Complete decomposition of biological waste sludge by thermophilic aerobic bacteria

2000 ◽  
Vol 42 (9) ◽  
pp. 81-88 ◽  
Author(s):  
Y. Sakai ◽  
T. Aoyagi ◽  
N. Shiota ◽  
A. Akashi ◽  
S. Hasegawa
Keyword(s):  
High Efficiency ◽  
Municipal Sewage ◽  
Aerobic Bacteria ◽  
Municipal Sewage Sludge ◽  
Aeration Tank ◽  
Petrochemical Plant ◽  
Bacillus Sp ◽  
Excess Sludge ◽  
Complete Decomposition ◽  
New Process

Conventional activated sludge (AS) process is an economical and effective biooxidation process although a large amount of excess sludge is necessarily generated. We have developed a new zero-discharge AS process, in which no excess sludge is generated. It was formed by combining the conventional AS process with thermophilic aerobic sludge digester in which excess sludge is solubilized by thermophilic enzyme, so we call it hereafter the digester S-TE reactor. The excess sludge withdrawn from the AS step is subjected to the S-TE reactor, followed by its circulation to an aeration tank. Complete decomposition of the excess sludge is carried out when the sludge is solubilized by thermophilic aerobic bacteria (e.g. Bacillus sp.) and mineralized by mesophilic bacteria. The S-TE reactor is operated at 65°C with hydraulic retention time of 1 day. Bench-scale test facilities of both the new process and conventional AS process were comparatively operated under the conditions of BOD-SS loading of 0.3 kg/kg/dand MLSS of 2,000 mg/L using artificial wastewater for over 100 days. The S-TE reactor was initially inoculated with the seedling culture of isolated Bacillus sp. bacteria. No additional inoculation seem to be needed under the steady condition since these bacteria can form spores and survive even under mesophilic conditions. The average rates of VSS solubilization and VM removal in the S-TE reactor were 40% and 15%, respectively. No excess sludge was generated when 3-fold amounts of the excess sludge generated in the conventional AS process were subjected to the S-TE reactor. In the new process, BOD was removed with high efficiency. Slight increase of SS and TOC was observed when compared with those of the AS process. A pilot-scale facility of the process has been operated with a petrochemical plant wastewater for a year. MLSS concentration was continuously kept around 3,000 mg/L without withdrawing the excess sludge. Inorganic salts seemed not to accumulate in the process. Therefore, it was demonstrated that excess sludge generation was completely reduced in the new process. According to our estimates, total operating costs for the new process are reduced to 40-50% of those of the conventional wastewater dewatering process. An application to a municipal sewage sludge treatment is currently performed in its full-scale facility.

A strategy in wastewater treatment process for significant reduction of excess sludge production

2002 ◽  
Vol 45 (12) ◽  
pp. 127-134 ◽  
Author(s):  
N. Shiota ◽  
A. Akashi ◽  
S. Hasegawa
Keyword(s):  
Wastewater Treatment ◽  
Treatment Process ◽  
Pilot Scale ◽  
Aeration Tank ◽  
Excess Sludge ◽  
Wastewater Treatment Process ◽  
Conventional Activated Sludge ◽  
New Process ◽  
Treatment Step ◽  
Sludge Production

A novel wastewater treatment process (S-TE PROCESS®) with significantly reduced production of excess sludge has been developed. The process consists of two different stages, one for a biological wastewater treatment and the other for a thermophilic aerobic digestion of the resulting sludge. A portion of return sludge from the wastewater treatment step is injected into a thermophilic aerobic sludge digester (TASD), in which the injected sludge is solubilized by the action of thermophilic aerobic bacteria. The solubilized sludge is returned to the aeration tank in the wastewater treatment step for its further degradation. Pilot-scale facilities of the S-TE process and the conventional activated sludge process as a control, both treating the same industrial wastewater, were comparatively operated for totally 270 days. As a result, 93% reduction in overall excess sludge production was achieved in the S-TE operation. The SS solubilization rate in TASD was stable at around 30%. Only a slight increase in the effluent SS and TOC concentrations was observed compared with those of the control facility. Otherwise the removal efficiency of TOC was approximately 95% for both plants. A full-scale plant treating domestic sewage was operated for three years, showing 75% reduction of overall excess sludge production. It was concluded that the new process was feasible.

