Ozonation of dissolved organic matter in substrate-varied and operationally-varied activated sludge effluents

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1984

OSTI ID:6236122

Watt, R D

The dissolved organic matter in activated sludge effluents includes microbial by-products, so manipulating bioreactor variables could indirectly affect downstream processes. This research studied ozonation and ozonated effluent character as affected by three activated sludge variables. These variables were each tested at two levels, including pH levels of 6.0 and 8.0, dissolved oxygen (DO) levels of 1 and 7 mg/L, and organic substrates of complex and simple compositions. All eight possible combinations of these levels were tested in laboratory reactors, yielding eight long-term composite samples, which were then filtered and adjusted to pH 7. Data from the unozonated samples showed that complex feed, a pH of 8, or a DO of 7 mg/L had resulted in higher organic levels. Molecular size and adsorption tests indicated that the bioreactor variables had also influenced the qualitative character of effluent organics. The relative ozone demand of each sample was measured by a test that found the ozone dose required to yield a dissolved ozone residual of 0.30-0.35 mg/L after five minutes of mixing in a gas-liquid batch reactor. Resulting doses ranged from 3 to 16 mg/L and correlated to organic level, especially after accounting for nitrite. Another test measured ozone consumption rates. The data fit pseudo-first-order kinetics that were modified by replacing the rate constant by a rate-constant function, which decreased as ozone was consumed. Sample comparison suggested that kinetic behavior was also related to organic and nitrite levels.

• Research Organization: Purdue Univ., Lafayette, IN (USA)
• OSTI ID: 6236122
• Country of Publication: United States
• Language: English

Related Subjects

520200* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
ACTIVATED SLUDGE PROCESS
ADSORPTION
BIOREACTORS
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
DATA
DISSOLVED GASES
ELEMENTS
EXPERIMENTAL DATA
FLUIDS
GASES
INFORMATION
KINETICS
LIQUID WASTES
MANAGEMENT
NITRITES
NITROGEN COMPOUNDS
NONMETALS
NUMERICAL DATA
ORGANIC MATTER
OXYGEN
OXYGEN COMPOUNDS
OZONE
OZONIZATION
PARAMETRIC ANALYSIS
PH VALUE
PROCESSING
REACTION KINETICS
SLUDGES
SOLUTES
SORPTION
WASTE MANAGEMENT
WASTE PROCESSING
WASTES