05 Separating

Grinding with ball mill s l systems Separating Separating 2 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separating process ss FR Air 3 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Mechanical air separat (1st generation) eparator 4 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Cyclone air separator ( nd generation) rator (2 External fan Dedusting High efficiency cyclones Z ZUB, Cyclopol types 5 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Rotor cage separator ( rd generation) rator (3 4 6 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separation in 3rd Gene Generation Separator Basic function: Feed eed  Material enters the separator at Centrifugal orces Centrifu al Forces the top.  ir stream is generated by external fan. and guide anes. ines are sucked in. Coarse particles are accelerated by rotor and stopped by guide anes, where they slip down and lea e the casing at the bottom.  Material falls down between rotor Air ir Guide vanes uide anes Turnin cage rotor urning ca e Air ir  ine material exits with airflow at the lower/upper part of the casing the rotational speed of rotor. 7 SEPT-07 Returns eturns Source: Chr. Pfeiffer QDK Separator Air with fines ir ith  Product fineness is adjustable by HGRS Tikaria_Mill W Mill Workshop What is the separating efficiency dependent on? rating  Material:  fineness eed ( ) ines ( ) Tromp cur e p A - Return (R)   mount of feed eed distribution V F  Air: Volume (V [m3/h])  Distribution  The fineness relationship mi ip mill filter / separator fines  R 8 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Possible causes that li limit the separating efficiency The typical situations for 3rd generation separators are: s  Une en airflow and/or fe d/or feed distribution to the rotor  Reduced separating airf ng airflow due to:    Separator fan damper (o speed) not at maximum per (or an nominal too low ow Limited rotor speed due to mechanical problems or d insufficient nominal cap al capacity of the motor and/or gear box  Contamination of the fin by coarse product fines  Separator fines much fin than final product uch finer 9 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Tromp cur e key param parameter Tromp value [%] 100 Separator fines es Separator return Bypass Bypa HGRS Tikaria_Mill W Mill Workshop [Qm] 10 SEPT-07 Tromp cur e key param parameter Tromp value [%] 100 Coarse in fines Separator fines es Separator return Bypass Bypa HGRS Tikaria_Mill W Mill Workshop [Qm] 11 SEPT-07 Amount of material  Circulating load: A, & R en [t/h] A= +R  Circulating load factor: u= A F V [-] A F R 12 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separator performance (1/2) mance .0 . .0 . Circ la ing loa fac or [-] High igh .0 Norm al 3. 3.0 2. 2.0 1. 1.0 2' 00 Low 3'000 3' 00 '000 C m n fin n ' 00 [cm2/g] '000 ' 00 '000 13 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separator performance (2/2) mance 50 45 40 Hig h p o ten tia l 35 30 By pass [%] Med iu m p o ten tia l 25 20 15 10 5 0 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 Lo w p o ten tia l Circulating load factor u [-] 14 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Air olume  Separator specific feed load Asl = A V Asl < 2.5 [kg/m3]  Separator specific fines load s Fsl = F V Fsl < 0.7 [kg/m3] F X 1¶000 [kg/m [kg/m3] V X 1¶000 [kg/m [kg/m3] A R 15 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Air distribution FR A ir  Lower air speed  Higher airspeed iner product Coarser product 16 SEPT-07 HGRS Tikaria_Mill W Mill Workshop Une en airflow distribu istribution  Une en airflow distribution c tion can be identified from (1/2): :  Obser ation of the ducting ucting configuration: - General arrangement t - Relati e position inlet / out t outlet air ducts    Une en wear of paintings or tings steel along the guide ane e anes height Une en wear of paintings or tings steel along the rotor blade blades height Low separator efficiency ency despite low material speci specific loads 17 HGRS Tikaria_Mill W Mill Workshop SEPT-07 How to determine the a e airflow profile  Une en airflow distribution c tion can be identified and e aluated ated from (2/2):    Airspeed mapping at the t inlet of the separator olut r olute Static pressure profile in ile each duct ( ) ineness comparison of th n the fines at each cyclone (ma e (mass balance for each cyclone) lone) 18 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Solutions for e en airfl n airflow profile  E en airflow distribution with n air guide plates  The positioning and length o ngth of the air guide plates should b ould be done considering the air flow ir distribution in the ducting (sta ng (start from where the air is already lready e enly distributed) Too short ort Good Goo Laminar and e en flow across