Frederick A. Zenz
Proessor Emeritus M.C.
NYS Lic P.E.
F.A. Zenz, Inc.
P.O. Box 49
55 Moffet Road
Cold Spring, NY 10516
Ph: 845-265-3066
Fax: 845-265-2720

  • Bachelor of Science in Chemistry, Queens College, 1942
  • Master of Chemical Engineering, New York University
  • Ph.D. in Chemical Engineering, Polytechnic University, NY
  • New York State P.E. License No. 43736
Current Positions
  • Independent Consultant January 1, 1962 to date
  • Professor Emeritus of Chemical Engineering at Manhattan College 1986 to date
  • Technical Director of Analogies In Matters of Science, Inc. 1989 to date
  • Staff Consultant to Pemm-Corp, 1975 to date
Societies, Activities, & Awards
  • Fellow of the A.I,Ch E.
  • Member of the American Chem. Soc.
  • Member of Amer. Nuclear Soc.
  • Life member of Sigma Xi; Tau Beta Pi
  • Kellex Key Award (Man. Proj.) 1945
  • AIChE Stephen L. Tyler award 1958
  • AIChE Chem. Engr'g. Practice award 1985
  • Personal Achievement award (Chem.Eng. p.111, 12/8/86)
  • Founder & Tech. Dir. of PSRI, 1969-1987
  • Vice President Engr'g., The Ducon Co., 1976-1982
  • IFPS distinguished lectureship award in pneumatic conveying, April 1998
  • Special Lecturer: N.Y.U., CCNY, Univ. of Utah, Univ. of Texas, Univ Col. London, Cambridge Univ
  • Adjunct Prof P.U.N.Y 1959-68, C.U.N.Y 1968-1969
  • AIChE Continuing Ed. Course in Fluidization 1969-1989
  • 2008 award as author of a groundbreaking book in Chem Engr'g published in the past 100 years of AIChE
  • Who's Who in Engineering
  • Who's Who in the East
  • Who's Who in the Atom
  • American Men of Science
  • Dictionary of International Biography XI
Employment History
  • 1942 - 1944 The M. W. Kellogg Co.
    Process development engineer in air fractionation plant design, absorption, distillation, and correlation of physical properties of hydrocarbons and industrial chemicals
  • 1944 - 1946 The Kellex Corp.
    Special Engr. detachment U.S. Army Corps of Engr's (UCCC Oak Ridge, TN) Analysis of diffusion cascade, power freq's., stage plugging, inleakage, etc., comp. design & prop's of UF6
  • 1946 - 1953 Hydrocarbon Research Inc.
    Process Engr. on NH3 plant designs, cat. poly., Socony Vac. TCC, Coal Gasif., H-Oil & H-Iron, C2H4 & C3H6 plants, etc. Development of tray designs, flat plate heat exchangers, riser reactors, seal leg design, new fluidized bed concepts, etc.
  • 1953 - 1956 The M. W. Kellogg Co.
    Development Engr. on fundamental studies in fluidization, entrainment, cyclone design, dipleg sizing, flared hole trays, light hydrocarbon separation equipment
  • 1956 - 1962 Associated Nucleonics - Stone & Webster Engr'g. Co.
    Mgr. Proc. Dept. & Staff Consultant, Proj. Mgr. Hvy. water sepn. plant, Chem. Warfare Service plant, LNG storage facilities, several nuclear power plants and isotope separation plants
  • 1962 - date
    Independent Consultant
Domestic and Foreign Clients Served since 1962
Petroleum (FCC, H-oil, Platforming, etc.)

Amerada Hess
Amer. Petrofina
Amer. Petr. lnst.
Ashland Oil
Atlantic Richfield
B.P. Oil Corp.
C.F. Braun
Caltex Petroleum
Chevron Res. & Dev.
Cities Service Oil
Energy Coop, Inc.
Exxon Res. & Engr'g.
Gulf Oil Corp.
Hydrocarbon Res. Inc.
M. W. Kellogg, Co.
Kerr - McGee
Mobil Oil Corp.
Phillips Petroleum
Pritchard Corp.
Std. Oil of Ohio
Stone & Webster
Sun Oil
Texaco Dev. Corp.
Texas City Refining
Total Petroleum
Lummus Co.
(Bapco, Bahrain)
(Commonwealth, P.R.)
(elf Aquitane, France)
(lmperial Ltd., Canada)
(Lagoven, Venezuela)
(Petrobras, Brazil)
(Petro Canada, Montreal)
(Promon, Brazil)
(E.I.L. New Delhi, India)

TiO2, PVC, PE, ACN, Melamine, Urea, NH3, Specialty Chems.

