New combined system of biological process and intermittent ozonation for advanced wastewater treatment

1998 ◽  
Vol 38 (8-9) ◽  
pp. 145-153 ◽  
Author(s):  
T. Kamiya ◽  
J. Hirotsuji
Keyword(s):  
Biological Treatment ◽  
Biological Process ◽  
Waste Water Treatment ◽  
Aeration Tank ◽  
Excess Sludge ◽  
Combined System ◽  
Remarkable Effect ◽  
Effluent Quality ◽  
Treatment Processes ◽  
Sludge Settling

A new system combining both biological treatment and intermittent ozonation has been developed to reduce excess sludge production with a small amount of ozone. In this system, activated sludge in the aeration tank was circulated via intermittent ozonation. Experimental results have shown that 50% of the sludge generation was cut down with only 30% of the ozone dose required for continuous ozonation. Furthermore, the process had a remarkable effect on maintaining the sludge settling characteristics. The sludge ozonation was almost of little influence on the effluent quality though the slight degradation of effluent quality was observed in few cases. These facts suggested the effectiveness of the newly proposed system for saving costs and stabilizing treatment performance of biological waste water treatment processes.

Minimization of sludge production in biological processes: an alternative solution for the problem of sludge disposal

2002 ◽  
Vol 46 (10) ◽  
pp. 63-70 ◽  
Author(s):  
S. Deleris ◽  
V. Geaugey ◽  
P. Camacho ◽  
H. Debellefontaine ◽  
E. Paul
Keyword(s):  
Biological Treatment ◽  
Reduction Process ◽  
Aeration Tank ◽  
Urban Wastewater ◽  
Combined System ◽  
Active Biomass ◽  
Sludge Disposal ◽  
Autotrophic Biomass ◽  
Sludge Settling ◽  
Sludge Production

A combined system associating activated sludge and ozonation was evaluated for the treatment of urban wastewater. Experiments have shown that 70% reduction in sludge production can be reached (compared to a reference system running in low loaded conditions Yobs = 0.28 g VSS.g COD-1) by applying an ozone dosage of 0.05 g O3/g VSStreated. Recycling of the ozonated sludge to the aeration tank induces a slight increase in effluent COD, but the biological treatment performance is maintained. Nitrification capabilities are not altered by the sludge reduction process and active biomass measurements revealed that autotrophic biomass seems to be less affected than the heterotrophs. Significant improvements in sludge settling characteristics are observed.

Изучение отклика дегидрогеназной активности ила на изменение технологических параметров работы аэротенка

2020 ◽  
Author(s):  
N. Zaletova ◽  
S. Zaletov
Keyword(s):  
Wastewater Treatment ◽  
Dehydrogenase Activity ◽  
Biological Treatment ◽  
Biological Process ◽  
Organic Load ◽  
Treatment Processes ◽  
Mode Of Operation ◽  
Concentrated Solution ◽  
Available Information ◽  
Complicated Mechanism

