Effects of High Salinity on Alginate Fouling during Ultrafiltration of High-Salinity Organic Synthetic Wastewater

Ultrafiltration is widely employed in treating high-salinity organic wastewater for the purpose of retaining particulates, microbes and macromolecules etc. In general, high-salinity wastewater contains diverse types of saline ions at fairly high concentration, which may significantly change foulant properties and subsequent fouling propensity during ultrafiltration. This study filled a knowledge gap by investigating polysaccharide fouling formation affected by various high saline environments, where 2 mol/L Na+ and 0.5-1.0 mol/L Ca2+/Al3+ were employed and the synergistic influences of Na+-Ca2+ and Na+-Al3+ were further unveiled. The results demonstrated that the synergistic influence of Na+-Ca2+ strikingly enlarged the alginate size due to the bridging effects of Ca2+ via binding with carboxyl groups in alginate chains. As compared with pure alginate, the involvement of Na+ aggravated alginate fouling formation, while the subsequent addition of Ca2+ or Al3+ on the basis of Na+ mitigated fouling development. The coexistence of Na+-Ca2+ led to alginate fouling formed mostly in a loose and reversible pattern, accompanied by significant cracks appearing on the cake layer. In contrast, the fouling layer formed by alginate-Na+-Al3+ seemed to be much denser, leading to severer irreversible fouling formation. Notably, the membrane rejection under various high salinity conditions was seriously weakened. Consequently, the current study offered in-depth insights into the development of polysaccharide-associated fouling during ultrafiltration of high-salinity organic wastewater.

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Analysis of Key Technologies for Industrialized Treatment of Fatty Acid High-Salinity Organic Wastewater

Journal of Korean Society of Environmental Engineers ◽

10.4491/ksee.2020.42.11.570 ◽

2020 ◽

Vol 42 (11) ◽

pp. 570-579

Author(s):

Qinfang Lu ◽

Byung-gon Jeong ◽

Ping Yan ◽

Sohee Kim ◽

Shirong Lai ◽

...

Keyword(s):

Fatty Acid ◽

Process Optimization ◽

Biological Treatment ◽

High Efficiency ◽

High Salinity ◽

Pollution Prevention ◽

Treatment Method ◽

High Concentration ◽

Treatment Technology ◽

Organic Wastewater

Objectives : Wastewater produced by fatty acid production contains high concentration of organic substances and high concentration of salts (mainly sodium sulfate), causing great pollution to water resources and environment. The pollution prevention and control of this type of wastewater are very necessary. The key to treating this type of wastewater is to remove salts and COD to achieve harmless treatment. This is a problem in wastewater management that has plagued the industry for a long time. This paper proposed a technique suitable for fatty acid high salinity organic wastewater.Methods : First, the industrial treatment technology of organic wastewater with high salinity was introduced and analyzed. Combined with the principle of industrial wastewater treatment, the process route for the treatment of fatty acid high salinity organic wastewater was analyzed and selected. In addition, the key technology and process for anaerobic desalination and COD removal were analyzed and selected.Results and Discussion : According to the unique nature of this type of wastewater mainly containing sulphate salts and the feasibility of industrial production, a special technology combination was proposed to treat this wastewater at this stage. Since this wastewater has a B/C ratio of 0.4 to 0.45, it is easier to use biological treatment method. Thus, the conventional treatment method is pretreatment + biological treatment. Biological enhancement and reactor process optimization can be studied for better efficiency.Conclusions : Considering the high COD and sulphate concentration characteristics of fatty acid high-salinity organic wastewater, high-efficiency anaerobic biochemical treatment is mainly considered. Combined with modern high-efficiency anaerobic suspended sludge granule technology, it was concluded that pretreatment + high efficiency IC anaerobic + secondary biological treatment can achieve industrialized treatment of such wastewater in a targeted, low-cost and reliable way. In the later stage, bio-enhancement of the anaerobic process as well as structural and process optimization of the reactor can be carried out to obtain better technical and economic results in production practice.

