Aerobic biological treatment of thermophilically digested sludge

2011 ◽  
Vol 63 (10) ◽  
pp. 2340-2345 ◽  
Author(s):  
M. V. Kevbrina ◽  
Y. A. Nikolaev ◽  
D. A. Danilovich ◽  
A. Ya. Vanyushina
Keyword(s):  
Retention Time ◽  
Biological Treatment ◽  
Hydraulic Retention Time ◽  
Treatment Plant ◽  
Ammonium Nitrogen ◽  
Wastewater Sludge ◽  
Optimal Conditions ◽  
Nitrogen And Phosphorus ◽  
Digested Sludge ◽  
Sludge Treatment

Aerobic biological treatment of digested sludge was studied in a continuously operated laboratory set-up. An aerated reactor was filled with thermophilically digested sludge from the Moscow wastewater treatment plant and inoculated with special activated sludge. It was then operated at the chemostat mode at different flow rates. Processes of nitrification and denitrification, as well as dephosphatation, occurred simultaneously during biological aerobic treatment of thermophilically digested sludge. Under optimal conditions, organic matter degradation was 9.6%, the concentrations of ammonium nitrogen and phosphate decreased by 89 and 83%, respectively, while COD decreased by 12%. Dewaterability of digested sludge improved significantly. The processes were found to depend on hydraulic retention time, oxygen regime, and temperature. The optimal conditions were as follows: hydraulic retention time 3–4 days, temperature 30–35 °C, dissolved oxygen levels 0.2–0.5 mg/L at continuous aeration or 0.7–1 mg/L at intermittent aeration. Based on these findings, we propose a new combined technology of wastewater sludge treatment. The technology combines two stages: anaerobic digestion followed by aerobic biological treatment of digested sludge. The proposed technology makes it possible to degrade the sludge with conversion of ∼45% volatile suspended solids to biogas, to improve nitrogen and phosphorus removal in reject water from sludge treatment units, and to achieve removal of malodorous substances after 8–9 days of anaerobic–aerobic sludge treatment.

Anaerobic thermophilic digestion of sewage sludge with a thickened sludge recycle

2012 ◽  
Vol 65 (3) ◽  
pp. 403-409 ◽  
Author(s):  
A. Ya. Vanyushina ◽  
Yu. A. Nikolaev ◽  
A. M. Agarev ◽  
M. V. Kevbrina ◽  
M. N. Kozlov
Keyword(s):  
Retention Time ◽  
Municipal Wastewater ◽  
Hydraulic Retention Time ◽  
Biogas Production ◽  
Wastewater Sludge ◽  
Recycling Process ◽  
Digested Sludge ◽  
Volatile Solids ◽  
Solids Retention ◽  
Thermophilic Digestion

The process of anaerobic thermophilic digestion of municipal wastewater sludge with a recycled part of thickened digested sludge, was studied in semi-continuous laboratory digesters. This modified recycling process resulted in increased solids retention time (SRT) with the same hydraulic retention time (HRT) as compared with traditional digestion without recycling. Increased SRT without increasing of HRT resulted in the enhancement of volatile substance reduction by up to 68% in the reactor with the recycling process compared with 34% in a control conventional reactor. Biogas production was intensified from 0.3 L/g of influent volatile solids (VS) in the control reactor up to 0.35 L/g VS. In addition, the recycling process improved the dewatering properties of digested sludge.

Simultaneous removal of nitrogen and phosphorus in a two-biofilter system

2000 ◽  
Vol 41 (12) ◽  
pp. 101-106 ◽  
Author(s):  
D. Pak ◽  
W. Chang
Keyword(s):  
Retention Time ◽  
Phosphorus Removal ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Aerobic Condition ◽  
Nitrogen Loading ◽  
Simultaneous Removal ◽  
Nitrogen And Phosphorus ◽  
Nitrogen And Phosphorus Removal ◽  
Factors Affecting

A two-biofilter system operated under alternate conditions of anaerobic/aerobic was tested to simultaneously remove nitrogen and phosphorus from sewage. The factors affecting simultaneous removal of nitrogen and phosphorus by the two-biofilter system were investigated. Those factors appeared to be influent COD/T-N and COD/T-P ratio, nitrogen loading rate and hydraulic retention time. Nitrite and nitrate produced in the biofilter in aerobic condition affected phosphorus removal by the two-biofilter system. The amount of biomass wasted during the backwash procedure also affected total nitrogen and phosphorus removal by the system.

