Document 2JD72RqX4OVjKXXKxpVV3j5JR

E, I. DU PONT DE NEMOURS & COMPANY PIGMENTS DEPARTMENT NEWPORT PLANT PIGMENT COLORS RESEARCH REPORT SUBJECT: LONG RANGE MODERNIZATION PROGRAM ALTERNATE EQUIPMENT STUDIES - SIZE REDUCTION "WITH VIBRATING BALL MILL PERIOD COVERED: MARCH, 1966 - JANUARY, 1967 DISTRIBUTION: c o py m / ^ 1 - Research Numerical File 2 - Research Office File 3 - M. Hunt/E. Conick 4 ** W S. Struve/A* A, Brizzolara 5 - J. EL Cooper/B.H. Pei-kins/H,R,, linton/B\F Ehrich 6 - W, J. McClure/R, A. Hageman/FL Amoul/Q.C. File 7 - P* J. Monahan (Vital Records) 8 - E. I*. Rodowskas/N, A* Jenkins 9 ~ 0. M Loughraa/P N* 0dell/Q*C4 File 10 - R, H. Wetzel 11 - J W, Minnich 12 - Ho H# Gyorgy 13 - J. P. Maurer 14 - R. E,, Stuber - Louviers 15 ~ N. R. levins - Louviers 16 - Go E, Rick 17 - Research File - Colors - Newport IS ~ Extra 19 ~ Extra 20 - Extra 21 - Extra 22 - Extra 23 - Extra 24 - Extra 25 - Extra NEWPORT PLANT PIGMENT CODORS RESEARCH REPORT SUBJECT: LONG RANGE MODERNIZATION PROGRAM ALTERNATE EQUIPMENT STUDIES - SIZE REDUCTION WITH VIBRATING BALL MILL PERIOD COVERED* MARCH* 1966 - JANUARY* 1967 SUBMITTED BY: D.. H* EASTE&M APPROVED BY: J, W. MJEEZOm^i Date Submitted: 1/9/67 Date Released: 3/1/67 DUP050027045 ~1~ I IKTRCDtrCTIOK As part of a program to modernise the CPC operation-, reduce costs and improve productivity,, an improved method for size reducing CPC was desired. This study was con ducted to provide information for future planning and expansion of CPC facilities. Activity centered on a vibrating hall mill as a prime candidate for the follow ing reasons; A. Rasy to charge and discharge. B. Smaller and less expensive than rotating mills, C. Easily adapted to pressure relief system. More work is recommended on premilling and solvent milling to optimise the operation. Attention should be directed toward optimum charge of media and pigment* respectively. n, conclusions A, A vibrating ball mill will provide a practical* effective means of producing premilled CPC at an economical production rate, B. A vibrating ball mill does an excellent job of sol vent milling.; one vibrating mill has capacity of two existing rotating mills. C A vibrating solvent mill can be practically equipped with a safety relief system, D, Dispersion milling capacity of a vibrating ball mill is not great enough with commercially available mills to justify replacement of existing mills or use for additional expansion, E, Temperature control would be a difficult problem with a commercial vibrating dispersion mill, XIX. SUMMARY A vibrating ball mill is essentially the same as a conventional ball mill except the grinding energy is supplied to the grinding media via vibration instead of rotation. At the vibration frequency and amplitude nor mally used, the rate of energy input per unit volume grinding media is to the order of 10 times as great as a rotating mill which results in a much higher grinding rate. Effectiveness of a YBM (vibrating ball mill) was determined for use in existing milling operations for equipment replacement or as a means to expansion. DUP050027046 ~2- III, SUMMARY (Cont'd) Premilling A commercial scale mill (30 gal,} has- demonstrated, a high rate of strength development as evaluated by solvent breaching. A Schut2-0sNeill, Model 250 L (210 gal.) operating tinder similar conditions is capable of producing premilled crude at an instantaneous rate equal to existing plant premills. Where longer pre milling cycles are required for solvent breached pro ducts , the vibrating mill offers even more advantage. Production rates were compared on an instantaneous basis assuming existing premill