Modeling of multimode anaerobic/anoxic/aerobic wastewater treatment process at low temperature for process optimization

Zhou, Zhen; Shen, Xuelian; Jiang, Lu-Man; Wu, Zhengzheng; Wang, Zhiwei; Ren, Weichao; Hu, Dalong

doi:10.1016/j.cej.2015.07.017

Cited by 34 publications

(13 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In order to further remove nitrogen and phosphorus from the wastewater, the new process such as anaerobic/anoxic/oxic (AAO) process had to be added in traditional activated sludge process [57]. However, the control of combined systems was usually complicated, and additional treatment units had to be added, which were mentioned above.…”

Section: Resultsmentioning

confidence: 99%

Molasses wastewater treatment and lipid production at low temperature conditions by a microalgal mutant Scenedesmus sp. Z-4

Wen

Xing

et al. 2017

Biotechnol Biofuels

106

View full text Add to dashboard Cite

BackgroundSimultaneous wastewater treatment and lipid production by oleaginous microalgae show great potential to alleviate energy shortage and environmental pollution, because they exhibit tremendous advantages over traditional activated sludge. Currently, most research on wastewater treatment by microalgal are carried out at optimized temperature conditions (25–35 °C), but no information about simultaneous wastewater treatment and lipid production by microalgae at low temperatures has been reported. Microalgal growth and metabolism will be inhibited at low temperature conditions, and satisfactory wastewater treatment performance will be not obtained. Therefore, it is critical to domesticate and screen superior microalgal strains with low temperature adaptability, which is of great importance for wastewater treatment and biodiesel production.ResultsIn this work, simultaneous wastewater treatment and lipid production were achieved by a microalgal mutant Scenedesmus sp. Z-4 at the low temperature conditions (4, 10, and 15 °C). The results showed that algal growth was inhibited at 4, 10, and 15 °C compared to that at the optimal temperature of 25 °C. However, decreased temperature had no significant effect on the total cellular lipid content of algae. Importantly, lipid productivity at 10 °C was compromised by more net energy output relevant to biodiesel production, which demonstrated that the low temperature of 10 °C was favorable to wastewater treatment and energy recovery by Scenedesmus sp. Z-4. When molasses wastewater with optimal COD concentration of 8000 mg L−1, initial inoculation ratio of 15%, and C/N ratio of 15 was used to cultivate microalgae, the maximum removal rate of COD, TN, and TP at 10 °C reached 87.2, 90.5, and 88.6%, respectively. In addition, lipid content of 28.9% and lipid productivity of 94.4 mg L−1 day−1 were obtained.Conclusions Scenedesmus sp. Z-4 had good adaptability to low temperature conditions, and showed great potential to realize simultaneous wastewater treatment and lipid production at low temperatures. The proposed approach in the study was simple compared to other wastewater treatment methods, and this potential novel process was still efficient to remove COD, N, and P at low temperatures. Thus, it had a vital significance for the wastewater treatment in low temperature regions.Electronic supplementary materialThe online version of this article (doi:10.1186/s13068-017-0797-x) contains supplementary material, which is available to authorized users.

show abstract

Section: Resultsmentioning

confidence: 99%

Molasses wastewater treatment and lipid production at low temperature conditions by a microalgal mutant Scenedesmus sp. Z-4

Wen

Xing

et al. 2017

Biotechnol Biofuels

106

View full text Add to dashboard Cite

show abstract

“…The AE was obtained as 4.42 kWh/d which was lower than previous finding (Zhou et al . ), which could be due to the different bioreactor configuration. The cost of aerated wastewater was measured as 0.3 €/m 3 that was in accordance with the literature findings (Gil et al .…”

Section: Resultsmentioning

confidence: 99%

“…The results showed that the operational cost of our system was much lower (0.556 €/d) than that seen in the previous investigation (Zhou et al . ; Vivekanandan et al . ).…”

Section: Resultsmentioning

confidence: 99%

“…The quantity of cost performance index was determined by the following equation (Zhou et al . ):

normalC normalP normalI = α_{normalE normalQ} normalE normalQ + α_{normalA normalE} normalA normalE + α_{normalM normalE} normalM normalE + α_{normalP normalE} normalP normalE + α_{normalS normalP} normalS normalP

…”

Section: Methodsmentioning

confidence: 99%

“…The pollutant unit (PU, mg/l) was measured by four main parameters such as COD, TSS, TN and PO 32 4 -P through the component concentration and weighting factor (b) recommended by the Chinese EPA (b TSS 5 0.25, b COD 5 1, b TN 5 20, and b TP 5 20). The quantity of cost performance index was determined by the following equation (Zhou et al 2015):…”

