Determination of the impact of toxic inflows on the performance of activated sludge by wastewater characterization

1997 ◽  
Vol 36 (2-3) ◽  
pp. 45-52 ◽  
Author(s):  
A. D. Andreadakis ◽  
C. M. Kalergis ◽  
N. Kartsonas ◽  
D. Anagnostopoulos

A rational approach for the design of the activated sludge process based on wastewater and biomass characterization techniques as applied to the upgrading of the treatment plant of Volos, a city in the central part of Greece, is presented. The study investigates possible nitrification inhibition and carbon inadequacy, due to high salinity, industrial inflows and pre-precipitation by iron salts. The experimentation was carried out by means of batch Ammonium Uptake Rate (AUR) and Nitrates Uptake Rate (NUR) tests. The results show that within the studied range, 900-4000 mg l−1, chlorides did not inhibit nitrification. Contrary to this, the industrial wastewater entering the plant was found to be toxic. With the existing 1:15 ratio of industrial to total wastewater flow a 50% inhibition to the nitrification process was observed, which is higher than the 25 - 30% inhibition caused by typical domestic sewage. Industrial contributions exceeding 20% resulted in complete inhibition of nitrification. With respect to denitrification it was found that the industrial wastewater provided a suitable source of carbon, without any adverse effects on denitrification. Pre-precipitation removed about 25% of the filtered COD, thus reducing the amount of nitrates which could be rapidly denitrified. Design of the biological reactors on the basis of the findings indicate that a significant under-design may result if typical nitrification and denitrification rates obtained from the literature and practice concerning typical domestic sewage are adopted.

1988 ◽  
Vol 20 (11-12) ◽  
pp. 131-136 ◽  
Author(s):  
A. D. Wong ◽  
C. D. Goldsmith

The effect of discharging specific oil degrading bacteria from a chemostat to a refinery activated sludge process was determined biokinetically. Plant data for the kinetic evaluation of the waste treatment plant was collected before and during treatment. During treatment, the 500 gallon chemostatic growth chamber was operated on an eight hour hydraulic retention time, at a neutral pH, and was fed a mixture of refinery wastewater and simple sugars. The biokinetic constants k (days−1), Ks (mg/L), and K (L/mg-day) were determined before and after treatment by Monod and Lineweaver-Burk plots. Solids discharged and effluent organic concentrations were also evaluated against the mean cell retention time (MCRT). The maximum utilization rate, k, was found to increase from 0.47 to 0.95 days−1 during the operation of the chemostat. Subsequently, Ks increased from 141 to 556 mg/L. Effluent solids were shown to increase slightly with treatment. However, this was acceptable due to the polishing pond and the benefit of increased ability to accept shock loads of oily wastewater. The reason for the increased suspended solids in the effluent was most likely due to the continual addition of bacteria in exponential growth that were capable of responding to excess substrate. The effect of the chemostatic addition of specific microbial inocula to the refinery waste treatment plant has been to improve the overall organic removal capacity along with subsequent gains in plant stability.


1997 ◽  
Vol 36 (2-3) ◽  
pp. 1-8 ◽  
Author(s):  
P. Grau ◽  
B. P. Da-Rin

An unusually severe case of toxicity accompanied by activated sludge filamentous bulking was observed at the wastewater treatment plant Sao Paulo-Barueri. Treatment efficiency of the plant, operated without major problems for more than five years before, was significantly hindered for almost six months. Occurrence of toxic shocks was confirmed partly directly but mostly indirectly by inhibition of nitrification and biological phenomena related to toxicity. Several measures adopted, including the recycled activated sludge chlorination, are described in the paper.


Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2657
Author(s):  
Elwira Nowobilska-Majewska ◽  
Piotr Bugajski

The aim of this study was to determine the condition of activated sludge in the biologic reactor located in the collective wastewater treatment plant in Nowy Targ (Poland) based on OUR tests in the aspect of the impact of sludge’s concentration in the biologic reactor and dependence of BOD5/TN and BOD5/TP in wastewater flowing into the biologic reactor. The analysis was conducted based on test results from 61 samples of activated sludge taken from the biologic reactor and 61 samples of wastewater flowing into the biologic reactor. The analysis included the concentration of sludge in the biologic reactor. The following indicators were analyzed in wastewater flowing into the reactor: biochemical oxygen demand (BOD5), total nitrogen (TN) and total phosphorus (TP). The statistical analysis concerning the impact of the analyzed factors on oxygen uptake rate (OUR) tests was developed based on the Pearson’s correlation coefficient and partial correlation of many variables. Based on the results of the partial correlation analysis, nomograms were developed to determine the condition of activated sludge microorganisms (OUR) based on the BOD5/TN and BOD5/TP connection and knowledge of the sludge concentration in the bioreactor of the treatment plant. The presented nomograms can be formulated for each bioreactor based on activated sludge technology related the load of organic and biogenic pollutants in the wastewater flowing into the bioreactor and the concentration of the sludge in the bioreactor.


1999 ◽  
Vol 40 (1) ◽  
pp. 275-279 ◽  
Author(s):  
G. (Goktayoglu) Demirbas ◽  
C. F. Gokcay ◽  
F. B. Dilek

A model activated sludge (AS) plant was fed by pulping effluents from a straw and reed processing paper works. The model was initially operated to simulate a dedicated treatment plant by continuously receiving chlorinated effluents from the pulp bleachery. In this simulation cycle the model activated sludge was seeded only once during start-up and did not receive any domestic sewage after that. A carbon source was added in some of the experiments to bring up the organic content. In the second simulation cycle the pulping effluent was co-treated with municipal sewage. In this case the activated sludge unit was being continuously dosed by microorganisms and the organics present in the sewage. A higher organic chlorine (AOX) removal was obtained at shorter SRTs in the co-treatment AS. High AOX removal was achieved at longer SRTs in the dedicated, once-seeded AS. The AOX removal mechanism was mineralization in both cycles.


1988 ◽  
Vol 20 (10) ◽  
pp. 201-210 ◽  
Author(s):  
S. Matsui ◽  
Y. Okawa ◽  
R. Ota

Twenty-eight process wastewaters and thirty-seven organic substances identified in the wastewater of the Kashima petrochemical complex were subjected to biodegradability tests. The tests consisted of the activated sludge degradability method and a supplementary test using the respiration meter method. Both tests utilized the activated sludge of the Fukashiba industrial wastewater treatment plant, which was acclimatized to the wastewater and organic substances. The 28 process wastewaters were classified into biodegradable, less biodegradable, and non-biodegradable according to the percentage TOC removal and the BOD5/TOC ratio of the wastewater. The 37 organic substances were also classified into biodegradable, less biodegradable and non-biodegradable according to TOC and CODMn removal. In general, chlorinated compounds, nitro-aromatics and polymerized compounds were difficult to biodegrade. From the biodegradability tests of the factory wastewaters, it was found that the refractory CODMn loads of these factories contributed to the load remaining in the effluent of the wastewater treatment plant. Various improvements were made to reduce the discharge of refractory substances from the factories.


1996 ◽  
Vol 33 (6) ◽  
pp. 101-107 ◽  
Author(s):  
Robert W. Okey ◽  
H. David Stensel ◽  
Mary C. Martis

A quantitative structure-activity relationship (QSAR)-type model using groups and molecular connectivity has been developed on nitrification inhibition data derived from soil. The model has been tested against data derived from the inhibition of nitrification by specific nitrogen-containing pesticides. A second QSAR-type model developed from acclimated biodegradation data has been applied to the pesticides tested for nitrification inhibition. Data on the impact of specific compounds on activated sludge nitrification have been included and the soil model applied to these activated sludge data. In general, the agreement between predicted and observed values for nitrification inhibition was satisfactory. The agreement was only marginal with respect to the biological system data. The biodegradation model indicated that most of the strong inhibitors also would have prolonged existence in the open environment. The models are included in the paper as well as the specific methodology.


