Anammox brings WWTP closer to energy autarky due to increased biogas production and reduced aeration energy for N-removal

2008 ◽  
Vol 57 (3) ◽  
pp. 383-388 ◽  
Author(s):  
H. Siegrist ◽  
D. Salzgeber ◽  
J. Eugster ◽  
A. Joss
Keyword(s):  
Hydraulic Retention Time ◽  
Biogas Production ◽  
Sludge Treatment ◽  
N Removal ◽  
Secondary Sludge ◽  
Organic Carbon Source ◽  
Anammox Process ◽  
Dry Weather Flow ◽  
Heterotrophic Denitrification ◽  
Bod Removal

Fifty years ago when only BOD was removed at municipal WWTPs primary clarifiers were designed with 2–3 hours hydraulic retention time (HRT). This changed with the introduction of nitrogen removal in activated sludge treatment that needed more BOD for denitrification. The HRT of primary clarification was reduced to less than one hour for dry weather flow with the consequence that secondary sludge had to be separately thickened and biogas production was reduced. Only recently the ammonia rich digester liquid (15–20% of the inlet ammonia load) could be treated with the very economic autotrophic nitritation/anammox process requiring half of the aeration energy and no organic carbon source compared to nitrification and heterotrophic denitrification. With the introduction of this new innovative digester liquid treatment the situation reverts, allowing us to increase HRT of the primary clarifier to improve biogas production and reduce aeration energy for BOD removal and nitrification at similar overall N-removal.

scholarly journals Effect of Mixing Regimes on Cow Manure Digestion in Impeller Mixed, Unmixed and Chinese Dome Digesters

Energies ◽  
2019 ◽  
Vol 12 (13) ◽  
pp. 2540
Author(s):  
Abiodun O. Jegede ◽  
Grietje Zeeman ◽  
Harry Bruning
Keyword(s):  
Urban Areas ◽  
Hydraulic Retention Time ◽  
Biogas Production ◽  
Gas Production ◽  
Cow Manure ◽  
Volatile Solid ◽  
Treatment Efficiency ◽  
Ambient Temperatures ◽  
Ch4 Production ◽  
Mixing Regime

This study examines the effect of mixing on the performance of anaerobic digestion of cow manure in Chinese dome digesters (CDDs) at ambient temperatures (27–32 °C) in comparison with impeller mixed digesters (STRs) and unmixed digesters (UMDs) at the laboratory scale. The CDD is a type of household digester used in rural and pre-urban areas of developing countries for cooking. They are mixed by hydraulic variation during gas production and gas use. Six digesters (two of each type) were operated at two different influent total solids (TS) concentration, at a hydraulic retention time (HRT) of 30 days for 319 days. The STRs were mixed at 55 rpm, 10 min/hour; the unmixed digesters were not mixed, and the Chinese dome digesters were mixed once a day releasing the stored biogas under pressure. The reactors exhibited different specific biogas production and treatment efficiencies at steady state conditions. The STR 1 exhibited the highest methane (CH4) production and treatment efficiency (volatile solid (VS) reduction), followed by STR 2. The CDDs performed better (10% more methane) than the UMDs, but less (approx. 8%) compared to STRs. The mixing regime via hydraulic variation in the CDD was limited despite a higher volumetric biogas rate and therefore requires optimization.

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.

Nitrogen elimination from sludge treatment reject water – comparison of the steam-stripping and denitrification processes

1994 ◽  
Vol 30 (6) ◽  
pp. 41-51 ◽  
Author(s):  
Burkhard Teichgräber ◽  
Andreas Stein
Keyword(s):  
Organic Nitrogen ◽  
Hydraulic Retention Time ◽  
Surface Load ◽  
Operational Experience ◽  
Sludge Treatment ◽  
Reject Water ◽  
Total Treatment ◽  
Treatment Facilities ◽  
Nitrogen Elimination ◽  
Denitrification Process

Steam stripping and nitrification/denitrification for the elimination of nitrogen from sludge treatment reject water from the Central Sludge Treatment Facilities (CSTF) of the Emschergenossenschaft in Bottrop were tested in half-scale pilot plants. More than 90% efficiency could be achieved with both systems; the nitrification/denitrification process also removed organic nitrogen. Operational experience has shown that full scale application of both systems is possible. The design surface load of the stripping column has been evaluated as 10 m3/(m2*h) and the steam/water ratio as 0.12 t/m3. The nitrification/denitrification process can be designed for 0.07 kgN/(kg MLSS*d) and 1.4 days hydraulic retention time. Total treatment costs are estimated to be between 5 and 7.5 DM/kg N.

scholarly journals Effect of Hydraulic Retention Time on Biogas Production from Cow Dung in A Semi Continuous Anaerobic Digester

