Treatment of wastewaters from a formaldehyde-urea adhesives factory

2000 ◽  
Vol 42 (5-6) ◽  
pp. 293-300 ◽  
Author(s):  
J.M. Garrido ◽  
R. Méndez ◽  
J.M. Lema
Keyword(s):  
Activated Sludge ◽  
Organic Nitrogen ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Organic Matter Content ◽  
Matter Content ◽  
Organic Loading Rate ◽  
Nitrogen Gas ◽  
Laboratory Unit ◽  
Formaldehyde Removal

Wastewater from a formaldehyde-urea adhesives factory is characterised by a high organic matter content (COD between 460 and 3900 mg/L mostly due to formaldehyde 220–4000 mg/L) and organic nitrogen (TKN 110–805 mg/L). Besides, a fraction of COD is given by a formaldehyde-urea polymer with a relatively high molecular weight. In a lab-scale (2 L) activated sludge unit, a high formaldehyde removal (higher than 99%) was obtained while the total COD and TKN removal ranged between 70–85 % and 30–50%, respectively. Formaldehyde was used by microorganisms as carbon source and also for the conversion of nitrate to nitrogen gas. The Organic Loading Rate (OLR) was between 0.2 and 1.2 kg–COD/m3·d and the Hydraulic Retention Time (HRT) between 0.5 and 1.4 d. The non degraded TKN and COD, mostly corresponding to the polymeric fraction, was further treated in an ozonation unit, which increased very efficiently the bioavailability of TKN towards nitrification and allowed an additional COD removal. Results from lab-scale reactors were used for designing and operating an industrial scale activated sludge unit, being the efficiency attained at full-scale similar to the laboratory unit.

scholarly journals Influence of hydraulic and organic load on the anaerobic-aerobic dairy wastewater treatment characteristics

2021 ◽  
Vol 247 ◽  
pp. 01002
Author(s):  
Rustem Khabibullin ◽  
Thao Le Huong ◽  
Andrey Petrov
Keyword(s):  
Dilution Rate ◽  
Loading Rate ◽  
Organic Matter Content ◽  
Spatial Separation ◽  
Matter Content ◽  
Dairy Wastewater ◽  
Organic Load ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Treatment Efficiency

The performance of the anaerobic-aerobic sequencing labscale reactors for the treatment of a milk processing wastewater was studied. The wastewater flow rate was varied from 78.0 to 149.0 ml•h-1 and organic matter content from 3.8 to 6.8 g COD∙dm-3. This corresponded to the change of dilution rate from 0.4 to 0.8 day-1 and organic loading rate from 1.4 to 2.8 g COD•dm-3•day-1. An increase of hydraulic load reduced the treatment efficiency at the first anaerobic stage from 44.4 to 29.7%, but it was compensated at the aerobic treatment stage. Increasing the organic loading rate improved the treatment efficiency at the anaerobic stage from 44.4 to 54.2%. It was shown that spatial separation of anaerobic stage onto two phases increases the treatment efficiency in anaerobic stage and in whole (85.8 and 98.7%) in comparison to non-separation mode (45.5 and 73.9%, respectively). The correlation analysis of the organic loading rate L, organic consumption rate P and dilution rate D on the treatment efficiency E allowed to obtain the equations can be used for mathematical optimization of the process.

Properties of Anaerobic Activated Sludge in Biohydrogen Production Reactor

2014 ◽  
Vol 884-885 ◽  
pp. 503-506
Author(s):  
Zhi Qin ◽  
Guang Yu Bai ◽  
Qi Zhang ◽  
Yong Yan Cui ◽  
Chao Yu Zhang
Keyword(s):  
Hydrogen Production ◽  
Activated Sludge ◽  
Retention Time ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Biohydrogen Production ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Mixture Volume ◽  
Total Mixture

For the properties of activated sludge studies, three kinds of activated sludge were obtained from continuous hydrogen production reactor. Activated sludge was got under organic loading rate (OLR) of 3, 7 and 25 kgCOD/m3·d condition, respectively. Sedimentation performance and activities of sludge were investigated. When OLR was 3 kgCOD/m3·d, activated sludge showed good sedimentation performance. After 30 minutes sedimentation, the volume of activated sludge in total mixture volume was about 39%. When OLR was 7 and 25kgCOD/m3·d, after 30 minutes sedimentation, the volume of activated sludge in total mixture volume was 80% and 83%, respectively. The increase of biomass is the main reason for increase of sedimentation performance. MLVSS/MLSS of activated sludge was 37.7% and 79.6% under OLR of 3 and 25kgCOD/m3·d condition, therefore, activities of activated sludge was high under high OLR condition. Since sedimentation performance of sludge is high under high OLR condition, hydraulic retention time should controlled carefully in engineering operation.

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

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.

