External Carbon Source Facilitates Indirect Cr (VI) Bioreduction Process by Anaerobic Sludge Produced from Kitchen Waste

This study presented the investigation on indirect Cr (VI) bioreduction process by anaerobic sludge produced from kitchen waste (ASKW) using an external source of glucose and sulfate to favor the reducing environment. These compounds were added at the beginning of the experiment along with 500 mg·L−1 Cr (VI). The system containing 1 g of glucose and 2 g of sulfate attained a higher reduction, which was 10% higher than that of the control experiment. This study indicated that a neutral environment (pH ~7), along with a high release of polysaccharides (PS), improved the removal efficiency by Cr (VI) bioreduction process. Desulfovibrio and Sulfurospirillum (genus level), which accounted for 3% and 1% of the whole microorganism, respectively, were responsible for the sulfidogenic reaction. Additionally, Thermovirga (genus level) reduced from 14% to 11% and 10%. These microorganisms contributed to dominating the indirect Cr (VI) bioreduction process. SEM and FTIR analysis of the sludges obtaining from the indirect Cr (VI) bioreduction systems indicated that the external glucose could facilitate the formation of looser porous structures and richer functional groups of sludges, thus adsorbing more Cr (III) to reduce its toxicity. Meanwhile, the intensity of the hydroxyl bond, which possesses strong reducibility, was much higher after adding external glucose. Chromate reductase gene (chrR) and sulfite reductase gene (dsrA) contributed to the indirect Cr (VI) bioreduction process. These might be the main mechanisms of the external glucose acting on indirect Cr (VI) bioreduction by ASKW.

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Study on Granulation of Anaerobic Sludge in UASB Reactor Adding Cationic Polymer Treating Low Strength Wastewater at Room Temperature

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.71-78.2974 ◽

2011 ◽

Vol 71-78 ◽

pp. 2974-2977 ◽

Cited By ~ 1

Author(s):

Zong Lian She ◽

Jian Wu ◽

Xiao Hui Fu ◽

En Shi ◽

Bao Shi Li ◽

...

Keyword(s):

Removal Efficiency ◽

Room Temperature ◽

Control Experiment ◽

Cationic Polymer ◽

Cod Removal ◽

Uasb Reactor ◽

Anaerobic Sludge ◽

Cod Removal Efficiency ◽

Low Strength ◽

To Receive

Effect of cationic polymer on granulation and COD removal efficiency in lab scale UASB reactors was examined, treating low-strength wastewater (COD 300-500mg l-1) at room temperature. It was shown that cationic polymer was more effective for enhancing sludge granulation and COD removal efficiency as compared to the control experiment (without additives). After day 166 of operation, the amount of granules size above 0.5mm accounted for 32.1% of total sludge, higher than that of control experiment (19.3%). At 1.03 kg COD m-3 d-1 of OLR and 9.8 h of HRT, the effluent VFA had a maximum value of 168mg l-1 and 240mg l-1 in Reactor A and B respectively. The polymer-amended reactor took 36days to receive 1.44 kg COD m-3 d-1 of OLR at the 7.8 h of HRT, shorter than the control reactor (54days). The two reactors obtained above 80% in COD removal efficiency. It is shown that UASB reactor can also achieve higher COD removal treating low strength wastewater at room temperature.

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Anaerobic on-site black water and kitchen waste treatment using UASB-septic tanks at low temperatures

Water Science & Technology ◽

10.2166/wst.2006.497 ◽

2006 ◽

Vol 54 (2) ◽

pp. 143-149 ◽

Cited By ~ 4

Author(s):

S. Luostarinen ◽

J. Rintala

Keyword(s):