Treatment of easily biodegradable wastewater avoiding bulking sludge

2002 ◽  
Vol 46 (1-2) ◽  
pp. 503-506 ◽  
Author(s):  
N. Matsché ◽  
S. Winkler ◽  
L. Prendl ◽  
K. Dornhofer ◽  
G. Wandl
Keyword(s):  
Treatment Plant ◽  
Gas Production ◽  
Aeration Tank ◽  
Biodegradable Material ◽  
Excess Sludge ◽  
Food Industries ◽  
Biological Sludge ◽  
New Process ◽  
One Year ◽  
Treatment Alternatives

The presence of easily degradable compounds from food industries frequently leads to bulking problems. The paper describes a new process that has been developed for a dairy in Austria. Because of the increase in production the treatment plant receiving the wastewater up to now was not able to handle the increased loads. Therefore detailed studies for treatment alternatives have been undertaken which led to a completely new concept. The excess sludge of the urban treatment plant is contacted with the concentrated dairy waste in a separate contact tank. In this tank the easily degradable substrate from the industrial waste is mainly adsorbed to the biological sludge and after a mechanical dewatering transferred to the anaerobic digester where it yields an increased gas production. The filtrate of the dewatering process is completely free from biodegradable material and can without danger of bulking be fed to the aeration tank. The process has been in operation for more than one year and has fulfilled all expectations.

A New Process to Treat Strong Biological Waste

1993 ◽  
Vol 27 (1) ◽  
pp. 213-218 ◽  
Author(s):  
D. P. Henry ◽  
R. H. Thomson
Keyword(s):  
Organic Acids ◽  
Residence Time ◽  
Filamentous Fungus ◽  
Treatment Time ◽  
Aerobic Bacteria ◽  
Bacillus Sp ◽  
Candida Sp ◽  
New Process ◽  
Corynebacterium Sp ◽  
Nylon Cloth

Strong brewery waste was trickled through a vertical curtain consisting of two 3mm layers of reticulated Polyurethane foam bonded to a reinforcing nylon cloth core. A filamentous fungus, Geotrichum fragrans adhered to the curtain and provided a matrix for other yeasts and aerobic bacteria which include Kloeckera lindneri and a Candida sp., a Bacillus sp. and a Corynebacterium sp. The organisms grew as a lawn. To avoid anaerobiosis the lawn was harvested periodically by passing the curtain through rollers leaving a viable representative residue of the population. Passage through 6m of curtain reduced a TOD of 55,000 mgL−1 to 3,300 mgL−1 (94%). Probably the length of the curtain could be reduced to 4m with a residence time of 9.6h. One m2 of curtain with a 4m fall can treat 15Ld−1. A further waste from pigs (2% solids) was acidogenically fermented to produce organic acids. The acids during clarification were used to kill the bacterial pathogens in the waste. The liquor was run through a curtain inoculated with suitable organisms. These removed the unpleasant odour and 88% of the TOD in a 4m passage through the curtain. Treatment time: fermentation 5d, clarification and removal of pathogens 2d, treatment in curtain 0.3d, total 7.3d.

scholarly journals The Comparison of Selected Types of Municipal Sewage Sludge Filtrates Toxicity in Different Biological Models: From Bacterial Strains to Mammalian Cells. Preliminary Study

Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2353 ◽  
Author(s):  
Agata Jabłońska-Trypuć ◽  
Urszula Wydro ◽  
Lluis Serra-Majem ◽  
Andrzej Butarewicz ◽  
Elżbieta Wołejko
Keyword(s):  
Sewage Sludge ◽  
Cell Line ◽  
Mammalian Cells ◽  
Complex Mixture ◽  
Human Cell Line ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
Aeration Tank ◽  
Biological Models ◽  
Bacterial Strains

Sewage sludge (SS) is a complex mixture of potentially toxic compounds, which may affect the environment. Many methodologies are being implemented in order to assess the risk that SS may cause after the exposition, but usually they rely on chemical analyses that cannot predict their toxicological impact. Therefore, biological systems are essential in such studies. The aim of this study was to estimate the effect of 3 types of SS filtrates: sludge from primary clarifier, sludge from aeration tank and sludge from thickened sludge tank after flocculant addition. In order to thoroughly investigate SS cytotoxicity, we proposed different biological models: Aliivibrio fischeri, Escherichia coli, Candida albicans and LN-229 glioblastoma cell line. Obtained results indicate that SS3 was the most toxic against A. fisheri, but tests conducted with the use of E. coli and LN-229 human cell line showed the higher toxicity of SS1. Different toxicity of analyzed filtrates in different biological models could be explained by differences in applied model structure, metabolism and life requirements. Therefore, the reuse of SS should be conducted with caution, and it is important for the SS to undergo a specific remediation process before introducing them into the environment.

An innovative approach to reduce excess sludge production in the activated sludge process

1994 ◽  
Vol 30 (9) ◽  
pp. 11-20 ◽  
Author(s):  
H. Yasui ◽  
M. Shibata
Keyword(s):  
Activated Sludge ◽  
Biomass Concentration ◽  
Experimental Period ◽  
Aeration Tank ◽  
Activated Sludge Process ◽  
Biological Degradation ◽  
Excess Sludge ◽  
Conventional Activated Sludge ◽  
New Process ◽  
Sludge Production

A new process has been developed to reduce excess sludge production, in which both excess sludge digestion and wastewater treatment are conducted simultaneously in the same aeration tank. The ozonation enhances biological degradation of the activated sludge, which is decomposed in a subsequent biological treatment. A considerable amount of biomass is mineralized biologically in proportion to the amount of recirculated biomass from the ozonation stage to the biological stage. It was observed that the amount of excess sludge is reduced to nearly zero when 1.2 kg/m3-aeration tank volume of biomass is recirculated in a day from the biological stage to the ozonation stage at a BOD loading of 1.0 kg/m3/d. A biomass concentration of 4200 mg/L was maintained at 1.0 kg-BOD/m3/d without drawing excess sludge for 6 weeks of experimental period under ozone dose of 0.05 g-O3/g-SS and recirculation rate at 0.3 d−1. Only a limited difference in the effluent quality was observed between the new process and the conventional activated sludge process.

