About Me

Greg Mehos & Associates

4 Crusade Road, Westford, Massachusetts 01886

978-799-7311 (mobile)

My approach to consulting is to teach clients the fundamental principles of bulk solids storage and handling so that we can work as a team when solving powder handling problems or designing equipment.

PROFESSIONAL PROFILE

Chemical  engineer with extensive experience in bulk solids handling and processing in   the pharmaceutical and chemical industries, including drying, fluidizing,   feeding, dispersing, conveying, storage, extrusion, reacting, blending, granulating,   testing, and densifying. Expert on   handling and processing challenging materials such as carbon black and fumed   silica. Professional experience   includes manufacturing, research and development, consulting, and training. Spray drying knowledge includes bench,   laboratory, pilot, and commercial equipment. Author of subsection on powder flow and hopper and chute design in Perry’s   Chemical Engineers’ Handbook, 9th  edition. Licensed Professional   Engineer. American Institute of   Chemical Engineers Fellow.

QUALIFICATION SUMMARY

Powder   handling and processing

· Designed hoppers, bins, silos, transfer chutes, granulators,   and feeders for handling bulk materials handled in the chemicals, energy,   pharmaceuticals, biomass, and plastics industries. 

· Optimized flow properties of pharmaceutical   formulations.

· Determined causes of caking of pharmaceutical and   food powders and provided remedies.

· Developed patented air-assisted hopper for handling   powdered metals.

· Designed extension hopper that prevents compaction   of powder in gravimetric feeder so that desired powder discharge rate is   maintained during filling cycle.

· Developed new surge tank design for feeding fluffy   carbon black into pelletizing equipment; steady, uninterrupted discharge   improved pellet quality and reduced dust levels.

· Designed innovative moving bed reactors, heaters,   and dryers for processing powders.

· Designed, fabricated, and installed moving bed   conditioner for removing static charge from powders.

· Designed bins and feeders for handling lithium-ion   battery anode and cathode powders.

Process   development

· Developed and implemented continuous granulation   process at contract manufacturing organization (CMO).

· Designed and implemented pilot plant process for surface   modification of fine particles. 

· Designed moving bed induction heater process for   manufacturing highly conductive grades of carbon black.

· Designed, fabricated, and installed moving bed   conditioner for preventing static charge of powders.

· Co-inventor of continuous solvent-free process for   removing cannabinoids from cannabis. 

· Scaled-up spray dryer based process for attaching   polymers onto inkjet pigments, key accomplishment in the launch of new   products for printing companies.

· Designed and implemented pilot plant process for surface   modification of fine particles. 

· Reduced the cost of spray drying at toll   manufacturer by stretching capacity of existing process equipment.

Project management

· As project engineer, managed testing programs and   designed or recommended equipment for storage, handling, and processing of   bulk solids. 

· Successfully completed solids handling projects for   the chemicals, pharmaceutical, plastics, biotechnology, food, and energy   industries.

· Executed research and development activities through   stage-gate process.

· Evaluated CMO options and managed projects at   selected organizations.

Spray   drying

· Managed pilot plant for scaling up spray drying   processes for isolating emulsified solids.

· Established operating conditions for Buchi,   GEA/Niro, and Roberts Box spray dryers with evaporative capacities ranging   from 1 – 1,000 kg/hr.

· Developed novel method for improving flowability of   spray-dried powders.

· Stretched capacity of existing commercial spray   dryer by 40 percent.

Materials   science

· Established testing laboratory for measuring   fundamental flow properties of bulk solids.

· Evaluated and authored operating procedures for   Schulze, Peschl, Brookfield, and Freeman shear cell testers.

· Fabricated bulk solids permeability and wall   friction testers.

· Interpreted inverse gas chromatography (surface   energy) and sorption test results.

PROFESSIONAL EXPERIENCE

Greg Mehos & Associates LLC, Westford,   Massachusetts

Greg Mehos & Associates (www.mehos.net) provides   consulting, testing, and training services related to bulk solids handling   and processing. 2017 – present.

