Anaerobic (UASB) Treatment of Pulp (CTMP) Wastewater and the Toxicity on Granules

1991 ◽  
Vol 23 (10-12) ◽  
pp. 1919-1928 ◽  
Author(s):  
A. Kudo ◽  
K. Kennedy ◽  
E. Andras
Keyword(s):  
Acetic Acid ◽  
Carbon Source ◽  
Mercuric Chloride ◽  
Biogas Production ◽  
Removal Rate ◽  
Anaerobic Sludge ◽  
Anaerobic Culture ◽  
Batch Tests ◽  
Production Ratio ◽  
Specific Loading

A chemi-thermomechanical pulp (CTMP) effluent was treated by upflow anaerobic sludge bed (UASB) reactors. The purpose of the 254 day experiment was to evaluate the acclimatization process for two types of anaerobic granules to CTMP wastewater. One type was an acetic acid enriched culture composed mainly of methanogenic bacteria (reactor I) and the other was a mixed anaerobic culture containing both methanogenic and acidogenic bacteria (reactor II). Initially the reactors were maintained on synthetic feed with acetic acid (reactor I) or sucrose (reactor II) as the carbon source. In order to acclimatize the granules to the wastewater, CTMP wastewater was introduced in 3 stages (10, 50, and 100%). The wastewater contained 8200 mg/l COD, 30-40% of which was non-biodegradable. Both reactors were operated at a specific loading rate of 0.16 g COD/g VSS/day throughout the experiment. Supplementary batch tests using serum bottles were conducted to evaluate toxicity of the CTMP wastewater and two known toxic compounds, pentachlorophenol and mercuric chloride, on mixed anaerobic culture granules. Reactor II acclimatized to the CTMP wastewater better than reactor I. At 50% CTMP wastewater, a COD removal rate of 80% was attained for reactor II, while reactor I removed only 55% of the influent COD. Coincidentally, acetic acid consumption in reactor I was also inhibited after the introduction of 50% CTMP wastewater. It took reactor I 60 days to recover from the CTMP toxicity and to achieve the level of reactor II performance. An unexpected discovery was that the granules from both reactors were completely inhibited 2 weeks after the completion of the 254 day experiment. The granules were stored in a cold room (4°C) for two weeks, during this period, the granules lost the ability to degrade acetic acid. These sick (inhibited) granules re-gained acetoclastic activity when sucrose feed was provided as a carbon source. The results of batch tests showed a dramatic reduction in granule biogas production after exposure both to starvation and to toxicants at levels higher than a certain threshold concentration. The biogas production ratio between the starved and the fed granules was decreased from 89.9% to 43.0% when they were exposed to 50% and 300% CTMP wastewater, respectively. The toxicity of 100% CTMP was equivalent to 7 ppm of pentachlorophenol and 25 ppm of mercuric chloride.

The contribution of thermophilic anaerobic digestion to the stable operation of wastewater sludge treatment

2002 ◽  
Vol 46 (4-5) ◽  
pp. 447-453 ◽  
Author(s):  
J. Zábranská ◽  
M. Dohányos ◽  
P. Jeníček ◽  
P. Zaplatílková ◽  
J. Kutil
Keyword(s):  
Anaerobic Digestion ◽  
Biogas Production ◽  
Removal Rate ◽  
Wastewater Sludge ◽  
Anaerobic Sludge ◽  
Stable Operation ◽  
Sludge Treatment ◽  
Thermophilic Anaerobic Digestion ◽  
Mesophilic Digestion ◽  
Pathogens Removal

Thermophilic anaerobic digestion of sewage sludge has been successfully operated in full-scale tanks almost three years. The higher loading capacity and specific biogas production rate in comparison with mesophilic digestion was proved. Thermophilic anaerobic sludge is also more resistant against foaming problems. Biogas from thermophilic tanks contains less hydrogen sulphide and other malodorous substances. Pathogens removal rate is apparently more efficient in the thermophilic process.