Destruction of Faecal Bacteria, Enteroviruses and OVA of Parasites in Wastewater Sludge by Aerobic Thermophilic and Anaerobic Mesophilic Digestion

1991 ◽  
Vol 24 (2) ◽  
pp. 377-380 ◽  
Author(s):  
E. G. Carrington ◽  
E. B. Pike ◽  
D. Auty ◽  
R. Morris
Keyword(s):  
Sewage Treatment ◽  
Treatment Plant ◽  
Wastewater Sludge ◽  
Sludge Treatment ◽  
Volatile Solids ◽  
Working Volume ◽  
Thermotolerant Coliforms ◽  
Mesophilic Digestion ◽  
Faecal Bacteria ◽  
Faecal Streptococci

A new sludge treatment plant at Harrogate South Sewage Treatment Works is designed to handle up to 4 tonnes (dry solids) daily. Sludge is thickened continuously up to 8% (ds) and is then treated in parallel anaerobic mesophilic (AD) and thermophilic aerobic digestion (TAD) plants each with a maximum working volume of 530m3. Microbiological studies were carried out to compare the destruction of pathogens and faecal indicator bacteria. The AD plant operated with a mean retention of 26 days at 34 °C and achieved 49% reduction of volatile solids. The TAD plant operated with a mean retention of 28 days at 55 °C and reduced volatile solids by 35%. Operation was on a pump in-pump out cycle, guaranteeing 4h retention for all sludge. The disinfecting ability of TAD exceeded that of AD since it reduced counts of Enterobacteriaceae, thermotolerant coliforms and faecal streptococci to below 103/100ml, rendered cytopathic enteroviruses undetectable and destroyed viability of Ascaris suum ova within 4h. The AD process reduced bacterial counts by 90% and enteroviruses by 99%, but has no effect upon viability of Ascaris ova.

Sustainable Utilization of Sewage Sludge: Review of Technologies

2018 ◽  
Vol 762 ◽  
pp. 121-125 ◽  
Author(s):  
Agnese Stunda-Zujeva ◽  
Imants Kreicbergs ◽  
Olita Medne
Keyword(s):  
Industrial Wastewater ◽  
Biological Treatment ◽  
Mineral Resources ◽  
Wastewater Sludge ◽  
Secondary Source ◽  
Sustainable Utilization ◽  
Toxic Substances ◽  
Sludge Treatment ◽  
Industrial Sludge ◽  
New Methods

Biological treatment of municipal and industrial wastewater becomes more common in EU countries. As a result, the amount of wastewater sludge increases. The political and economic situation in world is requiring new methods for recovery of non-renewable mineral resources. Sludge is great secondary source of many elements. The aim of this research is to summarize available techniques for sustainable utilization of industrial sludge and recovery of critical raw minerals (CRMs). The most common sustainable method is using treated sludge as fertilizer in agriculture due to high content of P, N, C and microelements. However, this method has many restrictions, e.g. it can contain toxic substances or lack of appropriate land. Thermal sludge treatment methods like pyrolysis have developed crucially in last decade and pyrolysis units for sludge treatment are commercially available now. Pyrolysis becomes the most sustainable method due to recovery of CRMs and better energy recovery comparing to incineration.

An innovative sludge management system based on separation of primary and secondary sludge treatment

2004 ◽  
Vol 50 (9) ◽  
pp. 145-153 ◽  
Author(s):  
G. Mininni ◽  
C.M. Braguglia ◽  
R. Ramadori ◽  
M.C. Tomei
Keyword(s):  
Energy Conversion ◽  
Management System ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Nitrogen And Phosphorus ◽  
Sludge Management ◽  
Sludge Treatment ◽  
Gas Treatment ◽  
Primary Sludge ◽  
Secondary Sludge

An innovative sludge management system based on separation of treatment and disposal of primary and secondary sludge is discussed with reference to a sewage treatment plant of 500,000 equivalent person capacity. Secondary sludge, if treated separately from primary sludge, can be recovered in agriculture considering its relatively high content of nitrogen and phosphorus and negligible presence of pathogens and micropollutants. One typical outlet for primary sludge is still incineration which can be optimised by rendering the process auto thermal and significantly reducing the size of the incineration plant units (dryer, fluidised bed furnace, boiler and units for exhaust gas treatment) in comparison with those required for mixed sludge incineration. Biogas produced in anaerobic digestion is totally available for energy conversion when sludge treatment separation is performed, while in the other case a large proportion may be used as fuel in incineration, thus reducing the net electric energy conversion from 0.85-0.9 to 0.35-0.4 MW for the plant considered.

scholarly journals Struvite Precipitation for Sustainable Recovery of Nitrogen and Phosphorus from Anaerobic Digestion Effluents of Swine Manure

2020 ◽  
Vol 12 (20) ◽  
pp. 8574 ◽  
Author(s):  
Hong-Duck Ryu ◽  
Do Young Lim ◽  
Sun-Jung Kim ◽  
Un-Il Baek ◽  
Eu Gene Chung ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Biological Treatment ◽  
Swine Manure ◽  
Molar Ratio ◽  
Optimal Conditions ◽  
Nitrogen And Phosphorus ◽  
Treatment Facilities ◽  
Struvite Precipitation ◽  
Major Factors ◽  
Sustainable Recovery

In this study, we propose the application of struvite precipitation for the sustainable recovery of nitrogen (N) and phosphorus (P) from anaerobic digestion (AD) effluents derived from swine manure. The optimal conditions for four major factors that affect the recovery of N and P were derived by conducting batch experiments on AD effluents obtained from four AD facilities. The optimal conditions were a pH of 10.0, NH4-N:Mg:PO4-P molar ratio of 1:1.4:1, mixing intensity of 240 s−1, and mixing duration of 2 min. Under these optimal conditions, the removal efficiencies of NH4-N and PO4-P were approximately 74% and 83%, respectively, whereas those of Cu and Zn were approximately 74% and 79%, respectively. Herein, a model for swine manure treatment that incorporates AD, struvite precipitation, and biological treatment processes is proposed. We applied this model to 85 public biological treatment facilities in South Korea and recovered 4722 and 51 tons/yr of NH4-N and PO4-P, respectively. The economic analysis of the proposed model’s performance predicts a lack of profitability due to the high cost of chemicals; however, this analysis does not consider the resulting protection of the hydrological environment. Field-scale studies should be conducted in future to prove the effectiveness of the model.

