Ultrafiltration Treatment Research Articles

Ultrafiltration technology with a ceramic membrane for reactive dye removal: Optimization of membrane performance

An ultrafiltration (UF) ceramic membrane was used to decolorize Reactive Black 5 (RB5) solutions at different dye concentrations (50 and 500mg/L). Transmembrane pressure (TMP) and cross-flow velocity (CFV) were modified to study their influence on initial and steady-state permeate flux (Jp) and dye rejection (R). Generally, Jp increased with higher TMP and CFV and lower feed concentration, up to a maximum steady-state Jp of 266.81L/(m2h), obtained at 3bar, 3m/s and 50mg/L. However, there was a TMP value (which changed depending on operating CFV and concentration) beyond which slight or no further increase in steady-state Jp was observed. Similarly, the higher the CFV was, the more slightly the steady-state Jp increased. Furthermore, the effectiveness of ultrafiltration treatment was evaluated through dye rejection coefficient. The results showed significant dye removals, regardless of the tested conditions, with steady-state R higher than 79.8% for the 50mg/L runs and around 73.2% for the 500mg/L runs.Finally response surface methodology (RSM) was used to optimize membrane performance. At 50mg/L, a TMP of 4bar and a CFV of 2.53m/s were found to be the conditions giving the highest steady-state Jp, 255.86L/(m2h), and the highest R, 95.2% simultaneously.

Membrane filtration and sonication for industrial wastewater reuse

This paper presents an experimental study aimed at estimating the efficiency of the innovative process of ultrafiltration (UF) combined with sonication (Son.) for the refinement of treated effluent to be reused in wet textile processes. Such a novel approach, which has not yet been employed on a full industrial scale, has been experienced at pilot scale on the secondary effluent of the Baciacavallo wastewater treatment plant (WWTP), which treats part of the effluent from one of the largest textile industry districts in Italy. The combined treatment efficiency was assessed both on ozonated and non-ozonated Baciacavallo secondary effluent. The membrane filtration process was optimized in terms of running time, backwash, chemical addition and cleaning procedures. The sonication treatment was optimized on laboratory-scale with synthetic solutions (demineralized water added with dyestuffs) in terms of hydroxyl radicals formation rate, frequency, acoustic power, hydrogen peroxide addition, contact time and pH. The optimal conditions have been applied on the pilot-scale sonicator which was used in combination with the UF treatment. According to the experimental results, the best configuration within the Baciacavallo WWTP was the sonication of non-ozonated wastewater followed by the UF. The combined treatment guaranteed the compliance with the target values for wastewater reuse in wet textile industries. This study is part of the Research Project PURIFAST (Purification of industrial and mixed wastewater by combined membrane filtration and sonochemical technologies) LIFE + ENV/IT/000439.

Coagulation and UF treatment of pulp and paper mill wastewater in comparison

Abstract A study using coagulation-flocculation and ultrafiltration (UF)methods for pulp and paper mills’ wastewater (WW)was carried out. The reduction efficiencies of turbidity and chemical oxygen demand (COD), the removal efficiency of total suspended solids (TSS) and absorbance at 254 nm were the main evaluating parameters. Using coagulation-flocculation, the efficiencies of alum and polyaluminum chloride (PACl)were studied, when used alone and when coupled with flocculant aids. During the coagulation-flocculation process, use of a single coagulant, the coagulant dosage, and the pH, play an important role in determining the coagulation efficiency. At the optimum PACl dosage of 840 mg L−1 and optimum pH of 9.0, turbidity reduction was found to be 94.5%. A combination of inorganic coagulant and flocculant, or polymer was applied, in which PACl was used coupled with the polyelectrolytes Organopol WPB20 and WPB40. PACl coupled with Organopol WPB20 by optimal pH 9 gave a 98.3% reduction of turbidity, 91.9% removal of TSS, and a 60.2% reduction in COD. Ultrafiltration trials were carried out on a pilot scale. A tubular module was used with ceramic membrane. This membrane is a multi-channel membrane with an active surface layer made of Al2O3 and ZrO2. Within the acidic range, the turbidity and TSS were removed at above 99%.

