"The purpose of this investigation was to study the effects of nickel on the microbial population of activated sludge, to establish a relationship between effluent quality and changes in microbial population, and to determine the fate of nickel applied. Five one liter fill and draw activated sludge units were fed settled domestic sewage and received constant daily nickel doses of 1-10 mg/l, and a 50 mg/l slug dose applied after 27-30 days of operation. The parameters used were the chemical oxygen demand (COD) of the effluent and membrane filtered effluent, mixed liquor and effluent total suspended solids, mixed liquor volatile suspended solids, mixed liquor and effluent nickel concentrations, mixed liquor and effluent microbial counts, and mixed liquor oxygen uptake. It was found that nickel concentrations in the range of 1-10mg/l: (a) caused an increase in effluent COD resulting from the presence of a large amount of organic suspended solids; (b) increased the number of bacteria, both dead and viable, discharged in the effluent; (c) discouraged the growth of rotifers (except for the 1 mg/l dose) and free swimming ciliated protozoa and encouraged the growth of stalked protozoa. About one-half of the nickel introduced was lost in the effluent, while considerably more was released following the addition of a slug dose; this could account for the recovery of activated sludge from slug doses. The absence of free swimming protozoa appeared to be responsible for the deterioration of the effluent"--Abstract, page [i].
Grigoropoulos, Sotirios G.
Wixson, Bobby G.
Siehr, Donald J.
Wulfman, David S., 1934-2013
Civil, Architectural and Environmental Engineering
M.S. in Civil Engineering
United States. Federal Water Pollution Control Administration
University of Missouri at Rolla
iv, 103 pages
© 1967 Virgil Eugene Carr, All rights reserved.
Thesis - Open Access
Nickel -- Environmental aspects
Sewage -- Purification -- Activated sludge process
Print OCLC #
Electronic OCLC #
Link to Catalog Record
Carr, Virgil Eugene, "Some effects of nickel on the microbial population of activated sludge" (1967). Masters Theses. 5165.