Alstom Power
American Cyanamid
J.E. Baker Co.
Cabot Titania
Celanese Chem. Co.
Chem Cat Corp.
duPont de Nemours
Ethyl Corp.
Formosa Plastics
BF Goodrich
GTE - Sylvania
Hydrite Chemicals
Intn'l Flav's. & Frag.
Melamine Chems.
Mallinckrodt (Calsicat)
Min Proc Engr's.
Mobil Chem. Co.
National Lead
Nepera Chem. Corp.
New Jersey Zinc
Olim Chemical Co.
Pittsurgh Plate Glass
Poly Plant Project, Inc.
Proctor & Gamble
Q.O. Chemicals (Gt. Lakes)
Reilly Tar & Chem.
Royce Chemical Co.
Scientific Design
SCM Pigments
Shamrock Technology
Stauffer Chem.
Stone Chem.
Suntech Group
Union Carbide Corp.
U.S. Gypsum
Union Camp
Urea Technology, Inc
Virginia Chems. Inc.
ISK Magnetics
Wilco Chem. Co.
(BP Chimie, Lavera, France)
(DSM. Netherlands)
(DynaMotive, Vancouver)
(European Vinyls, London)
(Gov't. of Israel, Jerusalem)
(I.C.I. England)
(Lonza, Milan, Italy)
(Naphtachimie, France)
(Neste Oy, Finland)
(Pechiney St. Gobain, France)
(Rhodia, France)
(Rhone-Poulenc, Lyon, France)
(Rhom, Darmstadt, Germany)
(Solvay, Brussels, Belgium)
(Snamprogetti, Milan, Italy)

Iron, Al, Tn, Mb, etc

Abex Corp.
Cleveland Cliffs
Cyprus Mines
Exxon Res. & Engr'g.
Hart Metals, Inc.
Haynes International
Kaiser Alum. & Chem.
Mercier Corp.
Natl. Beryllia Corp.
Newmont Gold
Qualitech Steel
Republic Steel
Reynolds Aluminum
Toth Aluminum
U.S. Steel
(Alcan, Arvida, Canada)
(BHP-Sivensa, Venezuela)
(FIOR de Venezuela)
(Met. Y. Chim. Mexico)
(Nucor. Trinidad)
(VAI, Linz, Austria)
(Nanomaterials, Israel)


Innov. Energy Global

Radioactive Waste

Coal, Coke, Wood, Shale, Heat Recovery, Incineration

ABB Combustion Engr'g
Aerojet Energy Conv. Corp.
Allied Chem. Corp.
Argonne Nat'l Labs
Babcock & Wilcox
Battelle - Columbus
Bechtel - America
Bethlehem Steel
Bituminous Coal Res., Inc.
Brown & Root
California Synfuels
Cogas Dev. Corp.
Dorr - Oliver
ENCON Associates
Energy Resources Corp.
Evergreen Energy
FMC Corp
Foster - Miller Associates
Foster - Wheeler
Hooker Chem Co.
Hydrocarbon Res. Inc.
Inst. of Gas Technology
International Paper
Jacobs Engineering
Keeler Dorr-Oliver
Rohm & Haas
Marquess & Nell
Midwest Res. Inst.
Noxso Corp.
Occidental Chem. Co.
Quaker Oats
Riley Stoker
Tampella. Ltd.
Thermo Electron Corp.
Tosco Vistron Corp.
(Forintek, Canada)
(lnternat'l. Energy Agcy., England)
(Midland Tar Distillers, England)
(Syncrude. Canada)

Trona, Cement, Silica, Silanes, Oxygen, H2SO4, etc.