Биологический метод очистки сточных вод представляет собой сложный многокомпонентный процесс, ключевой составляющей которого является работа ферментной системы. Известно, что одним из важнейших ферментов, обеспечивающих биологический процесс, являются дегидрогеназы. Полностью сложнейший механизм действия ферментов до конца пока не раскрыт, однако в практике контроля процессов биологической очистки используется показатель дегидрогеназной активности ила. Результаты исследований позволили дополнить имеющуюся информацию фактическими данными о взаимообусловленности уровня дегидрогеназной активности ила и показателей отдельных технологических параметров биологической очистки. Показано, что режим работы аэротенков (нагрузка на ил, доза активного ила и др.) и величина показателей исходной дегидрогеназной активности и дегидрогеназной активности этого же образца ила со слабо концентрированным раствором (ДАИН2О) связаны между собой и зависят от нагрузки на ил по органическим веществам. Полученные результаты исследования могут быть использованы для контроля биологического процесса очистки сточных вод.The biological method of wastewater treatment is a comprehensive multicomponent process the activities of the enzyme system being the key component of it. It is known that dehydrogenases have been one of the most important enzymes the ensure the biological process. The complicated mechanism of the action of enzymes has not been fully described so far however, in the practice of monitoring biological treatment processes, an indicator of the dehydrogenase activity of sludge is used. The research results provided for supplementing the available information with actual data on the interdependence of the level of dehydrogenase activity of sludge and indicators of individual process parameters of biological treatment. It was shown that the mode of operation of aeration tanks (organic matter load on sludge, dose of activated sludge, etc.) and the values of the initial dehydrogenase activity and dehydrogenase activity of the same sludge sample with weakly concentrated solution (DASН2О) are interconnected and depend on the organic load on sludge. The results of the study can be used to control the biological process of wastewater treatment.The biological method of wastewater treatment is a comprehensive multicomponent process the activities of the enzyme system being the key component of it. It is known that dehydrogenases have been one of the most important enzymes the ensure the biological process. The complicated mechanism of the action of enzymes has not been fully described so far however, in the practice of monitoring biological treatment processes, an indicator of the dehydrogenase activity of sludge is used. The research results provided for supplementing the available information with actual data on the interdependence of the level of dehydrogenase activity of sludge and indicators of individual process parameters of biological treatment. It was shown that the mode of operation of aeration tanks (organic matter load on sludge, dose of activated sludge, etc.) and the values of the initial dehydrogenase activity and dehydrogenase activity of the same sludge sample with weakly concentrated solution (DASН2О) are interconnected and depend on the organic load on sludge. The results of the study can be used to control the biological process of wastewater treatment.

Two-stage chemical-biological treatment at Thessaloniki greater area WWTP - experiences and potentials

1995 ◽  
Vol 32 (9-10) ◽  
pp. 75-84 ◽  
Author(s):  
A. D. Andreadakis ◽  
G. H. Kristensen ◽  
A. Papadopoulos ◽  
C. Oikonomopoulos
Keyword(s):  
Biological Treatment ◽  
Treatment Plant ◽  
Cost Effective ◽  
Primary Treatment ◽  
Effective Control ◽  
Two Stage ◽  
Effluent Quality ◽  
Filamentous Microorganisms ◽  
Sludge Settling ◽  
The City

The wastewater from the city of Thessaloniki is discharged without treatment to the nearby inner part of the Thessaloniki Gulf. The existing, since 1989, treatment plant offers only primary treatment and did not operate since the expected effluent quality is not suitable for safe disposal to the available recipients. Upgrading of the plant for advanced biological treatment, including seasonal nitrogen removal, is due from 1995. In the mean time, after minor modifications completed in February 1992, the existing plant was put into operation as a two-stage chemical-biological treatment plant for 40 000 m3 d−1, which corresponds to about 35% of the total sewage flow. The operational results obtained during the two years operation period are presented and evaluated. All sewage and sludge treatment units of the plant perform better than expected, with the exception of the poor sludge settling characteristics, due to severe and persistent bulking caused by excessive growth of filamentous microorganisms, particularly M. Parvicella. Effective control of the bulking problem could lead to more cost-effective operation and increased influent flows.

Application of combined physicochemical and biological processes for enhanced treatment of avermectin fermentation wastewater

2009 ◽  
Vol 59 (4) ◽  
pp. 771-777 ◽  
Author(s):  
Anfeng Yu ◽  
PengYu Huang ◽  
Dawei Gui ◽  
Haisheng Wang ◽  
Quan Feng ◽  
...  
Keyword(s):  
Biological Treatment ◽  
Phosphorus Concentration ◽  
Biological Processes ◽  
Excess Sludge ◽  
Total Phosphorus Concentration ◽  
Chemical Coagulation ◽  
Treatment Processes ◽  
Dark Color ◽  
Biolog Analysis ◽  
Excess Sludge Reduction

