Permissible flow rate

This factor enters into consideration of semibatch and steady-state operations, where it leads to the determination of the cross-sectional area of the equipment. Considerations of fluid dynamics establish the permissible flow rate, and material balances determine the absolute quantity of each of the streams required. 

Figure 5.8 The overall flow rate of key components is constant for any sequence of simple columns. The overall flow rate of nonkey components varies. (From Smith and Linnhoff, Trans. IChemE, ChERD, 66 195, 1988 reproduced by permission of the Institution of Chemical Engineers.)...

Nature of aqueous feed Organic-aqueous ratio required Permissible settler flow rate, U.S. gal/(min-fd) borizontal area... 

FIG. 26-49 Effect of water vapor coodeosatioo 00 voliioie flow rate of air ioto taok. Fullaiton, Evtipidis, and Schliinder, 1987, hy permission of Elsevier Science S.A., Lausanne, Switzerland.)... 

FIGURE 2.12 Pressure drop as a function of liquid fiow through a packed bed of Superose 6 prep grade packed in a HR 10/30 column. At high velocities of the mobile phase the beads are compressed and the void channels reduced, which leads to a high pressure drop. If this happens, the material can be resuspended and packed at a lower flow rate. [Reproduced from Hagel and Andersson (1984), with permission.]... 

FIGURE 8.13 SEC of casein hydrolyzates. Numbers above the peaks refer to the number of amino acid residues in the typical peptide in the indicated fraction. Column PolyHEA, 200 X 9.4 mm 5 /zm, 200 A. Flow rate 0.5 ml/min. Mobile phase 50 mtA Formic acid. Detection A250. Samples (A) Pancreatin hydrolyzate and (B) tryptic hydrolyzate. (Adapted from Ref. 29 with permission from Silvestre et of. Copyright 1994, American Chemical Society.)... 

FIGURE 10.5 Protein analysis on SynChropak GPC 100. Column 300 X 7.8 mm i.d. Mobile phase 0.1 /H potassium phosphate, pH 7. Flow rate I ml/min. (From MICRA Scientific, Inc., with permission.)... 

FIGURE 10.14 Analysis of polyvinylpyridines on SynChropak CATSEC 100,300, and 1000 columns in series (250 X 4.6 mm i.d.). Flow rate 0.37 ml/min. Mobile phase 0.1 % trifluoroacetic acid in 0.2 N sodium nitrate. Detection by differential viscometry. (Reprinted from Ref. 9 with permission.)... 

FIGURE 22.8 Flow rate effect on the elution of polyacrylamide. Degradation of polymer during the analysis occurs in each case at flow rates just above those shown. Unmodified MW = 12-15 x I0 carboxyl substitution = 9.5%. , unmodified A, sheared for 30.0 min , sheared for 12 hr O, sonicated for 1.0 min O, sonicated for 5.0 min. (From Ref 23, Copyright 1988. Reprinted by permission of John Wiley Sons, Inc.)... 

Figure 12.10 Microcolumn SEC-LC analysis of an acrylonitrile-butadiene-styrene (ABS) teipolymer sample (a) SEC ti ace (b) EC ti ace. SEC conditions fused-silica column (30 cm X 250 mm i.d.) packed with PL-GEL (50 A pore size, 5 mm particle diameter) eluent, THE at a flow rate of 2.0 mL/min injection size, 200 nL UV detection at 254 nm x represents the polymer additive fraction (6 p-L) tr ansferred to EC system. EC conditions NovaPak CIS Column (15 cm X 4.6 mm i.d.) eluent, acetonitrile-water (60 40) to (95 5) in 15 min gradient flow rate of 1.5 mL/min detection at 214 nm. Peaks identification is follows 1, styrene-acrylonitrile 2, styrene 3, benzylbutyl phthalate 4, nonylphenol isomers 5, Vanox 2246 6, Topanol 7, unknown 8, Tinuvin 328 9, Irganox 1076 10, unknown. Reprinted with permission from Ref. (14).