Evaluation of effluent organic matter fouling in ultrafiltration treatment using advanced organic characterisation techniques

Membrane fouling remains an operational challenge in the ultrafiltration (UF) membrane treatment of wastewater effluent and research is on-going to improve understanding of the organic character of foulants. Two advanced organic characterisation techniques that have potential to lend insight into membrane fouling are size exclusion chromatography with organic carbon, UV 254 and nitrogen detection (LC-OCD) and fluorescence excitation–emission matrix (EEM) spectroscopy. In this study, UF treatment was undertaken for five tertiary wastewater effluents. The total hydraulic resistance was determined as well as that contributed by foulant layers fractionated by rinsing, backwashing and chemically desorbing. Organic characterisation for UF feed samples, permeates and each foulant layer was then performed using LC-OCD and FEEM spectroscopy with the aim of improving understanding of the character of foulants present in effluent organic matter (EfOM) and to determine the potential for the use of FEEM spectroscopy as a foulant indicator in such systems. It was determined that the biopolymer fraction was most significantly reduced on UF treatment, as anticipated due to its high molecular size. This was supported by the observation that the majority of the foulant layer comprised predominantly protein-enriched biopolymers (38–60% of total foulant layer DOC) that could be removed by rinsing. The resistance attributed to rinsing was directly related to the combined DOC concentration associated with proteins and low molecular weight neutral compounds as defined by LC-OCD analysis. Furthermore, tyrosine-like fluorescence intensity ( λ ex/em = 250/304 nm) of both the rinsing solutions and UF feed samples showed good correlation with associated hydraulic resistance for EfOM originating from domestic wastewater, suggesting that fluorescence has potential to be used as a foulant indicator for these systems.

Early Ultrafiltration May Reduce Length of Hospital Stay for Decompensated Heart Failure

Heart Failure Society of America and American College of Cardiology/American Heart Association (ACC/AHA) guidelines support use of ultrafiltration (UF) as a treatment for patients with heart failure who present with volume overload [1] [2]. Studies have shown reduced length of hospital stay [3] and reduced readmission rates [4] with ultrafiltration in comparison to standard therapy. Early initiation of UF therapy may reduce length of hospital stay. Data were extracted by retrospective chart review of admissions with primary diagnosis of decompensated heart failure including right and left ventricular failure and requiring UF. Institutional Review Board exemption was granted. All UF treatments were prescribed and managed by the Heart Failure Management Program practitioners at St Luke's Hospital and Health Network, Bethlehem, PA, using Aquapheresis by the Aquadex system between December 2008 and November 2010. One hundred eighty UF therapies provided data, mean age ± standard deviation [SD] was 73.7 ± 11.1 years); 124 (68.9%) were aged >70 years and 103 (57.2%) were male. Among the 180 UF therapies, data was compared between those initiated within the first 24 hours of admission (101) vs. those initiated between 24 and 72 hours (34). UF therapies initiated after 72 hours were excluded. Both groups were demographically similar with 61% males and mean age of 74 years. Multiple parameters including serum creatinine, BUN, electrolytes, UF duration, UF volume, change in weight, length of hospital stay and readmission rates were compared. The mean length of stay ± standard deviation [SD] for early UF (within 24 hours) was 5.5 +/- 5.0 days in comparison to 12.2 +/- 11.4 days for later UF (24 to 72 hours). Statistical analysis using Welch's unpaired t test showed the difference to be statistically significant (P=0.002). Among patients who qualify for ultrafiltration therapy, early initiation reduces length of hospital stay.

Is There a Necessity for Individual Blood Water Corrections when Conductivity-Based Access Blood Flow Measurements Are Made?

