Heavy-metal toxicity phenomena in laboratory-scale ANFLOW bioreactors

Technical Report · Thu Apr 01 00:00:00 EST 1982

DOI:https://doi.org/10.2172/5287986· OSTI ID:5287986

Rivera, A. L.

An energy-conserving wastewater treatment system was developed based on an anaerobic, upflow (ANFLOW) bioreactor. Since many applications of the ANFLOW process could involve the treatment of wastewaters containing heavy metals, the potentially toxic effects of these metals on the biological processes occurring in ANFLOW columns (primarily acetogenesis and methanogenesis) were investigated. Both step and pulse inputs of zinc ranging from 100 to 1000 mg/L were added to synthetic wastewaters being treated in ANFLOW columns with 0.057-m/sup 3/ volumes. Column responses were used to develop descriptive models for toxicity phenomena in such systems. It was found that an inhibition function could be defined and used to modify a model based on plugflow with axial dispersion and first-order kinetics for soluble substrate removal. The inhibitory effects of zinc on soluble substrate removal were found to be predominantly associated with its sorption by biosolids. Sorption initially occurred in the lower regions of the column, but was gradually observed in higher regions as the sorption capacity of the lower regions was exhausted. Sorption phenomena could be described with the Freundlich equation. Sorption processes were accompanied by shifts of biological processes to regions higher in the columns. A regenerative process was observed when feeding of wastewaters without zinc was resumed. It was postulated that regeneration could be based on sloughing of layers of biofilms, or other biosolids involved in zinc sorption, followed by continued growth of lower layers of biofilms not involved in heavy-metal sorption.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5287986
• Report Number(s): ORNL/TM-7837; ON: DE82013249
• Resource Relation: Other Information: Portions of document are illegible. Thesis. Submitted to the Northwestern Univ., Chicago, IL
• Country of Publication: United States
• Language: English

Related Subjects

09 BIOMASS FUELS
METALS
TOXICITY
WASTE PROCESSING PLANTS
WASTE WATER
ANAEROBIC DIGESTION
CHEMICAL COMPOSITION
CHEMICAL OXYGEN DEMAND
CHEMICAL REACTORS
METHANOGENIC BACTERIA
PH VALUE
WATER TREATMENT PLANTS
ZINC
BACTERIA
BIOCONVERSION
DIGESTION
ELEMENTS
HYDROGEN COMPOUNDS
INDUSTRIAL PLANTS
LIQUID WASTES
MANAGEMENT
MICROORGANISMS
OXYGEN COMPOUNDS
PROCESSING
WASTE MANAGEMENT
WASTE PROCESSING
WASTES
WATER
140504* - Solar Energy Conversion- Biomass Production & Conversion- (-1989)
090122 - Hydrocarbon Fuels- Preparation from Wastes or Biomass- (1976-1989)