Dust Control Handbook for Industrial Minerals Mining and Processing

More documents

Recommendations

Info

Fan TypesThere are two basic types of fans: axial-flow fans and centrifugal fans. There are also other fandesigns that use or combine the concepts of axial or centrifugal flow; these are axial-centrifugalfans and roof ventilators. Again, the selection of the fan type is based upon the requirements ofthe ventilation system design.Axial-Flow FansThe axial-flow fan category includes propeller fans, tubeaxial fans, vaneaxial fans, and two-stageaxial-flow fans. Axial flow fans move the air in a direction that is "axial" or parallel to the axisof rotation of the fan. Propeller fans are the most common type. They are generally mounted inthe wall of the building near a heat source to exhaust the hot air into the outside atmosphere(Figure 1.28). They can have different drive configurations, being either direct drive or beltdrive. The wall-mounted fans can also be constructed with shutters that close when the fan isturned off. Propeller fans are designed to move large volumes of air at low static pressures[Bleier 1998].Figure 1.28. Wall-mounted propeller fan.Tubeaxial fans are used for exhausting air from an inlet duct (Figure 1.29, left). They consist ofa fan with many blades in a cylindrical housing. The blades are generally shaped as an airfoil tohelp with air movement. The hub diameter can be 30 to 50 percent of the blade outside diameter[Bleier 1998]. The housing is connected to the inlet duct and also contains the motor support.These fans are used in conditions that require moderate static pressures (higher than thoserequired for propeller fans).Fundamentals of Dust Collection Systems 53
Vaneaxial fans are similar to tubeaxial fans. The vaneaxial fan has a housing that contains guidevanes that are oriented parallel to the airflow (Figure 1.29, right). These vanes are used torecover the tangential airflow velocity from the fan blade to convert it into static pressure. Thistangential airflow velocity is not recovered as static pressure in propeller or tubeaxial fans (thiscomponent is lost energy). The hub diameter of a vaneaxial fan is much larger being 50 to 80percent of the blade outside diameter [Bleier 1998]. The vaneaxial fan is used for high staticpressure conditions.Figure 1.29. Typical tubeaxial fan (left) and vaneaxial fan (right).Two-stage axial-flow fans are basically two axial flow fans configured in series. Thisconfiguration allows for operation in high static pressure conditions as each fan's operatingpressure is added together when in series. This fan can be designed to have each fan rotate in thesame direction with guide vanes located between each of the fans, or the fans may counter-rotate.Centrifugal FansThe airflow for a centrifugal fan is different from that of axial flow fans. For a centrifugal fanthe airflow is drawn into a rotating impeller and discharged radially from the fan blade into ahousing. The resulting flow of air is perpendicular to the axial rotation or parallel to blademotion [Hartman 1997] and the housing is used to direct the airflow to the desired location(Figure 1.30).54 Fundamentals of Dust Collection Systems
Page 2 and 3:
Report of Investigations 9689Dust C
Page 4:
FUNDAMENTALS OF DUSTCOLLECTION SYST
Page 7 and 8:
Minimizing Field Fits and Welds ...
Page 9 and 10:
Recommendations for Proper Wet Dril
Page 11 and 12:
CONTROL TECHNOLOGIES FOR FILLING 50
Page 13 and 14:
Effective Filtration ..............
Page 15 and 16:
ILLUSTRATIONSFigure 1.1. Relationsh
Page 17 and 18:
Figure 3.2. The air and water flow
Page 22:
Figure 9.5. Problem created by heat
Page 25 and 26:
UNIT OF MEASURE ABBREVIATIONSUSED I
Page 28:
