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Fouling behavior of poly(vinylidene fluoride)(PVDF)ultrafiltration membrane by polyvinyl alcohol(PVA)and chemical cleaning method

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Chinese Journal of chemical Engineering 2020年第12期28卷 3018-3026页

作者： Weijie Ding Min Chen Ming Zhou Zhaoxiang Zhong Zhaoliang Cui Weihong Xing State Key Laboratory of Materials-Oriented chemical Engineering National Engineering Research Center for Special Separation MembraneNanjing Tech UniversityNanjing 211816China

Severe fouling to poly(vinylidene fluoride)(PVDF)membrane is usually caused as filtrating the papermaking wastewater in the ultrafiltration(UF)*** the paper,fouling behavior and mechanism were investigated,and the low-concentration polyvinyl alcohol(PVA)contained in the sedimentation tank wastewater was found as the main ***,the corresponding cleaning approach was *** experiment and modeling results elaborated that the fouling mode developed from pore blockage to cake layer along with filtration *** cleaning conditions including the composition and concentration of reagents,cleaning duration and trans-membrane pressure were investigated for their effect on cleaning *** water flux was recovered by over 95% after cleaning the PVDF membrane using the optimal conditions 0.5 wt% NaClO(as oxidant)and 0.1 wt% sodiumdodecyl benzene sulfonate(SDBS,as surfactant)at 0.04MPa for 100 *** the chemical cleaning method,hypochlorite(ClO−)could first chain-scissor PVA macromolecules to small molecules and SDBS could wrap the fragments in micelles,so that the foulants were removed from the pores and surface of *** eight cycling tests,pure water flux recovery maintained above 95% and the reused membrane was found intact without defects.

关键词： PVDF membrane Fouling PVA chemical cleaning

Application of response surface methodology to the chemical cleaning process of ultrafiltration membrane

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Chinese Journal of chemical Engineering 2016年第5期24卷 651-657页

作者： Caihong Wang Aishu Wei Hao Wu Fangshu Qu Weixiong Chen Heng Liang Guibai Li State Key Laboratory of Urban Water Resource and Environment(SKLUWRE) Harbin Institute of Technology73 Huanghe RoadNangang DistrictHarbin 150090China The Architecture Design and Research Institute of Guangdong Province Guangzhou 510100China China Urban Construction Design&Research Institute Beijing 100120China School of Environment and Energy South China University of TechnologyGuangzhou 510006China

A numerical model was established to predict and optimise the chemical cleaning process of Polyvinylidene Fluo- ride （PVDF） Ultrafiltration （UF） membranes with the results from the experiment that applied the Response Sur- face Method （RSM） and Central Composite Design （CCD）. The factors considered in the experimental design were sodium hydroxide （NaOH） concentration, sodium bypochlorite concentration （NaCIO）, citric acid concentration and cleaning duration, The interactions between the factors were investigated with the numerical model. Humic acid （20 mg· L-1） was used as the model foulant, and chemical enhanced backflush （CEB） was employed to sim- ulate the chemical cleaning process. The concentrations of sodium hydroxide, sodium hypochlorite, citric acid and cleaning duration tested during the experiments were in the range of 0.1%-0.3% 100-300 mg· L-1 1%-3% and 0.5-1.5 h, respectively. Among the variables, the sodium hypochlorite concentration and the cleaning dura- tion showed a positive relationship involving the increased efficiency of the chemical cleaning. The chemical cleaning efficiency was hardly improved with increasing concentrations of sodium hydroxide. However, the data was sharply decreased when at a low level of sodium hydroxide concentration. In total, 54 sets of cleaning schemes with 80% to 100K cleaning efficiency were observed with the R＆M model after calibration.

关键词： Ultrafiltration Response surface methodology chemical cleaning Water treatment

Application of heat-activated peroxydisulfate process for the chemical cleaning of fouled ultrafiltration membranes

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Chinese chemical Letters 2023年第10期34卷 116-120页

作者： Jiaqi Ding Haoliang Xiao Xiaolong Huang Yujia Zou Zhimin Ye Songlin Wang Pengchao Xie Yongsheng Chen Jun Ma Yangtze River Basin Ecological Environment Monitoring and Scientific Research Center Yangtze River Basin Ecological Environment Supervision and Administration BureauMinistry of Ecological EnvironmentWuhan 430010China School of Environmental Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Water&Wastewater Treatment(HUST) MOHURDWuhan 430074China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA 30332United States State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150090China