whole duct section 19 HGRS Tikaria_Mill W Mill Workshop SEPT-07 eed distribution < 50 [mm] 20 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Symptoms of une en m e material distribution  Une en wear of paintings or gs steel of the impact ring  Une en pressure loss and fineness of the fines in a cyclone air separator  Separator efficiency is low in spite of low material specific ecific loads  Configuration of airslides fro es from separator discharge to the separator feed point(s) 21 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Solutions e aluation tion  E en as much as possible ible material load to all separator arator feeding points:    Adjust / install splitters rs Install mixing boxes Change airslides configuration 22 HGRS Tikaria_Mill W Mill Workshop SEPT-07 The fineness relationsh mill filter / separator fines tionship MF F If finer than C check: C  Send M to the separator fee tor feed  Cut finer at the static separa eparator (if any)  Reduce mill entilation  Consider a static separator ( cyclone) rator (or 23 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separator operating p ting point (1/2) 100 95 Iso - f neness l ne s 90 Rotor speed [%] of nom nal 85 80 75 70 65 60 55 50 45 40 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 3¶500 [cm2/g] A r [%] of nom nal 24 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separator operating p ting point (2/2) 100 95 90 Bypass 3 Bypass 2 By pass 1 Rotor speed [%] of nom nal 85 80 75 70 65 60 55 50 45 40 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 Bypass 1 > Bypass 2 > Bypass 3 Byp CONCLUSION s to operate the fan at 100% A r [%] of nom nal 25 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Grinding with Ball Mill Syst ill Systems Separators What is separating? g? Splitting a gi en material by pa particle diameter Balls with 2, 4 and 10 mm diam diameter > 3 mm Separation by cutpoint of 3mm (e.g. by sie ing) Problem: Efficiency of separation is ne er perfect < 3 mm 27 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separation efficiency ency  The efficiency of a sepa separation de ice (e.g. mill separator) is a measure of the proportion of unasure separated material follow l following the separation process. It indicates how much fine is in the coarse fraction h fines remaining and how muc coarse is in the fines. much  The efficiency is ery mu dependent on the separator. much Modern cage rotor sepa r separators show a far better efficiency than older sta and dynamic separators. er static 28 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Basic working principle Separators inciples  Particles are accelerated by a ortex or a ed rotating de ice into the direc direction of the separator wall ( z).  The big particles hit the wall (in older e separators) or the guide an (in 3rd e anes gen. Separators) and slip do lip down because they are too hea y for transport by the air transp stream. out by the separator air ( L) stream r supplied by an internal (olde separators) (older or an external fan. The centr centrifugal force is smaller than the impulse o the air ulse of flow.  The small and light particles are carried rticles  Changes of airflow or distribu istributor (rotor) speed (consequence higher centrifugal igher forces) lead to different prod t product fineness. 29 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Main Separators used in Cement works Type Static separators and cyclones es Main features No mo ing parts / fineness adjustment ia mechanical modification Counter blades, distributor plate and internal fan/ ineness control by mechanical adjustment or counter blade speed change eatures as 1st Gen. / but external fans and cyclones Cage rotor instead of counter blades and distributor plate ( ariable speed dri e) / external fan / fineness control by rotor speed change 30 Dynamic separators 1st Generation eration Dynamic separators 2nd Generatio eration Dynamic separators 3rd Generation eration HGRS Tikaria_Mill W Mill Workshop SEPT-07 Static separators and c cyclones Cyclone fines immersion tube Basic function:  Material enters the cyclone in the air stream at the top. feed  A ortex is generated.  A fine ortex with opposite cylindrical part turning direction is generated at the bottom and carries the fine material back to the top.  Coarse material goes to the iew from top conical part walls because of centrifugal forces, slips down and lea es at the bottom.  tailings ine material exits at top ia the immersion tube. 31 SEPT-07 HGRS Tikaria_Mill W Mill Workshop Static separators and c cyclones Cyclones of a cement mill separator 32 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Static separator and cy cyclones fines Grit separato arator immersion tube i ersion t e adjusting ad stin de ice Basic function:  Material enters the housing ho sin cone tailings tailin s cone rad.pos. tailings tailin s feed HGRS Tikaria_Mill W Mill Workshop ¡ ¡   ¦ £ ¡  ¢ adjustable lades ad sta le blades ¥  ¤¤ separator in air stream at the bottom.  