Background/Aims:Access blood water flow rate (Qaw) can be measured during hemodialysis using an online effective ionic dialysance (EID) methodology. Fresenius employ this methodology in their 2008K dialysis machine. The machine computer converts Qaw to an access blood flow rate (Fresenius Qa) using a generic blood water constant (BWC). We wished to validate this BWC. Methods: 18 patients had Fresenius Qa measurements using the EID and these were compared with a ‘gold standard’ ultrasound dilution methodology (Transonic Qa). Qa values were also obtained by removing the BWC from Fresenius Qa values to obtain the Qaw and recorrecting it with individualized patient factors using hematocrit and total protein values (HctTp Qa). The measurements were repeated after 1 h. Results:There were no significant differences between Fresenius and Transonic, nor between HctTp and Transonic Qa values (p > 0.17). There were strong correlations between both sets of values (r > 0.856; p < 0.001). There was a significant correlation between the pairs of Transonic Qa values (r = 0.823; p < 0.007), but not for Fresenius Qa pairs (r = 0.573; p > 0.07). It was surmised that the BWC was not valid post-dialysis. Conclusion:The generic BWC is comparable to individualized blood water correction factors when Qa measures are made early in dialysis and prior to ultrafiltration treatment.

Chelating–Ultrafiltration Treatment of Some Heavy Metal Ions in Aqueous Solutions by Crosslinking Carboxymethyl Modified Cornstarch

Crosslinking carboxymethyl starch (CCMS) powder of degree of substitution (DS) 0.43–0.59 was prepared by the process of two steps of alkali addition synthesis. The technique of powder coupling with ultrafiltration was used to absorb Cu2+, Zn2+, Ni2+, Pb2+, and Cd2+ from aqueous solutions. FTIR was used to demonstrate the successfully grafting of carboxymethyl groups, and the technique of microwave plasma torch atomic emission spectrometer was applied in rapid determination of the aforementioned heavy metals ions. The results revealed that the removal sequence of heavy metal ions followed the order of Pb2+>Cu2+>Cd2+>Zn2+>Ni2+. By assistant of diethylene triamine penlaacetic acid, the quaternary system of Pb2+/Ni 2+/Cd2+/Cu2+ mixture solution could have the ideal separation. Besides, the influence of pH, ζ potential, DS value, and membranes molecular weight cut-off on removal of 20 mg L−1 Pb2+ or Ni2+ was also investigated.

Micellar enhanced ultrafiltration process for the treatment of olive mill wastewater

Olive mill wastewater (OMW) is an important environmental pollution problem, especially in the Mediterranean, which is the main olive oil production region worldwide. Environmental impact of OMW is related to its high organic load and particularly to the phytotoxic and antibacterial action of its phenolic content. In fact, polyphenols are known as powerful antioxidants with interesting nutritional and pharmaceutical properties. In the present work, the efficiency of OMW Micellar Enhanced Ultrafiltration (MEUF) treatment for removal and concentration of polyphenols was investigated, using an anionic surfactant (Sodium Dodecyl Sulfate salt, SDS) and a hydrophobic poly(vinyldene fluoride) (PVDF) membrane. The effects of the process experimental conditions on the permeate flux were investigated, and the secondary membrane resistance created by SDS molecules was evaluated. The initial fluxes of OMW processing by MEUF using SDS were 25.7 and 44.5 l/m2 h under transmembrane pressures of 3.5 and 4.5 bar, respectively. The rejection rate of polyphenols without using any surfactant ranged from 5 to 28%, whereas, it reached 74% when SDS was used under optimum pH (pH 2). The MEUF provides a slightly colored permeate (about 88% less dark), which requires clearly less chemical oxygen demand (COD) for its oxidation (4.33% of the initial COD). These results showed that MEUF process can efficiently be applied to the treatment of OMW and for the concentration and recovery of polyphenols.

Recycle of waste backwash water in ultrafiltration drinking water treatment processes