scholarly journals Enrichment of Homoacetogens Converting H2/CO2 into Acids and Ethanol and Simultaneous Methane Production

2021 ◽  
Author(s):  
Yaxue He ◽  
Chiara Cassarini ◽  
Piet N. L. Lens
Keyword(s):  
Acetic Acid ◽  
Butyric Acid ◽  
Methane Production ◽  
Granular Sludge ◽  
Caproic Acid ◽  
Valeric Acid ◽  
Operating Conditions ◽  
Anaerobic Sludge ◽  
Batch Tests ◽  
Ph Decrease

Abstract An anaerobic granular sludge was enriched to utilize H2/CO2 in a continuous gas-fed up-flow anaerobic sludge reactor by applying operating conditions expected to produce acetic acid, butyric acid and ethanol. Three stages of fermentation were found: Stage I with acetic acid accumulation with the highest concentration of 35 mM along with a pH decrease from initial 6 to 4.5. In Stage II, H2/CO2 was replaced by 100% H2 to induce solventogenesis, whereas butyric acid was produced with the highest concentration of 2.5 mM. At Stage III with 10 μM tungsten (W) addition, iso-valeric acid, valeric acid and caproic acid were produced at pH 4.5 -5.0. In the batch tests inoculated with the enriched sludge taken from the bioreactor (day 70), however, methane production occurred at pH 6. Exogenous 15 mM acetate addition enhanced both the H2 and CO2 consumption rate compared to exogenous 10, 30 and 45 mM acetate by the enriched sludge. Exogenous acetate failed to be converted to ethanol using H2 as electron donor by the enriched acetogens.

Denitrification of groundwater using acetic acid as a carbon source

1999 ◽  
Vol 40 (2) ◽  
pp. 53-59 ◽  
Author(s):  
A. Mohseni-Bandpi ◽  
D. J. Elliott ◽  
A. Momeny-Mazdeh
Keyword(s):  
Acetic Acid ◽  
Carbon Source ◽  
Nitrate Nitrogen ◽  
Removal Rate ◽  
Bacterial Species ◽  
Nitrate Removal ◽  
Pilot Scale ◽  
Operating Conditions ◽  
Acid Loading ◽  
Species Being

A pilot scale rotating biological contactor was used to investigate the ability to remove nitrate from groundwater using acetic acid as a carbon source under various operating conditions. The reactor achieved a nitrate removal efficiency of 99 to 83 percent at loading rates of 76 and 490 mg/m2.hr respectively with a flow rate of 2.5 l/min at 20±2°C. The nitrate removal rate was found to be dependent on the influent acetic acid loading rate. The optimum acetic acid to nitrate-nitrogen (A/N) ratio was found to be 4.3:1. Under optimum conditions the effluent nitrate, nitrite-nitrogen and residual acetic acid concentrations were 0.43, 0.03 and 4.4 mg/l. The process generally produced low nitrite intermediate production for up to 100 mg/l influent nitrate-nitrogen. The results of this study show that an anoxic RBC using acetic acid as a carbon source is a convenient and reliable process for the removal of nitrate from water supply. Pseudomonas were found to be the dominant bacterial species with species being Ps. stutzeri and Ps. fluorescence.

Treatment of cane sugar mill wastewater in an upflow anaerobic sludge bed reactor

2009 ◽  
Vol 60 (5) ◽  
pp. 1347-1352 ◽  
Author(s):  
P. Mijaylova Nacheva ◽  
G. Moeller Chávez ◽  
J. Matías Chacón ◽  
A. Canul Chuil
Keyword(s):  
Sugar Cane ◽  
Biological Treatment ◽  
Biogas Production ◽  
Removal Rate ◽  
Stable Process ◽  
Uasb Reactor ◽  
Organic Load ◽  
Anaerobic Sludge ◽  
Process Performance ◽  
Kinetic Coefficients