This paper aimed at developing the enhanced biological treatment processes for treating avermectin fermentation wastewater (AFW). After UASB treatment and chemical coagulation, the pretreated AFW was subsequently flowed into a rCAA reactor (reactor with repeated coupling of aerobes and anaerobes using macroporous carriers) system for further pollutant degradation and excess sludge reduction. By the treatment with chemical coagulation, COD, total nitrogen and total phosphorus concentration of treated AFW were eliminated to 550–700 mg/L, 130–160 mg/L and 1 mg/L, respectively, and the dark color of the wastewater was greatly bleached. After this decolorized wastewater was treated by the following rCAA bioreactor, the COD could be reduced to around 200–300 mg/L, while the further decrease of COD less than 200 mg/L was difficult. The Biolog analysis and OUR test for the water treated by rCAA bioreactor demonstrated that the effluent from chemical coagulation contained some unknown compounds with low biodegradability and would simplify the microbial community in the subsequent rCAA reactor.

scholarly journals Aeration Tank Microbial Aerosols as a Factor of Water Bodies’ Pollution

2017 ◽  
Author(s):  
Keyword(s):  
Wind Velocity ◽  
Biological Treatment ◽  
Water Surface ◽  
Waste Water Treatment ◽  
Water Bodies ◽  
Aeration Tank ◽  
Waste Waters ◽  
Domestic Waste ◽  
Water Losses ◽  
Microbial Pollution

Aeration impact on aerosols discharge from aeration tanks in the process of domestic waste water treatment has been considered. Waste waters and their aerosols microbial pollution has been shown. New regularities of the temperature, time, and wind velocity on moisture discharge and microbial pollution in the form of aerosols from water surface of the biological treatment aerated facilities have been obtained. The equations that enable to calculate moisture emission from water surface in the process of aeration are presented. Water losses in the form of aerosols in the process of aeration depending on the outside air temperature and wind velocity were determined theoretically and experimentally. The microorganisms specific discharge from an aeration tank equal to 2.144 г/(m2∙s) in terms of coliform species was calculated. The microbial pollution maximal concentration values for various meteorological conditions were determined for performance of standard calculations of microbial discharges with aerosols from aeration tanks. The obtained equations can be used in designing of engineering measures aimed at reduction of the discharged aerosols negative microbial impact on water bodies adjacent to the territories of domestic waste waters biological treatment facilities.

Improving activated sludge floc structure and aggregation for enhanced settling and thickening performances

1998 ◽  
Vol 38 (8-9) ◽  
pp. 35-44 ◽  
Author(s):  
F. Clauss ◽  
D. Helaine ◽  
C. Balavoine ◽  
A. Bidault
Keyword(s):  
Activated Sludge ◽  
Fine Particles ◽  
Waste Water Treatment ◽  
Research Work ◽  
Aeration Tank ◽  
Effluent Quality ◽  
Flocculation Efficiency ◽  
Floc Structure ◽  
Liquid Phases ◽  
Insoluble Particles

The effluent quality of a sewage plant using the activated sludge process depends upon the flocculation efficiency. Intensive research work has been devoted to understanding flocculation phenomena and to correct biological disorders. The addition of very fine but dense mineral particles to the aeration tank immediately improves floc formation and increases the weight of the new flocs created. The first consequence is an effective separation between the solid and the liquid phases in the secondary clarifier. In the longer term, the fine particles improve floc structuring and form stable and strong flocs. This has been demonstrated by sending a modified activated sludge through the high shear strength of pumps and hydrocyclones. The mineral of choice is a natural blend of talc and related minerals. These fine talc particles offer a solution to solve floc settleability problems which so frequently arise when biological disorders appear in waste water treatment plants. Despite the addition of insoluble particles the amount of sludge expelled does not increase. The thickening and dewatering properties are improved.

