen concentrations for the 2 consecutive periods of each operating day for the recovery furnace and lime kiln. These 12-hour averages shall correspond to the 12-hour average TRS concentrations under subd. 1. and shall be determined as an arithmetic mean of the appropriate 12 contiguous one-hour average oxygen concentrations provided by each continuous monitoring system installed under par. (a) 2.

3. Using the following equation, correct all 12-hour average TRS concentrations to 10 volume percent oxygen, except that all 12-hour average TRS concentrations from a recovery furnace shall be corrected to 8 volume percent oxygen instead of 10%, and all 12-hour average TRS concentrations from a facility to which the provisions of sub. (4) (a) 1. e. apply may not be corrected for oxygen content:

Ccorr = Cmeas (21 - X)/(21 - Y)

where:

Ccorr is the concentration corrected for oxygen

Cmeas is the concentration uncorrected for oxygen

X is the volumetric oxygen concentration in percentage to be corrected to (8% for recovery furnaces and 10% for lime kilns, incinerators, or other devices)

Y is the measured 12-hour average volumetric oxygen concentration

4. Record once per shift measurements obtained from the continuous monitoring devices installed under par. (b) 2.

(d) For the purpose of reports required under s. NR 440.07(3), any owner or operator subject to the provisions of this section shall report semiannually periods of excess emissions as follows:

1. For emission from any recovery furnace, periods of excess emissions are:

a. All 12-hour average TRS concentrations above 5 ppm by volume for straight kraft recovery furnaces and above 25 ppm by volume for cross recovery furnaces.

b. All 6-minute average opacities that exceed 35%.

2. For emissions from any lime kiln, periods of excess emissions are all 12-hour average TRS concentration above 8 ppm by volume.

3. For emissions from any digester system, brown stock washer system, multiple-effect evaporator system or condensate stripper system, period of excess emissions are:

a. All 12-hour average TRS concentrations above 5 ppm by volume unless the provisions of sub. (4) (a) 1. a., b. or d. apply; or

b. All periods in excess of 5 minutes and their duration during which the combustion temperature at the point of incineration is less than 650° C (1200° F) where the provisions of sub. (4) (a) 1. c. apply.

(e) The department may not consider periods of excess emissions reported under par. (d) to be indicative of a violation of s. NR 440.11(4), provided that:

1. The percent of the total number of possible contiguous periods of excess emissions in a quarter (excluding periods of startup, shutdown, or malfunction and periods when the facility is not operating) during which excess emissions occur does not exceed:

a. One percent for TRS emissions from recovery furnaces.

b. Six percent for average opacities from recovery furnaces.

2. The department determines that the affected facility, including air pollution control equipment, is maintained and operated in a manner which is consistent with good air pollution control practice for minimizing emissions during periods of excess emissions.

(f) The procedures under s. NR 440.13 shall be followed for installation, evaluation and operation of the continuous monitoring systems required under this subsection.

1. All continuous monitoring systems shall be operated in accordance with the applicable procedures under Performance Specifications 1, 3 and 5 of 40 CFR part 60, Appendix B, incorporated by reference in s. NR 440.17(1).

2. Quarterly accuracy determinations and daily calibration drift tests shall be performed in accordance with Procedure 1 of 40 CFR part 60, Appendix F, incorporated by reference in s. NR 440.17(1).

(6) TEST METHODS AND PROCEDURES.

(a) In conducting the performance tests required in s. NR 440.08, the owner or operator shall use as reference methods and procedures the test methods in Appendix A of 40 CFR part 60, incorporated by reference in s. NR 440.17, or other methods and procedures in this subsection, except as provided in s. NR 440.08(2). Acceptable alternative methods and procedures are given in par. (f).

(b) The owner or operator shall determine compliance with the particulate matter standards in sub. (3) (a) 1. and 3. as follows:

1. Method 5 shall be used to determine the particulate matter concentration. The sampling time and sample volume for each run shall be at least 60 minutes and 0.90 dscm (31.8 dscf). Water shall be used as the cleanup solvent instead of acetone in the sample recovery procedure. The particulate concentration shall be corrected to the appropriate oxygen concentration according to sub. (5) (c) 3.

2. The emission rate correction factor, integrated sampling and analysis procedure of Method 3B shall be used to determine the oxygen concentration. The gas sample shall be taken at the same time and at the same traverse points as the particulate sample.

3. Method 9 and the procedures in s. NR 440.11 shall be used to determine opacity.

(c) The owner or operator shall determine compliance with the particulate matter standard in sub. (3) (a) 2. as follows:

1. The emission rate (E) of particulate matter shall be computed for each run using the following equation:

E = cs Qsd/BLS

where:

E is the emission rate of particulate matter, g/kg (lb/ton) of BLS

cs is the concentration of particulate matter, g/dscm (lb/dscf)

Qsd is the volumetric flow rate of effluent gas, dscm/hr (dscf/hr)

BLS is the black liquor solids (dry weight) feed rate, kg/hr (ton/hr)

2. Method 5 shall be used to determine the particulate matter concentration (cs) and the volumetric flow rate (Q sd) of the effluent gas. The sampling time and sample volume shall be at least 60 minutes and 0.90 dscm (31.8 dscf). Water shall be used instead of acetone in the sample recovery.

3. Process data shall be used to determine the black liquor solids (BLS) feed rate on a dry weight basis.

(d) The owner or operator shall determine compliance with the TRS standards in sub. (4), except sub. (4) (a) 1. f. and 4., as follows:

1. Method 16 shall be used to determine the TRS concentration. The TRS concentration shall be corrected to the appropriate oxygen concentration using the procedure in sub. (5) (c) 3. The sampling time shall be at least 3 hours, but no longer than 6 hours.

2. The emission rate correction factor, integrated sampling and analysis procedure of Method 3B shall be used to determine the oxygen concentration. The sample shall be taken over the same time period as the TRS samples.

3. When determining whether a furnace is a straight kraft recovery furnace or a cross recovery furnace, TAPPI Method T624, incorporated by reference in s. NR 440.17, shall be used to determine sodium sulfide, sodium hydroxide, and sodium carbonate. These determinations shall be made 3 times daily from the green liquor, and the daily average values shall be converted to sodium oxide (Na2O) and substituted into the following equation to determine the green liquor sulfidity:

See PDF for diagram

3. Method 2 shall be used to determine the volumetric flow rate (Qsd) of the effluent gas.

4. Process data shall be used to determine the black liquor feed rate or the pulp production rate (P).

(f) The owner or operator may use the following as alternatives to the reference methods and procedures specified in this subsection:

1. For Method 5, Method 17 may be used if a constant value of 0.009 g/dscm (0.004 gr/dscf) is added to the results of Method 17 and the stack temperature is no greater than 204°C (400°F).

2. In place of Method 16, Method 16A or 16B may be used.

Wisconsin Administrative CodeDepartment of Natural ResourcesNR 400-499 - Environmental Protection - Air Pollution ControlChapter NR 440 - Standards of performance for new stationary sourcesSubchapter II - Standards of PerformanceSection NR 440.45 - Kraft pulp mills

Wisconsin Administrative Code
Department of Natural Resources
NR 400-499 - Environmental Protection - Air Pollution Control
Chapter NR 440 - Standards of performance for new stationary sources
Subchapter II - Standards of Performance
Section NR 440.45 - Kraft pulp mills