Extended statistical entropy analysis (eSEA) for improving the evaluation of Austrian wastewater treatment plants

2013 ◽  
Vol 67 (5) ◽  
pp. 1051-1057 ◽  
Author(s):  
A. Sobańtka ◽  
H. Rechberger
Keyword(s):  
Wastewater Treatment ◽  
Cost Efficiency ◽  
Biological Treatment ◽  
Wastewater Treatment Plants ◽  
Removal Rate ◽  
Entropy Analysis ◽  
Statistical Entropy ◽  
N Removal ◽  
Cost Efficient ◽  
Biological Treatment Process

Extended statistical entropy analysis (eSEA) is used to evaluate the nitrogen (N) budgets of 13 Austrian wastewater treatment plants (WWTPs). The eSEA results are then compared to the WWTPs specific N-removal rates. Among the five WWTPs that achieve a removal rate of 75% the eSEA detects significant differences in the N-performance. The main reason for this is that eSEA considers all N-species and seems to be more discriminating than the N-removal rate. Additionally, the energy consumption and the costs of the mechanical–biological treatment process are related to the N-performance according to the eSEA. The influence of the WWTP size on the energy- and cost-efficiency of the N-treatment is investigated. Results indicate that energy-efficiency does not necessarily coincide with cost-efficiency. It is shown that smaller WWTPs between 22,000 PE (population equivalents) and 50,000 PE can be operated as energy-efficiently as larger WWTPs between 100,000 and 1,000,000 PE. On average, the smaller plants operate less cost-efficiently than the large ones. This research offers a new method for the assessment of the N-performance of WWTPs, and suggests that small WWTPs are not necessarily less energy- and cost-efficient than large ones.

Evaluation of Small Wastewater Treatment Plants in the County of Århus – Denmark

1993 ◽  
Vol 28 (10) ◽  
pp. 33-41
Author(s):  
Jes la Cour Jansen ◽  
Bodil Mose Pedersen ◽  
Erik Moldt
Keyword(s):  
Wastewater Treatment ◽  
Constructed Wetlands ◽  
Biological Treatment ◽  
Wastewater Treatment Plants ◽  
Chemical Precipitation ◽  
Common Type ◽  
Treatment Efficiency ◽  
Effluent Quality ◽  
Different Types

Influent and effluent data from about 120 small wastewater treatment plants (100 - 2000 PE) have been collected and processed. Seven different types of plants are represented. The effluent quality and the treatment efficiency have been evaluated. The most common type of plant is mechanical/biological treatment plants. Some of them are nitrifying and some are also extended for chemical precipitation of phosphorus. Constructed wetlands and biological sandfilters are also represented among the small wastewater treatment plants.

Use of modelling for optimization and upgrade of a tropical wastewater treatment plant in a developing country

2007 ◽  
Vol 56 (7) ◽  
pp. 21-31 ◽  
Author(s):  
D. Brdjanovic ◽  
M. Mithaiwala ◽  
M.S. Moussa ◽  
G. Amy ◽  
M.C.M. van Loosdrecht
Keyword(s):  
Wastewater Treatment ◽  
Developing Country ◽  
Wastewater Treatment Plant ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Coupled Model ◽  
Reject Water ◽  
Complex Interactions ◽  
N Removal ◽  
Discharge Criteria

This paper presents results of a novel application of coupling the Activated Sludge Model No. 3 (ASM3) and the Anaerobic Digestion Model No.1 (ADM1) to assess a tropical wastewater treatment plant in a developing country (Surat, India). In general, the coupled model was very capable of predicting current plant operation. The model proved to be a useful tool in investigating various scenarios for optimising treatment performance under present conditions and examination of upgrade options to meet stricter and upcoming effluent discharge criteria regarding N removal. It appears that use of plant-wide modelling of wastewater treatment plants is a promising approach towards addressing often complex interactions within the plant itself. It can also create an enabling environment for the implementations of the novel side processes for treatment of nutrient-rich, side-streams (reject water) from sludge treatment.

Computational intelligence-based optimisation of wastewater treatment plants

2005 ◽  
Vol 52 (12) ◽  
pp. 99-104 ◽  
Author(s):  
M. Bongards ◽  
T. Hilmer ◽  
A. Ebel
Keyword(s):  
Wastewater Treatment ◽  
Computational Intelligence ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Municipal Wastewater Treatment ◽  
Peak Loads ◽  
The Government ◽  
Cost Efficient ◽  
Municipal Wastewater Treatment Plants ◽  
Classical Control

Methods of computational intelligence (CI), especially fuzzy control and neuronal networks, are used for controlling and optimising of wastewater treatment plants. Areas of application are the control of sludge water dosage, of phosphate elimination by optimal precipitant dosage as well as an optimal aeration in the nitrification zone. In two municipal wastewater treatment plants with 60,000 and 12,600 person equivalents the controllers have been installed and optimised and they have been in operation for several years. Results of operation of the plants are presented in comparison to previously used classical control. Performance increased significantly and the outflow values could be kept securely below the government requirements without increase of the energy consumption. Peak loads in the inflow were eliminated in the plant and did not increase outflow concentrations. Results of operation for more than three years clearly show that the CI controller is a cost-efficient method for a sustainable rise of performance in municipal wastewater treatment plants.