Research Article| June 01 2011 Recycle of waste backwash water in ultrafiltration drinking water treatment processes Stephanie Leah Gora; Stephanie Leah Gora 1Department of Civil and Resource Engineering, Dalhousie University, 1360 Barrington St, Bldg D, Rm D215, Halifax, Nova Scotia B3J 1Z1, Canada Search for other works by this author on: This Site PubMed Google Scholar Margaret Evelyn Walsh Margaret Evelyn Walsh 1Department of Civil and Resource Engineering, Dalhousie University, 1360 Barrington St, Bldg D, Rm D215, Halifax, Nova Scotia B3J 1Z1, Canada E-mail: mwalsh2@dal.ca Search for other works by this author on: This Site PubMed Google Scholar Journal of Water Supply: Research and Technology-Aqua (2011) 60 (4): 185–196. https://doi.org/10.2166/aqua.2011.050 Article history Received: August 16 2010 Accepted: November 16 2010 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Cite Icon Cite Permissions Search Site Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsThis Journal Search Advanced Search Citation Stephanie Leah Gora, Margaret Evelyn Walsh; Recycle of waste backwash water in ultrafiltration drinking water treatment processes. Journal of Water Supply: Research and Technology-Aqua 1 June 2011; 60 (4): 185–196. doi: https://doi.org/10.2166/aqua.2011.050 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex In drinking water treatment, ultrafiltration (UF) membrane systems are generally operated at 90 to 95% recovery with production losses resulting from waste residual streams such as backwash water and clean-in-place (CIP) liquid residuals. In drought-prone regions, it may be desirable to apply alternative UF plant design configurations to increase recovery rates and minimize water loss. This approach could consist of adding a secondary stage UF membrane for treatment of first stage UF residuals, or recycling the first stage UF waste residuals by blending a percentage of the backwash water with the raw water at the front of the treatment train. For small systems, the second option may present a more cost-effective solution. The overall objective of this research project was to investigate the potential impacts to UF permeate water quality and coagulation pretreatment efficacy in a bench-scale submerged UF membrane system operating with and without waste backwash water recycle. The results of the study showed that blending 10% waste backwash water with raw water did not negatively impact UF permeate water quality. The results also demonstrated that recycling waste backwash water prior to coagulation–UF treatment may improve organic removal and reductions in neat coagulant dosage may be possible to achieve specific DBP precursor removal targets. coagulation, filter backwash water, natural organic matter, ultrafiltration This content is only available as a PDF. © IWA Publishing 2011 You do not currently have access to this content.

Application of membrane technology on semiconductor wastewater reclamation: A pilot-scale study

Wastewater discharged from semiconductor industry contains high turbidity and conductivity. When membrane systems are used for semiconductor wastewater reclamation without pretreatment, membranes will soon be clogged by the nano-size particles. In this pilot-scale study, a three-stage system has been developed for semiconductor wastewater reclamation. This system (flow = 5 m 3 d − 1 ) contained fiber ball (material: polypropylene, diameter = 25 mm) filtration (FF) followed by ultrafiltration (UF) and reverse osmoses (RO) units. The FF was installed as a pretreatment unit (first stage) for particle removal. Spiral wound (SW) UF (material: polyethersulfone) and RO membrane (material: polyamide) were applied in the second and third treatment stages, respectively. Up to 95.8% of suspended solid (SS) could be removed after the pretreatment by FF system with an 88 m hr − 1 filtration velocity. More than 95% of the remaining turbidity can be further removed after the following UF treatment (turbidity dropped from 30 to below 0.6 NTU). After the treatment by RO unit, the effluent conductivity, turbidity, and total dissolved solid dropped to below 69.2 μS cm − 1 , 0.06 NTU, and 53.5 mg L − 1 , respectively. Knowledge obtained from this study will be useful in designing the three-stage FF and UF/RO system for practical application.

THE EFFECT OF PROCESS VARIABLES FOR PRODUCTION OF COBIA (RACHYCENTRON CANADUM) SKIN GELATIN HYDROLYSATES WITH ANTIOXIDANT PROPERTIES

