Study on Low Temperature on SBR Process Performance

2010 ◽  
Vol 113-116 ◽  
pp. 770-774
Author(s):  
Xing Bin Sun ◽  
Zhao Chao Hou ◽  
Jin Long Zuo

In order to investigate low-temperature influence on the SBR process and sludge bulking, the SBR process pollutants removal effect was studied with normal and low temperature. The experimental results showed that the effluent water quality was better with temperature 22~24°C and DO 2mg/L. During this period, sludge bulking did not happen and the SVI was stable for 30d at the range of 60~80mL/g. The sludge settlement became worse when the temperature sharply dropped to 13~15°C and DO concentration was unchanged, the SVI was sharply increased to 240~270mL/g from 60~80mL/g in several cycles, and it was in the state of sludge bulking for 60d. The system denitrification effect was almost lost and the nitrification effect had been seriously affected. When the temperature returned to normal, the nitrification effect was gradually improved. The effluent water was clear and the SVI returned gradually, but the SVI eventually maintained at 150mL/g without retune to previous range.

2014 ◽  
Vol 9 (4) ◽  
pp. 475-482 ◽  
Author(s):  
J. Väänänen ◽  
F. Nilsson ◽  
J. la Cour Jansen ◽  
M. Hörsing ◽  
M. Hagman ◽  
...  

The combination of coagulation/flocculation and discfiltration with ozonation to reduce nutrients and organic micro-pollutants in secondary effluent was studied in pilot scale at Lundåkraverket wastewater treatment plant in Landskrona, Sweden. With a chemical dose of 4 gAl3+/m3 and 1.5 g/m3 cationic polymer as active material effluent water quality with regards to total phosphorous (Tot-P), suspended solids and turbidity were 0.03, 2 mg/l and 0.5 Nephelometric Turbidity Units (NTU) in average. The effluent water quality was similar whether ozonation with an applied ozone dose of 2–9 gO3/m3 was performed prior to or after coagulation/flocculation/discfiltration. The results were corresponding to removal efficiencies for the coagulation/flocculation/discfiltration process of 94, 74 and 85% for Tot-P, suspended solids and turbidity, respectively. For organic micro-pollutants removal, it was found to be beneficial to perform coagulation/flocculation/discfiltration prior to ozonation as the ozone requirements were lowered for the dosing intervals applied. The removal was in the range of 38–98% depending on process configuration and ozone dose.


2014 ◽  
Vol 16 (12) ◽  
pp. 2721-2728 ◽  
Author(s):  
Shengnan Xu ◽  
Minghao Sun ◽  
Chiqian Zhang ◽  
Rao Surampalli ◽  
Zhiqiang Hu

Sludge bulking causes loss of biomass in the effluent and deterioration of effluent water quality.


2019 ◽  
Author(s):  
Chem Int

Recently, process control in wastewater treatment plants (WWTPs) is, mostly accomplished through examining the quality of the water effluent and adjusting the processes through the operator’s experience. This practice is inefficient, costly and slow in control response. A better control of WTPs can be achieved by developing a robust mathematical tool for performance prediction. Due to their high accuracy and quite promising application in the field of engineering, Artificial Neural Networks (ANNs) are attracting attention in the domain of WWTP predictive performance modeling. This work focuses on applying ANN with a feed-forward, back propagation learning paradigm to predict the effluent water quality of the Habesha brewery WTP. Data of influent and effluent water quality covering approximately an 11-month period (May 2016 to March 2017) were used to develop, calibrate and validate the models. The study proves that ANN can predict the effluent water quality parameters with a correlation coefficient (R) between the observed and predicted output values reaching up to 0.969. Model architecture of 3-21-3 for pH and TN, and 1-76-1 for COD were selected as optimum topologies for predicting the Habesha Brewery WTP performance. The linear correlation between predicted and target outputs for the optimal model architectures described above were 0.9201 and 0.9692, respectively.


1974 ◽  
Vol 9 (1) ◽  
pp. 25-29
Author(s):  
M. B. Bayer

Abstract This paper describes a method of applying probabilistic DO (dissolved oxygen) and BOD (biochemical oxygen demand) standards in river basin water quality models. Maximum likelihood estimators for the DO and BOD concentrations variances for each reach are used to obtain a lower bound for BOD so that the probability of violating specified DO and BOD standards is less than Θ per cent in any reach. These boundary values for DO and BOD concentrations are incorporated into a nonlinear water quality optimization model for finding the minimum cost set of wastewater treatment plant efficiencies required to meet DO and BOD standards. The method also provides the minimum DO concentration and the maximum BOD concentration which may be expected to occur 1-Θ of the time for any reach.


2019 ◽  
Author(s):  
Trista M. Brophy ◽  
◽  
Steven P. Hohman ◽  
A.J. Reisinger ◽  
Eban Z. Bean ◽  
...  