2000 ◽  
Vol 66 (3) ◽  
pp. 1167-1174 ◽  
Author(s):  
A. C. Layton ◽  
P. N. Karanth ◽  
C. A. Lajoie ◽  
A. J. Meyers ◽  
I. R. Gregory ◽  
...  

ABSTRACT The bacterial community structure of the activated sludge from a 25 million-gal-per-day industrial wastewater treatment plant was investigated using rRNA analysis. 16S ribosomal DNA (rDNA) libraries were created from three sludge samples taken on different dates. Partial rRNA gene sequences were obtained for 46 rDNA clones, and nearly complete 16S rRNA sequences were obtained for 18 clones. Seventeen of these clones were members of the beta subdivision, and their sequences showed high homology to sequences of known bacterial species as well as published 16S rDNA sequences from other activated sludge sources. Sixteen clones belonged to the alpha subdivision, 7 of which showed similarity to Hyphomicrobium species. This cluster was chosen for further studies due to earlier work onHyphomicrobium sp. strain M3 isolated from this treatment plant. A nearly full-length 16S rDNA sequence was obtained fromHyphomicrobium sp. strain M3. Phylogenetic analysis revealed that Hyphomicrobium sp. strain M3 was 99% similar to Hyphomicrobium denitrificans DSM 1869T inHyphomicrobium cluster II. Three of the cloned sequences from the activated sludge samples also grouped with those ofHyphomicrobium cluster II, with a 96% sequence similarity to that of Hyphomicrobium sp. strain M3. The other four cloned sequences from the activated sludge sample were more closely related to those of the Hyphomicrobium cluster I organisms (95 to 97% similarity). Whole-cell fluorescence hybridization of microorganisms in the activated sludge with genus-specificHyphomicrobium probe S-G-Hypho-1241-a-A-19 enhanced the visualization of Hyphomicrobium and revealed thatHyphomicrobium appears to be abundant both on the outside of flocs and within the floc structure. Dot blot hybridization of activated sludge samples from 1995 with probes designed forHyphomicrobium cluster I and Hyphomicrobiumcluster II indicated that Hyphomicrobium cluster II-positive 16S rRNA dominated over Hyphomicrobium cluster I-positive 16S rRNA by 3- to 12-fold. Hyphomicrobium 16S rRNA comprised approximately 5% of the 16S rRNA in the activated sludge.


2016 ◽  
Vol 42 (1) ◽  
pp. 27-34 ◽  
Author(s):  
Anna Gnida ◽  
Jarosław Wiszniowski ◽  
Ewa Felis ◽  
Jan Sikora ◽  
Joanna Surmacz-Górska ◽  
...  

AbstractThe paper deals with the problem of the determination of the effects of temperature on the efficiency of the nitrification process of industrial wastewater, as well as its toxicity to the test organisms. The study on nitrification efficiency was performed using wastewater from one of Polish chemical factories. The chemical factory produces nitrogen fertilizers and various chemicals. The investigated wastewater was taken from the influent to the industrial mechanical-biological wastewater treatment plant (WWTP). The WWTP guaranteed high removal efficiency of organic compounds defined as chemical oxygen demand (COD) but periodical failure of nitrification performance was noted in last years of the WWTP operation. The research aim was to establish the cause of recurring failures of nitrification process in the above mentioned WWTP. The tested wastewater was not acutely toxic to activated sludge microorganisms. However, the wastewater was genotoxic to activated sludge microorganisms and the genotoxicity was greater in winter than in spring time. Analysis of almost 3 years’ period of the WWTP operation data and laboratory batch tests showed that activated sludge from the WWTP under study is very sensitive to temperature changes and the nitrification efficiency collapses rapidly under 16°C. Additionally, it was calculated that in order to provide the stable nitrification, in winter period the sludge age (SRT) in the WWTP should be higher than 35 days.


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