2018 ◽  
Vol 7 (2) ◽  
pp. 93-100 ◽  
Author(s):  
Agus Haryanto ◽  
Sugeng Triyono ◽  
Nugroho Hargo Wicaksono
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Biogas Production ◽  
Stable Condition ◽  
Anaerobic Digester ◽  
Organic Loading Rate ◽  
Cow Dung ◽  
Biogas Yield ◽  
Average Analysis

The efficiency of biogas production in semi-continuous anaerobic digester is influenced by several factors, among other is loading rate. This research aimed at determining the effect of hydraulic retention time (HRT) on the biogas yield. Experiment was conducted using lab scale self-designed anaerobic digester of 36-L capacity with substrate of a mixture of fresh cow dung and water at a ratio of 1:1. Experiment was run with substrate initial amount of 25 L and five treatment variations of HRT, namely 1.31 gVS/L/d (P1), 2.47 gVS/L/d (P2), 3.82 gVS/L/d (P3), 5.35 gVS/L/d (P4) and 6.67 gVS/L/d (P5). Digester performance including pH, temperature, and biogas yield was measured every day. After stable condition was achieved, biogas composition was analyzed using a gas chromatograph. A 10-day moving average analysis of biogas production was performed to compare biogas yield of each treatment. Results showed that digesters run quite well with average pH of 6.8-7.0 and average daily temperature 28.7-29.1. The best biogas productivity (77.32 L/kg VSremoval) was found in P1 treatment (organic loading rate of 1.31 g/L/d) with biogas yield of 7.23 L/d. With methane content of 57.23% treatment P1 also produce the highest methane yield. Biogas production showed a stable rate after the day of 44. Modified Gompertz kinetic equation is suitable to model daily biogas yield as a function of digestion time.Article History: Received March 24th 2018; Received in revised form June 2nd 2018; Accepted June 16th 2018; Available onlineHow to Cite This Article: Haryanto, A., Triyono, S., and Wicaksono, N.H. (2018) Effect of Loading Rate on Biogas Production from Cow Dung in A Semi Continuous Anaerobic Digester. Int. Journal of Renewable Energy Development, 7(2), 93-100.https://doi.org/10.14710/ijred.7.2.93-100

Activated Sludge Treatment of Ethoxylate Surfactants at High Industrial Use Concentrations

1988 ◽  
Vol 20 (11-12) ◽  
pp. 125-130 ◽  
Author(s):  
J. P. Salanitro ◽  
G. C. Langston ◽  
P. B. Dorn ◽  
L. Kravetz
Keyword(s):  
Activated Sludge ◽  
Fathead Minnow ◽  
Treatment Process ◽  
Aquatic Toxicity ◽  
Alcohol Ethoxylate ◽  
Sludge Treatment ◽  
Nonylphenol Ethoxylate ◽  
Incomplete Removal ◽  
Industrial Use ◽  
Bod Removal

The primary degradation of a linear alcohol ethoxylate (AE) and a branched nonylphenol ethoxylate (NPE) was investigated in bench-scale activated sludge units treating a synthetic sewage feed. Biotreaters were gradually adapted to 10-100 mg/ℓ surfactant and effluents monitored for loss of nonionic ethoxylate, foaming, feed BOD removal, nitrification and biosolids growth. Both surfactants were degraded at influent doses of 10-40 mg/ℓ. Substantial BOD breakthrough, loss of nitrification, aerator foaming and incomplete removal of the NPE surfactant occurred when fed at 80 and 100 mg/ℓ while the unit treating AE was unaffected by high surfactant levels. Comparative aquatic toxicity of the biotreated waste at high surfactant levels indicated that the NPE effluent was acutely toxic (EC50, 7-15% effluent) to the fathead minnow and Daphnia while that of the AE unit was non-toxic (EC50, > 100% effluent) to these same species. These studies indicate that the treatment of wastes containing high levels of NPE ethoxylates may adversely impact an activated sludge process in incomplete degradation and foaming, impaired BOD removal, loss in nitrification and the formation of toxic effluents. AE surfactants, however, undergo extensive microbial degradation and cause little or no impact on the activated sludge treatment process.

scholarly journals The feasibility of trace element supplementation for stable operation of wheat stillage-fed biogas tank reactors

2011 ◽  
Vol 64 (2) ◽  
pp. 320-325 ◽  
Author(s):  
J. Gustavsson ◽  
B. H. Svensson ◽  
A. Karlsson
Keyword(s):  
Trace Element ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Biogas Production ◽  
Organic Loading Rate ◽  
Stable Operation ◽  
Organic Loading ◽  
Process Stability ◽  
Volatile Solids ◽  
High Sulfate