Figure 12.11 Coupled SEC-RPLC separation of compound Chemigum mbber stock (a) SEC ti ace (b) RPLC trace of fraction 1, dibutylphthalate (c) RPLC trace of fraction 2, elemental sulfur. Coupled SEC conditions MicroPak TSK 3000H (50 cm) X 2000H (50 cm) X 1000 H (80 cm) columns (8 mm i.d.) eluent, THE at a flow rate of 1 mL/min UV detection at 215 nm (1.0 a.u.f.s.) injection volume, 200 p-L. RPLC conditions MicroPak MCH (25 cm X 2.2 mm i.d.) column flow rate, 0.5 mL/min injection volume, lOpL gradient, acetonitrile-water (20 80 v/v) to 100% acetonitrile at 3% acetonitrile/min UV detection at 254 nm (0.05 a.u.f.s.). Reprinted from Journal of Chromatography, 149, E. L. Jolmson et al., Coupled column cliromatography employing exclusion and a reversed phase. A potential general approach to sequential analysis , pp. 571-585, copyright 1978, with permission from Elsevier Science.

Figure 12.18 LC-SFC analysis of mono- and di-laurates of poly (ethylene glycol) ( = 10) in a surfactant sample (a) normal phase HPLC trace (b) chromatogram obtained without prior fractionation (c) chromatogram of fraction 1 (FI) (d) chromatogram of fraction 2 (F2). LC conditions column (20 cm X 0.25 cm i.d.) packed with Shimpak diol mobile phase, w-hexane/methylene chloride/ethanol (75/25/1) flow rate, 4 p.L/min UV detection at 220 nm. SFC conditions fused-silica capillary column (15 m X 0.1 mm i.d.) with OV-17 (0.25 p.m film thickness) Pressure-programmed at a rate of 10 atm/min from 80 atm to 150 atm, and then at arate of 5 atm/min FID detection. Reprinted with permission from Ref. (23).

Figure 13.9 Coupled-column RPLC-UV (215 nm) analysis of 100 p.1 of an extract of a spiked soil sample (fenpropimoiph, 0.052 mg Kg ). LC conditions C-1, 5 p.m Hypersil SAS (60 m X 4.6 mm i.d.) C-2, 5 p.m Hypersil ODS (150 m X 4.6 mm i.d.) M-1, acetonitrile-0.5 % ammonia in water (50 50, v/v) M-2, acetonitrile-0.5 % ammonia in water (90 10, v/v) flow-rate, 1 ml min clean-up volume, 5.9 ml transfer volume, 0.45 ml. The dashed line represents the cliromatogram obtained when using the two columns connected in series without column switcliing. Reprinted from Journal of Chromatography A, 703, E. A. Hogendoom and R van Zoonen, Coupled-column reversed-phase liquid cliromatography in envir onmental analysis , pp. 149-166, copyright 1995, with permission from Elsevier Science.

Figure 4-64. Variable orifice MultiVenturi Flexitray scrubber at essentially constant pressure drop maintains good efficiency over wide flow rates. By permission, Koch Engineering Co., Inc.

Figure 8-133. Weeping performance comparison. (Valve tray also gives a lower weep rate at a liquid flow rate of 50 gal/min/ft of weir.) Used by permission. The American Institute of Chemical Engineers Hsieh, C-Li. and McNulty, K. J., Chem. Eng. Prog. V. 89, No. 7 (1993), p. 71, all rights reserved.

Figure 9-79D. COg absorption from atmosphere effect of flow rates on Koa at elevated pressure. Reproduced by permission of the American Institute of Chemical Engineers, Spector, N. A., and Dodge, B. F., Trans. A.I.Ch.E., V. 42 (1946) p. 827 all rights resenred.

