Hybrid Membrane Process Research Articles

Advanced Treatment: Tackling Paracetamol with Fenton Oxidation and Membrane Hybrid Processes

Paracetamol (PCT) in aquatic environments has become a global concern due to its potential harm to humans and environments. However, conventional water treatment was only able to degrade PCT partially. It was necessary to treat PCT contaminated water with tertiary technologies in particular by combination approach, such as Fenton oxidation and membrane filtration process. This combined approach enabling mitigation of large chemical footprint and iron residue associated with Fenton oxidation, as well as reducing fouling tendency of the membrane. The aim of this study was to evaluate the PCT removal efficiency by hybrid technology Fenton oxidation and membrane filtration. The membrane performance during the filtration process was also analyzed. As an important parameter for Fenton process, concentration of H 2 O 2 /Fe 2+ with ratio of 1:0.5 resulted in optimal removal of 45% PCT in terms of COD removal. However, separation using flat sheet Polyethersulfone Ultrafiltration (UF) with constant flux of 120 L/m²·h resulted in insignificant of COD removal. Nevertheless, the UF process was able to remove up to 54% of Fe 2+ at pH in alkaline condition with 8.5. In addition, a decrease in membrane permeability down to 0.2 L/m²h/bar over time, according to the filtered specific volume during the UF process, indicates fouling of the UF membrane during the 120 minutes of filtration. While the combined approach does not show significant improvement in COD removal, it does help to reduce the chemical footprint of the process, which is an important factor for the applicability of the selected water treatment method.

Circular hybrid membrane process treating high-salinity ammonium-rich pharmaceutical wastewater

Ammonia-rich saline wastewater is a common byproduct of the pharmaceutical industry. Hollow fiber membrane contactors (HFMCs) show potential for NH3 recovery, enabling valuable product recycling. Our previous work indicated that excessive NaOH usage and increased salinity of the treated effluent are major setbacks when employing HFMCs for NH3 recovery from pharma wastewater. Therefore, finding alternative approaches to reduce chemical use and salinity is vital. This study demonstrates the integration of bipolar membrane electrodialysis (BMED) with HFMC for NH3 recovery, chemical recycling, and salinity reduction. This novel, highly circular concept was tested using real pharmaceutical wastewater. We varied the volume ratios between compartments to assess the BMED flexibility in attaining different treatment goals. BMED achieved over 90% salinity reduction and produced concentrated base and acid in all volume ratios tested, saving 70% of the NaOH required for pH increase before the HFMC step. The HFMC achieved over 98% NH3 recovery in two sets of five consecutive cycles, using either a BMED-generated base or NaOH. A preliminary economic analysis revealed a 47% reduction and 86% increase in expenses on chemicals and energy, respectively, compared to HFMC without BMED. Nevertheless, since the largest operating expense was the purchase of chemicals, integrating the BMED step reduced the overall operating expenses of the treatment by 33% (from $3.76 to $2.54 per kg N). The treated effluent’s quality allows discharge to conventional wastewater treatment plants, resulting in economic and environmental benefits. This work highlights the importance of innovative separation processes in advancing toward cleaner drug manufacturing.

Electrodeionization for Wastewater Reuse in Petrochemical Plants

This study investigated a hybrid membrane and electro-membrane separation process for producing demineralized water from tertiary petrochemical effluent, reusing it as feeding water for high-pressure boilers for steam generation. The effluents were treated in a pilot plant with a 1 m3 h−1 capacity by using a hybrid process of ultrafiltration (UF), reverse osmosis (RO), and electrodeionization (EDI). The physicochemical parameters of interest and maximum limits in industrial water were pre-determined by the industries. Operating parameters such as flow rate, pressure, percentage of recovery, and electric current were monitored, along with the frequency of chemical cleaning. The UF and RO systems operated with average permeate fluxes of 17 ± 4.06 L h−1 m−2 and 20.1 ± 1.9 L h−1 m−2, respectively. Under optimal operating conditions (flow rate of 600 L h−1, voltage of 22.2 ± 0.7 V, and electric current of 1.3 A), EDI produced high-quality water with an average electrical conductivity of 0.22 μS cm−1. Thus, the industrial water produced reached the quality required for reuse as make-up water for high-pressure boilers in the petrochemical industry. In addition, the specific energy consumption; the use of chemicals, spare materials, equipment; and labor costs were determined to support the technical feasibility study for implementing an industrial plant with a 90 m3 h−1 producing capacity. This resulted in a cost of USD 0.64 per cubic meter of demineralized water produced, a cost similar to values reported in the literature.

