Time filter

Source Type

Huang T.-L.,Xi'an University of Architecture and Technology | Zhang G.,Xi'an University of Architecture and Technology | Zhang G.,University of Jinan | Guo N.,Water Authorities of Changping District | And 3 more authors.
Water Science and Technology | Year: 2010

Pelleting flocculation blanket (PFB) process has been successfully applied to high turbidity suspensions for high efficient solid/liquid separation. In this paper, by using the PFB process, a dynamic experimental study was carried out on concentrating ferric flocs sludge with a scale of 1.3-5.4m3/h. The pilot experiment aimed to optimize the conditioning system and determine the operational parameters. Under the raw sludge concentrations of 103-1,154 mg/L, the system could achieve ideal conditioning effect with polyacrylamide (PAM) dosages of 0.3-2.7 mg/L, agitation speed of 10 rpm, and water up-flow rates of 18-48 m/h. Under the experimental conditions, the increase of polymer dosage would improve effluent turbidity and pellets settling behaviour, the moderate up-flow rate had no marked effect on treatment results, while too large surface loading could worsen effluent turbidity. The experimental results also revealed that there existed an approximately linear relationship between the raw sludge concentration and optimum PAM dosage, that is, the optimum dosage of PAM increased synchronously as the raw sludge concentration increased. While the relationship between the raw sludge concentration and maximum up-flow rate reflected another linear dependence, namely, the maximum up-flow rate would decreased linearly as the raw sludge concentration increased. © IWA Publishing 2010.


Zhang G.,Xi'an University of Architecture and Technology | Zhang G.,University of Jinan | Huang T.-L.,Xi'an University of Architecture and Technology | Tan C.,Xi'an University of Architecture and Technology | And 4 more authors.
Water Science and Technology | Year: 2010

Pellet flocs' settling velocity is an important parameter in the pelleting flocculation blanket (PFB) process, hence, it is necessary to investigate flocs' settling behaviour to achieve the optimum operation parameters of the process. To investigate the settling behaviour of pellets under different operational conditions, a dynamic experiment was carried out to concentrate ferric flocs sludge by pelleting flocculation blanket (PFB) process with the scale of 0.5-1.2 m3/h. Under different operating conditions such as raw water concentration, polyacrylamide (PAM) dosage, up-flow rate, and agitation speed, pellet particles were sampled from different locations of the blanket in various operating stages to analyze pellet size, setting velocity, and porosity. Experimental results indicated that, when the PAM dosage increased from 0.59 mg/L to 1.18 mg/L, pellets size would flocculated from 2.25mm to 3.52 mm with the settling velocity accelerated from 3.28 mm/s to 7.37 mm/s, while under the same up-flow rate, agitation intensity and PAM dosage, accompany with the raw water concentration increased from 216 mg/L to 840 mg/L, pellets settling velocity would improved from 6.03mm/s to 13.6 mm/s. Under the experimental condition, along with the up-flow rate increased from 13.3 m/h to 40 m/h, pellets settling velocity would decreased from 4.39 mm/s to 3.42 mm/s due to its lower density. © IWA Publishing 2010.


Gao G.W.,Harbin Institute of Technology | He W.J.,Harbin Institute of Technology | He W.J.,Tianjin Waterworks Group Co. | Li C.,Tianjin Huabo Waterworks Co. | Hu J.K.,Tianjin Waterworks Group Co.
Advanced Materials Research | Year: 2011

Production wastewater (PWW) produced at water treatment plants is an inescapable byproduct and most of it has long been treated as a waste. UF offers a suitable treatment for PWW in order to guarantee a water quality necessary for reuse. The aim of this study was to evaluate the performance of submerged membrane filtration for reducing NOM and the effects of backwash. Turbidity was almost removed to less than 0.11NTU and the removal rate of each series of particle size could be 99.99%. In a membrane-blocking formation comparable filtration system, the filtration resistance due to cake formation fouling was far more three-fold higher than that due to concentration polarization. The minimum TMP due to membrane fouling progressively increased from 0.052 MPa to 0.055 MPa during the operation. Backwash operation can effectively restrain particle fouling and therefore reduce filtration resistances, especially for the cake resistance. The TMP decreases from 0.065 MPa to 0.053MPa after backwash operation. © (2011) Trans Tech Publications.