Air Products & Chem's.
Allied Chem. Corp.
Amer. Messer Corp.
Armour Res. Foundation
Borden Chemical Co.
Burns & Roe
Cabot Corp.
Chem. & Indust. Corp.
Church & Dwight
DeSoto. Inc.
Diamond Alkali
Dow Chemical Co.
FMC Corp.
Foote Mineral, Inc.
General Electric, Co.
Hoechst - Uhde Corp.
NLO Industries
Passamaquoddy Technology
Potter Industries
Process Plants Corp.
Texas Instruments
Stearns Roger
Texas Gulf, Inc.
(C-I-L Canada)
(Elkem, Norway)
(Lafarge, France)

Food & Pharmaceuticals

Alpha Therapeutic
Cobe BCT
Hoffmann LaRoche
Mid America Dairymen
(Niro Atomizer, Denmark)

Law Firms

The Edwards Law Firm
Cravath, Swain & Moore
Folger &. Levin
Frost & Jacobs
Latham & Watkins
(Parlee McLaws, Edmonton)
Lucas & Just
Shearman & Sterling
Sprung, Horn, Kramer & Woods

Mat'l Hdlg., Vendors, Filtr,. etc

Amerex Corp.
AMF, Inc.
Burlington Industries
Butler Mfg.
Celgene Corp.
Combustion Equip. Corp.
Continental Can
CPC International
Dart Industries
The Ducon Co
E. G. & G. Idaho
Electric Power Res. Inst.
Environmental Res. & Engr'g.
Fluor Daniel
General Machinery
Hamilton Standard
Ind. Gas Clng. Inst.
Joy Mfg
Lever Bros.
Ludwig Cons. Engr's.
Mitre Corp.
Modar Corp.
Nordson Corp
Northern Natural Gas
Oak Ridge Natl. Labs.
Phillip Morris
Research Cottrell
Stock Equipment
(Katalistiks Amsterdam)


2,897,619 Snowfall Simulating Apparatus
3,139,069 Evaporating Apparatus
3,179,378 Apparatus for Mixing and Transporting Finely Divided Solids
3,410,055 Expandable Bed Filter and Method
3,606,946 Machined Components from Shavings by Ebullition
3,698,874 Dust Control Apparatus for Fluidized Bed Reactors
3,770,388 Granular Bed Reactor
3,800,508 Restrained Bed Filter-Reactor
3,826,738 Folded Transfer Line Reactor
3,912,466 Granular Media Filters
4,067,704 Granular Bed Filter
4,072,130 Apparatus and Method for Generating Steam
4,140,497 Screenless Granular Bed Filter
4,155,728 Screenless Granular Bed Filter
4,172,667 Method and Apparatus for Blending in a Fluidized Bed
4,260,298 Control of Solids Discharge from a Pressurized Vessel
4,947,803 Fluidized Bed Reactor Using Capped Dual-Sided Contact Units and Method for Use
5,033,413 Fluidized Bed Combustiuon System and Method Utilizing Capped Dual-Sided Contact Units
5,034,196 Particle Fractionator Employing Multiple Fluidized Bed Modules
5,368,824 Gas Distribution System for Fluidized Bed Reactors
5,656,243 Fluidized Bed Reactor and Process for Performing Reactions Therein

Books and Chapters therin
  1. "Fluidization", Chapter 3, Ed. by D.F Othmer, Reinhold, N.Y. 1956

  2. "Kirk-Othmer Encyclopedia of Chemical Technology", Chapter on "Absorbtion" in Vol. I, 2nd Edition; Chapter on Fluidization in 1st Edition, Supplement Vol. I; Chapter on "Fluidization" in 2nd Edition, Interscience, N.Y., 1957 - 1966; also 3rd Edition 1980

  3. "Fluidization and Fluid-Particle Systems", Reinhold, N.Y., 1960

  4. "Modern Chemical Engineering", Chapter 6 on "Fluid-Solid Systems", Ed. by A. Acrivos, Reinhold, 1963

  5. Editor of American Edition of "Hydrodynamics and Heat Transfer in Fluidized Beds", by S.S. Zabrodsky of the Inst. of Heat & Mass Transfer, Minsk, USSR, pub. by Scripta-Technica, Inc., N.Y. 1966

  6. "Fluidization and Related Processes", Chapter 3, pp.17-33, Pub’s & Info. Dir., New Delhi, India 1966

  7. "Fluidization", Chapter 1, Ed. by J.F. Davidson and D. Harrison, Academic Press, 1971

  8. "Research on Particulate Solids at PSRI", Section A.2, pp. 109-122 in Chem. Engr’g. in a Changing World, Ed. by W.T. Koetsier, Elsevier Pub. Co. 1976

  9. "Design of Gas Absorption Towers", Section 3.2, pp.3-50 to 3-108 in Handbook of Separation Techniques Ed. by P.A. Schweitzer, McGraw-Hill, N.Y. 1979