The analytic hierarchy process method to design applicable decision making for the effective removal of 2-MIB and geosmin in water sources

Numerous utilities encounter issues with taste and odor that alter the public’s impression of the safety of drinking water. The creation of certain components in water naturally due to global climate change is another source of taste and odor components, in addition to industrial emissions. Geosmin and 2-methylisoborneol (2-MIB), both of which are generated by blue-green algae and actinomycetes, are two substances that contribute to the musty and earthy smells in drinking water sources. Unfortunately, current conventional treatment plants only partially remove 2-MIB and geosmin. Therefore, to protect the environment and public health, more up-to-date or optimized treatment methods should be applied to outdated treatment facilities. Best treatment practices, evaluation standards, and decision-making approaches, however, are still shrouded in mystery. The goal of this study was to identify the most effective treatment options for 2-MIB and geosmin. By using the analytical hierarchy process (AHP), a total of 22 assessment criteria were found and prioritized. A thorough literature search led to the identification of potential treatment options, and their effectiveness was evaluated. These options and priority rankings were decided upon using AHP in the decision-making process. Advanced oxidation techniques came out on top in the final priority ranking, followed by membrane filtering, adsorption, oxidation, hybrid processes, and traditional treatment methods. The applied analytical decision techniques may also be used to choose the optimal treatment options, even though the results are particular to 2-MIB and geosmin.

Efficiency of fenton oxidation and membrane hybrid processes for paracetamol removal in seawater

Traces of Paracetamol (PCT) as a micropollutant in the environment, particularly in seawater (SW), have become a global concern in recent years due to the toxicity effect on humans and environment. Due to special characteristics, conventional wastewater treatment plants are able to degrade PCT partially. Therefore, an alternative treatment was necessary to treat PCT substance. Homogeneous Fenton oxidation is an efficient process to degrade PCT at various levels. Nevertheless, separation of dissolved iron by-products in the effluent caused a problem. Combination of Fenton oxidation and ultrafiltration treatment presents a promising opportunity as one of the alternative treatments for PCT removal across aqueous matrices and removal of iron residue. Despite promising, information related to combine Fenton and membrane process was lacking. Therefore, this study aims to evaluate the efficiency of the hybrid processes to remove PCT, represented in Chemical Oxygen Demand (COD), for both distilled water (DW) and seawater. In this study, crucial parameter Fenton’s reagent with H2O2/Fe2+ ratio (w/w) was observed. In the DW matrix, optimal 1:0.5 ratio resulted 45% COD removal, whereas 1 :1 ratio exhibited 37% COD removal in SW. Flat sheet Polyethersulfone (PES) with pore size of 30 nm and 7 nm (50 kDa) membrane was employed with a constant flux of 120 L/m²·h. A lack of contribution of COD removal in DW and 37% in SW was observed during the ultrafiltration process, respectively. Furthermore, 54% and 92% removal of Fe2+ residue was observed during ultrafiltration at adjusted pH 8.5 in both water matrices using different membrane pore sizes, respectively.

Application of ultrafiltration technology in drinking water industry of China: A comprehensive assessment of hybrid membrane processes

Abstract Over the last decades, ultrafiltration (UF) has been and will continue to play an important role in the Chinese drinking water industry. The hybrid membrane processes have been emerging as promising alternatives to traditional treatment processes. This review paper offers a thorough overview of the current status of UF technology in the drinking water industry in China, while also evaluating the landscape of different hybrid membrane processes. The paper conducts statistical analysis on the projects operational between 2004 and 2022; and those currently under construction. This analysis accentuates the evolution of scale and capacity, geographical distribution characteristics, and the driving forces. Furthermore, the characteristics and application scenarios of several hybrid membrane processes are emphatically described, including direct UF, gravity-driven membrane process, coagulation-UF, activated carbon-UF, medium-flow process, long-flow process, and double-membrane process. A granular dissection of UF membrane market distribution follows, including an incisive comparison between submerged and pressurized UF membrane systems. Finally, the potential trajectory of UF in the Chinese drinking water industry is prospected. UF applications have grown significantly in China's drinking water industry, with the dominance of medium- and long-flow membrane processes. UF technology will contribute to future decentralized water supply.