scholarly journals Combined Application of UV Photolysis and Ozonation with Biological Aerating Filter in Tertiary Wastewater Treatment

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Zhaoqian Jing ◽  
Shiwei Cao
Keyword(s):  
Molecular Weight ◽  
Wastewater Treatment ◽  
Organic Pollutants ◽  
Wastewater Treatment Plants ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Cod Removal ◽  
Secondary Effluent ◽  
Uv Photolysis ◽  
Combined Application

To enhance the biodegradability of residual organic pollutants in secondary effluent of wastewater treatment plants, UV photolysis and ozonation were used in combination as pretreatment before a biological aerating filter (BAF). The results indicated that UV photolysis could not remove much COD (chemical oxygen demand), and the performance of ozonation was better than the former. With UV photolysis combined with ozonation (UV/O3), COD removal was much higher than the sum of that with UV photolysis and ozonation alone, which indicated that UV photolysis could efficiently promote COD removal during ozonation. This pretreatment also improved molecular weight distribution (MWD) and biodegradability greatly. Proportion of organic compounds with molecular weight (MW) <3 kDalton was increased from 51.9% to 85.9%. COD removal rates with BAF and O3/BAF were only about 25% and 38%, respectively. When UV/O3oxidation was combined with BAF, the average COD removal rate reached above 61%, which was about 2.5 times of that with BAF alone. With influent COD ranging from 65 to 84 mg/L, the effluent COD was stably in the scope of 23–31 mg/L. The combination of UV/O3oxidation with BAF was quite efficient in organic pollutants removal for tertiary wastewater treatment.

scholarly journals Global Internal Recirculation Alternative Operation to Reduce Nitrogen and Ammonia Limit Violations and Pumping Energy Costs in Wastewater Treatment Plants

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1606
Author(s):  
Ignacio Santín ◽  
Ramon Vilanova ◽  
Carles Pedret ◽  
Marian Barbu
Keyword(s):  
Wastewater Treatment ◽  
Flow Rate ◽  
Biological Treatment ◽  
Fuzzy Controller ◽  
Wastewater Treatment Plants ◽  
Nitrate Concentration ◽  
Great Influence ◽  
Energy Costs ◽  
Recirculation Flow ◽  
Operational Costs

The internal recirculation plays an important role in different areas of the biological treatment of wastewater treatment plants because it has a great influence on the concentration of pollutants, especially nutrients. A usual manipulation of the internal recirculation flow rate is based on the target of controlling the nitrate concentration in the last anoxic tank. This work proposes an alternative for the manipulation of the internal recirculation flow rate instead of nitrate control, with the objective of avoiding limit violations of nitrogen and ammonia concentrations and reducing operational costs. A fuzzy controller is proposed to achieve it based on the effects of the internal recirculation flow rate in different areas of the biological treatment. The proposed manipulation of the internal recirculation flow rate is compared to the application of the usual nitrate control in an already established and published operation strategy by using the internationally known benchmark simulation model no. 2 as a working scenario. The results show improvements with reductions of 59.40% in ammonia limit violations, 2.35% in total nitrogen limit violations, and 38% in pumping energy costs.

Performance of activated sludge diffusion for biological treatment of hydrogen sulphide gas emissions

2013 ◽  
Vol 68 (9) ◽  
pp. 1932-1939 ◽  
Author(s):  
Vera L. Barbosa ◽  
Richard M. Stuetz
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Hydrogen Sulphide ◽  
Biological Treatment ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Broad Application ◽  
H2s Removal ◽  
Treatment Performance ◽  
Solids Concentration

Odours from wastewater treatment plants are comprised of a mixture of various gases with hydrogen sulphide (H2S) often being the dominant constituent. Activated sludge diffusion (ASD) as a biotreatment system for odour abatement has been conducted for over 30 years but has limited broad application due to disagreement in the literature regarding the effect that ASD may have on wastewater treatment performance. The effects of continuous H2S diffusion at 25 ppmv, with weekly peaks of approximately 100 ppmv, on H2S removal efficiency and wastewater treatment performance was evaluated over a 2-month period using an activated sludge pilot plant. H2S removal averaged 100% during diffusion at 25 ppmv, and 98.9% during the 100 ppmv peak periods. A significant increase in mixed liquor volatile suspended solids concentration (P &lt; 0.01) was observed during H2S diffusion, which may be due to an increase in H2S-degrading microorganisms. There was no adverse effect of H2S on nitrification throughout the ASD trials. Ammonia (NH3) removal was slightly better in the test receiving H2S diffusion (87.6%) than in the control (85.4%). H2S diffusion appeared to improve robustness of the AS biomass to operational upsets.