Na Cl O has been widely used to restore membrane flux in practical membrane cleaning processes,which would induce the formation of toxic halogenated *** this study,we proposed a novel heatactivated peroxydisulfate(heat/PDS)process to clean the membrane fouling derived from humic acid(HA).The results show that the combination of heat and PDS can achieve almost 100%recovery of permeate flux after soaking the HA-fouled membrane in 1 mmol/L PDS solution at 50℃ for 2 h,which is attributed to the changes of HA structure and enhanced detachment of foulants from *** properties of different treated membranes are characterized by scanning electron microscopy(SEM),atomic force microscope(AFM),attenuated total reflection Fourier transform infrared spectroscopy(ATRFTIR),and X-ray photoelectron spectroscopy(XPS),demonstrating that the reversible and irreversible foulants could be effectively removed by heat/PDS *** filtration process and fouling mechanism of the cleaned membrane were close to that of the virgin membrane,illustrating the good reusability of the cleaned ***,heat/PDS which can avoid the generation of halogenated byproducts shows comparable performance to Na Cl O on membrane cleaning and high performance for the removal of fouling caused by sodium alginate(SA),HA-bovine serum albumin(BSA)-SA mixture and algae,further suggesting that heat/PDS would be a potential alternative for membrane cleaning in practical application.

关键词： chemical cleaning Peroxydisulfate Heat Membrane fouling Ultrafiltration

Research and Application of New chemical cleaning Process for Titanium-Made Equipment

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Electricity 2002年第1期13卷 17-22页

作者：许正军莫逆杨福锁刘伯东华北电力科学研究院天津大港发电厂

Based on the research on corrosion-resistance of titanium in various media and a great deal of tests, a newchemical cleaning process for titanium-made equipment was developed and applied to titanium-made heat exchangersof a homemade multi-stage flash distiller for sea-water desalination in Tianjin Dagang Power Plant. Scale in the tubeswas removed completely as inspected by the experts. Testing results of hydrogen content and metallographic structureof titanium tubes showed that the cleaning was successful without any damages to the equipment.[

关键词： titanium flash distillation corrosion chemical cleaning

Formation of disinfection by-products during sodium hypochlorite cleaning of fouled membranes from membrane bioreactors

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Frontiers of Environmental Science & Engineering 2021年第5期15卷 271-281页

作者： Hao Wang Defang Ma Weiye Shi Zhiyu Yang Yun Cai Baoyu Gao Shandong Key Laboratory of Water Pollution Control and Resource Reuse School of Environmental Science and EngineeringShandong UniversityQingdao266237China No.1 Institute of Geology and Mineral Resources of Shandong Province Jinan250014China Shandong Engineering Laboratory for High-Grade Fe Ores Exploration and Exploitation Jinan250014China

Periodic chemical cleaning with sodium hypochlorite(NaClO)is essential to restore the membrane permeability in a membrane bioreactor(MBR).However,the chlorination of membrane foulants results in the formation of disinfection by-products(DBPs),which will cause the deterioration of the MBR effluent and increase the antibiotic resistance in bacteria in the MBR *** this study,the formation of 14 DBPs during chemical cleaning offouled MBR membrane modules was *** with the effects of biofilm extracellular polymeric substances(EPS),influences of reaction time,NaClO dosage,initial pH,and cleaning temperature on the DBP formation were *** acids(HAAs)and trichloromethane(TCM),composed over 90%of the DBPs,were increasingly accumulated as the NaClO cleaning time *** increasing the chlorine dosage,temperature,and pH,the yield of TCM and dichloroacetic acid(DCAA)was increased by up to a factor of 1–14,whereas the yields of haloacetonitriles(HANs)and haloketones(HKs)were *** decreasing in the chlorine dosage and cleaning temperature or adjusting the pH of cleaning reagents toward acidic or alkaline could effectively reduce the toxic risks caused by *** the EPS extraction pretreatment,the formation of DBPs was accelerated in the first 12 h due to the damage of biofilm *** laser scanning microscopy(CLSM)images showed that EPS,particularly polysaccharides,were highly resistant to chlorine and might be able to protect the cells exposed to chlorination.

关键词： MBR Biofouling EPS chemical cleaning DBPs CLSM

Using loose nanofiltration membrane for lake water treatment:A pilot study

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Frontiers of Environmental Science & Engineering 2021年第4期15卷 251-261页

作者： Danyang Liu Johny Cabrera Lijuan Zhong Wenjing Wang Dingyuan Duan Xiaomao Wang Shuming Liu Yuefeng F.Xie State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Chengdu Xingrong Environmental Co. Ltd.Chengdu610041China Civil and Environmental Programs Penn State UniversityMiddletownPA17057USA

Nanofiltration(NF)using loose membranes has a high application potential for advanced treatment of drinking water by selectively removing contaminants from the water,while membrane fouling remains one of the biggest problems of the *** paper reported a seven-month pilot study of using a loose NF membrane to treat a sand filtration effluent which had a relatively high turbidity(∼0.4 NTU)and high concentrations of organic matter(up to 5 mg/L as TOC),hardness and *** showed that the membrane demonstrated a high rejection of TOC(bycleaning was not effective in removing the membrane foulants,the use of ethylenediamine tetraacetate(EDTA)at alkaline conditions could effectively restore the membrane permeance.

