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D.B.Cohen
system. This major advantage is offset to some extent by higher volatile solids in the
process effluent with lower BOD removals. Loadings must also be reduced to about
one-tenth that of conventional plants (0.02-0.1 lb. BOD per day/lb. VSS). Thus detention
times and capital outlay per pound BOD removed must be increased proportionately.
The open tank pure oxygen system combines the benefits of high rate loadings with
the minimum sludge production characteristic of total oxidation systems. The
development of this system has been tested at Metro Denver since June, 1971 in a 5 GPM
flow through pilot plant, and will be scaled up to a 10 million gallon per day operation in
1972.
Table 2 compares the pilot plant test results with average operations parameters for
the Metro Denver system.
A comparison of these results with the criteria previously listed as required for an
"ideal" activated sludge system, reveals that five of the six required criteria have been
achieved with the pure oxygen system. The sixth criteria (cost savings) has yet to be
evaluated.
While a final evaluation of capital and operations cost savings that are possible with the
pure oxygen system must await the large scale plant trial scheduled for 1972, a
preliminary estimate of capital costs savings to be realized with the new technology has
been calculated (Table 3).
D.B.Cohen
system. This major advantage is offset to some extent by higher volatile solids in the
process effluent with lower BOD removals. Loadings must also be reduced to about
one-tenth that of conventional plants (0.02-0.1 lb. BOD per day/lb. VSS). Thus detention
times and capital outlay per pound BOD removed must be increased proportionately.
The open tank pure oxygen system combines the benefits of high rate loadings with
the minimum sludge production characteristic of total oxidation systems. The
development of this system has been tested at Metro Denver since June, 1971 in a 5 GPM
flow through pilot plant, and will be scaled up to a 10 million gallon per day operation in
1972.
Table 2 compares the pilot plant test results with average operations parameters for
the Metro Denver system.
A comparison of these results with the criteria previously listed as required for an
"ideal" activated sludge system, reveals that five of the six required criteria have been
achieved with the pure oxygen system. The sixth criteria (cost savings) has yet to be
evaluated.
While a final evaluation of capital and operations cost savings that are possible with the
pure oxygen system must await the large scale plant trial scheduled for 1972, a
preliminary estimate of capital costs savings to be realized with the new technology has
been calculated (Table 3).