Characteristics of estrogen decomposition by ozonation

2006 ◽  
Vol 54 (10) ◽  
pp. 87-93 ◽  
Author(s):  
T. Hashimoto ◽  
K. Takahashi ◽  
T. Murakami
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Estrogenic Activity ◽  
Removal Rate ◽  
Treatment Plant ◽  
Treated Wastewater ◽  
Ozone Dose ◽  
Natural Estrogens ◽  
Ethynyl Estradiol ◽  
Estrogen Concentration

Since the natural estrogens 17 β-estradiol (E2) and estron (E1), and the synthetic estrogen 17 α-ethynyl estradiol (EE2) have strong endocrine disrupting effects and the tendency to persist in effluent from wastewater treatment plants, effective measures are needed to remove them from wastewater. In this research, to gain an understanding of the characteristics of estrogen decomposition by ozonation, experiments were conducted using effluent from an actual wastewater treatment plant. In this experiment, estrogen was added to effluent at a concentration of 200 ng/l and 20 ng/l before the ozonation experiments. The results showed 90% or more of estrogen concentration and estrogenic activity of E2, E1 and EE2 to be removed at an ozone dose of 1 mg/l. At an ozone dose of 3 mg/l, the estrogen concentration and estrogenic activity of E2, E1 and EE2 in the treated water fell below the detection limit. The removal rate was not influenced by the kind of estrogen. No generation of byproducts with estrogenic activity was observed. The authors conclude that estrogen in secondary treated wastewater can be almost entirely removed at the practical ozone dose rate applied for the purpose of disinfection, which is up to about 5 mg/l.

Investigation of a Full-Scale Anaerobic-Aerobic and Constructed Wetlands Integrated System Treating Livestock Wastewater

2010 ◽  
Vol 113-116 ◽  
pp. 1189-1194
Author(s):  
Yong Ming Wu ◽  
Jin Bao Wan ◽  
Ji Hai Xiong ◽  
Shun Fa Wang ◽  
Ping Gu
Keyword(s):  
Constructed Wetlands ◽  
Biological Treatment ◽  
Large Scale ◽  
Wastewater Treatment Plants ◽  
Removal Rate ◽  
Full Scale ◽  
Integrated System ◽  
Tertiary Treatment ◽  
Livestock Wastewater ◽  
Aerobic Process

A full-scale integrated system of the IOC-SBBR and CWs for the biological treatment of livestock wastewater was carried out in this study, the combined IOC-SBBR process had the removal rates of COD, NH4+-N, TN reached 96.5%, 89% and 81.1%, respectively. CWs were used for the further tertiary treatment of livestock wastewater, which the average removal rate of the NH4+-N and TN was 61.3% and 60.2%, the overall integrated system was superior to the direct anaerobic or aerobic process for the treatment of large-scale livestock wastewater, would provide the valuable design and operation for the livestock wastewater treatment plants.

Granular activated algae for wastewater treatment

2015 ◽  
Vol 71 (6) ◽  
pp. 832-839 ◽  
Author(s):  
O. Tiron ◽  
C. Bumbac ◽  
I. V. Patroescu ◽  
V. R. Badescu ◽  
C. Postolache
Keyword(s):  
Wastewater Treatment ◽  
Removal Efficiency ◽  
Removal Rate ◽  
Oxygen Demand ◽  
Transformation Rate ◽  
Batch Mode ◽  
Promising Alternative ◽  
Ph Variation ◽  
Microalgae Harvesting ◽  
Cost Efficient

The study used activated algae granules for low-strength wastewater treatment in sequential batch mode. Each treatment cycle was conducted within 24 h in a bioreactor exposed to 235 μmol/m2/s light intensity. Wastewater treatment was performed mostly in aerobic conditions, oxygen being provided by microalgae. High removal efficiency of chemical oxygen demand (COD) was achieved (86–98%) in the first hours of the reaction phase, during which the indicator's removal rate was 17.4 ± 3.9 mg O2/g h; NH4+ was removed during organic matter degradation processes with a rate of 1.8 ± 0.6 mg/g h. After almost complete COD removal, the NH4+ remaining in the liquor was removed through nitrification processes promoted by the increase of the liquor's oxygen saturation (O2%), the transformation rate of NH4+ into NO3− increasing from 0.14 ± 0.05 to 1.5 ± 0.4 mg NH4+/g h, along with an O2% increase. A wide removal efficiency was achieved in the case of PO43– (11–85%), with the indicator's removal rate being 1.3 ± 0.7 mg/g h. In the provided optimum conditions, the occurrence of the denitrifying activity was also noticed. A large pH variation was registered (5–8.5) during treatment cycles. The granular activated algae system proved to be a promising alternative for wastewater treatment as it also sustains cost-efficient microalgae harvesting, with microalgae recovery efficiency ranging between 99.85 and 99.99% after granules settling with a velocity of 19 ± 3.6 m/h.

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