Performance of biological ion exchange resin and gravity-driven ceramic membrane hybrid process for surface water treatment

In this study, the performance of a biological ion exchange (BIEX) resin and gravity-driven ceramic membrane (GDCM) filtration hybrid process in terms of membrane permeate quality, flux, and membrane biofilm characteristics during river water treatment for drinking water was investigated. The hybrid process results were compared with those of the GDCM process without the BIEX pre-treatment. Three types of previously synthesized microfiltration membranes were used: M1 (100 wt% kaolin), M2 (75 wt% kaolin + 25 wt% alumina), M3 (50 wt% kaolin + 50 wt% alumina), and M4 (commercial ceramic microfiltration membrane). In terms of permeate quality, the BIEX column removed approximately 74 % of the dissolved organic carbon (DOC) compared with the influent water, followed by 27 % DOC removal using M3 compared with the BIEX column effluent on day 65 (6,240 BV), which was mainly due to the removal of humic and fulvic acids. BIEX removed turbidity of the influent water from 2.20 NTU to 0.77 NTU, which was further decreased to 0.09 NTU by membranes. The maximum stabilized flux of the membranes was approximately 5.7 LMH, which was almost doubled compared to GDCM without pre-treatment. The membrane biofilm showed lower thickness and roughness in the hybrid process than that in GDCM without pre-treatment. Higher extracellular polymeric substance (EPS) concentration and biological activity were observed for M3, the membrane with the highest stabilized flux and highest DOC removal efficiency. The results indicate that the hybrid BIEX + GDCM is a robust, high-performance, and easy-to-use process that can increase the flux and permeate quality of GDCM systems.

Application of different treatment systems for boron removal from industrial wastewater with extremely high boron content

The aim of the study is purification and environmental management of boron containing industrial wastewater wastewaters comparing the efficiency of chemical precipitation and membrane filtration systems on the removal of boron at high concentrations from wastewater coming from boric acid production process and ground water. In order to eliminate adverse effects and find optimum treatment system, chemical precipitation, electrocoagulation and reverse osmosis processes have been studied. Different chemical precipitants such as poly aluminum chloride (PACl), lime, calcium chloride (CaCl2) and barium chloride (BaCl2) and hydrogen peroxide as oxidant were used. When solution pH was adjusted at 10, boron removal increased to 99.5 %. With application of electrocoagulation, 9 % of SO42-, 80 % of Si and 45 % of B were removed from spring water. At membrane-system, single and double pass BWRO/SWRO membrane system operations were carried out in order. Boron-removal increased 98 % by increasing pH up to 10, and DP-SWRO membranes system at 10-pH was found to be the best system. Obtaining a sufficient result for boron removal from spring water, a hybrid membrane process which contains an electrocoagulation process as a pre-treatment method and a double pass RO membrane system has been developed as an attractive technology.

Advanced Treatment of the Municipal Wastewater by Lab-Scale Hybrid Ultrafiltration

In this study, hybrid ultrafiltration which involves adsorption onto activated carbon and/or coagulation was tested for the removal of ibuprofen, caffeine and diclofenac from the municipal wastewater treatment plant effluent (c0 = 2–3 µg/L). Ultrafiltration was tested in combination with powdered activated carbon dose of 5 mg/L separately or with coagulants (FeCl3, dose 4 mg Fe (III)/L and, natural coagulant isolated from bean seeds, dose 33 µL/L). In addition to the removal of organic micropollutants, the removal of As, Cr, Cu and Zn was also tested (c0~100 µg/L). The research was conducted on a laboratory pilot plant (capacity 30 L/h, in-out dead-end filtration, flux of 80 L/m2h). The best results were obtained for caffeine when adsorption on PAC is combined with a FeCl3 (removal efficiency 42–87%). The addition of a natural coagulant did not show benefits for the removal of organic micropollutants compared to the other tested processes, but both coagulants had similar effects on the content of metals and As Hybrid membrane processes proved to be the most efficient for Zn (44–87%) and Cr (33–87%) removal. The lowest efficiency was determined for As (˂19%). Ultrafiltration with PAC and coagulants removed 5–33% of effluent organic matter, depending on the type of coagulant; 57–87% of total nitrogen and PAC/FeCl3/UF was also partially effective for removing total phosphorus (11–39%).

