Comparison of different mixing phenomena in anaerobic digestion using food waste and sewage treatment plant for green biofuel through simulations of velocity contours

Effects of a thermochemical pretreatment on the anaerobic digestion of waste activated sludge (WAS) was investigated by semicontinuously-fed digesters operated at 37¡C. WAS from a return sludge line of a municipal sewage treatment plant was pretreated by autoclaving at 130°C for 5 minutes after adding 0.3g NaOH/g VSS. Solids of WAS were thermochemically solubilized to one half and then 60% or more were in totality solubilized in anaerobic digesters fed with pretreated WAS at 2-8 days of hydraulic retention times (HRT), while only 16-36% were solubilized in digesters fed with raw WAS. The adverse effect of the set temperature (130°C) on the biodegradability of protein was not found. As a result, removal rates of COD in digestion was increased from 38% to 57% at 8 days HRT by the pretreatment. A specific methane production rate in the pretreated process was three times as high as the normal process. The thermochemical pretreatment was found to be very effective to enhance biodegradability as well as solubilization of WAS in anaerobic digestion.

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The Effect of Biology Activity on WS during Anaerobic Digestion

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.194-196.790 ◽

2011 ◽

Vol 194-196 ◽

pp. 790-793

Author(s):

Dong Su Bi ◽

Xiao Pin Guo

Keyword(s):

Anaerobic Digestion ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Release Mechanism ◽

Paper Sludge ◽

Waste Sludge ◽

In The Beginning

The effect of biology activity on liquid indicators (pH, SCOD, VSS ,SOP etc.) and solid indicators (PHA , hepatin, TP etc.) of phosphorus-rich waste sludge during the anaerobic digestion were studied in this paper. Sludge used in this study was obtained from a sewage treatment plant in which the A/O process was used. The results indicated that the hydrolyzing of waste sludge was promoted by the addition of bacterium inhibitor in the beginning of experiment. However, the presence of bacterium inhibitor was disadvantage to both hydrolyzed and biological release mechanism of phosphorus in anaerobic digestion system.

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Polyhydroxyalkanoate (PHA) production from waste

Water Science & Technology ◽

10.2166/wst.2003.0472 ◽

2003 ◽

Vol 48 (8) ◽

pp. 221-228 ◽

Cited By ~ 58

Author(s):

D.H. Rhu ◽

W.H. Lee ◽

J.Y. Kim ◽

E. Choi

Keyword(s):

Food Waste ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Fermented Food ◽

Biological Nutrient Removal ◽

Economical Analysis ◽

P Limitation ◽

Alternative Material ◽

Maximum Content

PHA (polyhydroxyalkanoate) production was attempted with SBRs from food waste. Seed microbes were collected from a sewage treatment plant with a biological nutrient removal process, and acclimated with synthetic substrate prior to the application of the fermented food waste. Laboratory SBRs were used to produce PHA with limited oxygen and nutrients. The maximum content of 51% PHA was obtained with an anaerobic/aerobic cycle with P limitation, and the yield was estimated to be about 0.05 gPHAproduced/gCODapplied or 25 kg PHA/dry ton of food waste, assuming more than 40% of the PHA contents were recoverable. PHB/PHA ratios were 0.74 to 0.77 due to the higher acetate concentrations. Economical analysis seemed to suggest the PHA produced from the food waste could be an alternative material to produce the biodegradable plastic to be used for the collection bags for solid waste.

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Biogas production from food waste codigested with sewage treatment plant sludge using biochemical methane potential method

International Journal of Environment and Sustainable Development ◽

10.1504/ijesd.2016.077403 ◽

2016 ◽

Vol 15 (3) ◽

pp. 300 ◽

Cited By ~ 1

Author(s):

S. Padmavathi ◽

K. Latha ◽

D. Nilavunesan ◽

P. Baskaralingam ◽

S. Sivanesan

Keyword(s):

Food Waste ◽

Biogas Production ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Potential Method ◽

Biochemical Methane Potential ◽

Methane Potential

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Experimental Study on Anaerobic Digestion of Remaining Sludge in Municipal Wastewater Treatment Plant

Journal of Architectural Research and Development ◽

10.26689/jard.v2i4.421 ◽

2018 ◽

Vol 2 (4) ◽

Author(s):

Jia Li ◽

Hong Yang

Keyword(s):

Anaerobic Digestion ◽

Environmental Protection ◽

Municipal Wastewater ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Optimal Operation ◽

Plant Management ◽

Municipal Wastewater Treatment ◽

Excess Sludge

Along with the development and progress of environmental protection management, it is necessary to pay full attention to the disposal of excess sludge in the process of urban sewage treatment plant management. Ensure effective integration of management mechanisms and management paths. To a certain extent, it can improve the actual efficiency of digestion and treatment work and lay a foundation for the optimal operation of environmental protection management. In this paper, the treatment of excess sludge in a sewage treatment plant is studied. The method and results of anaerobic digestion test of excess sludge in a sewage treatment plant are discussed for reference only.