  10. "Cyclones", Chapter in the Encyclopedia of Chem. Processing and Design, Ed. by J.J. McKetta and W.A. Cunningham, Marcel Dekker, N.Y., 1982

  11. "State-of-the-Art Review and Report on Critical Aspects and Scale-up Considerations in the Design of Fluidized Bed Reactors", U.S.DOE NTIS Document DOE/MC/14141-1158(1982) and DOE/MC/14141-1304(1983)

  12. "Rheology of Particulate Solids", pp. 623-634, Handbook of Fluids in Motion, Ed. by N.P. Cheremisinoff and R.Gupta, Ann Arbor Science Publications, 1983

  13. "Fluidization Phenomena and Fluidized Bed Technology", pp 464-506; "Granular Bed Filters", pp.770-792, Handbook of Powder Science and Technology, Ed. by M.E. Fayed and L. Otten, Van Nostrand-Reinhold Co. 1984

  14. "Pneumatic Conveyors", pp. 1111-1176, Materials Handling Handbook, 2nd Ed., Ed. by R.A. Kulwiec, Wiley-Interscience, N.Y. 1985

  15. "Particulate Technology", Encyclopedia of Chemical Processing and Design, Ed. by J.J. McKetta and W.A. Cunningham, Marcel-Decker, Inc., Vol. 33, pp. 396-426, N.Y. 1990

  16. "Cyclone Separators" Chapter 11, API Pub. No. 931, Volume on Atmospheric Emmisions in Manual on Disposal of Ref. Wastes May 1975

  17. "P.S.R.I.", Particle Technology Research Review, Vol 1, pp. 149-152. March 1973

  18. "Cyclone Design", Chapter 12, pp.773-816, Fluidization, solids Handling and Processing, Ed. by W.C. Yang, Noyes Pub., 1999

  1. Limiting Capacity of Damped Tower Packings, Trans. AIChE, 41, No. 6, 693-710 (1945)

  2. Mechanism of Countercurrent Gas-liquid Flow Through Packed Towers, C.E.P., 43, No. 8, 415-428 (1947)

  3. Two-Phase Fluid-Solid Flow, Ind. Eng. Chem., 41, 2801-2806 (1949)

  4. Skirted Bubble Caps Provide Increased Bubbling Area, Chemical Processing, 13, 62, April 1950

  5. Screen Skirted Bubble Caps, Petroleum Refiner, 29, No.6, 103-105 (1950)

  6. What Goes on Inside Bubble Cap Towers, Chemical Engineering, 169-173, April 1952

  7. Volume of Liquid in Tilted Tanks and Drums, Chemical Processing, 156-158, July 1952

  8. Froth and Foam - The Bases for Tower Sizing, Petroleum Refiner, 32, No. 1, 150-154 (1953)

  9. Visualizing Gas-Solid Dynamics in Catalytic Processes, Petroleum Refiner, 32, No.7, 123-128 (1953)

  10. What Every Engineer Should Know About Packed Tower Operations, Chemical Engineering, 176-184, August 1953

  11. Calculate Capacities of Perforated Plates, Petroleum Refiner, 33, No.2, 99-102 (1954)

  12. Industrial Mathematics, Petroleum Refiner, 33, No.3, 179-180 (1954)

  13. A Mathematical Approach to Mixing and Internal Particle Circulation, Petroleum Refiner, 33, No.5, 203-204 (1954)

  14. Catalyst Team, Chemical Week, p.24, January 21, 1956

  15. Allowable Entrainment at Minimum Cost, Petroleum Refiner. 36, No.3, 179-181 (1957)

  16. Tray Design Saves Space, Chemical Engineering, 63, No.3, 132-134 (1956)

  17. How Solid Catalysts Behave, Petroleum Refiner, 36, No.4, 173-178 (1957)

  18. Minimum Velocity for Catalyst Flow, Petroleum Refiner, 36, No.6, 133-142 (1957)

  19. Nine Variables in Catalyst Flow, Petroleum Refiner, 36, No.7, 175-183, (1957)

  20. Find Best Particle Size Distribution, Petroleum Refiner, 36, No 5, 261-265, (1957)

  21. Calculate Fluidization Rates, Petroleum Refiner, 36, No.8, 147-155 (1957)

  22. Particle Size Affects Initial Fluidization, Petroleum Refiner, 36, No.9, 305-308 (1957)

  23. How to Predict Gravity Flow Rates, Petroleum Refiner, 36, No.10, 162-170 (1957)

  24. Contact Efficiency Influences Design, Petroleum Refiner, 36, No.11, 321-328 (1957)

  25. Nuclear Engineering for Consultants, Consulting Engineer, 10, No.3, 110-122 (1958)

  26. A Theoretical-Empirical Approach to the Mechanism of Particle Entrainment from Fluidized Beds, AIChE Jnl., 4, No.4, 472-479 (1958)