A Comprehensive Review on Pulp and Paper Industries Wastewater Treatment Advances

The pulp and paper industry generates vast amounts of wastewater, and its character heavily depends on various factors (raw material, the undertaken process, the final product, etc.). The wastewater from this sector, which originates from several sources in each mill and are mostly combined, is polluting and hazardous. This paper presents a state-of-the-art review of the physical, chemical, biological, and advanced hybrid treatment techniques, concerning their effectiveness in removing specific pollutants, namely, chemical oxygen demand, lignin, color, and adsorbable organo-halogens. Throughout the manuscript, at the end of each section, a conclusive comparison has been presented and the proper method is introduced. Furthermore, numeric data regarding the effectiveness of each technique toward each pollutant are gathered from the literature and are available in the Supporting Information of the paper. Biological treatment processes using anaerobic–aerobic treatment mostly cure organic biodegradable contaminants (75–90% COD removal). Moreover, biological treatment using a consortium of microorganisms can potentially increase color removal efficiency (from 65 to 97%). Hybrid treatment is also among the candidates for color removal. To treat complex matters (lignin and AOX), physical and chemical treatments have shown promising performance, but they are generally expensive and impractical to treat huge amounts of wastewater. For the treatment of high molecular weight contaminants (lignin) advanced oxidation processes (AOPs), including ozonation and Fenton-based treatment, have shown great performance (90–99%); however, they are limited due to their maintenance and operation costs. To overcome these challenges, source separation of the wastewater streams in the pulp and paper industry is recommended. AOPs or membrane technologies or hybrid processes are suggested for the bleaching effluent (80% AOX removal), which is relatively low in amount, and a combination of conventional treatment processes would be preferred to treat wastewater streams that are more biodegradable. The biological performance can also be enhanced using granular activated carbon on the sequence. Finally, for treating black liquor, adsorption processes have proven to be the prime candidate.

Hybrid membrane process for water treatment: a short review

Abstract Water shortage is one of the most difficult issues confronting people all over the world. Rapid urbanization and water scarcity necessitate immediate action to improve sustainable water management without jeopardizing global socioeconomic growth. Thus, conventional water treatments are implemented for the purpose of eradicating various pollutants in wastewater. Traditional water treatment methods, whether in water treatment facilities or reverse osmosis (RO) plants, have run across a number of roadblocks that have significantly hampered their performance and efficiency. Integrating the membrane process with other remediation technologies in a hybrid process is a novel technique to improve contaminant extraction efficiency for our target streams. This process is termed the hybrid membrane process (HMP). On this aspect, this paper would highlight the benefits of using the HMP compared to conventional methodologies and their applications conducted in various sectors around the world. Some case studies are also reviewed illustrating its cost analysis in comparison to conventional methodologies accentuating the merits of using HMPs.

A Novel Hybrid Membrane Process Coupled with Freeze Concentration for Phosphorus Recovery from Cheese Whey.

The ever-increasing demand for phosphorus fertilisers for securing global food production, coupled with finite phosphate rock reserves, is one of the emerging problems in the world. Indeed, phosphate rock is listed as an EU critical raw material, triggering attention to find an alternative source to substitute the use of this limited resource. Cheese whey, characterized by a high content of organic matter and phosphorus, represents a promising feedstock for phosphorus recovery and recycling. An innovative application of a membrane system coupled with freeze concentration was assessed to recover phosphorus from cheese whey. The performances of a microfiltration membrane (0.2 µm) and an ultrafiltration (200 kDa) membrane were evaluated and optimized under different transmembrane pressures and crossflow velocities. Once the optimal operating conditions were determined, a pre-treatment including lactic acid acidification and centrifugation was applied to increase the permeate recovery. Finally, the efficiency of progressive freeze concentration for the treatment of the permeate obtained from the optimum conditions (UF 200 kDa with TMP of 3 bar, CFV of 1 m/s and lactic acid acidification) was evaluated at specific operating conditions (-5 °C and 600 rpm of stirring speed). Finally, 70% of phosphorus could be recovered from cheese whey using the coupled technology of the membrane system and freeze concentration. A phosphorus-rich product was obtained with high agronomic value, which constitutes a further step towards establishing a broader circular economy framework.