Robert J. Franta, Quotation Enginee
Page 32 and 33: silica. Quartz is the most common s
Page 34 and 35: DUST CONTROL HANDBOOK FOR INDUSTRIA
Page 36 and 37: CHAPTER 1: FUNDAMENTALS OFDUST COLL
Page 38 and 39: The shape of particles affects how
Page 40 and 41: EXHAUST SYSTEMS DESIGNAll exhaust s
Page 42 and 43: stripping, which allows workers to
Page 44 and 45: When using the air quantities in Ta
Page 46 and 47: X = distance in feet from the face
Page 48 and 49: Checklist for Hood EffectivenessThe
Page 50 and 51: A major disadvantage of the high-ve
Page 52 and 53: A common misconception when designi
Page 54 and 55: Avoiding Mitered Elbows Greater Tha
Page 56 and 57: Figure 1.13. Depiction of the horiz
Page 58 and 59: Figure 1.14. Typical design of grav
Page 60 and 61: Baghouse CollectorsBaghouse dust co
Page 62 and 63: Table 1.2. Emission factors for cru
Page 64 and 65: Figure 1.17. Typical design of a me
Page 66 and 67: Reverse Jet (Pulse Jet) CollectorsR
Page 68 and 69: Figure 1.20. Cartridge collector wi
Page 70 and 71: Wet scrubbers are particularly adva
Page 72 and 73: Electrostatic precipitators normall
Page 74 and 75: may be related to specific applicat
Page 76 and 77: times. When considering the depth o
Page 78 and 79: Figure 1.25. Demonstration of how a
Page 80 and 81: Figure 1.26. A typical fan performa
Page 84 and 85: Figure 1.30. Typical centrifugal fa
Page 86 and 87: Figure 1.32. Typical roof ventilato
Page 89 and 90: DUST CONTROL HANDBOOK FOR INDUSTRIA
Page 91 and 92: The vast majority of dust particles
Page 93 and 94: Table 2.1. Particle/droplet size in
Page 95 and 96: Air Atomizing NozzlesAir atomizing
Page 97 and 98: Hydraulic Flat Fan NozzlesFigure 2.
Page 99 and 100: for dust knockdown or suppression,
Page 101 and 102: Nozzle MaintenanceFigure 2.14. Typi
Page 103 and 104: Accidental DamageInadvertent harm t
Page 105 and 106: NDT Educational Resource Center, Io
Page 107 and 108: 78 Wet Spray SystemsDUST CONTROL HA
Page 109 and 110: contains a piston which delivers ha
Page 111 and 112: produce an increase in the penetrat
Page 113 and 114: Dry DrillingDry drilling is accompl
Page 115 and 116: Circular ShroudIn contrast to the u
Page 117 and 118: The collector airflow has a more su
Page 119 and 120: Air-Blocking ShelfThe air-blocking
Page 121 and 122: dust emissions from mast lowering,
Page 123 and 124: This simple procedure of creating a
Page 125 and 126: Figure 3.15. Air ring seal used to
Page 127 and 128: Figure 3.17. Illustrations showing
Page 129 and 130: unsubstantiated due to the inconsis
Page 131 and 132: safety considerations may preclude
Page 133 and 134:
Figure 3.22. A filtration unit, loc
Page 135 and 136:
Miller S, Emerick JC, Vogely WA [19
Page 137 and 138:
USBM [1995]. The reduction of airbo
Page 139 and 140:
110 Drilling and BlastingDUST CONTR
Page 141 and 142:
Wet Control MethodsPREVENTION AND S
Page 143 and 144:
Figure 4.2. Examples of compressive
Page 145 and 146:
Figure 4.5. Illustration of a dry (
Page 147 and 148:
Figure 4.6. Illustration of a dry (
Page 149 and 150:
Wet dust control methods for crushi
Page 151 and 152:
Work Practices to Minimize Dust Exp
Page 153 and 154:
Some specialty grinding operations
Page 155 and 156:
should be frequently inspected for
Page 157 and 158:
Open screen decks slowly to allow i
Page 160 and 161:
DUST CONTROL HANDBOOK FOR INDUSTRIA
Page 162 and 163:
CHAPTER 5: CONVEYING AND TRANSPORTT
Page 164 and 165:
Figure 5.3. Basic depiction of mate
Page 166 and 167:
that the material falls before land
Page 168 and 169:
Figure 5.10. Skirtboard used within
Page 170 and 171:
CarrybackMaterial that sticks or cl
Page 172 and 173:
CONVEYOR DESIGN AND MAINTENANCE ISS
Page 174 and 175:
Figure 5.15. Conveyor transfer encl