Jenike & Johanson, Inc.,   Tyngsboro, Massachusetts

Jenike & Johanson is a material testing and   engineering consulting company that specializes in the storage, handling, and   processing of bulk solids.

· Senior Project Engineer, 2014 – 2017

· Project Engineer, 2006 – 2011

Cabot Corporation, Billerica,   Massachusetts

Cabot is a specialty chemical company that   manufactures fine particles and inkjet colorants.

· Lead Engineer, 2011 – 2014

· Senior Process Development Engineer, 1996 – 2006 

Rohm and Haas Company, Bristol,   Pennsylvania

Rohm and Haas is a specialty chemical company that   produces acrylic monomers and polymers, ion exchange resins, and agricultural   products. It is now wholly owned by   the Dow Chemical Company.

· Senior Process Development Engineer, 1992 – 1996

· Process Development Engineer, 1989 – 1992

Massachusetts Institute of Technology   School of Chemical Engineering Practice Albany Station, Albany, New York,   Boulder, Colorado, and Cambridge, Massachusetts

The MIT Practice School is a program in which   chemical engineering graduate students work on projects at host companies (GE   Silicones, Waterford, NY, GE plastics, Selkirk, NY, Syntex Chemicals,   Boulder, CO) in lieu of a master’s thesis.

· Director and Assistant Professor, 1987 – 1989

· Assistant Director, 1986 – 1987 

University of Rhode Island Department   of Chemical Engineering, Kingston, Rhode Island

· Adjunct Professor, 2012 – present 

PROFESSIONAL AFFILIATIONS

· American Institute of Chemical Engineers Fellow;   past Chair, Boston local section; past Executive Committee Member, Particle   Technology Forum

· Institute for Briquetting and Agglomeration, Member,   Board of Directors 

· Licensed Professional Engineer, Massachusetts 

EDUCATION

· Ph.D. (Chemical Engineering), University of Colorado   

· M.Ch.E., University of Delaware

· B.S.Ch.E., University of Colorado, special honors

SELECTED PUBLICATIONS

Mehos,   G., S. Miller, and A. Godfrey, “Improving in Powder Flowability by   Spheronizing”, presented at the 37th annual Institute for   Briquetting and Agglomeration biennial conference, Denver, CO, September   2022.

Mehos,   G. and D. Patel, “Optimization of Oral Dosage Forms for Roller Compaction”,   presented at the 37th annual Institute for Briquetting and   Agglomeration biennial conference, Denver, CO, September 2022.

Mehos,   G., “Maximum Solids Discharge Rates from Hoppers”, Chem. Engr. Res. Des.,   191, 564 (2023).

Mehos,   G., “Design of Bulk Solids Moving Bed Heat Exchangers’, Chem. Engr. 127.   11, 28 (November 2020).

Mehos,   G., “Using Solids Flow Properties to Design Mass- and Funnel-Flow Hoppers”, Powder Bulk Engr., 34, 2 (February   2020).

Mehos,   G., “Choosing Agglomeration Technologies”, Powder Bulk Engr., 34, 1(January 2020).

Mehos,   G., “Using Powder Pumps in Wet Agglomeration Processes”, Powder Bulk Engr., 33, 1, 72 (January 2019).

Mehos,   G. and J. Carson, “Bulk Solids Flow and Hopper Design”, subsection in Perry’s   Chemical Engineers’ Handbook, 9th edition, McGraw-Hill, New   York, 2018.

Mehos,   G., “Designing Hoppers, Bins, and Silos for Reliable Flow”, Chem. Engr. Progress, 114, 4 (April   2018).

Mehos,   G. and S. McClory, “Gravimetric Feeders: The Achilles' Heel of Continuous   Manufacturing”, Powder Bulk Solids,   33, 4 (2018).

Mehos,   G. and C. Kozicki, “Choosing Agglomeration Processes”, Chem. Engr., 127, 8, 51   (October 2017).

Mehos,   G., M. Eggleston, T. Trautman, M. Freeman, N. Stevens-Murphy, “Using   Fundamental Powder Properties to Optimize the Flowability of Formulations”, Tablets & Capsules, 15, 7, 11   (October 2017).