An activated sludge process without excess sludge production

1997 ◽  
Vol 36 (11) ◽  
pp. 163-170 ◽  
Author(s):  
Yoshio Sakai ◽  
Tetsuro Fukase ◽  
Hidenari Yasui ◽  
Masahide Shibata
Keyword(s):  
Activated Sludge ◽  
Municipal Wastewater ◽  
The Other ◽  
Aeration Tank ◽  
Activated Sludge Process ◽  
Organic Substances ◽  
Complete Elimination ◽  
Excess Sludge ◽  
Effluent Quality ◽  
Inorganic Substances

An activated sludge process which produces no excess sludge was developed. The process is very simple as a small amount of return sludge is ozonated and then returned to the aeration tank. The ozonation enhances biodegradability of activated sludge, which is biologically oxidized in the aeration tank. A full-scale plant for treating 450m3/d of municipal wastewater was constructed and has been operated successfully for 9 months. The amount of excess sludge eliminated is directly proportional to the amount of ozone dosed to the sludge. At the ozone dosing rate of 0.034 kg/kg-SS, complete elimination of excess sludge has been achieved when 4 times more amount of sludge is ozonated than that of the excess sludge expected in the treatment without ozonation. After 5 months of operation without any withdrawal of excess sludge, small amount of inorganic substances like sand and silt accumulated in the sludge. On the other hand, inert organic substances does not seem to accumulate. As for effluent quality, BOD and nitrogen were kept good. Although effluent SS was 2–15 mg/l higher compared to a control without ozonation, it has been well below the discharge limit.

Feasibility study of mechanically disintegrated sludge and recycle in the activated-sludge process

2002 ◽  
Vol 46 (10) ◽  
pp. 97-104 ◽  
Author(s):  
P. Camacho ◽  
V. Geaugey ◽  
P. Ginestet ◽  
E. Paul
Keyword(s):  
Activated Sludge ◽  
Mechanical Treatment ◽  
Aeration Tank ◽  
Urban Wastewater ◽  
Combined System ◽  
Action Mechanisms ◽  
First Pass ◽  
High Pressure Homogenizer ◽  
Biological Performance ◽  
Sludge Settling

The action mechanisms and performances of a combined system associating activated sludge and mechanical treatment (High Pressure Homogenizer) were evaluated for urban wastewater. Discontinuous experiments showed that the energy applied at the first pass was high enough to modify the sludge particulate fraction (high COD release) but without cell lysis. The applied shear forces led to a progressive cell break up (maximal COD release 90% total COD). Continuous experiments showed less than 20% reduction in sludge production (compared to a control run under the same loading conditions YTSS = 0.35 g TSS.g−1CODremoved through the application of mechanical treatment (stress frequency = 0.2 d−1). Recycling of mechanical treated sludge to the aeration tank induced a slight increase in effluent TSS, but the biological performance seemed to be maintained. Significant improvements in sludge settling characteristics were observed.

scholarly journals Solar homogeneous catalysis to the removal of organic matter from slaughterhouse effluents undergone to a prior biological process

2021 ◽  
Author(s):  
J. A. Hurtado ◽  
L. F. Valdez ◽  
C. J. Escudero
Keyword(s):  
Biological Treatment ◽  
Suspended Solids ◽  
Biological Process ◽  
Renewable Energy Sources ◽  
Quality Parameters ◽  
Fenton Process ◽  
Slight Improvement ◽  
Effluent Quality ◽  
Different Types ◽  
Treatment Train

Abstract This study shows the effectiveness of the wastewater treatment from a municipal slaughterhouse undergone to a previous biological treatment applying a sequence of stages, reaching a 75% of elimination of the COD using sedimentation in combination of coagulation-flocculation, using 0.5 g/L FeCl3 which is one of the best known inorganic coagulants. Then, the elimination of COD was around 98% adding the Fenton process where 1,000 mg/L H2O2 and FeSO4 are used. In addition to the COD, other water quality parameters were measured to evaluate the level of purification of the test samples, such as solids of different types, pH, DOC and so on. With the above, it can be noted that the Fenton process had a slight improvement in the effluent quality by using a solar concentrator in the now called photo-Fenton process, reaching around 99% of COD removal (0.36 g/L), 91% of total suspended solids (0.32 g/L) and 89% of DOC (0.20 g/L). These results were the best achieved within a proposed treatment train for this type of complex wastewater. Moreover, this last part of the process adds an improvement, by the usage of renewable energy sources such as sunlight.

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