Section Eight
FOOD WASTES
59    DESIGN AND OPERATION OF A CRANBERRY
WASTEWATER TREATMENT SYSTEM
Frederic C. Blanc, Professor
James C. O'Shaughnessy, Associate Professor
Department of Civil Engineering
Northeastern University
Boston, Massachusetts 02115
Ken Carlson, Project Manager
Paul Weisman, Vice President
LEA Group Engineers/Architects/Planners
Boston, Massachusetts 02111
INTRODUCTION
Cranberries are a major agricultural crop in Massachusetts and a few other states. During the six to
eight week harvest season, the cranberries are delivered to cranberry receiving facilities which wash
and sort this fruit to prepare it for shipping or processing. This paper presents information on how
such a seasonal cranberry receiving wastewater is being treated at a new cranberry receiving facility. It
includes the results of treatability studies and pilot studies performed for the aerated lagoon —land
application treatment system which was selected as well as design information and first season
operational data for the aerated lagoon operation.
PROCESS OPERATIONS
Cranberries which are marketed as fresh fruit and are picked dry represent only a small portion of
the total harvest. The bulk of the fruit is hydraulically harvested from flooded bogs. This water-
harvested fruit is brought into the receiving station by truck, weighed on a truck scale, and dumped
into a bulk holding tank or directly into a conveyor type system which leads to the cleaning operation.
Most of the water from the hydraulic harvesting operation has drained from the truck by the time it
arrives at the receiving station; however, the fruit is still wet. In addition to water, the berry surface is
also coated with a slime layer of fine soil particles, algae, and other matter. The bulk of water-
harvested fruit also contains pieces of vines, tiny leaves, and other grit-like debris which must be
removed before storing or processing the fruit into juices or sauces.
Processing operations at a cranberry receiving location consist of physical and hydraulic operations
which remove dirt and other matter from the fruit. Flumes, vibrating and rotating screens, brushes,
and spray type rinses are all used to clean the berries. A good amount of the process water used in the
receiving operation is recirculated during the day.
Such processing operations produce the bulk of the wastewater from the receiving operation.
Additionally, there are drippings from solid waste storage areas, the truck receiving area, and discarded damaged berries. Such wastes are generally low in volume but high in strength.
WASTEWATER CHARACTERIZATION
To obtain the wastewater characteristics and treatability information for the wastewater treatment
design of a receiving facility to be constructed, treatability studies and a waste sampling program were
conducted at an existing receiving facility during the 1984 harvesting season. Total water usage and
individual wastewater flows associated with fruit receiving operations were measured and sampled.
Based on this sampling program, a profile of cranberry receiving wastewater was constructed. The
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