33    BIOLOGICAL TREATMENT OF MANGANESE FROM
MINING SEEPAGE-PILOT PLANT STUDIES
John A. Gordon, Professor
Civil Engineering Department
Tennessee Technological University
Cookeville, Tennessee 38505
Nai-Syun Chuang, Environmental Engineer
Peer Consultants
Oak Ridge, Tennessee 37830
INTRODUCTION
Packed column, biological treatment of manganese is in a process of development as reported by
recent papers by Gordon,1 Gordon and Burr,2 and Gordon, Chuang and Wallace.3 The general
concept is to have manganese-depositing bacteria grow on fixed media within a column receiving a
supply of soluble manganese-laden water. The bacteria are expected to oxidize the soluble manganese
to insoluble manganese dioxide according to Equation 1.
2Mn2 +  + 02 + 2H20 - 2Mn02 + 4H +
(1)
Erlich4 reported that the bacterial nature of the manganese fixation process involves adsorption of
Mn2 + to the cell followed by oxidation and precipitation. The cell can derive energy from the
oxidation as ATP, but no such bacteria have been grown in a strict autotrophic environment. The
biological activity is heat-labile and inhibited by poisons such as HgCl2, CaCl2, KCN, NaN3, and
benzene. Ghiorse5 detailed similar characteristics for Mn2 +-oxidizing bacteria.
EXPERIMENTAL RESULTS
The data obtained by the writers while studying several 4-inch diameter columns packed with glass
marbles, chert, and sandstone were combined and the fraction of manganese remaining was modeled
as a function of the applied mass loading. Figure 1 shows the data and the parabolic line of best fit. A
linearization of the data gave Equation 2 which had an R2-value of 0.59. Thus, the parabolic mass
loading model explained about 60% of the variation in the data.
*
LEGEND
o INFLOW CONCENTRATION
c OUTFLOW CONCENTRATION
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...«..,,
S3
Is
z "
o a
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a
jT
s
VyV\
r
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Figure 1.    Fraction of manganese remaining as a     Figure 2.   The results of a poisoning study on a
function of the mass loading based upon lab- column to show the bacterial nature of the
oratory studies. removal.
44th Purdue Industrial Waste Conference Proceedings, © 1990 Lewis Publishers, Inc., Chelsea, Michigan 48118.
Printed in U.S.A.
299