The performance of a mesophilic UASB reactor was studied for the treatment of sugar cane mill wastewater previously pre-treated for solid separation. The experimental work was carried out in a reactor with 80 L total volume. Four organic loads were applied and the process performance was evaluated during two months for each experimental stage. Removal efficiencies higher than 90% were obtained with organic loads up to 16 kg COD m−3 d−1. Stable process performance and high biogas production were obtained. The COD removal rate increased substantially with the load increase to 24 kg COD m−3 d−1. However, the obtained removal was of only 78–82%, which can be attributed to the accumulation of volatile organic acids. The kinetic coefficients were obtained using first order model for the substrate removal rate and Monod's equation for bacteria specific growth rate. The UASB reactor is a good option for the biological treatment of pre-treated sugar cane mill wastewaters. The discharge requirements for COD concentration can be accomplished if the reactor is operated at a low organic load of 4 kg COD m−3 d−1. At higher loads, an additional biological treatment stage is needed.

scholarly journals Mixed carbon source improves deep denitrification performance in up-flow anaerobic sludge bed reactor

2020 ◽  
Vol 81 (4) ◽  
pp. 763-772
Author(s):  
Hong Xiao ◽  
Jiaojiao Wu ◽  
Hong Peng ◽  
Zhongyao Jiang
Keyword(s):  
Microbial Community ◽  
Carbon Source ◽  
Sodium Acetate ◽  
High Throughput Sequencing ◽  
Removal Rate ◽  
Carbon Sources ◽  
Anaerobic Sludge ◽  
Rrna Gene ◽  
Mixed Carbon Source ◽  
N Removal

Abstract To investigate the advantages of mixed carbon source over a single one in deep denitrification, sodium acetate, glucose and their mixture were used as carbon sources in present study. Denitrification performance, effluent pH, microbial community and carbon source cost were taken into account. With the same influent NO3–-N concentration of 50 mg/L and the same C/N ratio of 1.5, the NO3–-N removal rate with the mixed carbon source (96.53%) was slightly lower than that with sodium acetate (98.15%), but significantly higher than that with glucose (74.69%). The specific denitrification rates of the sodium acetate, glucose and sodium acetate/glucose reactor were 47.7, 29.7 and 45.4 mg N/g VSS d, respectively. The effluent pH with sodium acetate varied in the range of 9.13–9.60, exceeding the discharge standard limit of 9.0, whereas the sodium acetate/glucose reactor could keep pH in the range of 7.80–8.23. The 16S rRNA gene-based high-throughput sequencing revealed that carbon sources determined the microbial community structure and the sludge Shannon index with the mixed carbon source was the highest. Furthermore, cost estimation indicated that the mixed carbon source was the cheapest. This study is significant as it tests reasonable selection of carbon sources for deep denitrification in practice.

scholarly journals Assessment of the potential for biogas production from wheat straw leachate in upflow anaerobic sludge blanket digesters

2012 ◽  
Vol 66 (12) ◽  
pp. 2737-2744 ◽  
Author(s):  
S. Idrus ◽  
C. J. Banks ◽  
S. Heaven
Keyword(s):  
Wheat Straw ◽  
Cold Water ◽  
Biogas Production ◽  
Removal Rate ◽  
Salt Content ◽  
Gas Production ◽  
Upflow Anaerobic Sludge Blanket ◽  
Anaerobic Sludge ◽  
Energy Yield ◽  
Anaerobic Sludge Blanket

Wheat straw is a major potential source of waste biomass for renewable energy production, but its high salt content causes problems in combustion. The salts can be removed by washing, but this process also removes a proportion of the organic material which could potentially be recovered by anaerobic digestion of the washwater leachate. This approach would maximise the overall energy yield in an integrated process in which washwater could be recycled after further desalting. Leachate from cold water washing with a chemical oxygen demand (COD) of 1.2 g l−1 was fed to mesophilic upflow anaerobic sludge blanket (UASB) digesters at a loading rate of 1 g COD l−1 day−1 to determine the energy yield and any detrimental effects of the leached salts on the process. The specific methane production was 0.29 l CH4 g−1 CODadded, corresponding to a COD removal rate of 84%. Light metal cations in the leachate, especially potassium, were found to accumulate in the digesters and appeared to have a synergistic effect up to a concentration of ∼6.5 mg K g−1 wet weight of the granular sludge, but further accumulation caused inhibition of methanogenesis. It was shown that gas production in the inhibited digesters could be restored within 12 days by switching the feed to a synthetic sewage, which washed the accumulated K out of the digesters.