Wei C.,Harbin Institute of Technology | He W.,Harbin Institute of Technology | He W.,Tianjin Waterworks Group Co. | Wei L.,Harbin Institute of Technology | And 2 more authors.
PLoS ONE | Year: 2015

In this study, high-throughput pyrosequencing was applied on the analysis of the microbial community of activated sludge and biofilm in a lab-scale UV/O3- anaerobic/aerobic (A/O) integrated process for the treatment of petrochemical nanofiltration concentrate (NFC) wastewater. NFC is a type of saline wastewater with low biodegradability. From the anaerobic activated sludge (Sample A) and aerobic biofilm (Sample O), 59,748 and 51,231 valid sequence reads were obtained, respectively. The dominant phylotypes related to the metabolism of organic compounds, polycyclic aromatic hydrocarbon (PAH) biodegradation, assimilation of carbon from benzene, and the biodegradation of nitrogenous organic compounds were detected as genus Clostridium, genera Pseudomonas and Stenotrophomonas, class Betaproteobacteria, and genus Hyphomicrobium. Furthermore, the nitrite-oxidising bacteria Nitrospira, nitrite-reducing and sulphate-oxidising bacteria (NR-SRB) Thioalkalivibrio were also detected. In the last twenty operational days, the total Chemical Oxygen Demand (COD) and Total Organic Carbon (TOC) removal efficiencies on average were 64.93% and 62.06%, respectively. The removal efficiencies of ammonia nitrogen and Total Nitrogen (TN) on average were 90.51%and 75.11% during the entire treatment process. © 2015 Wei et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


Wei C.,Harbin Institute of Technology | He W.,Tianjin Waterworks Group Co. | Wei L.,Harbin Institute of Technology | Li C.,Harbin University of Commerce | And 2 more authors.
Desalination and Water Treatment | Year: 2016

In this study, a laboratory-scale biodegradation, electron transfer based on sulfur metabolism integrated (BESI®) process was used on the treatment of petrochemical reverse osmosis concentrate (ROC). ROC is a type of saline wastewater with low biodegradability. In the operational days, the chemical oxygen demand (COD) and total organic carbon removal efficiencies on average were 79.18 and 79.39%, respectively. The removal efficiencies of ammonia nitrogen and total nitrogen on average were 79.84 and 83.60%, respectively. High-throughput pyrosequencing was applied on the analysis of the microbial community in activated sludge and biofilm samples. The functional phylotypes sulfate-reducing bacteria (SRB) were detected in anaerobic reactor, and they participated in the COD removal and sulfate reduction. The genera Hyphomicrobium, Azoarcus, Thauera, Paracoccus, and Nitrospira were detected in the BESI® process. These genera contributed to the nitrogen transformation, and they played different roles in each reactor of the integrated process. © 2016 Balaban Desalination Publications. All rights reserved.


Huang T.,Xi'an University of Architecture and Technology | Wei W.,Tianjin Waterworks Group Co. | Su J.,Xi'an University of Architecture and Technology | Zhang H.,Xi'an University of Architecture and Technology | Li N.,Xi'an University of Architecture and Technology
PLoS ONE | Year: 2012

The contamination of surface water by nitrogen due to fertilizer application and discharge of wastewater is an increasingly serious problem. A multifunctional device, which combines water-lifting and aeration (WLA) with oligotrophic biological contact oxidation (OBCO), was developed for pretreatment of raw water to reduce nitrogen. The performance of nitrogen removal and changes in microbial community structure were investigated. The results showed that the combined technique of WLA-OBCO was feasible, and that ammonium, nitrate, total nitrogen and total organic carbon were effectively removed. Meanwhile, nitrite was mostly undetectable. The PCR-DGGE and clone sequencing results revealed that α-proteobacterium was the largest bacterial group, and Pseudomonas strains Y3 and J8 were the dominant bacteria. © 2012 Huang et al.


