Effects of fluoride, boron, arsenic and thiocyanate on ammonia and thiocyanate oxidation in extended aeration activated sludge process

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1985

OSTI ID:5604926

Whang, G D

The objective of the study is the investigation of the synergistic and/or antagonistic effects of potentially inhibitory chemicals (fluoride, boron and arsenic) on the biological oxidation of ammonia and thiocyanate by the activated sludge process, and the evaluation of the concentrations at which inhibition is observed. These chemicals frequently are found in coal gasification wastewaters. An ammonia feed (400 mg/l) was used to develop nitrifying activated sludge and a second feed containing 400 mg/l of ammonia and 200 mg/l of thiocyanate was used to develop organisms which could treat typical coal gasification wastewaters which are low in organic carbon content. Batch experiments were conducted to evaluate the effects of various concentrations of thiocyanate, fluoride, boron and arsenic and to estimate the threshold concentrations and the degree of inhibition caused by each compound or anion. A biological population acclimated to both ammonia and thiocyanate was able to completely oxidize 400 mg/l ammonia and 200 mg/l thiocyanate in a synthetic coal gasification wastewater at an one-day hydraulic detention time. The ammonia nitrogen and thiocyanate concentrations in the effluent were consistently less than 1 mg/l and 0.5 g/l, respectively. The threshold concentrations of thiocyanate, fluoride, boron and arsenic before inhibition of biological nitrification and thiocyanate oxidation was observed are relatively high. Complete oxidation of 1000 mg/l thiocyanate and 400 mg/l ammonia were observed in the presence of 300 mg/l fluoride, 300 mg/l boron and 300 mg/l arsenic. However, although the substrate removal efficiency was not affected, the effluent suspended solids concentration increased to 80 mg/l.

• Research Organization: Texas Univ., Austin (USA)
• OSTI ID: 5604926
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010800* -- Coal
Lignite
& Peat-- Waste Management
ACTIVATED SLUDGE PROCESS
AMMONIA
ANTITHYROID DRUGS
ARSENIC
BENCH-SCALE EXPERIMENTS
BIOLOGICAL EFFECTS
BORON
CARBONIC ACID DERIVATIVES
CHEMICAL REACTIONS
COAL GASIFICATION PLANTS
DRUGS
ELEMENTS
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HORMONE ANTAGONISTS
HYDRIDES
HYDROGEN COMPOUNDS
INDUSTRIAL PLANTS
INHIBITION
LIQUID WASTES
MANAGEMENT
MICROORGANISMS
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXIDATION
OXYGEN COMPOUNDS
PROCESSING
QUANTITY RATIO
SEMIMETALS
THIOCYANATES
WASTE MANAGEMENT
WASTE PROCESSING
WASTE WATER
WASTES
WATER
WATER TREATMENT