A ortex is generated in the ¥ ¥  ¢ top of the grit cone by the blades.  Coarse material goes to the walls because of centrifugal forces, slips down and lea es at the bottom.  ine material exits at the top ia the immersion tube. adjustable by changing the blade position. 33 SEPT-07  Product fineness is Static separator and cy cyclones Grit separato arator Adjusting de ice blades 34 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Static separator and cy cyclones Basic function: KHD V-separator Air + ines Air A  Material enters the separator from the top  Coarse material slips down from plate to plate and lea es at the bottom.  ine material lea es the separator at top together with the air. Plates Returns HGRS Tikaria_Mill W Mill Workshop 35 SEPT-07 Dynamic separators 1st Ge Generation 12 6 Basic function: 5 9 16 10 8 1 7 4 11  Material enters the separator at the top.  Coarse material goes to the 3 15 2 Sturte ant turte  13 14 1 fines chamber 2 tailings cone 3 air ane fineness control al e rod gear reducer main shaft and distributing hub distributing plate walls because of centrifugal forces generated by the distributor plate and counter blades, slips down at the grit cone wall and lea es at the bottom (13). ine material exits at the bottom of the casing (14). adjusted by counter blade position and rods (5) (No counter blade speed adjustment is possible!) 9 fan cone 10 counterblades 11 main fan blades 12 feed spout and intake cone 13 tailings outlet 14 fines outlet 15 air inlet 16 air outlet  Product fineness is HGRS ¨ ¨ § § 4 5 6 7 8 inside drum ¨ § 36 SEPT-07 Tikaria_Mill W Mill Workshop Dynamic separators 1st Generation (Sturte ant) Ge Internal an Counter blades External adjustment of fineness control al e rods 37 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Dynamic separators 1st Generation Ge Polysius Turbopol Air anes Grit cone Distributor plate Counter blades Internal an 38 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Dynamic separators 1st Generation (Example: Pfeiffer Heyd) Gen Basic function: 8  Material enters the separator at 9 the top.  Air stream is generated by internal 10 7 5 4 1 6 3 fan (9).  Coarse material goes to the walls Airflow 2 because of centrifugal forces, generated by the distributor plate and counter blades, slips down at the grit cone wall and lea es at the bottom (11).  11 1 fines chamber 2 tailings cone 3 air ane 4 separation chamber 5 distributor + counterblades 6 distributor plate 12 7 8 9 10 11 fines chamber counter counte blades fan shaft fan blades feed spout tailings outlet ine material is sucked into the outside chamber (1) and exits at the bottom of the casing (12). usually by rotational speed of the plate and counter blades (6+7). 39 SEPT-07  Product fineness is adjustable HGRS  © 12 fines outlet Tikaria_Mill W Mill Workshop Dynamic separators 1st Generation Gen Separator Type Heyd Variable speed dri e for counter blades and distributor plate an Motor an Counter blades eed spout Distributor plate 40 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Dynamic Separators o 2nd Generation tors of separation cham er 2 tailin s cone air anes distri tor plate co nter lades feed spo t ear o motor fines o tlet tailin s o tlet cyclones 2 air d ct to fan fan d st collectin pipe to filter 2 ret rn air d ct Polysi s Cyclopol P 41  HGRS Tikaria_Mill W Mill Workshop SEPT- nd Dynamic Separators of 2n Generation (Wedag) to filter Air flow direction fresh air 42 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Dynamic Separators o 2nd Generation tors of Basic function:  Material enters the separator a the top. rator at  Air stream is generated by the external fan and y is recirculated.  Coarse material is separated b fan suction into ated by the main casing and lea es at the bottom ia a pendulum flap.  ine material exits at the top o the casing by of airflow and enters the cyclone ia gas duct. The clone e cyclones lea es at material separated by the cyclo slides. A part of the the bottom and goes into air sl the recirculated air together with th fine dust from lter. the cyclones goes to a filter. rotational speed of the plate an counter late and blades. 43  Product fineness is adjustable usually by table HGRS Tikaria_Mill W Mill Workshop SEPT-07 Dynamic Separators o 2nd Generation tors of Counter blades Distributor plate 44 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separators of 3rd Gene Generation Basic function: eed Centrifugal orces rifugal  Material enters the separator at the top.  Air stream is generated by external fan.  