The aim of this study was to investigate the effect of trace element supplementation on operation of wheat stillage-fed biogas tank reactors. The stillage used was a residue from bio-ethanol production, containing high levels of sulfate. In biogas production, high sulfate content has been associated with poor process stability in terms of low methane production and accumulation of process intermediates. However, the results of the present study show that this problem can be overcome by trace element supplementations. Four lab-scale wheat stillage-fed biogas tank reactors were operated for 345 days at a hydraulic retention time of 20 days (37 °C). It was concluded that daily supplementation with Co (0.5 mg L−1), Ni (0.2 mg L−1) and Fe (0.5 g L−1) were required for maintaining process stability at the organic loading rate of 4.0 g volatile solids L−1 day−1.

scholarly journals Evaluation of Feasibility of Using the Bacteriophage T4 Lysozyme to Improve the Hydrolysis and Biochemical Methane Potential of Secondary Sludge

Energies ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3644
Author(s):  
Sangmin Kim ◽  
Seung-Gyun Woo ◽  
Joonyeob Lee ◽  
Dae-Hee Lee ◽  
Seokhwan Hwang
Keyword(s):  
Cell Wall ◽  
Bacterial Cell ◽  
Wastewater Treatment Plants ◽  
Biogas Production ◽  
Bacteriophage T4 ◽  
Suspended Solid ◽  
T4 Lysozyme ◽  
Biochemical Methane Potential ◽  
Secondary Sludge ◽  
Methane Potential

Anaerobic digestion (AD) of secondary sludge is a rate-limiting step due to the bacterial cell wall. In this study, experiments were performed to characterize secondary sludges from three wastewater treatment plants (WWTPs), and to investigate the feasibility of using bacteriophage lysozymes to speed up AD by accelerating the degradation of bacterial cell walls. Protein was the main organic material (67.7% of volatile solids in the sludge). The bacteriophage T4 lysozyme (T4L) was tested for hydrolysis and biochemical methane potential. Variations in the volatile suspended solid (VSS) concentration and biogas production were monitored. The VSS reduction efficiencies by hydrolysis using T4L for 72 h increased and ranged from 17.8% to 26.4%. Biogas production using T4L treated sludges increased and biogas production was increased by as much as 82.4%. Biogas production rate also increased, and the average reaction rate coefficient of first-order kinetics was 0.56 ± 0.02/d, which was up to 47.5% higher compared to the untreated samples at the maximum. Alphaproteobacteria, Betaproteobacteria, Flavobacteriia, Gammaproteobacteria, and Sphingobacteriia were major microbial classes in all sludges. The interpretation of the microbial community structure indicated that T4L treatment is likely to increase the rate of cell wall digestion.

Investigations on Activated Sludge Microfauna and Treatment Plant Disfunctions

1992 ◽  
Vol 26 (9-11) ◽  
pp. 2519-2522 ◽  
Author(s):  
M. Cossignani ◽  
L. Cingolani ◽  
L. Giacché ◽  
R. Miliani
Keyword(s):  
Activated Sludge ◽  
Process Parameters ◽  
Treatment Plant ◽  
Factorial Analysis ◽  
Sludge Treatment ◽  
Bod Removal

Factorial analysis was applied to data from a series of 24 samples collected in an activated sludge treatment plant from October 1990 to April 1991. Relationships between process parameters and protozoans suggested that Epistylis plicatilis aboundance is related to the best conditions of BOD removal. Moreover the presence of Litonotus fasciola related to a poor floc settling.

Treatment of Monosodium Glutamate Fermentation Wastewater with Anaerobic Biological Fluidized Bed Process

1990 ◽  
Vol 22 (9) ◽  
pp. 149-155 ◽  
Author(s):  
Szu-Kung Tseng ◽  
Min-Ray Lin
Keyword(s):  
Fluidized Bed ◽  
Removal Efficiency ◽  
Biogas Production ◽  
Monosodium Glutamate ◽  
Organic Loading ◽  
Operation Condition ◽  
Glutamate Fermentation ◽  
Fluidized Bed Process ◽  
Very High ◽  
Bod Removal

This study is to explore the feasibility of the treatment of the MSG Fermentation wastewater by AFBBR (Anaerobic Biologial Fluidized Bed Reactor) Method, and intends to solve the serious pollution problem of MSG industry by the advantages of AFBBR Method. The results show that the wastewater BOD removal efficiency is very high due to this treatment. When the organic loading is below 14.0 kg-BOD/m3.day, the BOD removal efficiency can reach 90% or more. Since the wastewater contains the undissolvable difficult biodegradation organic matter, the COD removal efficiency only reaches 65% maximum. The methane content in biogas can achieve 80.8%. When the digestion temperature is 35°C, biogas production per kg is maximum 367.8 1. The treatment results indicate if the organic loading is in the range of 10.1-31.1 kg-COD/m3.d, and the operation condition is appropriate, we will get a very good digestion efficiency, i.e. the feasibility of this method for MSG Fermentation Wastewater Treatment is very high.

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