loading is 1,200 lb. with 6 hr. grinding time. Excellent operability has been experienced in both lab and commercial scale mills. Solvent Milling The Schuta sOsHeiil mill was also effective as a solvent mill (acetone milling) but most favorable candidate is a "Sweco Yibro-Energy Wet Grinding Mill". The ,,Sweco% Model M8Q (182 lb. GPC/hatch) mill offers larger batch size than Schuis-O'leill mill with instan taneous grinding rate equivalent to two conventional solvent mills. With the relatively stationary machine, a pressure relief system could easily be provided. ..Dispersion Milling Dispersion or "salt" milling proved to be the most difficult, A combination of milling variables was found that produced a satisfactory product but the instantaneous grinding rate was not sufficiently high to justify a commercial installation. The same problems that exist with conventional rotating mills are also present with the vibrating mill. Prom a heat transfer standpoint, a vibrating mill would be more difficult to operate because of the higher rate of energy input per unit surface of heat transfer making temperature control more difficult. IV. DISCUSSION General The most comprehensive theory available on vib rating mills is developed in the publications Vibration Mills and Vibration Milling by H. E. Rose anSHTTHlT lT^u3.1iv8n^CcnWab'le-"f^aon).. The following equation was developed by the .authors to predict the power input to the charge: DUPO 50027047 "3" XV. DISCUSSIQi' (Cost1 d) (Coat'd) Where: Pc * Pc CO *" cP " Me * 3.0 x XV'&cJ 3^2 Me Power dissipated in charge of BM, M Frequency of rotation, radian/sec. Amplitude of vibration, cm Mass of charge, kg. During tests at vendor's lab, mill temperatures were measured before start-up and during milling. Neglecting the effects of conduction and radiation, the equation above was found to agree within reason with the temperature measurements. The temperature rise per unit time and total mss was known which was assumed to be the energy input to the charge? this energy was 50$ below that predicted by the equation which is a reasonable agreement considering the assumption that ignored all heat losses. Seale-up of VBM lab data does not appear to be a problem. Tests conducted in a commercial scale mill agreed with lab data. This is not surprising when the mechanism is examined-? a small mill is Just a section of a large mill. Premilling A Schutz-05 Weill, Model 250L, VBM mill produces premilled crude at mi instantaneous rate equal to existing premills. Caking tendency, an anticipated problem with a vibrating mill, is not serious when using grinding media composed 80$ cylpebs and 20$ 1/2" steel balls. A lab scale VBM, acquired for development pur poses, can be utilized to more rigorouly optimize presuming. Figure 1 exhibits the rate of strength development in lab and large scale tests. Figure 2 shows the approximate relationship of 2 of the con trolling variables in VBM size reduction (because of scant data, a linear relationship was assumed). From Figure 2, the amplitude of vibration has the greatest effect on rate of strength development. The loading (100$ loading assumes filling voids with crude pigment) has an effect but not as pronounced. Capacity calculation was made on following basis: Grinding Media Crude CPC Zh~ 80$ 150$ (Baaed on void volume of grinding media) DUP050027048 .. Au- I?. D1SGWSSX0H {cent5d) Premiliing (Coated) Physically* a loading of 160# is maximum that can be physically added with a media change of 80#. According to Figure 2, at the end of One hour a loss of 2 points of strength would result from 150# load ing but strength is