Figure 10-44. Keep track of fouling by monitoring the overall heat transfer coefficient as a function of flow rate. (Used by permission Ganapa-thy, V., Chemical Engineering, Aug. 6,1984, p. 94. McGraw-Hill, Inc. All rights reserved.)...

Gas pipework in a user s premises serves the function of transporting the gas from the meter to the point of use in a safe way and without incurring an avoidable pressure loss. For low-pressure installations, the permitted pressure loss is only 1 mbar from the meter to the plant manual isolating valve at maximum flow rate. The pipework must be sized adequately to allow for this. Boosters are sometimes used to overcome pressure losses, but the use of a booster should never be considered a satisfactory substitute for correct design of pipe sizes. Where gas is available at higher pressures it may be permissible to tolerate pressure losses of more than 1 mbar. 

Fig. 4.1.6 HPLC analysis of a sample of purified natural aequorin on a TSK DEAE-5PW column (0.75 x 7.5 cm) eluted with 10 mM MOPS, pH 7.1, containing 2mM EDTA and sodium acetate. The concentration of sodium acetate was increased linearly from 0.25 M to 0.34 M in 14 min after the injection of the sample. Full-scale 0.02 A. Flow rate 1 ml/min. Reproduced with permission, from Shimomura, 1986a. the Biochemical Society.

Figure 9.22. Effect of catalyst potential, UWr, on conversion of acetylene (a) and selectivity towards ethene formation (b) with H2 C2H2=9 1. Conditions pH2-60 kPa, Pc2h2=7 kPa. pHe=34 kPa, total flow rate Fv=30.3 cm3 STP/min. UWr was initially set at +400 mV and was increased in steps until the maximum negative voltage was applied. Uwr was then returned to its original value of +400 mV and the open symbols correspond to measurements taken at this point.31 Reprinted with permission from Academic Press.

Figure 9.25. Transient effect of applied positive current (1=5 mA) on the rate of consumption of hydrogen (rH2) and oxygen (r0) gas molar flow rate fm=13x 0"s mol/s.35 Reproduced by permission of The Electrochemical Society, Inc.

Fig. 2.7 (d) Comparison between spray and micro-jet performance for two flow rates 50.56 ml/min [2.87 pl/mm s]. Parts (b-f) reprinted from Fabbri et al. (2005) with permission... 

Fig. 3.17 Average pressure drop reduction as a function of flow rate for a series of different surfaces in a micro-channel having dimensions W = 2.54 mm, H = 127 pm, and L = 50 mm. The experimental data include a series of ultrahydrophobic surfaces with a regular array of square micro-posts with d = 30 pm with a spacing between micro-posts of w = 15 pm represented by triangles (A), <7 = 30 pm and w = 30 pm represented by squares ( ), J = 30 pm and w = 60 pm represented by circles ( ), and d = 30 pm and w = 150 pm represented by diamonds ( ). Reprinted from Ou et al. (2004) with permission...

Fig. 5.11 Probability of appearance of different two-phase flow patterns at low liquid flow rates. Reprinted from Kawahara et al. (2002) with permission...

Figure 4.9 Schematics of electrospray LC-MS interfaces with (a) a heated capillary and (b) a heated block to allow high mobile-phase flow rates. From applications literature published by (a) Thermofinnigan, Kernel Hempstead, UK, and (b) Micromass UK Ltd, Manchester, UK, and reproduced with permission.

Figure 5.1 Pesticides included in the systematic investigations on APCI-MS signal response dependence on eluent flow rate the parameter IsTow represents the distribution coefficient of the pesticide between n-octanol and water. Reprinted from J. Chromatogr, A, 937, Asperger, A., Efer, 1., Koal, T. and Engewald, W., On the signal response of various pesticides in electrospray and atmospheric pressure chemical ionization depending on the flow rate of eluent applied in liquid chromatography-mass spectrometry , 65-72, Copyright (2001), with permission from Elsevier Science.

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