Tan H.,Harbin Institute of Technology | He W.,Harbin Institute of Technology | He W.,Tianjin Waterworks Group Co. | Han H.,Tianjin Waterworks Group Co. | And 4 more authors.
Chinese Journal of Environmental Engineering | Year: 2013

With sodium hydroxide being added into conventional water treatment process, the study on cadmium removal in polluted water was carried out. The results showed that the method removed cadmium effectively and steadily, which can be used in emergency treatment. Affecting factors of pH, cadmium concentration and coagulant dosage were analyzed by gray correlation analysis. The analysis indicated that gray correlation grade of affecting factors was pH in effluent of filtration>coagulant dosage>cadmium concentration. When cadmium pollution happens in source water, cadmium is removed by adjusting the pH in effluent of filtration in conventional water treatment. The control value of pH is relevant to source water quality.


Tan H.Q.,Harbin Institute of Technology | He W.J.,Harbin Institute of Technology | He W.J.,Tianjin Waterworks Group Co. | Han H.D.,Harbin Institute of Technology
Advanced Materials Research | Year: 2014

Analyzing the seasonal variation of water quality, the indices which include total iron, pH, temperature, DO, alkalinity and hardness were of high statistical significance, and total iron had a high correlation with temperature, which influences many parameters influencing iron release, such as DO, solution viscosity, thermodynamic properties and microbial activity. Therefore, it can be concluded that temperature is a main factor that affects iron release in seasonal change for drinking water distribution systems. Variation in season and temperature should be paid attention to in practice of water supply. © (2014) Trans Tech Publications, Switzerland.


Ma H.,Harbin Institute of Technology | Cui F.,Harbin Institute of Technology | Liu Z.,Harbin Institute of Technology | Fan Z.,Harbin Institute of Technology | And 2 more authors.
Journal of Environmental Sciences | Year: 2010

Silver carp were introduced into the pre-sedimentation pond to control excessive phytoplankton in raw water. The effectiveness of the filter-feeding silver carp on phytoplankton control and the effect of silver carp on phytoplankton community were investigated. The results showed that Microcystis could be effectively removed by silver carp stocked in the pre-sedimentation pond, and simultaneously, the concentration of single-cell phytoplankton increased obviously. The difference in phytoplankton species and single-cell phytoplankton size between in the water and in the gut of silver carp indicated that phytoplankton smaller than 5 μm, such as Chamydomonas and Platymonas, were almost not be filtered by silver carp, phytoplankton with the size between 5 and 20 μm could be partly filtered, and large size phytoplankton, mainly colony-forming Microcystis could be filtered almost completely. These filter-feeding characteristics directly caused the phytoplankton size distribution biased toward miniaturization. Therefore, this biological treatment using silver carp could be applied only to deal with groups of Microcystis-dominated eutrophic water, and was not appropriate in water bodies where single-cell micro phytoplankton were dominant. Especially when silver carp are used in water treatment, a cautious attitude should be taken based on the evaluation of phytoplankton biomass and species structure features in raw water. © 2010 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences.


Zheng C.-Z.,Harbin Institute of Technology | Gao J.-L.,Harbin Institute of Technology | He W.-J.,Harbin Institute of Technology | He W.-J.,Tianjin Water Works Group Co.
Zhejiang Daxue Xuebao (Gongxue Ban)/Journal of Zhejiang University (Engineering Science) | Year: 2016

A new leakage discharge analysis model based on fast independent component analysis (FastICA) algorithm was established in order to solve the problems of the traditional leakage discharge analysis models, such as low simulation accuracy, incapability of reflecting the uncertain relationship between leakage discharge and presssure head and so on. The model divided total water supply flow into actual consumed water flow and leakage discharge and considered them as two source signals. In the model, the total water supply flow and pressure head at the entrance were considered as two input parameters. The waveform information of two flows were obtained by separating source signals. The order of the source signals was determined by comparing the correlation coefficients. The real amplitude of leakage discharge was solved out according to the flow balance equation. Therefore, the leakage discharge was simulated in time series. For this model, the input parameters are easily getparms. It can effectively avoid the complexity of the relationship between leakage discharge and head pressure. Thus the simulation accuracy is high in the water distribution system with one entrance only. The model has been preferably applied in the node demand distribution of one water distribution network's hydraulic model. © 2016, Zhejiang University Press. All right reserved.

Loading Tianjin Waterworks Group Co. collaborators
Loading Tianjin Waterworks Group Co. collaborators