still equal to standard. Obvious ly* the premilling operation was not optimized and the opportunity is available to probably exceed the capacity of existing mills. All comparisons were made to N-930 standard which now requires 15 hour premilling. The same grinding times are assumed to apply to premilled crude for solvent milling but it is possible that shorter mill ings may be satisfactory for use in solvent mills. A commercial premill would produce more but smaller batches probably necessitating the use of automated bulb handling equipment to keep labor costs to a minimum. Allis-Chalmers manufactures a TOM with 90 gal, grinding chamber powered by two 75 HP motors (Sehutz04Neill has one 30 HP motor) which provide an extremely high rate of energy input, The largest A-C mill sells for about $22 ,>000 compared to the cost of a Schutz0*Neill mill of $11*000, A-0 is working on larger vibrating mills but short bearing life has prevented full-scale marketing. Another contact should be made at a later date to determine A~C8s progress in this area. Solvent Milling The solvent milling (acetone milling) responds very favorably to vibratory milling. Two types of mills were tested* the Sehutz-08Weill mill and a "Sweco Vibro-Energy Net Grinding Mill". The Sweco (Southwestern Engineering Co.) mill was the most attractive from capacity standpoint because of its relatively large size (182 gallons batch size), A smaller Sweco mill was tested at the Experimental Station and strength development rates indicated that one Model M80 Sx^eco mill has the capacity of 2 existing solvent mills. Rate of strength develop ment is shown in Figure 3. Capacity calculations are included in Appendix. If additional dispersion milling capacity is required at Newport in the future* one TOM solvent mill could be installed to replace 2 existing solvent mills and free one mill location for installation of a dispersion mill. DUP050027049 5- IV. DISCUSSION IGoat d) Solvent Milling; (Contra) A "Sweeo" Model M80-sells for about $24,300 and could replace two solvent mills with replacement (equipment cost) value of about $30,000 each. One obvious advantage over existing rotating mill, would be the ease of providing a pressure relief system because of the stationary nature of the mill. Mechanical considerations preclude the use of a relief system with our existing solvent mills. The solvent milling operation was not optimized and the opportunity to achieve even greater production from a given mill is open. For example, during testing it was noted that circulation of slurry through the grinding media was excellent which could make possible smaller grinding media charges and more CPC-solvent slurry,. Dispersion Milling Dispersion milling responds favorably to vibra tory milling- but not to the extent of premilling and solvent milling. In general, premilling and solvent milling is about 600$ faster than rotating mills dispersion milling is about 250# faster - not enough to Justify a plant installation. The principle that makes vibratory milling more rapid, high rate of energy input, would make disper sion milling oh commercial scale difficult. The ratio of energy input to heat transfer area in a VBM is much higher than existing rotating mills which would create a temperature control problem. Tempera ture control in existing dispersion mills is near marginal. Above 75~80oC experience has shown that caking of the charge is almost certain. Maintaining a plant scale VPM below 8oC would be extremely diffi cult plus the incentive is not great enough to develop a suitable technique. Satisfactory products were made with half the standard