New Hampshire Department of Environmental Services
PERMIT APPLICATION REVIEW SUMMARY Facility: Location: AFS #:
Greenova, LLC Berlin 3300790123
Application #:
08-0277
Air Resources Division P.O. Box 95, 29 Hazen Drive Concord, NH 03302-0095 Phone: 603-271-1370 Fax: 603-271-7053 Engineer:
Barbara Dorfschmidt
Date:
8/21/08
Page 1 of 5
PROJECT DESCRIPTION Greenova has submitted an application for a proposed wood fuel pellet mill. The company was recently issued a Temporary Permit, FP-T-0163, for a similar operation. After this permit was issued the company decided to revise their construction plans for the new facility and build the operations in two stages. This application covers the first stage of the construction. Prior to the start of the second stage of construction, the company will need to submit an application detailing any new equipment that will be installed at that time. CHANGES FROM PREVIOUS PERMIT The originally proposed facility was designed to produce 180,000 metric tons per year of wood-pellet fuel. The permitted devices include a wood dryer heated by a wood-fired burner, hammer mills, pellet coolers, storage silos and pellet loadout and packaging operations. Emissions from the dryer/burner system were to be controlled by a WESP and RTO. The staged approach to the construction and operation of the facility will affect the list of devices and pollution control equipment listed in the permit. Specifically, the first stage would involve constructing a wood fuel pellet facility that would produce approximately half the capacity of the intended full capacity mill. This approach would involve utilizing a smaller burner/dryer and fewer pellet forming mills in the first phase. As a consequence to this first stage’s reduced production capacity, the WESP and RTO air pollution controls on the dryer stack would not be required to meet air quality standards. These controls may be added to the dryer exhaust stack during the construction of the second stage (full capacity). Note that the previously issued Temporary Permit will be cancelled after the new permit is issued. FACILITY DESCRIPTION The proposed wood-pellet manufacturing facility will be initially designed and built to produce 96,000 metric tons per year of wood-pellet fuel. The manufacturing process converts wood logs into wood pellet fuel suitable for either residential or industrial use. The manufacturing phases are wood receiving & chipping, wood chip drying, pellet forming, and packaging/shipping. Wood is received on site in log form. After the logs have been debarked (the bark will be not be used in the process) a whole-log chipper will be used to produce chips suitable for the drying process. The wood chips are conveyed into a rotary kiln dryer which reduces chip moisture content from approximately 50% to approximately 10%. Hot air for the drying process is produced in a wood-fired heat generator. Both the wood feed to the dryer and the wood used as fuel in the burner will be approximately 70% hardwood and 30% softwood. After the dryer, the wood chips are conveyed to a secondary hammer mill to be ground into the size suitable for use in the pellet process. The secondary hammer mill has an induced draft fan and baghouse. The air flow provided by the fan pulls the ground wood down through the secondary hammer mill discharge gratings, and through a duct into the pelleting building. The secondary hammer discharge baghouse drops the ground wood into a dry material storage vessel. The storage vessel feeds material down into the three pellet presses. The pellets leaving the pellet presses are hot, and must be cooled. The pellets are sent through a pellet cooler. The pellet cooler air is discharged through a separator cyclone, and the cooled pellets are conveyed to the pellet bagging line or to a bulkstorage A-frame structure. Pellets are shipped out by truck as bulk shipments or bagged shipments. The bagging system is an automatic integrated process consisting of the following stages: weighing, bagging and palletizing. Fine particles created while handling the pellets in the weighing and bagging process are captured by a vacuum and baghouse system. This material is discharged from the baghouse to be fed back into the process feedstock.