The Influence Factors in Denitrifying Phosphorus Removal

2013 ◽  
Vol 401-403 ◽  
pp. 2084-2087
Author(s):  
Ming Fen Niu ◽  
Si Li ◽  
Hong Jing Jiao ◽  
Jian Wei ◽  
Yuan Yang Sun ◽  
...  
Keyword(s):  
Retention Time ◽  
Phosphorus Removal ◽  
Ph Value ◽  
Influence Factors ◽  
Volume Ratio ◽  
Wastewater Sludge ◽  
Practical Application ◽  
Nitrogen And Phosphorus ◽  
Nitrogen And Phosphorus Removal ◽  
Denitrifying Phosphorus Removal

Denitrifying phosphorus removal can be achieved with the same matrix simultaneous nitrogen and phosphorus removal，is a hot topic of abroad study biological wastewater treatment，This is discussed the Influence factors of anoxic tank NO3- load, dissolved oxygen and the volume ratio of aerobic tank and anoxic tank, pH value of wastewater, sludge retention time (SRT), hydraulic retention time (HRT), mixed liquor suspended solids (MLSS) and temperature on denitrifying phosphorus removal, for denitrifying phosphorus removal process simulation, experimental research and practical application provides a reference and basis.

scholarly journals The Effect of pH And Hydraulic Retention Time On Production Of Volatile Fatty Acids From Primary Sludge Anaerobic Fermentation

2021 ◽  
Author(s):  
Umme Sharmeen Hyder
Keyword(s):  
Fatty Acids ◽  
Retention Time ◽  
Volatile Fatty Acids ◽  
Hydraulic Retention Time ◽  
Wastewater Treatment Plants ◽  
Anaerobic Fermentation ◽  
Nitrogen And Phosphorus ◽  
Primary Sludge ◽  
Effect Of Ph ◽  
Ph Range

Primary Sludge (PS) from wastewater treatment plants contains high biodegradable organic matter and therefore can be used to produce Volatile Fatty Acids (VFAs). The produced VFAs can be utilized in biological nitrogen and phosphorus removal processes as an external carbon source. The objective of this research was to investigate the effect of pH and hydraulic retention time (HRT) on the production of VFAs from PS through the anaerobic fermentation process. The experiments were conducted in both batch and semi-continuous flow regimes using bench scale fermenters under the mesophilic temperature. The Design of experiments included the HRT of 1 – 3 days and pH range of 4.5 - 11.0 for batch and 4.5 - 6.5 for semi-continuous modes. According to the obtained results, the VFAs production increased with an increase in HRT from 1 to 3 days. For the batch study, the pH range for maximum VFAs yield was pH 6.5 –10.0 achieved at HRT of 3 days. For the semi-continuous study, the maximum amount of VFAs production was observed at a pH of 6.5 and HRT of 3 days.

scholarly journals The Effect of pH And Hydraulic Retention Time On Production Of Volatile Fatty Acids From Primary Sludge Anaerobic Fermentation

2021 ◽  
Author(s):  
Umme Sharmeen Hyder
Keyword(s):  
Fatty Acids ◽  
Retention Time ◽  
Volatile Fatty Acids ◽  
Hydraulic Retention Time ◽  
Wastewater Treatment Plants ◽  
Anaerobic Fermentation ◽  
Nitrogen And Phosphorus ◽  
Primary Sludge ◽  
Effect Of Ph ◽  
Ph Range

Primary Sludge (PS) from wastewater treatment plants contains high biodegradable organic matter and therefore can be used to produce Volatile Fatty Acids (VFAs). The produced VFAs can be utilized in biological nitrogen and phosphorus removal processes as an external carbon source. The objective of this research was to investigate the effect of pH and hydraulic retention time (HRT) on the production of VFAs from PS through the anaerobic fermentation process. The experiments were conducted in both batch and semi-continuous flow regimes using bench scale fermenters under the mesophilic temperature. The Design of experiments included the HRT of 1 – 3 days and pH range of 4.5 - 11.0 for batch and 4.5 - 6.5 for semi-continuous modes. According to the obtained results, the VFAs production increased with an increase in HRT from 1 to 3 days. For the batch study, the pH range for maximum VFAs yield was pH 6.5 –10.0 achieved at HRT of 3 days. For the semi-continuous study, the maximum amount of VFAs production was observed at a pH of 6.5 and HRT of 3 days.

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