amount of alum$ this would increase milling capacity but still not enough. To be attractive, the milling time, would have to be to the order of 1 hour. Equal strength (to standard N-797).was achieved in a minimum of 2-1/2 hours. DUP0 50027050 Discussion (Cont'd) Dispersion Milling (Cont'd) Various grinding media were tried until an acceptable combination was found to be a mixture of cylpebs and steel balls (same mixture as for premilling). Balls were included because of higher grinding rates than cylinders. The sharp edges of the cylpebs (1/2" x 1" steel cylinders} seem to keep the mill walls clean and prevent caking. The test results are shown in Figure 4 with the effects of alum concentration and amplitude of vibration shown in Figure 5 The curves in Figure 5 are only approximations and would require addi tional. testing for precision. However;, the role of both amplitude of vibration and alum concentra tion is apparent. At practical levels of amplitude the effect of reducing the alum/CFC ratio from 6 to 3 added about 1-hour of additional grinding. This doubles the amount of CPC present and increases grinding capacity about 1* The most notable result was achievement of a BCD (N-797) product that was 5-7$ stronger than a lab extracted in-process standard. REFERENCES Research Notebook No. 5098 .. Correspondence! R,E Stuber to D.H,, Eastham, 3/17/66$ CPG Size Reduction Via Vibrating Ball Mill R.Eo Stuber to D. H, Eastham, 6/24/66; Acetone Milled CPC Analyses R.E, Stuber to D.H. Eastham, 7/6/66; Vibrating Ball Mill Tests on CPC Pigments Literature: Allis-Chalmers literature, operating instructions Allis-Chalmers Manufacturing Co. Milwaukee 1, Wisconsin Schutz-O'Neill literature Schutz-0'Neill Co. 307 Portland Ave, South Minneapolis, Minnesota 55415 Sweco - Vibro-Energy Wet Grinding Mill Southwestern Engineering Co. 6111 East Bandini Blvd. Los Angeles, California 90054 DUP050027051 APPENDIX DUP050027052 PBBMXLLIHG TESTS EXPERIMENTAL DATA i j 4HV oH t l 00 si- PP P 59 13 > j sI l t j Ci fct S3 OJ 04 MP ra ri--n1 OH t PS PS t C\ uo mra tn t> i t1 1I I CO Qr-4 <O0 H -AHO rH co o H O H 0o4 #*4 o o Cfi in n 0 4 o j H r) <H H r-i t-} r-f *afl v4 0H0--0H00OH HoO OO or-i Ho oHO oinocmooion v<coonvfcooo vo o omoioco o icoo <0 vH'-C0pii t! tA tv &H . * isnv* - . ^ oino* tino OJ OJ CP00dOvPsS5g Vo<HOSi~x. o *> pS- *H3 S*n r! 0 SB ions h in oj oin oo in in 04 oin oo in cu oin oo Oini Oin OO in 04 Oin d d H d d H ddHo d Hf . v fHt OS rl - in tv 04- p t=--4*3 pCS O CO O P'xi- VO DUP050027053 -8 Newport, Delaware February 3? 1967 LONG BANGS MODERNIZATION CAPACITY OF YBM - PREMILLING Commercial scale 3chutz~05Neill mill Model 30L, demonstrated essentially equal strength after 0.75 hr. grinding time at 85$ loading. Assume this rate applies in Model 25OL at 150$ loading, 2501 - 29.5 Ft.*'- Total Volume Grinding media will Occupy 80$ of total volumes Porosity of charge is 45$; use 150$ flllage of voids, sos <29.5 Ft..*) (0,80) (0.45) (1.5) - 15.9 Crude CPC * 10 lb./ft,, (15-9) (10) = 159 lb, CPC Grinding time - 0*75 Hr, 212 lb./hr. Instantaneous Sate for VBM Existing Mills Charge 1200 lb. Grinding time - 6 Hr. 1200 KMHUWIHBW 6 200 lb./hr. for Existing Mil Do H. Eastham 12/30/66 DUP050027054 t o X t o TO T H E Vjs iN C H 3 5 ? - 1 T rJ S K E U F F E L & E 6 S E R C O . JiAO tlK tt.S.A DUP050027055 m. i.U.~_U i feUu r* ',--..^.g ^f;,,?...:.:r_..:...t...... .t.,r... K..r.h. - .:.Kp * l- - rtSWA'-. v- ! &.sstr*.t}r i <i 5. k !1^'..*. r, ^ *; 7' Is:. .!'.: * ?4;!,.' .; ;^us.4,,...s.:j. ;.^. ps.....^....,.^ .^j UN *: ; . i 4 \ '.; rr:T:; 1 ' u; 7-"|i>r' a m t s u .s .a . 