Nitrogen Removal ◽

Waste Treatment ◽

Oxygen Demand ◽

Biofilm Reactor ◽

Upflow Anaerobic Sludge Blanket ◽

Septic Tank ◽

Anaerobic Sludge ◽

Kitchen Waste ◽

Black Water ◽

Anaerobic Sludge Blanket

Anaerobic on-site treatment of black water (BW) and a mixture of black water and kitchen waste (BWKW) was studied in a two-phased upflow anaerobic sludge blanket septic tank (UASBst) at 10–20 °C. The processes were fed either continuously or discontinuously (twice per weekday). Moreover, BWKW was post-treated for nitrogen removal in an intermittently aerated moving bed biofilm reactor (MBBR) at 20 °C. Removal of total chemical oxygen demand (CODt) was efficient at minimum 90% with all three UASBst at all temperatures. Removal of dissolved COD (CODdis) was also high at approx. 70% with continuously fed BW and discontinuously fed BWKW, while with discontinuous BW feeding it was 20%. Temperature decrease had little effect on COD removals, though the need for phase 2 increased with decreasing temperature, especially with BWKW. Post-treatment of BWKW in MBBR resulted in approx. 50% nitrogen removal, but suffered from lack of carbon for denitrification. With carbon addition, removal of ca. 83% was achieved.

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Methanomethylovorans thermophila sp. nov., a thermophilic, methylotrophic methanogen from an anaerobic reactor fed with methanol

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijs.0.63818-0 ◽

2005 ◽

Vol 55 (6) ◽

pp. 2465-2470 ◽

Cited By ~ 66

Author(s):

B. Jiang ◽

S. N. Parshina ◽

W. van Doesburg ◽

B. P. Lomans ◽

A. J. M. Stams

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Gene Sequence ◽

Upflow Anaerobic Sludge Blanket ◽

16S Rrna Gene Sequence ◽

Anaerobic Sludge ◽

Rrna Gene ◽

Rrna Gene Sequence ◽

Reductase Gene ◽

The 16S Rrna Gene

A novel thermophilic, obligately methylotrophic, methanogenic archaeon, strain L2FAWT, was isolated from a thermophilic laboratory-scale upflow anaerobic sludge blanket reactor fed with methanol as the carbon and energy source. Cells of strain L2FAWT were non-motile, irregular cocci, 0·7–1·5 μm in diameter and usually occurred singly (sometimes forming clusters of two or four cells). The cells stained Gram-negative and lysed immediately in 0·1 % (w/v) SDS. Growth was inhibited by chloramphenicol and tetracycline, but not by penicillin, bacitracin, spectinomycin, vancomycin or kanamycin. Methanol and mono-, di- and trimethylamine were used as substrates, but H2/CO2, formate, acetate, propanol, dimethyl sulfide and methanethiol were not. The temperature range for growth was 42–58 °C, with an optimum at 50 °C. The fastest growth was observed at a salinity below 100 mM NaCl; no growth occurred above 300 mM NaCl. The optimal pH for growth was 6·5; growth was observed from pH 5 to pH 7·5. The G+C content of the genomic DNA was 37·6 mol%. Analysis of the 16S rRNA gene sequence and the partial methyl-CoM reductase gene sequence revealed that the organism was phylogenetically closely related to Methanomethylovorans hollandica DMS1T (98 % similarity for the 16S rRNA gene sequence and 91 % similarity for the methyl-CoM reductase gene sequence). The DNA–DNA relatedness between L2FAWT and Methanomethylovorans hollandica DMS1T was 46 %. On the basis of these results, strain L2FAWT (=DSM 17232T=ATCC BAA-1173T) represents the type strain of a novel species, for which the name Methanomethylovorans thermophila sp. nov. is proposed.