BIOGAS PRODUCTION IN THE CONCENTRATED DISTILLERY WASTEWATER TREATMENT

2018 ◽  
pp. 51-59 ◽  
Author(s):  
N. Golub ◽  
M. Potapova ◽  
M. Shinkarchuk ◽  
O. Kozlovets
Keyword(s):  
Wastewater Treatment ◽  
Dry Matter ◽  
Ph Value ◽  
Biogas Production ◽  
Anaerobic Sludge ◽  
Methane Formation ◽  
Maximum Output ◽  
Processing Technologies ◽  
Spent Wash ◽  
Distillery Spent Wash

The paper deals with the waste disposal problem of the alcohol industry caused by the widespread use of alcohol as biofuels. In the technology for the production of alcohol from cereal crops, a distillery spent wash (DSW) is formed (per 1 dm3 of alcohol – 10–20 dm3 DSW), which refers to highly concentrated wastewater, the COD value reaches 40 g O2/dm3. Since the existing physical and chemical methods of its processing are not cost-effective, the researchers develop the processing technologies for its utilization, for example, an anaerobic digestion. Apart from the purification of highly concentrated wastewater, the advantage of this method is the production of biogas and highquality fertilizer. The problems of biotechnology for biogas production from the distillery spent wash are its high acidity–pH 3.7–5.0 (the optimum pH value for the methanogenesis process is 6.8–7.4) and low nitrogen content, the lack of which inhibits the development of the association of microorganisms. In order to solve these problems, additional raw materials of various origins (chemical compounds, spent anaerobic sludge, waste from livestock farms, etc.) are used. The purpose of this work is to determine the appropriate ratio of the fermentable mixture components: cosubstrate, distillery spent wash and wastewater of the plant for co-fermentation to produce an energy carrier (biogas) and effective wastewater treatment of the distillery. In order to ensure the optimal pH for methanogenesis, poultry manure has been used as a co-substrate. The co-fermentation process of DSW with manure has been carried out at dry matter ratios of 1:1, 1:3, 1:5, 1:7 respectively. It is found that when the concentration of manure in the mixture is insufficient (DSW/manure – 1:1, 1:3), the pH value decreases during fermentation which negatively affects methane formation; when the concentration of manure in the mixture is increased (DSW/manure – 1:5, 1:7), the process is characterized by a high yield of biogas and methane content. The maximum output of biogas with a methane concentration of 70 ± 2% is observed at the ratio of components on a dry matter “wastewater: DSW: manure” – 0,2:1:7 respectively. The COD reduction reaches a 70% when using co-fermentation with the combination of components “wastewater: DSW: manure” (0,3:1:5) respectively.

Simulation of the Impact of Higher Ammonia Recycle Loads Caused by Upgrading Anaerobic Sludge Digesters

2005 ◽  
Vol 40 (4) ◽  
pp. 491-499 ◽  
Author(s):  
Jeremy T. Kraemer ◽  
David M. Bagley
Keyword(s):  
Anaerobic Digestion ◽  
Biogas Production ◽  
Treatment Plant ◽  
Anaerobic Sludge ◽  
Content Increase ◽  
Limited Information ◽  
Dynamic Simulations ◽  
Treatment Train ◽  
Temperature Liquid ◽  
The Impact