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Life Cycle Assessment of an intensive sewage treatment plant in Barcelona (Spain) with focus on energy aspects

Water Science & Technology ◽

10.2166/wst.2011.522 ◽

2011 ◽

Vol 64 (2) ◽

pp. 440-447 ◽

Cited By ~ 26

Author(s):

L. Bravo ◽

I. Ferrer

Keyword(s):

Life Cycle Assessment ◽

Life Cycle ◽

Anaerobic Digestion ◽

Environmental Impacts ◽

Biogas Production ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Pre Treatment ◽

Energy Aspects

Life Cycle Assessment was used to evaluate environmental impacts associated to a full-scale wastewater treatment plant (WWTP) in Barcelona Metropolitan Area, with a treatment capacity of 2 million population equivalent, focussing on energy aspects and resources consumption. The wastewater line includes conventional pre-treatment, primary settler, activated sludge with nitrogen removal, and tertiary treatment; and the sludge line consists of thickening, anaerobic digestion, cogeneration, dewatering and thermal drying. Real site data were preferably included in the inventory. Environmental impacts of the resulting impact categories were determined by the CLM 2 baseline method. According to the results, the combustion of natural gas in the cogeneration engine is responsible for the main impact on Climate Change and Depletion of Abiotic Resources, while the combustion of biogas in the cogeneration unit accounts for a minor part. The results suggest that the environmental performance of the WWTP would be enhanced by increasing biogas production through improved anaerobic digestion of sewage sludge.

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Effect of Sawdust and Grass Clippings as Bulking Materials on the Quality of Compost

International Journal of Irrigation and Agricultural Development (IJIRAD) ◽

10.47762/2018.964x.35 ◽

2018 ◽

Vol 2 (1) ◽

Author(s):

K. Prempeh ◽

B. Fei- Baffoe ◽

B. W. Lawson

Keyword(s):

Organic Matter ◽

Food Waste ◽

Science And Technology ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Daily Basis ◽

Kwame Nkrumah ◽

Organic Matter Loss

The increase in student population has led to a corresponding increase in the generation of waste on the Campus of the Kwame Nkrumah University of Science and Technology. Composting of the biodegradable portion of waste is seen as a better option to reduce the volume of waste and manage it at the same time. This study hence aimed to investigate the effect of some bulking materials on the quality of compost after the decomposition of the biodegradable portion of the waste generated. Bin composting was employed for this analysis. Composting was conducted over a 60 -day period at the sewage treatment plant on the KNUST Campus. Wastes comprising of food waste, sawdust, and grass clippings were mixed in ratios of 1:1, 1:2, and 2:1 (v/v) ratio for sawdust/food waste (SSD 1:1, SSD 1:2, SSD 2:1) and grass clipping/food waste (SGC 1:1, SGC 1:2, SGC 2:1). Turning of compost was done manually at three days interval during which the volume was also recorded. Temperatures were taken on daily basis, three times within a day at 8 am, 12 pm and 4 pm respectively. Volume of all bins reduced as percentage organic matter decreased leading to an increase in percentage ash to between 39. % and 64.5 %. Percent organic matter loss was highest in the grass clipping/food waste treatments compared to the sawdust/food waste treatments. By the end of eight weeks of analysis, the grass clipping/food (SGC 1:1, SGC 1:2, and SGC 2:1) waste formulations were seen to decompose faster than the sawdust/food (SSD 1:1, SSD 1:2, and SSD 2:1) waste formulation. The grass clipping/food waste ratios (especially the SGC 2:1) therefore gave better compost in terms of the quality since rate of decomposition was faster compared to the sawdust/food waste.

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A Feasibility Study on Effect of Food Waste Leachate Additions in the Full-Scale Waste Leachate Treatment Facility after the African Swine Fever Outbreak in South Korea

Energies ◽

10.3390/en14238045 ◽

2021 ◽

Vol 14 (23) ◽

pp. 8045

Author(s):

Pul-Eip Lee ◽

Won-Bae Lee ◽

Heesung Moon ◽

Junhwa Kwon ◽

Hueon Namkung ◽

...

Keyword(s):

Organic Matter ◽

Food Waste ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

African Swine Fever ◽

Treatment Method ◽

Gas Production ◽

Food Waste Leachate ◽

Waste Leachate

Due to the ban on the use of food waste as wet swine feed after the outbreak of African swine fever (ASF), 2900 tons/day of food waste and 1083 tons/day of food waste leachate were additionally generated. As an alternative treatment method for food waste leachate, the input of food waste leachate on weekends (5% of food waste leachate inflow, 100 tons/day) and its increased input (merge ratio 21.7%, 227.01 tons/day → 27.8%, 453.71 tons/day) into the digesters operated in a public sewage treatment plant were investigated. Additionally, the feasibility of the method was evaluated by analyzing the operation parameters, evaluating the operation efficiency, and identifying other environmental effects on the sewage treatment plant. In the case of input on weekends, the organic matter decomposition rate and gas production rate decreased by 8.0% and 9.5%, respectively, although the input on weekends was judged to be feasible, considering that the inflow into the WWTP increased by up to 206% due to the long-term (7 weeks) monsoon. In the case of the increased input of food waste leachate, the organic matter decomposition and gas production rates increased by 2.5% and 4.8%, respectively, compared with before the increased input. The results of this study confirmed that the additional input of food waste leachate into existing biogasification facilities is feasible. When performed in a stable manner, the use of food waste for anaerobic digestion is considered an appropriate alternative treatment method to wet feed. This will lead to technological and industrial development.

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