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Visual Search Facilitation in Repeated Displays Depends on Visuospatial Working Memory

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000125 ◽

2012 ◽

Vol 59 (1) ◽

pp. 47-54 ◽

Cited By ~ 16

Author(s):

Angela A. Manginelli ◽

Franziska Geringswald ◽

Stefan Pollmann

Keyword(s):

Working Memory ◽

Visual Search ◽

Control Experiment ◽

Memory Load ◽

Contextual Cueing ◽

Long Term Memory ◽

Visuospatial Working Memory ◽

Working Memory Load ◽

Memory Resources

When distractor configurations are repeated over time, visual search becomes more efficient, even if participants are unaware of the repetition. This contextual cueing is a form of incidental, implicit learning. One might therefore expect that contextual cueing does not (or only minimally) rely on working memory resources. This, however, is debated in the literature. We investigated contextual cueing under either a visuospatial or a nonspatial (color) visual working memory load. We found that contextual cueing was disrupted by the concurrent visuospatial, but not by the color working memory load. A control experiment ruled out that unspecific attentional factors of the dual-task situation disrupted contextual cueing. Visuospatial working memory may be needed to match current display items with long-term memory traces of previously learned displays.

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Studies on effect of Trigonella root extract as kitchen waste on Rhizobium Colonies of Cajanus cajan

International Journal of Scientific Research ◽

10.15373/22778179/nov2013/2 ◽

2012 ◽

Vol 2 (11) ◽

pp. 4-5

Author(s):

Aparna Gade ◽

◽

Sachin S Bhagat ◽

Anil Bhalerao

Keyword(s):

Cajanus Cajan ◽

Root Extract ◽

Kitchen Waste

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BIOGAS PRODUCTION IN THE CONCENTRATED DISTILLERY WASTEWATER TREATMENT

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2018.25-30.051-059 ◽

2018 ◽

pp. 51-59 ◽

Cited By ~ 1

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.

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Interconnectivity of Bioceramic Scaffolds with Different Porous Structures and Their Fluid Velocity Distribution Analyzed by Micro-CT Computer Modeling

Journal of Inorganic Materials ◽

10.15541/jim20140204 ◽

2015 ◽

Vol 30 (1) ◽

pp. 71 ◽

Cited By ~ 2

Author(s):

LUO Pin-Feng ◽

ZHI Wei ◽

ZHANG Jing-Wei ◽

SHI Feng ◽

DUAN Ke ◽

...

Keyword(s):

Velocity Distribution ◽

Computer Modeling ◽

Fluid Velocity ◽

Porous Structures ◽

Micro Ct

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Analysis and balance of phosphorous removal from wastewater at urban wastewater treatment plant

Pollack Periodica ◽

10.1556/606.2020.15.2.13 ◽

2020 ◽

Vol 15 (2) ◽

pp. 142-151

Author(s):

Peter Lukac ◽

Lubos Jurik

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Wastewater Treatment Plants ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Phosphorus Recovery ◽

Anaerobic Sludge ◽

Biological Phosphorus Removal ◽

The Mean

Abstract:Phosphorus is a major substance that is needed especially for agricultural production or for the industry. At the same time it is an important component of wastewater. At present, the waste management priority is recycling and this requirement is also transferred to wastewater treatment plants. Substances in wastewater can be recovered and utilized. In Europe (in Germany and Austria already legally binding), access to phosphorus-containing sewage treatment is changing. This paper dealt with the issue of phosphorus on the sewage treatment plant in Nitra. There are several industrial areas in Nitra where record major producers in phosphorus production in sewage. The new wastewater treatment plant is built as a mechanicalbiological wastewater treatment plant with simultaneous nitrification and denitrification, sludge regeneration, an anaerobic zone for biological phosphorus removal at the beginning of the process and chemical phosphorus precipitation. The sludge management is anaerobic sludge stabilization with heating and mechanical dewatering of stabilized sludge and gas management. The aim of the work was to document the phosphorus balance in all parts of the wastewater treatment plant - from the inflow of raw water to the outflow of purified water and the production of excess sludge. Balancing quantities in the wastewater treatment plant treatment processes provide information where efficient phosphorus recovery could be possible. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. The mean daily value of P tot is approximately 122.3 kg/day of these two sources. There are also two outflows - drainage of cleaned water to the recipient - the river Nitra - 9.9 kg Ptot/day and Ptot content in sewage sludge - about 120.3 kg Ptot/day - total 130.2 kg Ptot/day.

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