Abstract Upgrading conventional single-stage mesophilic anaerobic digestion to an advanced digestion technology can increase sludge stability, reduce pathogen content, increase biogas production, and also increase ammonia concentrations recycled back to the liquid treatment train. Limited information is available to assess whether the higher ammonia recycle loads from an anaerobic sludge digestion upgrade would lead to higher discharge effluent ammonia concentrations. Biowin, a commercially available wastewater treatment plant simulation package, was used to predict the effects of anaerobic digestion upgrades on the liquid train performance, especially effluent ammonia concentrations. A factorial analysis indicated that the influent total Kjeldahl nitrogen (TKN) and influent alkalinity each had a 50-fold larger influence on the effluent NH3 concentration than either the ambient temperature, liquid train SRT or anaerobic digestion efficiency. Dynamic simulations indicated that the diurnal variation in effluent NH3 concentration was 9 times higher than the increase due to higher digester VSR. Higher recycle NH3 loads caused by upgrades to advanced digestion techniques can likely be adequately managed by scheduling dewatering to coincide with periods of low influent TKN load and ensuring sufficient alkalinity for nitrification.

Effect of sulfate on anaerobic processes fed with dual substrates

1995 ◽  
Vol 31 (9) ◽  
pp. 101-107 ◽  
Author(s):  
Chongchin Polprasert ◽  
Charles N. Haas
Keyword(s):  
Acetic Acid ◽  
Sulfate Reduction ◽  
Mixed Culture ◽  
Biogas Production ◽  
Cod Removal ◽  
Methane Formation ◽  
Batch Mode ◽  
Sulfate Reducing ◽  
Anaerobic Reactors ◽  
Optimal Feed

Anaerobic reactors were operated in a semi-batch mode and fed with the dual substrates glucose (G) plus acetic acid (Ac) as primary organic sources to study the effect of sulfate on COD oxidation. With glucose, COD removal by methane formation was seriously inhibited, resulting in COD accumulation in the reactor. Although acetic acid can be consumed by some sulfate-reducing species, it was not a major substrate for sulfate reduction, but was largely responsible for methane formation in the anaerobic mixed culture used in this study. With dual substrates, extreme inhibition of methanogenesis did not occur as did with glucose alone. Instead, methanogens were found to work in harmony with acid formers as well as sulfate reducers to oxidise COD. Interestingly, from 12-hour monitoring, increased G/Ac COD ratios decreased COD removal rates as well as biogas production, but resulted in higher sulfate reduction. This suggests that there should be an optimal feed G/Ac COD ratio, for which removal of both organics could be maximised.

scholarly journals Microbial Removal of Pb(II) Using an Upflow Anaerobic Sludge Blanket (UASB) Reactor

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 512
Author(s):  
Jeremiah Chimhundi ◽  
Carla Hörstmann ◽  
Evans M. N. Chirwa ◽  
Hendrik G. Brink
Keyword(s):  
Treatment Process ◽  
Removal Rate ◽  
Upflow Anaerobic Sludge Blanket ◽  
Uasb Reactor ◽  
Anaerobic Sludge ◽  
Reduction Potentials ◽  
Oxidation Reduction ◽  
Anaerobic Sludge Blanket ◽  
Microbial Removal ◽  
Maximum Removal

The main objective of this study was to achieve the continuous biorecovery and bioreduction of Pb(II) using an industrially obtained consortia as a biocatalyst. An upflow anaerobic sludge blanket reactor was used in the treatment process. The bioremediation technique that was applied made use of a yeast extract as the microbial substrate and Pb(NO3)2 as the source of Pb(II). The UASB reactor exhibited removal efficiencies of between 90 and 100% for the inlet Pb concentrations from 80 to 2000 ppm and a maximum removal rate of 1948.4 mg/(L·d) was measured. XRD and XPS analyses of the precipitate revealed the presence of Pb0, PbO, PbS and PbSO4. Supporting experimental work carried out included growth measurements, pH, oxidation–reduction potentials and nitrate levels.

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