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Nitrogen Removal in a Real-Time Controlled Sequencing Batch Membrane Bioreactor

Water Practice & Technology ◽

10.2166/wpt.2010.065 ◽

2010 ◽

Vol 5 (3) ◽

Author(s):

Cheng-Nan Chang ◽

Li-Ling Lee ◽

Han-Hsien Huang ◽

Ying-Chih Chiu

Keyword(s):

Real Time ◽

Nitrogen Removal ◽

Membrane Bioreactor ◽

Synthetic Wastewater ◽

Real Time Control ◽

Time Control ◽

Cake Layer ◽

On Line ◽

Solid Liquid ◽

Solid Liquid Separation

The performance of a real-time controlled Sequencing Batch Membrane Bioreactor (SBMBR) for removing organic matter and nitrogen from synthetic wastewater has been investigated in this study under two specific ammonia loadings of 0.0086 and 0.0045g NH4+-N gVSS−1 day−1. Laboratory results indicate that both COD and DOC removal are greater than 97.5% (w/w) but the major benefit of using membrane for solid-liquid separation is that the effluent can be decanted through the membrane while aeration is continued during the draw stage. With a continued aeration, the sludge cake layer is prevented from forming thus alleviating the membrane clogging problem in addition to significant nitrification activities observed in the draw stage. With adequate aeration in the oxic stage, the nitrogen removal efficiency exceeding 99% can be achieved with the SBMBR system. Furthermore, the SBMBR system has also been used to study the occurrence of ammonia valley and nitrate knee that can be used for real-time control of the biological process. Under appropriate ammonia loading rates, applicable ammonia valley and nitrate knee are detected. The real-time control of the SBMBR can be performed based on on-line ORP and pH measurements.

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Integration of electrodialysis and Donnan dialysis for the selective separation of ammonium from high-salinity wastewater

Chemical Engineering Journal ◽

10.1016/j.cej.2020.127001 ◽

2021 ◽

Vol 405 ◽

pp. 127001

Author(s):

Rui Ding ◽

Ziyi Ding ◽

Xiongjian Chen ◽

Jianling Fu ◽

Zijing Zhou ◽

...

Keyword(s):

High Salinity ◽

Selective Separation ◽

Donnan Dialysis ◽

Salinity Wastewater

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Fluid bed biological nitrification and denitrification in high salinity wastewater

Water Science & Technology ◽

10.1016/s0273-1223(97)00341-7 ◽

1997 ◽

Vol 36 (1) ◽

Cited By ~ 20

Keyword(s):

High Salinity ◽

Fluid Bed ◽

Nitrification And Denitrification ◽

Biological Nitrification ◽

Salinity Wastewater

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Efficient degradation of phenol with high salinity wastewater by catalytic persulfate activation using chitosan biochar

Reaction Kinetics Mechanisms and Catalysis ◽

10.1007/s11144-021-02150-1 ◽

2022 ◽

Author(s):

Maojuan Bai ◽

Deli Niu ◽

Liquan Xia ◽

Yajie Yin ◽

Jun Wan

Keyword(s):

High Salinity ◽

Persulfate Activation ◽

Salinity Wastewater

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Assessment of High Salinity Wastewater Treatment with Dewatered Alum Sludge-Aerobic Membrane Reactor

Ecological Chemistry and Engineering S ◽

10.2478/eces-2021-0030 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Wei Kang ◽

Xiyu Cui ◽

Yanrui Cui ◽

Linlin Bao ◽

Kaili Ma

Keyword(s):

Membrane Reactor ◽

High Salinity ◽

Oxygen Demand ◽

Ammonia Nitrogen ◽

Organic Content ◽

Organic Loading Rate ◽

Soluble Phosphate ◽

Aquatic Life ◽

Alum Sludge ◽

Salinity Wastewater

Abstract The discharge of wastewater containing both high salinity and high organic content without prior treatment is detrimental to aquatic life and water hygiene. In order to integrate the advantages of membrane treatment and biological treatment, and exert the phosphorus removal efficiency of dewatered alum sludge, in this study, an aerobic membrane reactor based on dehydrated alum sludge was used to treat mustard tuber wastewater with salinity of 6.8-7.3 % under the conditions of 30 °C, 20 kPa trans-membrane pressure (TMP) and chemical oxygen demand (COD) of 3300-3900 mg/L. Three replicate reactors were applied to assess the operational performance under different organic loading rate (OLR). The results showed that all reactors were effective in removing COD, ammonia nitrogen (NH4 +-N) and soluble phosphate (SP) under the conditions of 30 °C and 20 kPa of TMP. Meanwhile, the effluent concentration of COD, NH4 +-N and SP all increased while OLR was changed from 1.0 to 3.0 kg COD/m3/day, and the effluent COD and NH4 +-N concentration except for SP could reach the B-level of Chinese “Wastewater quality standards for discharge to municipal sewers” when OLR was less than 3.0 kg COD/m3/day. This indicates that dewatered alum sludge-based aerobic membrane reactor is a promising bio-measure for treating high salinity wastewater.

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