Section: Cost Evaluationmentioning

confidence: 99%

See 2 more Smart Citations

Modeling the kinetics and cost performance index of high rate up‐flow anaerobic, anoxic, oxic bioreactor for meat wastewater treatment

Abyar

Younesi

Bahramifar

et al. 2018

Water & Environment J

View full text Add to dashboard Cite

The simultaneous biological removal of COD, TN and phosphorus from meat industrial wastewater (MIW) using a lab‐scale high rate up‐flow anaerobic–anoxic–oxic bioreactor (A2O bioreactor) was investigated. The bioreactor was operated at different HRT, COD/TN ratio and aerated volume fractions to monitor the COD and nutrient removal efficiency. The maximum COD removal rate was detected at HRT of 5 h and COD/TN ratio of 100 : 12. The total nitrogen removal efficiency was changed between 65.8 and 94.4% and the lowest effluent nitrate concentration was measured as 1.6 mg/l. Seven kinetic models were applied to experimental data to determine the substrate utilization rate. The Monod and Haldane models were ideal to estimate the reactor performance. Moreover, the cost performance evaluation indicated the A2O bioreactor capability in low energy consumption for MIW treatment. According to the modeling results, integrating anaerobic and aerobic zones within a single bioreactor could be beneficial and cost‐effective due to the high effluent quality and low operational costs.

show abstract

Optimization Methodology for High COD Nutrient-Limited Wastewaters Treatment Using BAS Process

Revilla¹,

Galán

Viguri

2018

Water Air Soil Pollut

View full text Add to dashboard Cite

Optimization of biofilm activated sludge (BAS) process via mathematical modelling is an entangle activity since economic, environmental objective and technical decision must be considered. This paper presents a methodology to optimize the operational conditions of BAS process in four steps by combining dynamic simulation techniques with nonlinear optimization methods and with operative decision making criteria. Two set of variables are separately prioritized in the methodology: essential variables related to physical operation to enforce established process performance, and refinement variables related to biological processes that can generate risks of bulking, pinpoint floc and rising sludge. The proposed optimization strategy is applied for the treatment of high COD wastewater under nutrient limitation using an integrated mathematical model for COD removal that include predation, hydrolysis and a simplified approach to the limiting solids flux theory in the secondary clarifier in order to facilitate the convergence of the optimization solver. The methodology is implemented in a full scale wastewater treatment plant for a cellulose and viscose fibre mill obtaining: i) improvement of the effluent quality index (Kg pollution/m 3) up to 62% and, ii) decrease the operating cost index (€/m 3) of the process up to 30% respect the regular working operational conditions of the plant. The proposed procedure can be also applied to other biological treatments treating high COD nutrient-limited industrial wastewater such as from textile and winery production among others. Modelling of biofilm stages and activated sludge provided a better understanding of the intrinsic connections between soluble and particulate compounds, biomass properties and process performance in terms of COD, BOD and TSS (Fan et al. 2017). Commercial simulation platforms, including GPS-X and BioWin can be used to describe the one dimensional (1-D) multi-species biofilm structure and biological behaviour of the treatment process (Li et al. 2016); however, none of these platforms include the description of the predator microorganism which plays a predominant role in a BAS process under certain conditions such as nutrient limited conditions (Revilla et al. 2016a). The authors published recently the mathematical model of BAS process including hydrolysis and predation and uses wastewaters coming from viscose and cellulose production industrial process to validate the model. In Revilla et al. 2016a the whole BAS process was simulated and the evaluation of the role and contribution of predator microorganisms towards COD removal, nutrient requirements and sludge production is displayed. More strict regulations are being imposed regularly in terms of COD, BOD and TSS removal that enforce wastewater treatment technologies to progress (Guerrero et al. 2011; Kamali and Khodaparast 2015). Optimization of an existing facility in terms of cost, operational improvements and removal efficiency is the most effective method of achieving the stricter compliance and the mo...

show abstract

Modeling of multimode anaerobic/anoxic/aerobic wastewater treatment process at low temperature for process optimization

Cited by 34 publications

References 25 publications

Molasses wastewater treatment and lipid production at low temperature conditions by a microalgal mutant Scenedesmus sp. Z-4

Molasses wastewater treatment and lipid production at low temperature conditions by a microalgal mutant Scenedesmus sp. Z-4

Modeling the kinetics and cost performance index of high rate up‐flow anaerobic, anoxic, oxic bioreactor for meat wastewater treatment

Optimization Methodology for High COD Nutrient-Limited Wastewaters Treatment Using BAS Process

Contact Info

Product

Resources

About