Life cycle assessment of sericin recovery from silk degumming wastewaters

Sericin is a silk protein discarded with silk degumming wastewater. Life cycle assessment of sericin recovery from silk degumming wastewater was conducted considering two scenarios; base scenario (no recovery), and sericin recovery with membrane hybrid processes. Base scenario consists of silk degumming and treatment of degumming wastewater. The recovery scenario consists of sericin recovery with the process train; silk degumming, sedimentation, nanofiltration (NF), precipitation and lyophilization. Spray drying was also considered as an alternative to the precipitation and lyophilization. The system boundary was set as cradle to grave and the functional unit was selected as 1 kg of sericin. The recovery scenarios had much higher environmental impacts as compared to the base scenario. In terms of kg CO2 equivalence, the impact of the recovery scenarios on climate change (global warming effect) was found to be approximately 2000–2650 times higher than the base scenario. In recovery scenario, endpoint impact score for climate change was as high as 50%, followed by natural resources (34%) and human health impacts (15%). The use of centrifugation + lyophilization option was found to cause 40%–50% more impacts compared to the spray drying option. The highest impact was for the nonrenewable energy impact category, followed by the global warming category. NF and sericin degumming were the processes with highest environmental impacts.

Performance of a novel granular activated carbon and gravity-driven membrane hybrid process: Process development and removal of emerging contaminants

In this study, a novel granular activated carbon (GAC) gravity-driven membrane (GDM) hybrid system with a ceramic membrane was developed for the production of high quality water. The operational performance in water permeability; removal of organic matter; and contaminants of emerging concern (CECs) including microplastics, larvae, and perfluorinated compounds (i.e., perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid(PFOS)) was evaluated. The experimental results indicate that the GAC-GDM hybrid system can overcome the limitations of the GAC (i.e., low rejection efficiency of particulates) and GDM (i.e., low rejection efficiency of organics) processes. The GDM process showed higher removal rates of microplastics and larvae than the GAC process (i.e., 77.9% and 100% vs. 16.6% and 70%, respectively), and the GAC process exhibited higher removal rates of organic matter and perfluorinated compounds (PFOA and PFOS) than the GDM process (i.e., 54.8%, 90.9% and 99.1% vs. 17.6%, 23% and 31.8%, respectively). In the GAC-GDM hybrid system, stable water flux was observed with the efficient removal of CECs and organic matter during operation. This study implies that the GAC-GDM system can be used as a distributed water treatment system in remote areas such as islands and mountains because the GAC-GDM system is able to minimize the operation scale.

Management of reject streams from hybrid membrane processes applied to phenolic compounds removal from olive mill wastewater by adsorption/desorption and biological processes

This work studies the valorisation of the concentrates obtained through membrane processes for the purification of olive oil washing wastewater (OOWW). The adsorption with resins/desorption process, followed by a biological treatment with sequencing batch reactor SBRs. Three different wastewater samples were treated: an ultrafiltration reject stream (UF-R), with a high organic load and low content of phenolic compounds; a nanofiltration reject stream (NF-R), which rich in phenolic compounds and with medium organic load; a stream concentrated by forward osmosis (FO-C) with high organic content and concentration of phenolic compounds. Through the adsorption/desorption process, it was possible to recover 90 % and 73 %, which corresponds to 1.69 and 1.66 g∙L−1 of the total phenolic compounds reject streams of NF-R and FO-C, respectively. With the SBRs, it was possible to eliminate around 80 % of the organic matter present in the effluent of adsorption, and also 90 % of the remaining phenolic compounds in the case of UF-R. The results obtained are promising since, on the one hand, a high recovery of phenolic compounds was achieved and, on the other hand, a large part of the organic matter of the remaining streams after adsorption was eliminated. In this way, a solution for the management of the membrane reject streams is proposed, allowing a circular economy in the wastewater treatment of olive oil processing.