10X10TOTtf 'Ev* IWCM 3SS4 5 K e u rfe L ^i cssst&c. . ir' U: ' > l/j -'--l' :yri j{;; !;' ; 1i_____ Li ._L_L1 u: ? ' ! -4~-: Mill Charge Newport, Delaware February 3, 1967 LONG RANGE MODERNIZATION ESTIMATE OF POWER INPUT 4000 g 5300 g Total' weight (Grinding Media Mill) . 66 g Charge 5300 and Mill, etc, 1620 RPM 3*5 mm Displacement 57.3 */Bad. i||2. * 27 EPS 27(3601 169.5 Had./sec. Pc * 3 x 10~8 co3 d. 2 Me oC == 1.75 am Amp. 0.175 cm Pc = 3 3t 10-8 (169.5)3 (0.175)2 (5.366) Temperature Else 6F In 10 Min. 7F in 10 Min. Avg. cPSteel 0,12 Btu/lb.F 6,5F in 10 Min. 0,65/Min. Q Mcp A T m - 5366 11.82 lb. 454 (.11.82) (0.12) (0.65). Q, * 0,923 Btu/Min. 1 EH Hr. 3412.19 Btu KWH (O.923) (60) 55*4 Btu/Hr, 55.4 Btu/Hr. 3TX2Trrtr^OTFr 0.016 EW 0.0243 1.5 -{ 50$ D. H,, Eastham 12/29/66 DUP050027057 co 03 sy H H n I 8 CQ as 03 4? g;d. rail O II'1 5 fO.1 <3 ^ WJ oP Sj 15^1aff^etg>l5l3!v<gjaspws & O &OM SH 13 !:~,i SO *H ,C>5 td *ri 4i S3 w> r5.p*r3 63 G*H to t) *3 H *rt H a to -P 0 o S-SoSSS S3 O fc J I in H a >> 8 & m> m> & >w 0a*3* & a X! X &1 g p H H i-H H CO fi o5 5 If ds!4 -- PaS 8-8X8 8 HH HH 3 Hri Cf *Sritro-5 > $ S3 P c m* <\*i vo. O o CM CM CM ia tn ifi fi-- c-- t-- -ri. CM* CMm CM0 O OO I I CM CM CM & .8Is P.PS t-- t-- CM CQ H H H in in in -* & & e H HH fl < H in w g i-i < Ol CQ sJ" to W 4-10 W (O M3 o h Sill. VO S3 y> o>R C<3e31|l- N^^>r- tr~ *inS a *1 o in < in <n m\ DUP050027058 -13- Ifewp.ort, Delaware February 3> 1$67 LONG EAHGE MGPERHIZATiaH SOLVEHT MILLING ~ VBM - CAPACITY Assume use of Model M8o - Slurry volume 182 gal; (182 lb. dry CFG)* Tests at Experimental Station were not conducted at maximum amplitude / higher rate of strength development can he expected. At demonstrated grinding time of 4 EH. capacity on Instantaneous basis would he; Existing Plant Bate; s* .1.65 x Existing Solvent Mill 27.6 20 HR. * 27.6 Lb./HE. For 3 HR. Grinding Time; 1.82_Lb... G_M ,, 6o 3 HR. Lb. CPC HR. To Equal 2 Plant mills need; 182 * 3.32 Hr. Grind Time "rrro Strength deficiency was less than 1% at 3*32 Hr. from Figure 3. X am assuming that using maximum amplitude will more than compensate for the strength deficiency. DUP050027059 1 0 X 1 0 'TO T tfS 1-a IN C H KEUihTCL 6 CO. DUP050027060 DUP050027061 KK>eXurt'OmTsOtsTsHmE cAo* .I'N C H a 10X10TOTHEVaINCH 3SS-! 1 KEUFFEL & ESSER CO. * is *.*. DUP050027062 m t- o WnP) U^Q> n-AtAo<<:xs9> sAEa>** r*HH rSj o *tr>it O wS634 *H aot ,rs6-> p:; Pa> jb <ej c3 HH Ggi- <u c *0> ;>> rH *c* *<1u p* g o 8 *ad1> 2Sc d a) to *a*5> ^4 H. ao P 48> 0) *C& *grt Ist *p*i a -atroi 8A a-s r-di oC -rTSHPHJ3 & -<0mHL2> t nbPHD S S5 Xo3OUl -H .CaOO H> C r<do O -S0PH4 -P rrHH O q oa -ioS3> rnsH (U o -VoP> *rl 01 o P 'nCHJ <u ao o s o DISPERSION MILLING TESTS o <oC3O <cf3ot <cr=r>mt hr--t rmtCM I >> o HCO f>C3t--OI Cl--MI HCrHJ J0>r3t CO CO II O O .stop W r) Cp O O VS CD UTN WCJ I rvto CD O O>ea COHO CO9O) CrI3TlS rt -s 8 8s bSP3^ *4 o oo fo--3 orH* ro-H o ro*t r8t 0 ort O Ho o trun <5 CO iI--P1s rt =* CrJt Ort rH rH O s m orrt o oo o o rot o--I o--I oc--) oi--I o o 1 rH 0orH 0roH o0rH oorH oorH oroH vrOHoOrvHoHO^oOoN orrHH OHco oOrH cn .= SI O rt cm <O--3 C?> r co ro vo tn Os--I OsCTsrOt 0\0s bo jb r-H 0) Si-I 3^I*i iCopMoOCOtOs--o CO_M* OtoO_ IOPS O_ O_ I,P_s IPs IPs CO bQ 'r(3t S 6H JOmt- o ^ poH IPs o o o_ o o o o o O O UPsO O IPS O c+vi VO VO VO CVJ CO -=J- r-H CM co c m roin c m co l ps co *CPCQ5*P^A5 VOO rHH g**s -I s tr\ co CM ^mpj n> o vo v5o0 joo vo CirMv ClTM% VO vvpo o CO ir\ LTN CIfMN iO(rP*t CrIsPMt\s OCM- OCM* O CM O CSJ CIPMS CVJ eIP--s CM tIP-s CM tIP^sCIMPs CM CM H ro H vvoo vVOo CM rH oro .<oo CO rH co rH rH coco H ro \rcHo VrrHo v\Ho v\oo in vt--o CM of-4 OH CM CM CM vo^ H DUP050027063