Material falls down between rotor Air Guide anes Turning cage rotor Air and guide anes. ines are sucked in. Coarse particles are accelerated by rotor and stopped by guide anes, where they slip down and lea e the casing at the bottom.  ine material exits with airflow at the lower/upper part of the casing the rotational speed of rotor. 45 Returns Air with f r fines  Product fineness is adjustable by HGRS Tikaria_Mill W Mill Workshop SEPT-07 Main parts cage rotor s separator Cage rotor Bars Guide anes (in bad shape) 46 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Generation Separators of 3rd Gene 11 Example: P ple: Polysius Sepol 10 5 5 3 1 2 4 9 6 7 8 1 guide anes 2 3 distributor plate 4 rotor shaft 5 feed spouts 6 sealing rotor blades HGRS Tikaria_Mill W Mill Workshop  7 air + fines outlet 8 tailings outlet 9 air inlet 10 gear box 11 motor 47 SEPT-07 Separators of 3rd Gene Generation Dri e Basic function:  Material enters the separator at Prim. air Sec. air Distributor Coarses Coarses Centrifugal force Prim.air Gra ity force HGRS Tikaria_Mill W Mill Workshop      Tert. air Guide anes Rotor    Example: LS O-S S O-Sepa Air outlet + fines eed Sealing the top.  Airstream is generated by external fan.  Material falls down between the ines rotor and guide anes. ines are sucked in. Coarse particles are accelerated by the rotor and stopped by guide anes, where they slip down and lea e the casing with the tailings outlet.  ine material exits with the airflow at the upper part of the casing . the rotational speed of the rotor. 48 SEPT-07 Air force  Product fineness is adjustable by Separators of 3rd Gene Generation Example: O&K cross-flow sepa separator feed s out gear ox otor t r Basi function:  Material enters the separator at the top. distri ut r late utor  Airstream is generated by an air i let inlet uide air guide anes external fan.  Material falls down between the rotor r t r lades se arating zone rotor and guide anes. ines are sucked in. Coarse particles are accelerated by the rotor and stopped by the guide anes, where they slip down and lea e the casing ia the tailings outlet.  fines coarses oarses air + fines outlet utlet ine material exits with the airflow at the lower part of the casing . by the rotational speed of the rotor. 49 SEPT-07 tailings outlet utlet  Product fineness is adjustable s aft HGRS Tikaria_Mill W Mill Workshop Generation ( LS SEPAX) Separators of 3rd Gene 50 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separators of 3rd Gene Generation ( LS SEPAX) Basic function of the compact ve act version:  Material enters the separator at the bottom with the air stream. The air tor stream is generated by an exter external fan.  Material enters the rotor in the a stream ia guide anes. ines are air sucked in. Coarse particles are a s accelerated by the rotor and stopped by guide anes, where they slip do lip down and lea e the casing on the side.  ine material exits with the airflo at the top of the casing . airflow  Product fineness is adjustable b the rotational speed of the rotor. able by Additional functions roller press version:  Roller Press slabs enter desagg esagglomerator under the compact separator where they are crushed  ines go up in the air stream to the separator m fines are separated und go up in the air stream. Rejects go back to the o press  Coarses fall down and pass thro s through the grit separator, where additional 51 SEPT-07 HGRS Tikaria_Mill W Mill Workshop Generation (Polysius Sepol SM) Separators of 3rd Gene Basic function: Rotor dri e  Material enters the separator at es ines with air the bottom with the air stream (e.g. air swept mill)  Air stream is generated by an external fan. Rotor Guide anes uide  Material enters the rotor in the air Inspection doors Returns stream ia guide anes. ines are sucked in. Coarse particles are accelerated by the rotor and stopped by guide anes, where they slip down and lea e the casing at the bottom.  ine material exits with the airflow at the top of the casing . the rotational speed of the rotor. 52 SEPT-07  Product fineness is adjustable by Airflow with material from mill HGRS Tikaria_Mill W Mill Workshop Separators of 3rd Gene Generation (KHD Sepmaster) Sepmaster SKS-D (for RP* circui circuits) feed material feed material Sepmaster SKS-LS (for ASM**) desagglomerator rotor impact ring air and fine product air+fines air+fines coarse fraction 2 coarse fraction 1 feed material+air * Roller Press coarse product ** Air Swept Mill 53 SEPT-07 HGRS Tikaria_Mill W Mill Workshop Separators of 3rd Gene Generation (KHD Sepmaster) Sepmaster SKS ide anes rotor lades 3 3 distri tor plate rotor shaft feed spo t sealin air fines o tlet tailin s o tlet air inlet ear o motor 54  HGRS Tikaria_Mill W Mill Workshop SEPT- Separators of 3rd Gene Generation (KHD Sepmaster) Basic function:  Material enters the separator at the top. tor  Air stream is generated by exter external fan.  