  27. New Chart for Packed Tower Flooding, Petroleum Refiner, 40, No.2, 130-132 (1961)

  28. Use Fluid Data for Solids Flow Rates, Petroleum Refiner, 41, No.2, 159-168 (1962)

  29. Minimize Manifold Pressure Drop, Petroleum Refiner, 41, No.12, 125-130 (1962)

  30. Flow of Fluid-Particle Suspensions from Liquid Fluidized Beds, I&EC Fundamentals, No.2, No.3, 194-199 (1963)

  31. Petrochemicals Lure Investment Dollars, Petro/Chem Engineer, 36, No.1, 28-33 (1964)

  32. Conveyability of Materials of Mixed Particle Size, I&EC Fundamentals, 3, No.4, 348-355 (1964)

  33. Determine Limits of Countercurrent Gas-Liquid Flow, H.P. & Petr. Ref., 44, No.3, 121-126 (1965)

  34. Incipient Bubble Destruction and Particulate Fluidization, AIChE Jnl., 11, No.3, 560-573, (1965)

  35. Non-Homogeneities in Solid-Liquid Fluidization, C.E.P., Symposium Ser., 62, No. 67, 42-50 (1966)

  36. Report on 5 papers on Heat Transfer in Granular Beds, 3rd Internat'l Heat transfer Conf., Vol. 6, (1966)

  37. Flowing Solids Displace Bubble Voids, Hydrocarbon Processing, 46, No.4, 171-175 April (1967)

  38. Find Sieve Tray Weepage Rates, Hydrocarbon Processing, 46, No. 12, 138-140. December (1967)

  39. Bubble Formation and Grid Design, Proceedings of the Tripartite Chem. Engr'g, Montreal, Sept. 25, 1968; Institution of Chem. Engr's. (London) Symposium Series No. 20, pp. 136-139

  40. Gas Distribution and Grid Design, NPRA Question & Answer Session on Refining Technology, p. 86, (1970)

  41. The Shallow Expandable Bed - A Versatile Processing Tool, AIChE Symp. Ser. vol. 67, No. 116, 245-250 (1971)

  42. The Chemical Engineering Consultant; An Industrial Detective, The School Science Review, Pub. by the Instn. of Chem. Engr's. (London), Part I, 52, No. 181, pp. 772-781, June 1971; Part II, 53, No. 182, pp. 94-102, Sept. 1971; Pat III, 53, NO. 183, pp. 284-292 December 1971

  43. Find Attrition in Fluid Beds, Hydrocarbon Processing, 50, 103-105, February (1972)

  44. When are Fines in Equilibrium, Hydrocarbon Processing, 51, No.2, 104-106, February (1972)

  45. The Evolution of Granular Beds for Gas Filtration and Absorption, Brit. Chem. Engr?g. & Proc. Tech., 17, No.3, 224-227, March (1972)

  46. Designing Gas Absorption Towers, Chemical Engineering, pp. 121-138, November 13 (1972)

  47. Granular Bed Filtration of an FCC Regenerator Effluent Stream, C.E.P., 69, No. 5, pp. 67-71 June (1973)

  48. A Theoretical-Empirical Approach to Saltation Velocity in Cyclone Design, AIChE Symp. Ser., No. 137, Vol. 70. 338-397 (1974)

  49. Help from Project EARL, Hydrocarbon Processing, 53, No.4, 119-124, April (1974)

  50. Size Cyclone Diplegs Better, Hydrocarbon Processing, pp. 125-128, May (1975)

  51. Particle Conveying in Extrusion Flow, Fluidization Technology, Vol. II, pp. 151-158, Ed. by D.L. Keairns, Hemisphere Pub., Wash. (1976)