Working Parameters Optimization of Hydrolysis-acidogenesis reactor in two stage anaerobic digestion of slaughterhouse Wastewater for Biogas Production

2020 ◽  
Author(s):  
Dejene Tsegaye Bedane ◽  
Mohammed Mazharuddin Khan ◽  
Seyoum Leta Asfaw
Keyword(s):  
Anaerobic Digestion ◽  
Working Conditions ◽  
Retention Time ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Oxygen Demand ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Slaughterhouse Wastewater ◽  
Working Parameters

Abstract Background : Wastewater from agro-industries such as slaughterhouse is typical organic wastewater with high value of biochemical oxygen demand, chemical oxygen demand, biological organic nutrients (Nitrogen and phosphate) which are insoluble, slowly biodegradable solids, pathogenic and non-pathogenic bacteria and viruses, parasite eggs. Moreover it contains high protein and putrefies fast leading to environmental pollution problem. This indicates that slaughterhouses are among the most environmental polluting agro-industries. Anaerobic digestion is a sequence of metabolic steps involving consortiums of several microbial populations to form a complex metabolic interaction network resulting in the conversation of organic matter into methane (CH 4 ), carbon dioxide (CO 2 ) and other trace compounds. Separation of the phase permits the optimization of the organic loading rate and HRT based on the requirements of the microbial consortiums of each phase. The purpose of this study was to optimize the working conditions for the hydrolytic - acidogenic stage in two step/phase anaerobic digestion of slaughterhouse wastewater. The setup of the laboratory scale reactor was established at Center for Environmental Science, College of Natural Science with a total volume of 40 liter (36 liter working volume and 4 liter gas space). The working parameters for hydrolytic - acidogenic stage were optimized for six hydraulic retention time 1-6 days and equivalent organic loading rate of 5366.43 – 894.41 mg COD/L day to evaluate the effect of the working parameters on the performance of hydrolytic – acidogenic reactor. Result : The finding revealed that hydraulic retention time of 3 day with organic loading rate of 1,788.81 mg COD/L day was a as an optimal working conditions for the parameters under study for the hydrolytic - acidogenic stage. The degree of hydrolysis and acidification were mainly influenced by lower hydraulic retention time (higher organic loading rate) and highest values recorded were 63.92 % at hydraulic retention time of 3 day and 53.26% at hydraulic retention time of 2 day respectively. Conclusion : The finding of the present study indicated that at steady state the concentration of soluble chemical oxygen demand and total volatile fatty acids increase as hydraulic retention time decreased or organic loading rate increased from 1 day hydraulic retention time to 3 day hydraulic retention time and decreases as hydraulic retention time increase from 4 to 6 day. The lowest concentration of NH 4 + -N and highest degree of acidification was also achieved at hydraulic retention time of 3 day. Therefore, it can be concluded that hydraulic retention time of 3 day/organic loading rate of 1,788.81 mg COD/L .day was selected as an optimal working condition for the high performance and stability during the two stage anaerobic digestion of slaughterhouse wastewater for the hydrolytic-acidogenic stage under mesophilic temperature range selected (37.5℃). Keywords : Slaughterhouse Wastewater, Hydrolytic – Acidogenic, Two Phase Anaerobic Digestion, Optimal Condition, Agro-processing wastewater

Anaerobic treatment of a medium strength industrial wastewater at low-temperature and short hydraulic retention time: a pilot-scale experience

2011 ◽  
Vol 64 (8) ◽  
pp. 1629-1635 ◽  
Author(s):  
M. Esparza Soto ◽  
C. Solís Morelos ◽  
J. J. Hernández Torres
Keyword(s):  
Low Temperature ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Pilot Scale ◽  
Anaerobic Treatment ◽  
Uasb Reactor ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Processing Industry ◽  
Industry Wastewater

The aim of this work was to evaluate the performance of a pilot-scale upflow anaerobic sludge blanket (UASB) reactor during the treatment of cereal-processing industry wastewater under low-temperature conditions (17 °C) for more than 300 days. The applied organic loading rate (OLRappl) was gradually increased from 4 to 6 and 8 kg CODsol/m3d by increasing the influent soluble chemical oxygen demand (CODsol), while keeping the hydraulic retention time constant (5.2 h). The removal efficiency was high (82 to 92%) and slightly decreased after increasing the influent CODsol and the OLRappl. The highest removed organic loading rate (OLRrem) was reached when the UASB reactor was operated at 8 kg CODsol/m3d and it was two times higher than that obtained for an OLRappl of 4 kg CODsol/m3d. Some disturbances were observed during the experimentation. The formation of biogas pockets in the sludge bed significantly complicated the biogas production quantification, but did not affect the reactor performance. The volatile fatty acids in the effluent were low, but increased as the OLRappl increased, which caused an increment of the effluent CODsol. Anaerobic treatment at low temperature was a good option for the biological pre-treatment of cereal processing industry wastewater.

Impact of Hydraulic Retention Time at Constant Organic Loading Rate in a Two-Stage Expanded Granular Sludge Bed Reactor

2014 ◽  
Vol 31 (6) ◽  
pp. 317-323 ◽  
Author(s):  
Mahyar Ghorbanian ◽  
Robert M. Lupitskyy ◽  
Jagannadh V. Satyavolu ◽  
R. Eric Berson
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Loading Rate ◽  
Granular Sludge ◽  
Organic Loading Rate ◽  
Organic Loading ◽  
Two Stage
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