Joseph M. Genco Professor Calder Professor of Pulp and Paper Science and Engineering   • B.S. Case Institute of Technology, 1960 • M.S. Ohio State University, 1962 • Ph.D. Ohio State University, 1965   Phone: 207-581-2284 Fax: 207-581-2323 Email: genco@maine.edu

Research Interests

Oxygen delignification • refining • pulping • pulp bleaching

Current Research

Bond strength of Kraft Pulps Following Oxygen Bleaching

Oxygen delignification has emerged as an important processing technology for bleach plants in the 21st century. Understanding the effect of process conditions in an oxygen stage on fiber properties, especially inter-fiber bonding has great industrial significance; because inter-fiber bonding influences virtually all paper properties. The objective of this work is to investigate fundamentally how oxygen bleaching effects inter-fiber bond strength.

Filtration Resistance Determination of Fibrous Suspensions Utilizing A Rapid Drainage Tester

The drainage rate during sheet formation is a critical issue in the operation and the design of the wet-end of commercial paper machines. Previous attempts to correlate laboratory pulp drainage tests with pulp drainage on commercial paper machines have had limited success. In this work, a laboratory drainage tester has been developed to characterize the drainage of pulp slurries under industrial process conditions. Measuring the height change of the free surface of a suspension with a high-speed triangulation sensor permits continuous monitoring of the drainage rate. A leading manufacturer of paper machines is using the device to gather field data for the design of commercial paper machines.

High-Yield Alkaline Peroxide Chemi-Mechanical Pulping of Northeastern Hardwoods

The Alkaline Peroxide Mechanical Pulping (APMP) process has been shown to produce high quality pulp commercially from aspen and other low-density, high-brightness hardwoods. Difficulties have been encountered in applying the process to hardwoods typically found in the Northeastern United States due to their higher density and darker color. The objective of this work is to produce strong, bright APMP pulp from northeastern hardwoods. This research has shown that acceptable pulps can be produced from Northeastern hardwoods provide the wood chips are thoroughly impregnated with hydrogen peroxide and caustic prior to performing the size reduction and bleaching steps in the process.

Medium Consistency Oxygen Delignification Kinetics and Tower Design

This research involves development of a method for dimensioning medium consistency, up-flow oxygen reactors. The design model is use for sizing and predicting the lignin content and intrinsic viscosity of pulps following exposed to oxygen and caustic in medium consistency oxygen, up-flow towers. Process parameters controlling the size of the reactor are the pulp throughput and consistency, temperature, caustic charge, oxygen addition rate and oxygen pressure. Design calculations suggest that the delignification rate depend strongly on the temperature while the selectivity is primarily controlled by the caustic addition. The aspect ratio of the tower must be carefully controlled to avoid gas channeling.

Selected Publications

Book Chapters

J.M. Genco, "Pulp", Kirk-Othmer Concise Encyclopedia of Chemical Technology, Fourth Edition, pp. 1678-1682, John Wiley & Sons, NY, (1999).

S. Dixon, W. Miller, P. Bennett, and J.M. Genco, “Short Sequence Bleaching of Southern Softwood”, contained in Elemental Chlorine Free Bleaching, Katerine A. Kulas, Editor, pp. 195 - 221, Tappi Press, Atlanta (1999).

Genco, J. M., "Pulp," appearing in Kirk-Othmer Encyclopedia of Chemical Technology, Volume 20, 494 - 582 (1996).

Selected Papers

Paradis, M. A., Genco, J. M., Bousfield, D. W., Hassler, J. C. Hassler and Wildfong, V., “Measurement of Drainage Under Conditions of Known Shear Rate”, Journal of Pulp and Paper Science, 29(12), 395-400 (2003).

Wildfong, V and J. M. Genco, “An Examination of Two Hybrid Top-Wire Former Configurations for Producing Newsprint”, Tappi Journal, 2(10), 13-18 (2003).

van Heiningen, A., Krothapalli, D., Genco, J. M. and Justason, A., “Chemical Reactor Analysis of Industrial Oxygen Delignification”, Pulp and Paper Canada, 104(12) 96-101 (2003).

Borchardt, J. K., Genco, J. M., and Paradis, M. A., “Improving Digester Performance through the Use of Surfactants”, Pulp & Paper Canada,  Vol 104:2, T26-T29 (2003).

Guay, D. F., Cole, B. J., Fort, R. C., Genco, J. M. and Elder, T. J., “Mechanisms of Oxidative Degradation of Carbohydrates during Oxygen Delignification. Part III: Reaction of Photochemically Generated Hydroxyl Radicals with 1, 5-Anhydrocellobitol and Cellulose”, J. Pulp and Paper Science, 28(7), 217-221 (2002).