  52. Bulk Solids Efflux Capacity In Flooded and Streaming Gravity Flow, ibid., pp. 239-252

  53. How Flow Phenomena Affect Design of Fluidized Beds, Chemical Engineering, pp. 81-91, December 19, 1977

  54. The Fluid Dynamics of Bubbling Beds, The Fibonacci Quarterly, 16, No.2, 171-183, April (1978)

  55. Studies of Attrition In Fluid-Particle Systems I, II, NSF Workshop, Rensselaer Poly. Inst., Troy, N.Y. October 17-19, (1979)

  56. The Gravity Flow of Gases, Liquids and Bulk Solids, I&EC Fundamentals, 18, No.4, 345-348, (1979)

  57. Pressure Loss in Horizontal-to-Vertical Upflow Elbows, Pneumotransport "5", BHRA, Cranfield, Bedford, England, January (1979)

  58. Studies of Attrition Rates in Fluid-Particle Systems via Free Fall, Grid Jets and Cyclone Impact, Journal of Powder and Bulk Solids Technology, 4, Nos. 2/3, 12-20 (1980)

  59. Particle Entrainment from Bubbling Fluidized Beds, Fluidization, Ed. by J. Grace and J. Matsen, Hennicker, N.H., August 1990

  60. Scale-Up Fluid Bed Reactors, Hydrocarbon Processing, 155-156, January 1982

  61. Exploratory Investigations of Vortex Length and Cyclone Pressure Drop, Hydrocarbon Processing, pp. 87-90, June 1983

  62. Particulate Solids - The 3rd Fluid Phase in Chemical Engineering, Chemical Engineering, pp. 61-67, November 28, 1983

  63. Flow Phenomena in a 2-Dimensional Fluidized Bed, Powder Technology, 38, No. 2, 101-106, May/June 1984

  64. Riser Design Considerations Under Slug Flow Conditions, Powder Technology, 38, pp. 205-210 (1984)

  65. Pressure and Additive Effects on Flow of Bulk Solids, I.& E.C. Proc. Des. & Dev., 3, 318-355, October 1964

  66. Evaluating Cyclone Efficiencies from Stream Compositions, Chemical Engineering, pp. 69-73, April 30, 1984

  67. Conveyability and Powder Classification, Proceedings of the Annual Powder & Bulk Solids Conf., pp. 396-407, pub. by Internat'l. Powder Inst., London, May 15-17 1984

  68. Transport Process and Phase Equilibria in Particulate Solid Systems, Proceedings of the CODATA Conf., Jerusalem, Israel, June 1984

  69. Standpipe Flow, Bubbling Aeration and Catalyst Characterization, pp. 1:1 to 1:17 in Proceedings of the 5th Annual Fluid Cat Cracking Symposium, Vienna, Austria, pub. by Katalistiks, Amsterdam, The Netherlands, May 23-24 1984

  70. Pneumatic Conveying from Grains to Powders, pp. 63-81, Proceedings of Pneumotec 2, Internat'l Conf. on Pneumatic Conveying Technology, Univ. of Kent, Canterbury, England, September 4-6, 1984

  71. Maintaining Dense Phase Standpipe Downflow, Powder Technology, Vol. 47, No.2, 105-113, 1986

  72. The Particulate Nature of the Universe, Chem. Eng. Communications, Vol. 62, pp. 123-133, 1987

  73. The Dual-Sided Multi-Riser AFBC Concept, Proceedings of the 10th Internat?l Conf. on FBC, ASME, San Francisco, Vol.2, 1025-1030, May 3, 1989

  74. Supercritical Phase Behavior of Fluid-Particle Systems, 6th Internat'l. Fluidization Conf., Banff, Alberta, Canada, pub. in Fluidization VI, pp. 121-128, May 7-12, 1989

  75. FCC Cold Modeling Helps Solve FCC Standpipe Flow Problems, 6th Internat'l. Fluidization Conf., ibid pp. 145-152

  76. The Saturation Dilute Phase Concentration of Matter, Chem. Engr?g. Communications, 116, 89-96, 1992

  77. Solve All Column Flows with One Equation, C.E.P., 93-98, October 1992

  78. Air Lift Pumps and Two-Phase Upflow, C.E.P., 51-56, August 1993

  79. Correlating Throughput and Backmixing in Fluidized Beds, Hydrocarbon Processing, 81-87, January 1995

  80. Optimize Performance of Fluidized Bed Reactors, C.E.P., 91, No. 4, pp.32-36, April 1995

  81. The Flooding Equation for Gas-Solids Contacting, Proceedings of the Ichea P-2 Conf., Florence, Italy, April 15, 1995

  82. A Universal Quantity, Chemtech, 26, No.9, pp. 19-22, September 1996

  83. Predicting the Degree of Particle Refluxing In Cocurrent Upflow Risers, Powder Technology, Vol. 97/2, pp. 146-150, June 15, 1998