PERMIT APPLICATION REVIEW SUMMARY Facility: Location: AFS #:
Greenova, LLC Berlin 3300790123
Application #:
08-0277
Engineer:
Barbara Dorfschmidt
Date:
8/21/08
Page 2 of 5
PROCESS/DEVICE DESCRIPTION The following table summarizes the emission points for the facility: Device Chip storage pneumatic convey system with baghouse Wood-fired burner
Rotary Dryer with multiclone Pellet Mill pneumatic convey system and Secondary Hammer Mill with baghouse Dryer fuel pneumatic convey system with baghouse Pellet Cooler and 3 Pellet Mills with multiclone Pellet Packaging with baghouse Pellet Mill Storage Silo with baghouse 2 Pellet Loadout Silos with baghouse 6 Pellet Storage Silos (only one pellet storage silo will be in use at any one time) with baghouse
Maximum Capacity 70,548 lb/hr wood chips 50 MMBtu/hr wood bark; moisture = 42% equivalent to 5.71 ton/hr using a heating value of wet wood (50% moisture) of 4,375 Btu/lb 14.43 oven dried tons, ODT wood chips 31,800 lb/hr dry wood chips 5,346 lb/hr wood chips 28,660 lb/hr wood pellet (9,553 lb/hr for each pellet mill) 26,400 lb/hr wood pellets 26,400 lb/hr wood pellets 26,400 lb/hr wood pellets each 26,400 lb/hr wood pellets each
POLLUTION CONTROL EQUIPMENT All particulate collection devices are considered process equipment because the wood dust collected is reused in the process. EMISSION CALCULATIONS Wood Burner/Dryer System Greenova reviewed the stack test report for another wood pellet manufacturer, New England Wood Pellet, and used emission factors developed from that testing to estimate emissions from the wood burner and dryer process. Emissions of NOx, PM10, CO and VOCs were determined based on the stack test results. SO2 emissions were estimated using the emission factor listed in AP-42 Section 1.6, Wood Residue Combustion in Boilers. The maximum capacity of the proposed dryer is 14.43 ODT/hr and 50 MMBtu/hr. The following table summarizes the potential emissions from the burner/dryer. Emission Factor Dryer Emissions
NOx 0.343 lb/ODT lb/hr tpy 4.95 21.68
SO2 0.025 lb/MMBtu lb/hr tpy 1.25 5.48
CO 1.44 lb/ODT lb/hr tpy 20.78 91.01
PM10 0.87 lb/ODT lb/hr tpy 12.55 54.97
VOC 0.274 lb/ODT lb/hr tpy 3.95 17.30
Pellet Coolers The source estimates that 1.0% of the total mass of wood entering the pellet coolers will be emitted as particulate matter. The cyclone efficiency gives an emission factor of 0.3 lb emissions per ton of wood fines into unit. The following calculation shows the particulate emission rate from the pellet coolers: 28,660 lb/hr of wood pellets into cooler * 0.01/2000 lb/ton = 0.143 ton/hr wood fines emitted to the cyclone 0.143 ton/hr into cyclone * 0.3 lb emissions/ton of fines entering unit = 0.043 lb/hr emitted = 0.19 tpy Other Particulate Sources Emissions from the sources that are connected to baghouses were based on the baghouse vendor data that states that particulate matter emissions will be less than 0.02 gr/dscf. The following table shows the potential, controlled emission rates from these sources:
PERMIT APPLICATION REVIEW SUMMARY Facility: Location: AFS #:
Greenova, LLC Berlin 3300790123
Application #:
08-0277
Engineer:
Barbara Dorfschmidt
Date:
8/21/08
Emission Unit Chip storage pneumatic convey system with baghouse Pellet Mill pneumatic convey system and Secondary Hammer Mill with baghouse Dryer fuel pneumatic convey system with baghouse Pellet Cooler and 3 Pellet Mills with multiclone Pellet Packaging with baghouse Pellet Mill Storage Silo with baghouse 2 Pellet Loadout Silos with baghouse
Emission Rate (lb/hr) 0.10 0.82 0.82 0.14 0.01 0.0003 0.004
Page 3 of 5
Potential Emissions (tpy) 0.03 3.57 3.57 0.60 0.03 0.0002 0.008
Facility-wide, potential, controlled emissions of particulates are (54.97 + 2*0.03 + 0.19 + 2*3.57 + 0.0002 + 0.008) = 62.37 tpy. Air Toxics Review The following table details the estimated, uncontrolled emissions of Regulated Toxic Air Pollutants (RTAPs) and Hazardous Air Pollutants (HAPs – identified with an *) from the dryer system. With the exception of formaldehyde and acrolein, RTAP emission factors were taken from AP-42, Table 10.6.2-3 using the following category: “Rotary dryer, green, direct wood-fired, mixed species (40-60% softwood, 40-60% hardwood).” Emission factors for formaldehyde and acrolein were determined from stack test results at New England Wood Pellet. The factors from testing were increased by a safety factor of 50% over the actual test results. Pollutant