Zou, H., A. Liukkonen, B. Cole, J. Genco, and W. Miller, "Influence of Kraft Pulping on the Kinetics of Oxygen Delignification", TAPPI Journal, 83(2):65-71 (2000).

Snowman, V., J.M. Genco, B.J. Cole, W. Miller, “Bond Strength of Oxygen Delignified Hardwood Kraft Pulps”, Tappi Journal, 82(2), 103-109 (1999).

Miller, W. S., S. Agarwal, B.J.W. Cole, and J.M. Genco, “Kinetics of Oxygen Delignification”, Journal of Pulp and Paper Science, 25(10):361:366, (1999).

Agarwal, S., J.M. Genco, W. Miller, and B.J.W. Cole, “Medium Consistency Oxygen Delignification Kinetics and Tower Design”, in Innovative Advances in the Forest Products Industries, edited by Brian Brogdon, AIChE Symp. Series No. 319, 94, pages 32-46, 1998.

Blodgett, R., J.M. Genco and B.J. Cole, “Alkaline Peroxide Mechanical Pulping of Northeastern Hardwoods”, in Innovative Advances in the Forest Products Industries, edited by Brian Brogdon, AIChE Symp. Series No. 319, 94, pages 21-31, 1998.

Bennett, P.D., Turt, V., Genco, J.M., Jansson, S. and K. Loonberg, “Effect of Specific Edge Loading on Freeness Drop Coefficient”, pages 134 to 145, in Further Advances in the Forest Products Industry, Edited by Hart, P., AIChE Symposium Series, Vol. 93, 1997.

Agarwal, S.B., Genco, J.M., Kwon, H.B., and Cole, B.J.W., “Oxygen Delignification of Southern Hardwoods”, pages 26 to 41, in Further Advances in the Forest Products Industry, Edited by Hart, P., AIChE Symposium Series, Vol. 93, 1997.

Ransdell, J.C., Genco, J.M., DiNovo, S.T. and Cole, B.J.W., “Delignification of Shredded Spruce and Fir Wood Using Sodium Carbonate and Oxygen”, pages 7 to 19, in Further Advances in the Forest Products Industry, Edited by Hart, P., AIChE Symposium Series, vol. 93, 1997.

Arslan, K., Bousfield, D.W., and Genco, J.M., “Effect of Shear Forces on Fine Particle Retention”, TAPPI J., 80(1) 254-261 (January, 1997).

Guven, E., Genco, J., and Miller, W., “Medium Consistency Oxygen Delignification of Southern Hardwoods”, in Fundamentals and Applications in Pulping, Papermakiing, and Chemical Preparation, pages 10-28, AIChE Symposium Series 311, Vol. 92, 1996.

Juvekar, P., J. Ransdell, B. Cole, and J.M. Genco, , "Kraft Pulping Kinetics of Eastern White Cedar", Advances in Pulping and Papermaking, AIChE Symposium Series, Vol. 91, 1-18 (1995).

Mantar, E., A. Co, and J.M. Genco, "Drainage Characteristics of Pulp Slurries Under Dynamic Conditions," Journal of Pulp and Paper Science, 21(2), J44-J49 (1995).

Selected Conference Proceedings

Dang, Z., Genco, J. M., van Heiningen, A. R. P., and Cole, B. J. W., “Pulp Pretreatments for Improved Selectivity and Extended Oxygen Delignification”, Proceedings of the 2003 TAPPI Fall Technical Conference: Engineering, Pulping & PCE&I, Chicago, Illinois, October 26-30, 2003.

van Heiningen, A., Krothapalli, D., Genco, J. M. and Justason, A., “Chemical Reactor Analysis of Industrial Oxygen Delignification”, Proceedings of the 2003 Annual PAPTEC Meeting, Montreal, Quebec, Canada, January 26 to 30, 2003.

Zou, H., J. M. Genco, A. van Heiningen, B. Cole and R. Fort, ”Effect of Hemicellulose Content in Kraft Brownstock on Oxygen Delignification”, Proceedings of the 2002 TAPPI Pulping & Engineering Conference, San Diego, Ca, Sept. 7 thru 11, 2002.

Genco, J., M., Zou, H., Bennett, P. D., Bair, C., and Kachesfahani, S. “Kraft Borate Laboratory Cooks With Varying Sulfidity”, Proceedings of the 2002 TAPPI, Sept. 7 thru 11, 2002.

Johnson, D. A., Park, S., Genco, J. M., Gibson, M., Wajer, M. and Branch, B., “Hydrogen Peroxide Bleaching of TMP Pulps Using Mg(OH)₂”, Proceedings of the 2002 TAPPI Pulping & Engineering Conference, San Diego, Ca, Sept. 7 thru 11, 2002.