Document x1jpx6kXqMbZQVodY2JRVD07b

E. I. DU PONT DE NEMOURS & COMPANY PIGMENTS DEPARTMENT 256 VANDERPOOL STREET NEWARK, NEW JERSEY Copy No. 1 JL-li-'i ^ \ \ NEWARK PLANT PIGMENT COLOR RESEARCH REPORT CENTRIFUGING STUDY* ORGANIC COLORS Period Covered: March 4, 46 X0 4 % FILE: DATE: 8/1/46 X N39994 8*?lal So* iU'i-4u"-4o Copy Hoo 1 Copy toi X - Kcraorlool Fil 2 Escearoh Office (L142) 3 - Library File (114,2) 4 #10 Building File $ -# 6 * 6 Imperial Cheadoal Industries, Ltd* y,, n <i b h Q 9 W, F* Speageman, Hewarfc 10 - Extra HESHBIK mg FI0SS5MT COLOR U^MRGH KEPOFffl Prop1 ess Report TitloJ CEHTRIFUOTEG HUBYs ORGfiSIC COLORS. Period Cereredt Sfcrc'i 4S 1946 <> Jit'Ll, SBBKL'frrBs *fuly 3.3, 1946 DFiTE ISSBCTl 8/1/46 N39994.01 DUP050150424 With the initial ebjeot to make use of idle time in the projected Bensidino Yellow 40** basket centrifuge, and eventually to substitute centrifuges for wash presses wherever justified, development work.has keen initiated in the seed"-work s on the cmtrifugaetion of .orgaaie color? t The plant has supplied a list of sixteen pigments to bo tested, and experimental work, of a high spot nature, is being carried out on the Setsl-'Werks Bird 12" perforated basket eontrlfugo, wmujmswm Of the 13 oolots tested to date, based on the assumptions listed below, th follossiag 9 appear to be likely candidates for centrifuglngi RI>211"D, HB-6-B( HT-435-S, RT-499-P, RT-533-B, 8T~l8l~, BP-173- and SF~28 Those -^Mcli say offer difficulty are 3T'4*JH>* RT~42843, RS-436-D and F.T-34?-. In preparing the following tabulation, the following assumptions have been cadet la & eeai"p factor of 25 froia the 12" to th 40" machine, 2 b labor reqjiiroBcnt 9 14 klofi pcs- ooairifug eharg and pressing roosa labor costs of. 033*70/1000 ^iffiSa 2 O? Costs for centrifuge * direct Ichor plus electrical 4* OF Coots for filter prsea * direct labor plus stmts* ,5 Bleed losses equal for both (certrifuge actually operated without bleed losses}* 4 6* da arbitrary steca eeueumption of 0*?5Xfes cfcecsa to punp a gallon of slurry through the press S& ai.-2.ll-3 b k -SS-s KT-43jH> &T4?5*I5 ET-533-B ST-lSi-C BT-X72~ K?*28 7* Production figures, at best, represent .the vcr.g of not sor than two runs* *i' *& $s ^ <*! <&.''w.i'MWa 1X43 io o x 6 $3 319 ;4i- 33 X?6?- in .U..C Centrifuge Production* U5 2?3 131 51 42 ^sn** 48 sal 22 Demote?, wash. Discharge Time, * wm**** 10,0 34 5.0 6*2 13*1 44 T.9 5*0 5.0 Present Av Flltdr, Wash as$a*.. $jSjsj& S^jKlSiSf- ZM&flC 20 brs. vat seek 8 hrs. 13*15 13*37 6 4,33 7*12 8 5,13 13,96 13*5 7,20 9,00 3.5 10*43 12.55 6 c4" 3*55 T.JO 11,04 13.80 12 9*50 15.05 8"10 5*66 no data . BS-425-B RT-423-3 2S"436"3| RT-34?0 480 836 ns 40? 3* 39 39 24 14,0 22,3 19,1 15,8 n 11*71 17.96 13 17*06 13.85 5*5 14,43 17.05 11 10*50 12.89 DUP050150425 2 * {similar data will b compiled for the rc-saining three eedoa, RT366"-Dg RT-42 ?=>, and G*65Q"B# as they ars scheduled for production in the plant. pisQPasioa Qv mBWsz To make on cocurats datssmsination of the production to ho expected on the 40* machine , ecslc-up factors should bo calculated for e&oh of the sixteen colors for which such information is desired. This would involve asking at least three runs at & minimum of three centrifuge cake thiohnesses for each pigment, measuring rates of filtration, calculating ssrc&s, driving force and viscosity, then solving the Lewis equation for optimum produstion rates. Such an undertaking is beyond the scope of the present problem* For simplification, therefore, a scaling factor of 25 has "obo selected for all of the pigments tested. This is felt to be a very conservative figure, easily attained in the light of the experimentally determined factor of 50 arrived at for Beasidine fellow. One observation should be noted at tk point. Is general It has been found that dilute slurries filter and mash lees rapidly than concentrated slurries. This may probably be explained by the presence of a liquid layer building up behind the layer of solids and exerting a pressure forcing a decrease in else of the interstices between the solid particles and slowing dean the rate of filtration. This effect becomes more serious the more compressible the cake. Based on the information attained to date, no conclusions can be dram eg regards effect cf slurry tcapapasture on rat of centrifugation. It appears to vary from pigment to pigsent. It should be noted that all runs mere made at a constant basket speed (3500 SKIS), that the basket v&s loaded at full epoed, snS that the tearket m run as full of slurry as possible at all times. The costa reported arc very ouporfioial ia nature smd are not presented t this time to attempt to justify subotitirfciea of centrifuges for mesh presses. At best, they reveal centrifuge costs in line with (and probably lose than) filter press costs. ESFBRIkEKTAL DETAILS A sample calculation shows how figures in She table wore obtrinodi *MH^~83c33lk2. Batch si* " 1143 lbu Present Cycle ~ 20 hr. vat wash plus 8 hra. to filter and discharge. *A DUP050150426 "3*' la Calculation of Centrifuge cyoles Gallons filter*! 8} Solids in slurry 0*24 Ibe./gal. cake/etrfge ekarg 8 s 0.24 1.92 Tim to filter 6 minute* " wash * 12 (Cl free) " * oriag; *3 Start, stop, discharge 4 Total 25 Seale ap faster 2$ (assumed) Production for 40" machine Is^JLJ^JSJgS o U Ibs./V* 25 Begat or, 'ffi&sh, Bisoliarge Time * 1M3 , iq j^g, 2 Calculation of costs for centrifuges Labors 1143 lbf./featdfe * U J&gfU * 33.70 8/1000 hima $ll.i5/ (1%?2 x 25) lbs,,/ehsrg* charge bat oh Electrical (assume 20 IIP, $0.0127/ hr} 10 hrs. X 20 HP s 0c?45 SSf/SOP x 0,127 $/ter - $lo90/bat*h Total $13ol5/batoh 3c Calculation of Costs for filter press Labor* (Color Press Op $832/Wfcefcf pumper * $400/bstoh) 8c 32 * 4.00 8l2.32/batsb Steam* (0.75 # staasa/ gal. slurry, 0.70 9/lDOOjf steam) approx. 2000 gals, slurry (after waters drawn) 2000 gala, x 0.75 * f1ia00l0L l.O.<S*/.b atoh Total 8l3o37/t0h Details ttx-y b found la BBSS 46=18 J, DUP050150427