Production of Vitamin B-12 from
Milorganite
RAY D.  LEARY
Chief Engineer and General Manager
Sewage Commission of the City of Milwaukee
Milwaukee, Wisconsin
For over 25 years the sewage disposal in Milwaukee has been
accomplished by a method known as the Activated Sludge process.
Milwaukee was a pioneer in the development of this process, and was
the first municipality to convert the waste solids of sewage into a
high grade all organic fertilizer.
Before the treatment plant was constructed, a pilot plant was
operated for a number of years to determine the feasibility of the
Activated Sludge method, and to investigate the waste sewage solids
produced as to its fertilizer value. A research fellowship was then
established at the soils department of the University of Wisconsin to
undertake the initial study of the dry solids as fertilizer material. Work
was conducted in the laboratory and greenhouses, and many field plots
were established to compare activated sludge with other organic sources
of nitrogen and also with inorganic materials. Tests were made on
corn, potatoes, vegetable crops, grain, etc., as well as trials on lawns,
golf courses, etc. The fellowship was terminated at the end of four
years, after establishing the value of Milwaukee's waste activated
sludge as a fertilizer.
The Sewerage Commission of the City of Milwaukee then decided
to convert the waste activated sludge into an all organic fertilizer and
coined the word "Milorganite" as the best one suited for its product.
When the need for trace elements by growing plants was demonstrated by agricultural research, arrangements were made to have a
complete analysis of Milorganite made because it was felt Milorganite
was sure to contain trace elements in an appreciable amount. The
analysis was made at the soils department of the University of Wisconsin. After results confirmed the presence of trace elements, the
next step was to determine their availability for use by plants. Another
fellowship, also at the soils department of the University of Wisconsin,
was established covering a two year period.   The results proved that
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