Sequential nitrification-denitrification in a plug flow activated sludge system /

Mode of access: Internet.

Study of activated sludge separation by dynamic straining /

Mode of access: Internet.

Applicability of two mathematical models to the batch settling of activated sludge.

"Supported by Federal Water Pollution Control Administration, U.S. Department of the Interior. Research project WP-01011."

The effect of sludge characteristics upon the flotation of bulked activated sludge /

Vita.

Uptake of soluble phosphate by activated sludge /

"Supported by Federal Water Pollution Control Administration ... research fellowship F1-WP-21, 616, and Ford Foundation."

The effect of induced flocculation on the settling and thickening behavior of activated sludge /

"Supported by U.S. Public Health Service Traineeship EH66-616 and U.S. Dept. of Interior Research Project WP 01011-01."

Applicability of prevailing gravity thickening theories to activated sludge /

Vita.

Biochemical storage phenomena in activated sludge /

Dissertation University of Illinois.

Flocculation and clarification in activated sludge systems /

Vita.

The influence of ultrasonic vibrations upon the physical features of activated sludge.

Thesis (M.S.)--University of Illinois.

Changes in some physical properties of activated sludge under different biological loading conditions.

"Supported by Federal Water Pollution Control Administration Research Grant WP 1011."

Ultraviolet disinfection of activated sludge effluent discharging to shellfish waters /

Mode of access: Internet.

The fertilizer value of activated sludge

Mode of access: Internet.

Phylogenetic and physiological characterization of a heterotrophic, chemolithoautotrophic Thiothrix strain isolated from activated sludge

The sheathed filamentous bacterium known as strain CT3, isolated by micromanipulation from an activated sludge treatment plant in Italy, is a member of the genus Thiothrix in the gamma-Proteobacteria according to 16S rDNA sequence analysis. The closest phylogenetic neighbours of strain CT3 are strains I and Q(T), which were also isolated from activated sludge and belong to the species Thiothrix fructosivorans. These strains have respectively 99.2 and 99.4 % similarity to CT3 by 16S rDNA sequence comparison. CT3 shows 63-67 % DNA-DNA hybridization with strain I, which is the only currently viable strain of T. fructosivorans. CT3 is the second strain in the genus Thiothrix that has been shown to be capable of growing autotrophically with reduced sulfur compounds as the sole energy source; autotrophy was also confirmed in strain I. The first reported chemolithoautotrophic isolate of this genus was a strain of 'Thiothrix ramosa' that was isolated from a hydrogen sulfide spring and is morphologically distinguishable from all other described strains of Thiothrix, including CT3. CT3 is an aerobic organism that is non-fermentative, not capable of denitrification and able to grow heterotrophically. Autotrophy in the genus Thiothrix should be investigated more fully to better define the taxonomy of this genus.

Flow regime, hydrodynamics, floc size distribution and sludge properties in activated sludge bubble column, air-lift and aerated stirred reactors

This paper presents a comparative study how reactor configuration, sludge loading and air flowrate affect flow regimes, hydrodynamics, floc size distribution and sludge solids-liquid separation properties. Three reactor configurations were studied in bench scale activated sludge bubble column reactor (BCR), air-lift reactor (ALR) and aerated stirred reactor (ASR). The ASR demonstrated the highest capacity of gas holdup and resistance, and homogeneity in flow regimes and shearing forces, resulting in producing large numbers of small and compact floes. The fluid dynamics in the ALR created regularly directed recirculation forces to enhance the gas holdup and sludge flocculation. The BCR distributed a high turbulent flow regime and non-homogeneity in gas holdup and mixing, and generated large numbers of larger and looser floes. The sludge size distributions, compressibility and settleability were significantly influenced by the reactor configurations associated with the flow regimes and hydrodynamics.