A long-term chemical and infrared spectroscopy study on a soil amended with municipal sewage sludge

Agronomie ◽  
2001 ◽  
Vol 21 (2) ◽  
pp. 169-178 ◽  
Author(s):  
Giovanni Gigliotti ◽  
Pier Lodovico Giusquiani ◽  
Daniela Businelli
Keyword(s):  
Infrared Spectroscopy ◽  
Sewage Sludge ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
Spectroscopy Study

scholarly journals Long-term field fertilization experiment with energy willow (Salix sp.) − Elemental composition and chlorophyll fluorescence in the leaves

2018 ◽  
Vol 67 (1) ◽  
pp. 91-103
Author(s):  
László Simon ◽  
Marianna Makádi ◽  
György Vincze ◽  
Zsuzsanna Uri ◽  
Katalin Irinyiné Oláh ◽  
...  
Keyword(s):  
Chlorophyll Fluorescence ◽  
Energy Crop ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
Fertilization Experiment ◽  
Nitrogen Concentrations ◽  
Set Up ◽  
Leaf Chlorophyll Fluorescence ◽  
Term Field

A small-plot long-term field fertilization experiment was set up in 2011 with willow (Salix triandra x Salix viminalis ’Inger’) grown as an energy crop in Nyíregyháza, Hungary. The brown forest soil was treated three times (in June 2011, May 2013, May 2016) with municipal biocompost (MBC), municipal sewage sludge compost (MSSC) or willow ash (WA), and twice (June 2011, May 2013) with rhyolite tuff (RT). In late May – early June 2016 urea (U) and sulphuric urea (SU) fertilizers were also applied to the soil as top-dressing (TD). These fertilizers and amendments were also applied to the soil in 2016 in the combinations; MBC+SU, RT+SU, WA+SU and MSSC+WA. All the treatments were repeated four times. In July 2016 the highest nitrogen concentrations in willow leaves were measured in the U (3.47 m/m%) and SU (3.01 m/m%) treatments, and these values were significantly higher than the control (2.46 m/m%). An excess of nitrogen considerably reduced the Zn uptake of the leaves, with values of 39.5 μg g-1 in the U treatment, 53.4 μg g-1 in the SU treatment, and 63.5 μg g-1 in the control. All other amendments or TDs, except for WA, enhanced the specific potassium concentrations in willow leaves compared to the control. No significant quantities of toxic elements (As, Ba, Cd, Pb) were transported from soil amendments or TDs to the willow leaves. In July 2016 the most intensive leaf chlorophyll fluorescence was observed in the MSSC and MSSC+WA treatments.

scholarly journals Highly Effective Adsorption Process of Ni(II) Ions with the Use of Sewage Sludge Fly Ash Generated by Circulating Fluidized Bed Combustion (CFBC) Technology

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3106
Author(s):  
Tomasz Kalak ◽  
Kinga Marciszewicz ◽  
Joanna Piepiórka-Stepuk
Keyword(s):  
Fly Ash ◽  
Sewage Sludge ◽  
Fluidized Bed ◽  
Circulating Fluidized Bed ◽  
Municipal Sewage ◽  
Municipal Sewage Sludge ◽  
Fluidized Bed Combustion ◽  
Nickel Ions ◽  
Suitable Material ◽  
Circulating Fluidized Bed Combustion

Recently, more and more attention has been paid to the removal of nickel ions due to their negative effects on the environment and human health. In this research, fly ash obtained as a result of incineration of municipal sewage sludge with the use of circulating fluidized bed combustion (CFBC) technology was used to analyze the possibility of removing Ni(II) ions in adsorption processes. The properties of the material were determined using analytical methods, such as SEM-EDS, XRD, BET, BJH, thermogravimetry, zeta potential, SEM, and FT-IR. Several factors were analyzed, such as adsorbent dose, initial pH, initial concentration, and contact time. As a result of the conducted research, the maximum sorption efficiency was obtained at the level of 99.9%. The kinetics analysis and isotherms showed that the pseudo-second order equation model and the Freundlich isotherm model best suited this process. In conclusion, sewage sludge fly ash may be a suitable material for the effective removal of nickel from wastewater and the improvement of water quality. This research is in line with current trends in the concepts of circular economy and sustainable development.

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