Page 176 and 177:
High-volume, high-pressure sprays s
Page 178 and 179:
Figure 5.19. Depiction of a bucket
Page 180 and 181:
Figure 5.21. Depiction of two types
Page 182 and 183:
Figure 5.25. Venturi eductor utiliz
Page 184 and 185:
Page 186 and 187:
CHAPTER 6: BAGGINGThis chapter disc
Page 188 and 189:
caused during manufacturing, includ
Page 190 and 191:
Overall PerforationsThe use of over
Page 192 and 193:
Figure 6.5. Open-top bag being load
Page 194 and 195:
Bagging operators should be aware t
Page 196 and 197:
Figure 6.8. Exhaust hood to capture
Page 198 and 199:
In the original design, a single no
Page 200 and 201:
The OASIS is a relatively simple de
Page 202 and 203:
Figure 6.13. Bag storage shelves sh
Page 204 and 205:
Figure 6.14. Bag and belt cleaner d
Page 206 and 207:
other industrial application using
Page 208 and 209:
The robotic arm automatic palletize
Page 210 and 211:
For many years, this plastic wrappi
Page 212 and 213:
warehouse location until a later ti
Page 214 and 215:
used successfully to perform this c
Page 216 and 217:
Page 218 and 219:
CHAPTER 7: BULK LOADINGDuring the b
Page 220 and 221:
Figure 7.2. Loading spout discharge
Page 222 and 223:
Cascading Loading SpoutFigure 7.5 i
Page 224 and 225:
a seal at the entry and exit points
Page 226:
REFERENCESBiere G, Swinderman RT, M
Page 229 and 230:
200 Bulk LoadingDUST CONTROL HANDBO
Page 231 and 232:
many years, as well as some new and
Page 233 and 234:
Figure 8.2. Air spray manifold desi
Page 235 and 236:
Figure 8.3. Test subject wearing po
Page 237 and 238:
Spills of product material are a co
Page 239 and 240:
epetitive dust leaks should not sim
Page 241 and 242:
Effective Upward Airflow PatternThe
Page 243 and 244:
Figure 8.8. Open-structure design c
Page 245 and 246:
manually removing the bags and plac
Page 247 and 248:
Figure 8.12. Increase in worker’s
Page 249 and 250:
In other cases, an operation may wa
Page 251 and 252:
Cecala AB, O'Brien AD, Pollock DE,
Page 253 and 254:
224 Controls for Secondary SourcesD
Page 255 and 256:
where C o = outside respirable dust
Page 257 and 258:
minimal improvement in the cab's ai
Page 259 and 260:
RECOMMENDATIONS FOR FILTRATION/PRES
Page 261 and 262:
Effective FiltrationFigure 9.4. Res
Page 263 and 264:
average decay times were between 16
Page 265 and 266:
Figure 9.6. Filtration unit showing
Page 267 and 268:
This table highlights a number of c
Page 269 and 270:
NIOSH [2001b]. Technology news 486:
Page 271 and 272:
Page 273 and 274:
upon the wind velocity (or disturba
Page 275 and 276:
Maximum size is the largest particl
Page 277 and 278:
Figure 10.4. Use of end-dumping wit
Page 279 and 280:
conditions. Performance of each of
Page 281 and 282:
A water truck, used to apply water
Page 283 and 284:
Surfactants work by reducing the su
Page 285 and 286:
which differed for the various site
Page 287 and 288:
Figure 10.9. Self-tarping dump truc
Page 289 and 290:
percent [Fryrear and Skidmore 1985]
Page 291 and 292:
Figure 10.12. The armoring process
Page 293 and 294:
A current method of stockpile forma
Page 295 and 296:
Figure 10.15. Demonstration of how
Page 297 and 298:
Chekan GJ, Cecala AB, Colinet JF [2
Page 299 and 300:
Midwest Research Institute [1981].
Page 302 and 303:
Page 304 and 305:
GLOSSARYAbrader. An implement used
Page 306 and 307:
Carryback. Material that sticks or
Page 308 and 309:
End-dumping. A process of spreading
Page 310 and 311:
Open structure building design. A p
Page 312 and 313:
Table bushing. A bushing used to se
Page 314:
Delivering on the Nation’s promis
show all

Dust Control Handbook for Industrial Minerals Mining and Processing

Create successful ePaper yourself

Delete template?

Save as template?