1. UTILIZATION OF BOOSTER FANS IN UNDERGROUND COAL MINES
Felipe Calizaya
Michael G. Nelson
Jessica Wempen
Randy Peterson
University of Utah, Salt Lake City, UT
2011

2. INTRODUCTION Booster Fan:
An underground fan installed in the main air stream to handle the quantity of air circulated through a section
Installed in a permanent bulkhead and equipped with a set of airlock doors and fan monitors
A properly sized and sited booster fan can be used to create safer work conditions and allow the extraction of minerals from great depths

3. Daw Mill Colliery
Daw Mill Colliery is the most significant coal mine in the UK producing 3 million tonnes per year
The mine is deep and extensive with a depth over 850 m and over 7.5 km of workings
A retreating longwall is used as the primary means of production
Longwall panels are developed with a single entry. Panels are 2,500 m long and 350 m wide
Isolation pillars from 90 to 180 m wide are left between each panel

4. Daw Mill Colliery Ventilation
One intake shaft and one exhaust shaft
A surface drift used to transport coal provides 20 m3/s of intake air
Two exhausting centrifugal surface fans are installed on the surface. One fan is active and one fan is redundant
Both surface fans are capable of operating at 169 m3/s with a pressure of 2.8 kPa
Production headings are ventilated with at least 6.5 m3/s, this is driven by a 90 kW auxiliary fan operating at 3.5 kPa

5. Daw Mill Colliery Ventilation
One booster fan site that consists of four 2 m axial booster fans with a combined capacity of 120 m3/s with a pressure of 3.5 kPa
Inlet
Outlet
a) Inlet Side S F
a) Cross-section View
b) Long -section View

6. Daw Mill Colliery Ventilation
Booster fans are located in the return and the motors are enclosed in flame proof housing
Because of the risk of spontaneous combustion booster fans were installed in rock above the coal seam
Booster fans are sited inby the current neutral ventilation point so there is a small amount of air recirculation (less than 10%)
Booster fans are essential to provide adequate air volume and control heat. The fans increase the volume of air at the longwall face by 50%

7. Daw Mill Colliery Ventilation
Ventilation challenges include:
Methane – 2 m3 of methane per ton of coal
Spontaneous combustion – can occur regularly during development and salvage operations
Changed hyphens to en dashes, with a space on either side, to match other slides that use dashes.

8. Daw Mill Colliery Ventilation
Methane and carbon monoxide levels are measured throughout the mine
At the booster fans airflow, pressure, vibration, bearing temperature, methane, and carbon monoxide are constantly monitored
In addition to electronic monitoring, a tube bundle system is used to monitor air quality
Because of the high risk of spontaneous combustion a nitrogen system is used

9. Maltby Colliery
Maltby Colliery produces 3 million tons per year ROM and 1 million tons per year clean coal
A retreating longwall is used as the primary means of production and is supported by four development sections
Longwall panels are developed with a single entry system
The mine is deep and extensive with a depth over 960 m and over 8 km of workings

10. Maltby Colliery No.1 SHAFT No.2 SHAFT No.3 SHAFT. 1911-1972
SEAM EXHAUSTED
AFTER 61 YEARS
DEPTH IN
METRES.
BARNSLEY SEAM
WORK BEGAN 1970
SEAM ABANDONED
1993.
812m
SWALLOW WOOD SEAM
822m
HAIGH MOOR SEAM
SEAM PARTIALLY
WORKED LATER
ABANDONED.
CURRENT
WORKINGS
960m
PARKGATE SEAM
THORNCLIFFE SEAM
982m

12. Maltby Colliery Ventilation
Two intake shafts and one exhaust shaft
Two 5.3 m centrifugal exhaust fans are installed on the surface. One fan is active and one fan is redundant
Both fans are capable of operating at 280m3/s with a pressure of 5.5 kPa.

13. Maltby Colliery Ventilation
One 2.05 m axial booster fan operating at 140 m3/s with a pressure of 7.4 kPa
Bulkhead
Screen
Impeller
Airflow
Motor
Diffuser
Drift Floor
Section View

14. Maltby Colliery Ventilation

15. Maltby Colliery Ventilation
Ventilation challenges include:
Heat – Virgin rock temperature is near 42⁰C and air picks up an additional 7 ⁰C across the booster fan
Humidity – High water usage for dust control and machine cooling
Methane – 25 m3 of methane produced per ton of coal
Frictional Ignition

16. Maltby Colliery Ventilation
Booster fan is located in the return and the motor is enclosed in flame proof housing
Booster fans are essential to provide adequate air volume and control heat
Booster fan is sited inby the current neutral ventilation point so there is some air recirculation
Methane drainage system is used to control excess methane

17. Maltby Colliery Ventilation
Booster fan installation includes four airlock doors between the intake and the return. Three airlock doors are used in the fan bulk head
A manometer and a digital pressure gauge are used to measure pressure across the bulk head
The installation includes a water barrier to control fire that may occur at the fan