  84. Correlating Particle Critical Velocities, Powder Technology, Vol. III, pp. 19-24 (2000)

  85. Developments in Elbow and Feedpoint Loss in Pneumatic Conveyors, Internat'l. Jnl. Powder Handling & Processing, 12, No. 3, 247-252 (2000)

  86. Cyclone - Design Tips, Chemical Engineering. 60-64, January 2001

Resume Addenda

Specifically with respect to past and present involvement in scale-up:

  1. Development of a scale up procedure based on fundamental experimentation and research and 62 years of industrial experiences which is recorded in several Research Papers to date proprietary to members of AIMS (e.g. duPont, Rhodia, Conoco-Phillips, etc.). Some portions thereof have been published in various journals and in my 1989 book.
  2. My predictions to clients that their scaled up reactor will not perform to the design yield or conversion (based on 1. above). Instances in which the remedies would be so costly that the processes were abandoned and the plants sold for scrap or other possible uses.
  3. Feasible revisions to clients’ designs (as always based on 1. above) which resulted in achievement of the desired performance in either conversion or capacity.
  4. Scale up from 1” to 4” pilots to reactors 20 feet and greater in inside diameter.
In category 2. There are two that come immediately to mind; each had involved investments in the order of 200 million dollars, with an estimated equal cost for the necessary revisions. One involved a pair of 30’ diameter vessels in connection with a new process for making furfural. The other was a new process for maleic anhydride. In both cases the original scale ups and designs were out-sourced to major engineering companies whose managements relied solely on their own in-house staff.

In category 3. I recall in particular 2 transfer, or “riser”, reactors in petroleum cracking; a black liquor oxidation and carbon recovery process; a hydrogen production unit currently under test; a terephthalic acid recovery unit; a formed coke unit for a blast furnace; two iron carbide plants; an isobutane dehydrogenation plant; a niacin reactor; a furfural production unit; etc.

In category 4. I recall two Trona ore “reactors” (sesquihydrate to monohydrate); an ammoxidation reactor to produce acrylonitrile; another for oxychlorination of ethylene to produce vinyl chloride monomer; gas phase polymerization of ethylene; chlorination of rutile for food grade fumed silica; etc.

Specifically with regard to particle-gas separation:

I have designed equipment for separation of fine particles associated with fluidized bed processes in petroleum cracking, coal combustion and gasification, fluid coking, fumed silica production and a wide variety of petrochemical and mineral processing plants. Clients and materials involved are listed in the accompanying resume.

I have designed cyclone systems installed in several major refineries and have for decades conducted more research in cyclone design than all major vendors combined. AIMS has carried the optimization of cyclone dimensional details for peak efficiency into an ultimate science.

In connection with such as Westinghouse, The Ducon Co., the U.S. D.O.E., Mobil Chemical, Exxon, Pall and Fuller Co.s I have designed granular bed filters, venturi scrubbers, porous metal and bag filters. Much of this background is covered in Chapters 11 and 12 of my 1989 book and among patents listed in my resume.

Specifically with respect to the field of pneumatic conveying, F. A. Zenz has industrial experience in design of pneumatic conveying systems in hundreds of installations handling two-phase systems of gas-solids and gas-liquids. These systems have covered broad areas:

  • In the case of dry solids — with air, hydrogen, steam, and other gases

    • Particulates consisting of sub-micron fumed silica; 1 to 2 micron pigments; avg. 17 micron Portland cement; 10 to 200 micron silica alumina catalyst carriers; several thousand micron crushed limestone, crushed coals, iron ores and polyethylene pellets.
    • Line Sizes ranging from 1/8th inch i.d. for nano materials and micro reactors, to 3” to 10” in-plant conveying lines, to 4 ft and 5 ft i.d. lines in petroleum processes such as for example Fluid Catalytic Cracking units and Fluid Cokers
    • Line Lengths varying from 100 to 800 feet in chemical plant handling

  • In the case of liquids - with air, hydrogen, CO, nitrogen and assorted gases

    • System conditions ranging in pressures from 15 to 3000 psig and up to 1500 degrees Fahrenheit
    • Liquids consisting of water, petroleum products and heavy oils in every physical form of two-phase flow.
    • Line sizes ranging from 5/8th inch to 10 inch i.d.
    • Line lengths — 3000 to 40,000 feet

In every case pressure drops were calculated for several pipe sizes, at several conveying rates and gas velocities to determine the optimum (minimum operating cost) size, followed by design or at least specification of the feed system, as well as design of the end separator as hydroclones, cyclones, filters etc.