Material falls down between the rotor and guide anes. ines are n sucked into the rotor. Coarse pa rse particles are accelerated by the rotor and stopped by guide anes, where they slip down and lea e the casing at here the bottom.  ine material exits the separator with the airflow at the top of the casing arator .  Product fineness is adjustable b the rotational speed of the rotor. able by  Special features SKS-D: Additio dditionally equipped with slab desagglomerator at the top (use in roller press circuits) p  Special features SKS-LS: Used for air swept mills. unction is ery similar to Polysius Sepol SM. M. 55 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Generation (Pfeiffer QDK) Separators of 3rd Gene Basic function: Rotor dri e  Material enters the separator at the top.  Air stream is generated by external fan.  Material falls down between the Air inlet Air + in  ir ines Rotor Returns HGRS rotor and guide anes. ines are sucked in. Coarse particles are accelerated by the rotor and stopped by guide anes, where they slip down and lea e the casing at the bottom. ine material exits with the airflow at the lower part of the casing . the rotational speed of the rotor. 56  Product fineness is adjustable by Tikaria_Mill W Mill Workshop SEPT-07 Separators of 3rd Generati ( ertical roller mill ; Loesche) neration eed Basic function:  Material enters the separator at Separator dri e Sep the bottom with the air stream. external fan. Air Air Cage rotor C  Air stream is generated by  Material enters the rotor in the air Guide anes Gu Returns flow R Conical casing Con Grit Gr cone stream ia guide anes. ines are sucked in. Coarse particles are accelerated by the rotor and stopped by guide anes, where they slip down, lea e the grit cone at the bottom and fall back on to the grinding table. ine material exits with the airflow at the top of the casing . by rotational speed of the rotor.57 SEPT-07  Airflow with material from grinding table HGRS Tikaria_Mill W Mill Workshop  The product fineness is adjustable Separators of 3rd Generation (Vertical roller mill) Gene Reject co ect cone Ca Cage rotor Guide ane system 58 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Separators of 3rd Gene Generation (coal grinding) in VRM Basic function:  Coal from the grinding table enters the separator at the bottom with the air stream. (Used in ertical roller mills)  Air stream is generated by external fan.  Material enters the rotor in the air stream ia guide anes. ines are sucked in. Coarse particles are accelerated by the rotor and stopped by guide anes, where they slip down and lea e the casing at the bottom.  ine material exits with the airflow at the top of the casing . rotational speed of the rotor.  Product fineness is adjustable by the Pfeiffer RTKM Separator for co mills coal HGRS Tikaria_Mill W Mill Workshop 59 SEPT-07 Separator arrangements in grinding circuits ents Single ass design resh-Air Mainly used where ly high cooling is required red roduct eed bins Mill with water injection Separator with filter Mill dedusting filter HGRS Tikaria_Mill W Mill Workshop 60 SE T-07  Separator arrangements in grinding circuits ents Standard Arrangement 1st Genera eneration Separator 4a 1 3 4 5 Product 2 1 2 3 4 4a eed bins Mill with water injection Separator with filter Mill dedusting filter Grit separator Optional cement cooler Tikaria_Mill W Mill Workshop 61 SEPT-07 5 HGRS Separator arrangements in grinding circuits ents Cyclone Air Separator 1 3 Product 4 2 1 2 3 4 HGRS eed bins Mill with water injection n Separator with cyclone and d dedusting filter Mill dedusting filter Tikaria_Mill W Mill Workshop 62 SEPT-07 Potential Problems  Wear /  Clogging  Wear  Sealing not tight  Wear  Wear  Blades too short 63 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Potential Problems  Wear,clogging  uneven feed distribution  Wear  Wear 64 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Potential Problems  Wear  Sealing not tight  Wear  Guide vanes not correctly adjusted  Wear  Breakouts HGRS Tikaria_Mill W Mill Workshop 65 SEPT-07 Potential Problems / cl s clogging Cage rotor separator casin r casing partly clogged guide ane system Material deposits due to insufficient airflow or airflow distribution 66 HGRS Tikaria_Mill W Mill Workshop SEPT-07 Reduced separation efficiency 1st and 2nd generation dynamic separators ncy Gap between internal fan and separating chamber bigger than 5 [mm] Reduced number of counter blades Gap between counter blades and wall of separating chamber bigger than 10 [mm] Possible consequence: Desired P fineness can not be achie ed anymore fi 67 HGRS Tikaria_Mill W Mill Workshop SEPT-07