18. Maltby Colliery Ventilation
Methane is monitored in the intake and in the return upstream and downstream from the fan
Carbon monoxide and smoke detectors are located downstream
A tube bundle system is also used to monitor the air quality

19. Maltby Colliery Ventilation
To Tail Gate
Man Doors
Bulkhead
Return
Booster Fan
Airlock Doors
Intake
Fan and Environmental Monitors
Tube Bundle
Carbon Monoxide
Smoke
Methane
Manometer
Delta Press

20. Kellingley Colliery
Kellingley Colliery produces 2.3 million tons per year
A retreating longwall is used as the primary means of production and is supported by four development sections
Longwall panels are developed with a single entry system
The mine is deep and extensive with a depth over 800 m and over 9 km of workings

21. Kellingley Colliery Ventilation
One intake shaft and one exhaust shaft
Two 4.14 m centrifugal blowing fans are installed on the surface. One fan is active and one fan is redundant
Both fans are capable of operating at 290 m3/s with a pressure of 2.5 kPa.

22. Kellingley Colliery Ventilation
Three booster fan sites all located in the return
Single 1.6 m double inlet centrifugal fan operating at 290 m3/s and7 kPa
Four 1.2 m axial fans operating at 68 m3/s and 2.5 kPa, two installations one in the return and one in intake

23. Kellingley Colliery Ventilation
Bulkhead
Casing
Diffuser
Inlet
Discharge

24. Centrifugal Booster Fan

25. Kellingley Colliery Ventilation
Intake
Bulkhead
Booster Fan
Return
Airlock
Doors
Airlock Doors
Fan and Environmental Monitors
Methane
Carbon Monoxide
Delta Press
Temperature

26. 2 x 2 Booster Fans
Intake
Airlock Doors
Bulkhead
Return

27. Kellingley Colliery Ventilation
Ventilation challenges include:
Methane, Heat, and Dust
Booster fans are essential to provide adequate air volume and control heat
There is a small amount of air recirculation (less than 10%)
Turbulence around the multi-fan installation can be a problem

28. Significant Differences in Ventilation Practices Between the UK and the US
Booster fan installations are common and are accepted as a safe and effective means of ventilating sections
Booster fans are often viewed as the only option for providing adequate ventilation underground
Booster fans are most commonly axial fans installed in clusters with up to four-two stage fans per site and all fans were installed in concrete bulk heads
Booster fans were selected based on each mines pressure and quantity requirements

29. Significant Differences in Ventilation Practices Between the UK and the US
Two types of parameters were monitored at each fan: fan parameters and environmental parameters
Fan parameters included differential pressure, motor and bearing temperatures, and air velocity
Environmental parameters included methane, carbon monoxide, and smoke. Atmospheric monitoring systems were extensive and robust
Booster fans were most often located in the returns in series with the main fans
Motors and electrical components were located in the return but were contained in flame proof housing

30. Significant Differences in Ventilation Practices Between the UK and the US
There was no electrical interlocking between the main fans and the booster fans at any of the mines
All of the coal mines were using single entry systems with barrier pillars between the longwall panels
No neutral entry for the conveyor belts were used. Belts were used in both intake and in return airways
Recirculation and series ventilation are not strictly prohibited. Most mines using booster fans were recirculation about 10% of the air

31. Booster fan model for Highland 9 Mine

32. Highland Mine projected ventilation network using only a main fan
Unit 3: 9.4 cms
Unit 5: 9.4 cms
North Mains
Summary of Results:
Main fan duty: m3/s at
2.24 kPa
Total airpower: kW
West Mains
Mined Out Area
Unit 1: 9.4 cms
East Mains
Unit 2: 9.4 cms
Legend
Main Fan
North
Unit 4: 9.4 cms

33. Highland Mine projected ventilation network using one booster fan
Unit 3: 9.4 cms
Unit 5: 9.4 cms
North Mains
Summary of Results:
Main fan duty: m3/s
at 1.37 kPa
Booster fan duty: 150 m3/s at kPa
Total airpower: kW
West Mains
Mined Out Area
Unit 1: 9.4 cms
East Mains
Unit 2: 9.4 cms
Legend
Main Fan
North
Booster Fan
Unit 4: 9.4 cms

34. Highland Mine projected ventilation network using two booster fans
Unit 3: 9.4 cms
Unit 5: 9.4 cms
Summary of results:
Main fan duty: m3/s at
1 kPa
Booster fan m3/s at
duty kPa
Booster fan 2 : 65 m3/s at
Total airpower: kW
North Mains
West Mains
Mined Out Area
Unit 1: 9.4 cms
East Mains
Unit 2: 9.4 cms
Legend
Main Fan
Booster Fan 1
North
Booster Fan 2
Unit 4: 9.4 cms