Potential for water and metal recovery from acid mine drainage by combining hybrid membrane processes with selective metal precipitation

Acid mining drainage has a serious impact on the environment. Forward osmosis allows the concentration of acid mine waters to favor the formation of enrichment sludges and subsequent selective metal precipitation. In this work, a methodology was proposed to treat mining effluents from the Iberian Pyrite Belt. Forward osmosis experiments were performed using different osmotic pressures from 0.5M to 2.5M NaCl to evaluate water fluxes and recovery. The water recovery obtained was in the range of 50-80%, and the flux remained above 5 (L•m−2•h−1). Four combined processes were modelled to determine the feasibility of eliminating water and precipitating metals. Furthermore, a new hybrid membrane process was proposed to recover at least 75% of water with recovery yields of Al, Fe, Cu, Zn and Mn of greater than 70%. A water production cost of 2.01 $/m3 and a specific energy consumption of 8.03 kWhe/m3 were estimated for the hybrid process.

Performance of a hybrid process integrating PAC adsorption with ceramic membrane ultrafiltration for drinking water treatment

Membrane separation technologies have broad application prospects in water treatment. Compared with polymeric membranes, ceramic membranes have higher stability for long-term operation in practical applications. Coupling ceramic membranes with other water treatment processes is an effective way to improve membrane treatment effect and alleviate membrane fouling. This study evaluated the water purification efficiency and membrane fouling behaviors of powdered activated carbon (PAC), flat-sheet ceramic membranes and their hybrid process in treating model organic pollutants and natural water. Results showed that the PAC-ceramic membrane hybrid process could alleviate the membrane fouling caused by humic acid but aggravate that caused by sodium alginate. Addition of PAC notably improved the removal performance of the ceramic membrane for organic matters in natural water as well as pharmaceutical and personal care products, and effectively controlled membrane fouling. The PAC adsorption obviously reduced the irreversible fouling of the ceramic membrane under multi-cycle operation. This study can provide a reference for the practical application of ceramic membranes in drinking water treatment.

Economic Benefits of Waste Pickling Solution Valorization.

An integrated hybrid membrane process, composed of a diffusion dialysis (DD), a membrane distillation (MD) and a reactive precipitation unit (CSTR), is proposed as a promising solution for the valorization and onsite recycling of pickling waste streams. An economic analysis was performed aiming to demonstrate the feasibility of the developed process with a NPV of about EUR 40,000 and a DPBP of 4 years. The investment and operating costs, as well as the avoided costs and the benefits for the company operating the plant, were analyzed with an extensive cost tracking exercise and through face-to-face contact with manufacturers and sector leaders. A mathematical model was implemented using the gPROMS modelling platform. It is able to simulate steady state operations and run optimization analysis of the process performance. The impact of key operating and design parameters, such as the set-point bath concentration and the DD and MD membrane areas, respectively, was investigated and the optimal arrangement was identified. Finally, operating variables and design parameters were optimized simultaneously in a nonlinear framework as a tradeoff between profitability and environmental impact. We show how the integration of new technologies into the traditional pickling industry could provide a significant benefit for the issues of process sustainability, which are currently pressing.

Comparison of diverse direct and hybrid membrane processes for nitrate removal from brackish water

Comparison of diverse direct and hybrid membrane processes for nitrate removal from brackish water

Evaluation of hybrid pressure-driven and osmotically-driven membrane process for non-thermal production of apple juice concentrate

This study investigates the potential of hybrid membrane processes including microfiltration (MF), ultrafiltration (UF) and forward osmosis (FO) for non-thermal concentration of apple juice. The process performance and characteristics (physicochemical properties, nutritional and aroma components and microbiological quality) of apple juice were studied. The clarity of apple juice was significantly promoted as pore size of membrane reduced. MF and UF can also ensure microbiological safety in pre-treated apple juice. According to its efficiency of filtration as well as performance of simultaneous clarification and cold-sterilization, 0.22 μm MF membrane was identified as the optimal membrane for the pre-treatment. The pre-treated apple juice can be concentrated up to 65°Brix by subsequent single stage FO. FO retained nutritional and volatile compounds of apple juice while significant reductions were found in the juice concentrated by vacuum evaporation. Hybrid MF-FO can be a promising non-thermal technology to produce apple juice concentrate with high quality.