关键词： Nanofiltration Drinking water Membrane fouling Aluminum carryover chemical cleaning

Green production of sugar by membrane technology:How far is it from industrialization?

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Green chemical Engineering 2021年第1期2卷 27-43页

作者： Hao Zhang Jianquan Luo Lulu Liu Xiangrong Chen Yinhua Wan State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing100190China School of chemical Engineering University of Chinese Academy of SciencesBeijing100049China

Application of membrane filtration in sugar production is attractive because it can reduce the usage of chemicals,produce high-quality clarified juice,and obtain various high value-added ***,some technical problems,such as insufficient membrane performance,high sucrose loss in membrane retentate,severe membrane fouling,and incomplete cleaning protocols,limit its industrial *** order to facilitate the development of membrane technology for sugar production,this review summarizes recent progress on the applications of membrane filtration in different stages of sugar production as well as the integrated membrane processes for various ***,some important issues including membrane fouling,membrane cleaning,economic feasibility and engineering problems of the membrane-based sugar production process are ***,the existing challenges and future research prospects for the industrialization of this green technique are pointed out.

关键词： Sugar production Molasses Membrane fouling chemical cleaning Industrialization

Study of Oil-Bearing Drill Cuttings cleaning and De-Oiling Treatment Method for Shale Gas Reservoirs

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Energy Engineering 2023年第8期120卷 1899-1917页

作者： Jialuo Rong Shuixiang Xie Huijing Geng Hao Hu Shanfa Tang Yuanpeng Cheng School of Petroleum Engineering Yangtze UniversityWuhan430100China Key Laboratory of Drilling and Production Engineering for Oil and Gas Wuhan430100China State Key Laboratory of Petroleum and Petrochemical Pollutant Control and Treatment Beijing102206China China National Petroleum Group Safety and Environmental Protection Technology Research Institute Co. Ltd.Beijing102206China Underground Gas Storage Branch CNPCBeijing100101China

Due to its extensive use in shale gas exploration and development,oil-based drilling fluids generate large amounts of oil-bearing drill cuttings during the drilling *** large amount of oil-bearing drill cuttings generated during the drilling process can lead to serious secondary *** this study,a wetting agent FSC-6 with good hydrophobic and oleophobic properties was synthesized to construct an efficient oil removal *** the first time,the mechanism of this system was analyzed by using the theory of adhesion function,interfacial tension and *** the same time,a combined acoustic-chemical treatment process was applied to the wastewater and slag generated after the cleaning of the oil-bearing drill *** experimental results show that the application of this pollution-free technology can effectively solve the environmental pollution and resource recovery problems of oil-bearing drill *** meets the standard of drilling chips with oil content less than 2%in SY/T7422-2018“Oil-based drilling fluid drilling chips treatment system for oil and gas drilling equipment”.

关键词： Oil-bearing drill cuttings fluorocarbon surfactants chemical cleaning ultrasonic cleaning oil content rate

Pilot study on treatment of low turbidity and low temperature water by coagulation-immersed membrane process

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Journal of Harbin Institute of Technology(New Series) 2011年第2期18卷 37-42页

作者：康华何文杰韩宏大李辰 School of Municipal and Environmental Engineering Harbin Institute of Technology Tianjin Water Group Corp. School of Environmental and Municipal Engineering Xi'an University of Architecture and Technology

The objective of this paper was to investigate the practicability of coagulation-immersed membrane process during low-temperature period through the study of steady operation,chemical cleaning methods,water quality and agent *** results showed that:membrane performance decreases with the reduction of temperature,but low temperature has little effect on stable operation of immersed membrane when coagulation as *** with 1200 mg/L sodium hypochlorite after every 48 filtration cycles was made for reducing membrane fouling efficiently,and the method,with 1.5% sodium hydroxide and 3500 mg/L sodium hypochlorite for 10 h and then 2% hydrochloric acid for 4 h,is an appropriate cleaning method under low *** with convention treatment process,immersed membrane process not only has same agent consumption,but also permeated water quality is more superior such as fine removal effect on turbidity with average 0.10 ***,coagulation-immersed membrane process is more appropriate for increasing water quality demand and the treatment of low turbidity and low temperature water.

关键词： low temperature coagulation-immersed membrane process filter performance chemical cleaning water quality