Fixed Film Biological Process Solves Pulp Mills Wastewater Treatment Need, 1995 Environmental Conference Proceedings

Doug Marshall

Dexter Nonwoven Division

Tom Schultz

Envirex, Inc.

Angelo Zeni

Dexter Nonwoven Division

William J. Crabb

Envirex Inc.

Dexter Nonwovens, a pulp and paper mill located in Windsor Locks, CT was required by a federal consent order, to install a biological treatment system for its pulp mill wastewater discharge.

In evaluating various potential biological treatment technologies, Dexter performed an in depth analysis of each technology comparing factors such as land requirements, ease of operation, flexibility to waste flow and load variations, etc. From this analysis, two(2) new and innovative fixed film biological treatment technologies were selected to perform pilot treatability studies; a Fluidized Bed system and a Submerged Biological Contactor system. Following the pilot study, the Submerged Biological Contactor system was selected as the preferred technology. After nearly two(2) years of full scale operation, the Submerged Biological Contactor treatment system has proven to be very accommodating of wide fluctuations in wastewater flow and strength while at the same time requiring a minimal amount of operator attention. This paper will outline the criteria under which the fixed film Submerged Biological Contactor technology was selected and how the system is actually performing on a full scale basis.