Treatment of Sugarbeet Wastes by Recycling
RONALD W. BRENTON, Junior Research Chemist
The Great Western Sugar Company
Loveland, Colorado
INTRODUCTION
More than 3 million tons of refined sugar are produced each year from
sugarbeets raised by independent growers in 29 states (1). In 1970-the industry's
centennial year—12 sugarbeet processing companies had 59 factories operating in 19
states. Within each factory the unit operations are quite similar; differences reflect
decisions on choices of equipment.
The operational processes required to handle and prepare the sugarbeets for
processing require considerable design adaptation to local environmental influences.
For instance the biological characteristics of the sugarbeets and the soil in which they
are raised varies vastly between the Imperial Valley of California and northern North
Dakota. The milder climates permit prolonged harvesting and processing of fresh
beets (up to in excess of 300 days per year) whereas harvest must be completed
quickly in the fall in the colder climates. In the latter instance the greatest
proportion of the harvest must be stored for processing and the length of operation
limited to 100-200 days due to an increasing rate of sugar losses with prolonged
storage.
It follows that one single conventional waste treatment scheme or design
cannot be adapted to each factory. The literature will show that almost all of the
typical waste treatment schemes have been used to treat sugarbeet waste water.
Hungerford (2) reported on work in Nebraska where large grass fields were
irrigated with factory wastes as a treatment method. Langen and Hoeppner (3)
described the use of activated sludge to treat sugarbeet wastes in Germany. Peterson
(4) reported on the use of trickling filters to treat a combination of municipal sewage
and beet sugar processing waste water.
One objective practice which has been increasingly successful in most areas is
that of recycling and reusing the waste water. Blankenbach and Willison (5) reported
on a recycled flume water system operating in Canada. Force (6) has reported on a
similar operation in Ohio. Numerous other recirculating systems have been
constructed but have not been reported in the literature. The practice of
recirculation reduces the overall water volume, reduces the amount of water
subjected to pollution thus reducing the size (and the cost) of facilities needed to
maneuver and treat the water.
McGinnis and Weckel (7) state that most of the beet sugar factories in the
United States recycle at least some of their process water in order to conserve fresh
water needs and reduce disposal requirements.
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