Mehos,   G., “Prevent Caking of Bulk Solids”, Chem.   Eng. Progress, 112, 4 (April 2016).

Mehos,   G., and D. Morgan, “Hopper Design Principles”, Chem. Eng.,126, 1 (January   2016).

Mehos,   Gregory J., Feed Considerations for Continuous Dryers”, Pharm. Processing, July/August 2014, pp. 24-25.

Mehos,   G., A. Boroch, and C. Wykoff, “Using an Air-Assisted Discharge Hopper to   Eliminate Powder Flow Problems”, Powder   Bulk Eng., 27, 11 (November 2013).

Mehos,   G. and C. Kozicki, “Improving the Flow of Powders by Agglomeration”,   presented at the 32rd biennial Institute of Briquetting and   Agglomeration Conference, New Orleans, September 26, 2011 (Winner of the Neal Rice Award for best   paper and presentation).

Mehos, G. and J.   Paternina, “Design Considerations for Bulk Solids Gravity Flow Processing   Vessels”, presented at ChemInnovations, Houston, September 13, 2011.

Mehos,   G., “Designing Dust Collectors”, Chem.   Eng. Progress, 107, 9 (2011).

Mehos,   G. and C. Kozicki, “Consider Wet Agglomeration to Improve Powder Flow”, Chem. Eng., 121, 11 (January 2011).

Hartford,   C., G. Mehos, and S. Clement, “Caking Problems in Candy Manufacturing”, Manuf. Confect., 90, 12, 77 (December   2010).

Mehos,   G. and E. Maynard, “Handle Bulk Solids Safely and Effectively”, Chem. Eng. Progress, 105, 9, 38   (September 2009).

Mehos,   G., “Designing and Operating Gravity Dryers”, Chem. Eng., 116, 5, 34 (May 2009).

Mehos,   G., “Modifying Your Storage Vessel for Trouble-Free Continuous Purging or   Conditioning”, Powd. Bulk Eng., 21   (November 2008) and 22 (December 2008).

Jacobs,   K. and G. Mehos, “The Importance of Using Limiting Flow Rates to Assess the   Flowability of Pharmaceuticals, Excipients and Their Mixtures”, presented at   AIChE 2008 Annual Meeting, Philadelphia, PA, November 17, 2009.

Mehos,   G. and S. Clement, “Prevent Caking and Unwanted Agglomeration”, Chem. Eng, 115, 8, 55 (August 2008).

Ennis,   B. and G. Mehos, “Characterizing the Impact of Flow Aids on the Flowability   of Pharmaceutical Excipients by Automated Shear Cell”, presented at AAPS 2004   Annual Meeting, Baltimore, MD, November 10, 2004.

PATENTS

Mehos, G. and A. Boroch, “Mass Flow Hopper”, U.S. Patent No. 11,325,776B1 (May 10, 2022).

Sherwood, R., S. Sherwood, C. Cullimore, and G. Mehos, “Systems, Methods, and Equipment for Chemical Extraction”, U.S. Patent No. 10,765,965 B1 (September 8, 2020).

Mahmud, K, J. Belmont, James A, Y. Kutsovsky, W. Devonport, M. Wang, C. Galloway, and G. Mehos, “Polymers Containing Modified Pigments and Methods of Preparing the Same”, U.S. Patent No. 6534569 (April 13, 2003).

Mehos, G. and H. Tu, “Methods for Preparing Silica-coated Carbon Products”, U.S. Patent No. 6541113 (April 1, 2003). 

REFERENCES

David Worthen, Ph.D., J.D.

University of Rhode Island

College of Pharmacy

7 Greenhouse Road 

Kingston, RI 02881

Telephone: 859-433-5283

Email: drworthen@uri.edu 

Sheldon Davis, Ph.D.

Vice President of Research and Development

Guardian Industries

2300 Harmon Road

Auburn Hills, MI 48326

Telephone: 734-819-8757

Email: sdavis1@guardian.com 

Willie Hendrickson, Ph.D.

President

Aveka Group

2045 Wooddale Drive 

Woodbury, MN 55125

Telephone: 651-730-1729

Email: whendrickson@aveka.com