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Augustine Chung Wei Yap ◽  
Hwang Sheng Lee ◽  
Joo Ling Loo ◽  
Nuruol Syuhadaa Mohd

AbstractpH, oxidation-reduction potential (ORP) and dissolved oxygen (DO) concentration are important parameters in water quality surveillance and treatment. The changes of these parameters are associated with electron density in water. Several techniques including electrolysis and catalysis which require redox reactions and electron exchange are employed to improve these parameters. In recent years, studies reported that magnetic effects can impart considerable changes on the pH, ORP and DO concentration of water. However, the correlation between electron density and magnetic effects on these parameters has yet to be disclosed despite the fact that increased electron density in water could improve water’s reductive properties, heat capacity and hydrogen bonding characteristics. In this study, the magnetic effects on pH, ORP and DO concentration were investigated using different magnets arrangements and water flow rates based on reversed electric motor principle. Results showed that the improvement of pH, ORP and DO concentration from 5.40–5.42 to 5.58–5.62 (+ 3.5%), 392 to 365 mV (− 6.9%), and 7.30 to 7.71 mg L− 1 (+ 5.6%), respectively were achieved using combined variables of non-reversed polarity magnet arrangement (1000–1500 G magnetic strength) and water flow rate of 0.1–0.5 mL s− 1. Such decrement in ORP value also corresponded to 8.0 × 1013 number of electron generation in water. Furthermore, Raman analysis revealed that magnetic effect could strengthen the intermolecular hydrogen bonding of water molecules and favor formation of smaller water clusters. The findings of this study could contribute to potential applications in aquaculture, water quality control and treatment of cancer attributed to free radical induced-oxidative stress.


2021 ◽  
Vol 11 (5) ◽  
Author(s):  
Durai Ganesh ◽  
G. Senthilkumar ◽  
P. Eswaran ◽  
M. Balakrishnan ◽  
S. N. Bramha ◽  
...  

AbstractUranium concentration in the ground water samples from the district of Tiruvannamalai, Tamil Nadu, was measured using an LED fluorimeter. All the samples were qualified as potable water from the radiological perspective. Though some samples showed mild chemical toxicity, they are still safe for ingestion. Different risk coefficients were calculated, and they were compared with recommended safety limits specified by various agencies. Software tools such as QGIS 15, GraphPad Prism 8 and Surfer 15 were employed for developing maps and plots.


2015 ◽  
Vol 41 (1) ◽  
pp. 13-19
Author(s):  
Kaniz Fatema ◽  
Wan Maznah Wan Omar ◽  
Mansor Mat Isa

Water quality in three different stations of Merbok estuary was investigated limnologically from October, 2010 to September, 2011. Water temperature, transparency and total suspended solids (TSS) varied from 27.45 - 30.450C, 7.5 - 120 cm and 10 -140 mg/l, respectively. Dissolved Oxygen (DO) concentration ranged from 1.22-10.8 mg/l, while salinity ranged from 3.5-35.00 ppt. pH and conductivity ranged from 6.35 - 8.25 and 40 - 380 ?S/cm, respectively. Kruskal Wallis H test shows that water quality parameters were significantly different among the sampling months and stations (p<0.05). This study revealed that DO, salinity, conductivity and transparency were higher in wet season and TSS was higher in dry season. On the other hand, temperature and pH did not follow any seasonal trends.Bangladesh J. Zool. 41(1): 13-19, 2013


2012 ◽  
Vol 518-523 ◽  
pp. 2130-2137
Author(s):  
Si Hao Lv ◽  
Hui Chang ◽  
Zhi Hui Liang ◽  
Yan Yan Zeng ◽  
Hong Bo Fan

A pilot study was carried out to evaluate the application of aerobic submerged MBR in treating polyester wastewater and a full scale system in which MBR was adopted as the key aspect was put forward to treat the polyester wastewater of Zhuhai Yuhua Polyester co., Ltd., China. The pilot study revealed that HRT could be affected by the influent COD, and a HRT larger than 36h was proposed for treating polyester wastewater by MBR. Volumetric loading rate and sludge loading rate ranged in 0.7-2.0 kgCOD/m3•d and 0.09~0.24 kgCOD/ kgMLSS•d respectively were of small influence on the COD removal. DO in the range of 2.5-4.0 mg/L seemed to be optimal for avoiding limitations due to oxygen concentration and creating an effective turbulence. The modified full scale system which includes anaerobic digesting tank and MBR followed by a stabilization pond was verified to be effective to treat the polyester wastewater in the latest two years. The results illustrated that the effluent water quality could meet the discharge limits of water pollutants (DB 44/26-2001) which was established in Guangdong, China. Observed sludge yield of the system fluctuated between 0.10-0.18 gMLSS/gCOD and averaged at 0.137 gMLSS/gCOD. The membrane permeate at around 10 L/m2h, TMP of less than 0.7bar, and total mixed liquor suspended solids (MLSS) between 6-7g/L were suitable to operate the MBR.


2011 ◽  
Vol 332-334 ◽  
pp. 27-30 ◽  
Author(s):  
Mei Niu ◽  
Zi Lu Wu ◽  
Jin Ming Dai ◽  
Wen Sheng Hou ◽  
Sheng Shi ◽  
...  

Wool fiber was firstly pretreated by nano-SiO2/Ag antibacterial agent, and then dyed with an acid dyes at low temperature by ultrasonic dyeing. Many factors had an important influence on the dye ability and the antibacterial behavior during the dyeing process of antibacterial wool fiber. The experimental results indicate that the dye-takeup rates of antibacterial wool fiber were enhanced with the increase of the concentration of nano-SiO2/Ag, the dyeing temperature, the dyeing time and the ultrasonic frequency (less than 60Hz). However, the antibacterial ratios of wool fiber were declined in the impact of these factors other than the concentration of antibacterial agent.


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