Raymond®

Mechanical Air Separators

Air Preheater CompanyRaymond Operation

Raymond® Mechanical Air Separators

The Raymond® Mechanical Air Sepa-rator produces material with high uni-form fineness; operates in open orclosed circuit; is excellent for de-dust-ing; can provide drying and cooling;and features the unique single ordouble whizzer for faster separationof fines and more positive rejection ofoversize.

Operation CycleMaterial enters the hollow shaft orcenter feed pipe at the top of the sepa-rator and drops upon the rotating dis-tributor plate below. This distributorplace disperses the material into theupward sweep of circulating air devel-oped by the fan in the top chamber ofthe drum. The whizzer blades set upa centrifugal motion of the air and ma-terial. This concentrates the oversizematerial along the surface of the up-per inner cone, where gravity causesit to flow into the lower inner cone andthen out the coarse spout at the bot-tom. The airstream carrying the pow-dered material of required finenessmoves through the fan and is deliveredinto the outer cone chamber where thefines are discharged as finished prod-uct. After the fines are released in theouter cone, the air returns through thedeflector ports to the inner cone, set-ting up a continuous circuit.

In addition to accomplishing fasterseparation of the fines and more posi-tive rejection of the oversize, thewhizzer action is also useful in de-dusting operations-making granularproducts by removing objectionablefines, for example-as well as produc-ing microsize materials with maximumsurface area.

Single Whizzer Air SeparatorsSingle whizzer separators have onlyone bank of whizzer blades to set upcentrifugal action. This unit is ordi-narily used for coarser separations upto approximately 10-15% R74 microns(85 to 90% passing 200 mesh) whichis excellent for de-dusting and raw mixcement operations.

Double Whizzer Air SeparatorsDouble whizzer units have two rowsor banks of whizzer blades. In normaloperations they can produce finishedmaterials up to 0.5-1% R44 microns(99 to 99.5% passing 325 mesh) andin finished cement circuits 2800 to6000 Blaine or masonary cements.

Fineness ControlBoth the single and double whizzerunits in 4 and 6 foot diameter sizesare equipped with vertical slide damp-ers which allow external fineness ad-justment while the unit is in operation.For precise fineness control, all units8 foot diameter and larger are providedwith special vertical swing dampers toincrease their efficiency and versatil-ity when separating in the minus 325mesh and subsieve size range. Onmany materials, finished products witha high percentage passing 15 to 20microns can be obtained without diffi-culty.

Raymond® mechanical air separatorsare built in eleven sizes ranging from4 feet to 24 feet in diameter, as wellas a 30 inch unit for small capacitiesand test runs. Each size is availablein a single or double whizzer construc-tion. A special 10 inch laboratory sepa-rator completes the Raymond line andprovides a useful machine for handlingsmall lots of materials in experimen-tal work.

Typical ApplicationsCement - classify and dry raw

mix, and to classify and cool finishcement.

Limestone - produce limestonesand to meet the close specificationsrequired for use in bituminous con-crete, mortar, aggregate and manysimilar uses.

Flour Mixes - make fine, uniformcake mixes and for production of pro-tein-enriched grades of flour.

Hydrated Lime - produce a high-fineness, uniformly-classified hydratedlime for chemical and spray purposes.

Food Products - classify variousfood products including sugar, cocoa,milk powder, food mixtures,cornstarch, wheat starch and soybeanmeal.

Chemicals - make various gradesranging from extremely fine to thegranular, dust-free gradation, such assoda ash and sodium phosphate.

Talc and Clays - upgrade the qual-ity of such materials as talc,kaolin,clays and phospate rock byremoving such impurities as silica, flintand other foreign materials.

Metal and Metallurgical Powders- classify metal powders consisting ofcopper, bronze, iron and various al-loys. De-dusting of sea-coal forfoundry-facing in another typical ap-plication.

Produce Materials with High Uniform Fineness

The Air Preheater Company,Raymond Operations continues inits commitment of providing ourcustomers with the best productsand service in the industry.

For additional information, contactyour local Raymond Operations’sales office.

Construction and Specifications

Standard construction of theRaymond® mechanical air separatorincludes cast, abrasion resistantwhizzer cones and replaceable steel-plate liners on the inner cone.

The distributor plate is protected withspecial liners along the outer edgewith a cone at the center to providefurther protection and insure even flowof the incoming material off thedisbributor plate at the start of classi-fication.

Separators for handling abrasive ma-terials can be equipped with specialabrasion resistant liners in all parts ofthe machine.

