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Niagara Development - Utility Assets

Utilities Department


Steam Production

The New Page mill has (4) four 75,000 lb per hour coal fired power boilers (located in building 45) that produce process steam for drying paper, heating water, heating the buildings and producing power. Coal is delivered by truck from the Escanaba lakefront dock to an on-site storage yard, which has a 10,000 ton storage capacity.  The coal is then processes through a crushing and screening system (located in building 97), where it is sized for use dependent on the boiler being supplied (stoker or pulverized coal fired).  Two of the four boilers also have the ability to burn wood waste as a supplemental fuel.  Wood waste is produced on-site in the PGW fiber pulping process and also purchased locally.  All four boilers are ducted through a common state of the art electrostatic precipitator (building 90) and electrostatically enhanced baghouse to control particulate emissions.  The baghouse was installed in 2006 at cost of 7.5 million dollars and is considered the best available control technology (BACT) for particulate matter control.


Boilerhouse (Building 45)
Power Generation

Power generation is accomplished with two steam turbine generators (located in building 20) that have a combined power output of 13 megawatts.  #1 generator is a 3 megawatt Westinghouse backpressure unit with a 125 psi exhaust.  #2 generator is a 10 megawatt General Electric unit with a 50 psi extraction and a final stage condensing unit.  The resulting 50 and 125 psi exhaust steam is used in the paper making process.

Filtered Water

The Menominee River is the main source of water for the paper mill. A pumping station (located in building 57) draws water from the river and pumps it to the water filtration plant (located in building 56) where it is treated for suspended solids and color.  The plant capacity is approximately 7.2 million galloons per day.

Filtration Plant (Building 56)
 

Waste Water Treatment

Waste water is treated by means of two different processes.  An aerobic facility (buildings 89, 93, and 104) treats low BOD process waters at a maximum average capacity of 8 million gallons per day.


Aerobic Treatment (Buildings 89, 93, and 104)


An anaerobic treatment facility (building 99) pre-treats high BOD process waters at a rate of 1.5 million gallons per day.  Solids from the treatment facility’s are concentrated using two Andritz presses (building 103) and then spread on local farming land.


Anaerobic treatment (Buildings 99 and 103)

Utility Department process details

Steam Generation

Typical Monthly Totals

Total steam produced:  132.4 mm lbs.

Boilerhouse auxiliary:  12.4 mm lbs.

Steam turbines:  24.3 mm lbs.

Process:  95.7 mm lbs.

#1 Boiler

1939 combustion engineering water tube boiler

Steaming capability
 -75,000 lb/hour 80% efficient (coal)
 -450 lb. steam @ 675 deg.

Fuel used – pulverized coal
 -15,000 tons of coal per year
 -2 – CE Raymond 372 bowl mills
 -New Ro type burners in 1996
 -6” wide x 10’ long x 8’ tall dutch ovens that burn 14,250 tons of bark per year
 -Bark produces 30 to 35 K/Lb/hour
 -wood waste:  70% efficient
 -2 five million BTU natural gas ignitors for lighting off the coal

#2 Boiler

1939 combustion engineering water tube boiler

Steaming capability
 -75,000 lb/hour 80% efficient
 -450 lb. steam @ 675 deg.

Fuel used – pulverized coal
 -15,000 tons of coal per year
 -One CE-Raymond 453 bowl mill
 -Installed in 1997
 -New Ro type burners in 1996
 -2.6’ wide x 10’ long x 8’ tall dutch ovens that burn 14,250 tons of bark per year
 -Bark produces 30 to 35 K/Lb/hour
 -Wood waste:  70% efficient
 -2 five million BTU natural gas ignitors for lighting off the coal
 
#3 Boiler

1948 combustion engineering water tube boiler

Steaming capability
 -75,000 lb/hour 85.5% efficient
 -450 lb steam @ 675 deg.

Fuel used – pulverized coal
 -27,000 tons of coal per year
 -CE Raymond 453 bowl mill
 -DCS Bailey Infi 90 installed in 1999
 -2 five million BTU natural gas ignitors for lighting off the coal

#4 Boiler

1963 Babcock & Wilcox Detroit rotograte stoker

Steaming capability
 -75,000 lb/hour 86.1% efficient
 -450 lb steam @ 675 deg.

Fuel used – 1 ¼” x 3/8” stoker coal
 -Coal fed into boiler by three Detroit rotograte stokers
 -23,000 tons per year

Controls

All boilers and auxiliaries are controlled by a Bailey DCS system
 -#2 boiler in 1997
 -Auxiliaries in 1998
 -#1 boiler in 1998
 -#4 boiler in 1998
 -#3 boiler in 1999
 
Coal Crusher

Designed to run 50 tons per hour of run of mine coal (6” x 0” or 5” x 3/8”)

Gunlach Machine Company double stage crusher

Coal crusher building

Crushes the coal into two categories (2” x 1 ¼” and 3/8” x 0”)

All coal is sent to a double deck vibrating screen where the sizing takes place

Stoker coal 1 ¼” to 3/8” goes to #4 boiler

Coal 2” to 1 ¼” and 3/8” to 0” goes to pulverized coal boilers #1-2-3

Stocker coal pile – 8,724 tons

Stoker coal is stored in a 60 ton silo until use

Coal storage area can hold 10,000 tons of coal

Coal Specifications

Heating value – 13,000 BTU/lb. (min 12,500 BTU/lb)

Ash content – target 7.5% maximum 8.5%

Moisture – 5% maximum

Sulpher range – 0.8% to 1.8%, 2% maximum at 13,000 BTU/lb.

Grind – 50 to 55 HGI

Volatile matter – 35% to 38% based on fuel specification

Fixed carbon – 19% to 52% based on fuel specification

Ash fusion – target 2,300 Deg. F ID

Bark Handling System

Drag type conveyor system that handles 14 tons of bark per hour

All of the woodbark (15,000 tons/year) that is blown to us, plus what we receive from an outside supplier (42,355 tons/year)

All wood waste is burned in boilers #1 & 2 dutch ovens

Produce 30 to 35 K/Lb/hr in each boiler from wood wastes

3.15 pounds of steam per pound per bark

Ash Handling System

Two ash silos

South silo
 -Unloader is rotary drum type (1962)
 -Collects ash from all 4 boilers
 -Bark furnaces back end and fly ash
 -Dry ash handling system

North ash silo
 -Unloader is from United Conveyor Model 1535/45 twin paddle mixer
 -Ash comes from the precipitator, ash hoppers under each field
 -Dry ash handling system

All ash hauled to a company owned solid landfill site

Precipitator

1974 electrostatic precipitator with one common stack from all four boilers

Four fields have weighted wires in the first three fields


Fourth field installed in 1997 with riged discharge electrodes
 -Controlled by a precip-tech SQ-300 automatic voltage controllers
 -Efficiency is 99.8% at zero opacity