AIMS, an acronym for Analogies In Matters of Science, incorporated in January 1989, is a non-profit New York State corporation engaged in fundamental and innovative applied research into all aspects of multiphase fluid dynamics, ranging from the mechanics of material handling through phase contact and scale-up in chemical reactor design. Through affiliation with the shops and laboratories of Pemm-Corp, AIMS offers not only developing design thtory, but also fabrication and experimental testing of existing and new technologies. Priorities in the subjects and directions to be taken by AIMS are dictated by the membership and reported upon at semi-annual meetings usually held at the Pemm-Corp facilities. AIMS’ technical director has over 60 years experience in design, trouble shooting, and revamping of, for example, nearly every fluidized bed process in the petroleum and petro-chemical industries; he has authored two books and over 100 published papers. Since 1975 Pcmm-Corp has similarly served as the facility for developing, testing and designing grids, baffles, cyclones and ancillary equipment particularly in fluidized bed reactors for such as duPont, Exxon, Texaco, Allied Chemical, Valero Petroleum, Chevron, Nucor, Phillips Petroleum, D.S.M., I.C.I., Great Lakes Chemical, Lummus-Lonza, Snamprogetti, etc., etc.

From the point of view of an academician; a research, design, or development engineer; or a plant operator, a most significant result of AIMS’ research is reflected in its title as deriving from Analogies. The correlants of much engineering design data take the form of well recognized Reynolds numbers, friction factors, Nusselt numbers, vapor pressures, etc. AIMS has experimentally demonstrated by analogies, that in these correlants temperature in the case of molecules can be replaced with velocity in the case of particles, molecular weight with particle size, melting point with incipient fluidizing velocity, boiling point with terminal velocity, vapor pressure with saturation concentration in the dilute phase, relative volatility with relative elutriability, etc. Similarly directly replacing the properties of liquids (the dense phase of molecules) with the properties of bulk powders (the dense phase of particles) in the dimensionless equation for gravity flow was found to correlate all regimes of two-phase cocurrent and countercurrent flows whether in open, packed, or baffled conduits as well as reaction vessels in scale-up to any dimensions. Along with recognizing and determining the angular shear plane in liquids as directly equivalent to the more recognized angle of draw, angle of internal friction, angle of nip, wedge of maximum thrust, etc., characteristic of bulk solids, AIMS’ innovative approach reduces a host of empiricisms from divergent disciplines into a common universal comprehension of the causative physical phenomena.

Availability of personnel and equipment, and hence breadth and pace of AIMS’ investigations are substantially dependent on the financial support by member companies. Current nominal dues are $7,000/year for a 5 year contract commitment. To date the technical director has served without compensation; dues are used solely to fund experimental work, reproduction of reports, and mailing costs; writing of reports and correlation of data are carried out by the technical director.

A total of 79 proprietary reports referred to as Research Papers issued to date, represent ~1100 pages of text and Figures replete with cited industrial experiences and sample calculations, along with a subject index, issued periodically to all members.

On occasion, usually through cooperation with a member company, some aspect of AIMS’ work is submitted to a journal for publication. A sampling can be found in:

Powder Technology, Vol. 111, pp. 19-24, 2000
Powder Technology, pp. 146-150, June 1998
Hydrocarbon Processing, pp.81-87, January 1995
Chem. Engr’g. Progress, pp. 93-98, October 1992

You are most cordially invited to join and participate in AIMS’ continuing pursuit of the fundamentals in the behavioral science of molecular and particulate matter as it contributes to innovative engineering design in the process industries.

A membership contract is obtainable by letter or Fax (or e-mail: to the attention of F. A. Zenz, President and Technical Director at P.O. Box 49, Cold Spring, N.Y. 10516.

Ph 845 - 265 - 3066
Fax 845 - 265 - 2720

Frederick A. Zenz
Pres. and Tech. Dir.

Analogies In Matters of Science, Inc.
P0. Box 49
55 Moffet Road
Cold Spring, N.Y. 10516