CAS #
Acetaldehyde* Acetone Acrolein* Benzene* Crotonaldehyde cis-1,2-Dichloroethylene Formaldehyde* Methanol* Methyl Ethyl Ketone Methylene Chloride* Phenol* Propionaldehyde* Styrene* a-Terpene Toluene* Valeraldehyde m,p-Xylene* o-Xylene* Total HAPs
75-07-0 67-64-1 107-02-8 71-43-2 4170-30-3 156-59-2 50-00-0 67-56-1 78-93-3 75-09-2 108-95-2 123-38-6 100-42-5 8006-64-2 108-88-3 110-62-3 1330-20-7 95-47-6
Emission Factor (lb/ODT – unless otherwise noted) 0.059 0.47 0.0013 0.0047 0.00082 0.0012 0.014 0.059 0.0034 0.0014 0.0079 0.0042 0.00057 0.053 0.0059 0.004 0.0058 0.00058
Maximum Emission Rate (lb/hr) 0.85 6.78 0.02 0.07 0.01 0.02 0.20 0.85 0.49 0.02 0.11 0.06 0.008 0.76 0.09 0.06 0.08 0.008
Potential Emissions (tpy) 3.73 2.97 0.08 0.30 0.05 0.08 0.88 3.73 0.21 0.09 0.50 0.20 0.04 3.35 0.37 0.25 0.37 0.04 10.33
The attached spreadsheet compares the emissions of RTAPs to the de minimus emission rates and adjusted in-stack concentrations listed in Env-A 1400. The uncontrolled emissions of all RTAPs except formaldehyde, acetaldehyde and acrolein, are able to show compliance using either the de minimus or adjusted in-stack concentration method. Formaldehyde, acetaldehyde and acrolein are able to show compliance using a unit impact factor based on air dispersion modeling. MODELING An air dispersion modeling analysis was done by the company’s consultant and reviewed by DES. The analysis shows that
PERMIT APPLICATION REVIEW SUMMARY Facility: Location: AFS #:
Greenova, LLC Berlin 3300790123
Application #:
08-0277
Engineer:
Barbara Dorfschmidt
Date:
8/21/08
Page 4 of 5
the facility will be able to meet all National Ambient Air Quality Standards. See memo dated August 13, 2008 for more details. Unit impact factors for the burner/dryer stack were developed in order to show compliance with air toxics’ AALs. The factors are as follow: 24-hr: 2.169 µg/m3 per 1 lb/hr Annual: 0.223 µg/m3 per 1 lb/hr EMISSION TESTING Because the emissions of CO, NOx, PM10, and VOCs were based on test data from a unit that is similar to but not identical to the Greenova burner/dryer process, emissions testing will be required to verify emission rates. Testing of individual toxic pollutants will not be required at this time because, based on the emission factors used, impacts are estimated to be less than 50% of the AALs. DES may require additional testing in the future if conditions warrant that testing may be needed to verify compliance. COMPLIANCE STATUS Emission Testing – Not applicable. Inspections - Not applicable. Reports – Not applicable. Fees – Not applicable. REVIEW OF REGULATIONS State Regulations Env-A 600 – Permitting • 607.01(c) – Applicable – wood-fired burner > 2 MMBtu/hr • 607.01(n) – Not Applicable – the source is a true minor source • 607.01(v) – Not Applicable – Facility able to show compliance based on potential, uncontrolled emissions Env-A 1200 – Prevention, Abatement, and Control of Stationary Source Air Pollution • 1204.48 - Not Applicable – TPE of VOCs < 50 tpy. • 1211.14 – Not Applicable – TPE of NOx < 50 tpy. Env-A 1400 – Regulated Toxic Air Pollutants • The facility is able to show compliance based on potential, uncontrolled emissions. Env-A 2000 – Fuel Burning Devices • 2002.02 – visible emissions from the wood-fired burner shall not exceed 20% opacity • 2002.08 – emissions of TSP from the burner/dryer shall be limited to 0.30 lb/MMBtu Env-A 2100 – Particulate Matter and Visible Emissions Standards • 2102.04(c)(1) – TSP emissions from all devices other than the burner/dryer shall be limited to an emission rate as calculated by the following formula: E = 4.10P0.67 Where: E = emission rate in pounds per hour; and P = process weight rate in tons per hour • 2103.02 – visible emissions from all non-fuel burning devices shall not exceed 20% opacity.
PERMIT APPLICATION REVIEW SUMMARY Facility: Location: AFS #:
Greenova, LLC Berlin 3300790123
Application #:
08-0277
Engineer:
Barbara Dorfschmidt
Date:
8/21/08
Page 5 of 5
Federal Regulations None applicable. SUMMARY AND CONCLUSION The facility is able to show compliance with all air quality standards based on proposed operations. The only device that is required to be permitted is the wood-fired burner/dryer system. This is due to the fact that the burner exceeds the permitting threshold listed in Env-A 607.01.