All mechanical air separators are pro-vided with a vent connection in thecone section as standard construc-tion for removing infiltrating air andkeeping the unit under negative pres-sure for dust free operation.

The 4 and 6 foot diameter Raymond®

mechanical air separators are built onthe same principle as the larger unitsbut are arranged with a vertical motordrive. This eliminates the need for agear and pinion.

eziSthgieWetamixorppA

gkblH-thgieH

mmtfh-thgieHmmtf

D-retemaiDmmtf

"03 059 004 2.5 005,1 5.1 004 2.3 009

'4 000,2 009 0.8 004,2 3.4 002,1 0.5 005,1

'6 000,4 008,1 0.11 003,3 8.5 007,1 1.7 001,2

'8 000,8 006,3 3.41 003,4 7.7 003,2 7.9 009,2

'01 005,11 002,5 8.61 001,5 5.8 005,2 7.11 005,3

'21 005,22 002,01 7.91 009,5 7.9 009,2 2.41 003,4

'41 005,82 009,21 1.22 007,6 3.01 001,3 0.61 008,4

'61 003,93 008,71 5.52 007,7 1.21 006,3 8.71 004,5

'81 008,44 003,02 1.72 002,8 9.11 006,3 8.02 003,6

'12 004,96 004,13 3.92 009,8 9.41 005,4 0.42 003,7

'42 000,09 008,04 3.73 003,11 2.71 002,5 0.72 002,8

Inner Drum Top Plate

Whizzer Blades

Top Plate Door

Distribution Plate Assembly

Vent Pipe Connection

Whizzer ConesInner Drum

Top Plate

Outer DrumOuter Drum Liners

Vertical SwingDamper Assembly

Outer Fan Blade

Inner Drum Liner

Whizzer PlatesInner Drum Door

Outer Drum Door

Deflector

Lower Inner Cone

Upper Outer Cone

Lower Outer Cone

Coarse Valve(If required)

Double Whizzer Separator

Fines

Inner Cone Liners

Hh

D

ALSTOM Power, Inc., Air Preheater Co., Raymond Operations, 4525 Weaver Pkwy., Warrenville, IL 60555 USAToll Free: 877.661.5509 - Tel: 630.393.1000 - Fax: 630.393.1001

E-mail: info@airpreheatercompany.com - Website: www.airpreheatercompany.com

Product Bulletin 3603-1

Applications

Closed Circuit GrindingWhen operated in closed circuit com-bination with a pulverizer, the separa-tor skims off the fines as fast as theyare made so the mill works only onfresh material without wasting power.The tailings are discharged back tothe mill for further reduction. Thereground material is returned to theseparator with the feed, so that a con-stant circulating load is set up be-tween the mill and the separator.

The separator may be used in combi-nation with ball mills, tube mills andcompartment mills. Its function is tomaintain a constant fineness indeliverying the finished product.

It saves power in the overall operationand increases the capacity of the com-plete unit.

The advantages of using a Raymond®

mechanical air separator in closed cir-cuit with the grinding mill for produc-ing closely sized finished productsinclude:

1. Positive control of fineness or sur-face area and the elimination of over-size particles.2. Convenient variation of productfineness-vertical dampers permit widerange changes in fineness, externallywhile the separator is in operation.3. Increase in the output capacity ofthe grinding mill. Experience hasshown increases from 25 to 75% ormore.4. Lowering the temperature of themill and product.5. Improvement in grind efficiency,as in the case of ball mills where ballcoating with fine material can reducegrinding ball effectiveness.

Internal Air Flow System forDrying and CoolingEffective drying within the separatoris normally limited to those installa-tions where the separator is used inclosed circuit with a grinding unit. Theoversize particles with entrained mois-ture, rejected in the first pass ascoarse, are further reduced in thegrinding mill to permit efficient dryingin the second pass through the sys-tem.

Cooling in separators is also a wide-spread practice in classifying finishedcement.

Both the single and double whizzerunits can be provided with cooling anddrying auxiliaries which consist of upto four inlet openings in the drum sec-tion and two air outlets in the conesection. Water jackets can also beprovided on the cone sections for usein cooling finished cement on sizes18’ through 24’ diameter.

Open CircuitIn some cases, it is convenient to in-stall the separator independently fromthe mill to make both a fine and coarseproduct simultaneously.

Raymond® Mechanical Separator inOpen Circuit System

Feed

Separator

Coarse

Fines

Raymond® Mechanical Separator inClosed Circuit System

Circulating Load

Separator

Grinding Mill

Raw Feed

Fines

Coarse