ABSTRACT Acid-treated cobia (Rachycentron canadum) skin was extracted in a retort (121C) to obtain retorted skin gelatin hydrolysates (RSGHs) containing antioxidant peptides with noticeable antioxidant properties. To improve the antioxidant activity of cobia RSGHs, five processing factors including alkali concentration, alkali pretreatment time, phosphoric acid concentration (PC), water/skin ratio (WS) and retorting time (RT) in RSGH production were screened using a fractional factorial design to identify critical factors. It indicated that PC, WS and RT had significant effects on α,α-diphenyl-β-picrylhydrazyl (DPPH) scavenging by RSGHs. Subsequently, the optimization of PC, WS and RT on the DPPH scavenging of RSGHs was studied using a central composite design to collect data that resulted in a response surface modeling. The highest value for the predicted DPPH scavenging (10 mg/mL RSGH) was 73.63% (PC = 6.5%, WS = 1 and RT = 180 min), and it exhibited 39.9% more scavenging of DPPH than that of original RSGH. PRACTICAL APPLICATIONS Recently, a number of studies indicated that peptides derived from different protein hydrolysates can act as potential antioxidants. Fish proteins possess high availability for us, and their hydrolysates might be used as a good source of antioxidants. Fish skin gelatin may provide an alternative source for food-grade gelatin because the amount of the skin waste from the fish processing industry is considerably large. No enzymatic hydrolysis or ultrafiltration treatments are needed; the antioxidant cobia retorted skin gelatin hydrolysates (RSGH) can be produced by thermal hydrolysis. Besides, the degree of thermal hydrolysis (121C) had significant effects on the α,α-diphenyl-β-picrylhydrazyl scavenging and lipid peroxidation inhibition of cobia RSGH. Moreover, we identified the critical processing variables in the RSGH making and suggested the optimized condition for the antioxidant RSGH production. The edible and water-soluble cobia RSGH is considered a potential candidate to develop natural antioxidants and food supplements.

High-yields heterologous production of the novel Aspergillus fumigatus elastase inhibitor AFUEI in Aspergillus oryzae

AFUEI, an elastase inhibitor produced by Aspergillus fumigatus strongly inhibits the elastolytic activity of A. fumigatus etc. To purify AFUEI, we constructed a strain that overproduces AFUEI by introducing the gene encoding AFUEI (Genbank accession no. AB546725) under control of the amyB promoter into the heterologous host Aspergillus oryzae. A. oryzae TF-4 displayed strong elastase inhibitory activity and produced considerably more AFUEI than that of A. fumigatus. Furthermore, AFUEI could be purified using culture broth and single ultrafiltration (UF) treatment, allowing for the effective production of AFUEI for use in clinical trials.

Differences in degradation kinetics for sonolysis, microfluidization and shearing treatments of chitosan

AbstractSolution concentration, temperature, reaction time and use or non‐use of concurrent ultrafiltration treatment for fragment removal are factors that affect the degradation rate constant in sonolysis, microfluidization and shearing treatments. The cause of these operation conditions and their effect on chitosan degradation rate constant were compared. Different operation conditions for each treatment resulted in various solution viscosities, ease of dissipation of cavitation, entanglement and stretching, in turn resulting in different rates of effectiveness of degradation by different degradation mechanisms. A rationale for applying these physical methods in practical chitosan production is proposed. Copyright © 2011 Society of Chemical Industry

Heart failure and cardiorenal syndrome: a case report

Cardio-Renal Syndrome (CRS) is a renal dysfunction occurring in a large percentage of pts hospitalised for congestive heart failure (CHF). It is characterised by an excessive fluid retention inside the body, resistance to conventional medical therapy, worsening renal function (WRF) and higher mortality. The prevalence of CRS is likely increased because of the improved survival of HF patients. WRF occurs frequently among hospitalised HFF and is associated with a significantly worse outcome. Clinical features at admission can be used to identify patients at high risk for developing WRF. The clinical case presented concerns a 70-year-old diabetic man with post-ischemic cardiomyopathy and chronic kidney failure, admitted to our division for acute heart failure. During hospitalisation he showed a progressive WRF and resistance to diuretic treatment. After Ultrafiltration treatment there was a progressive clinical improvement. Many treatments have been investigated in order to improve renal function, but none has been demonstrated to improve clinical outcome. Currently Ultrafiltration is reserved to patients with volume overload when traditional medical therapies fail and/or patients become resistant to diuretics.

Ultrafiltration purification of underground water during its various preconditioning

We have carried out a comparative verification of functional characteristics of polysulfone membranes with the rated molecular-mass maximum 50 kamu in ultrafiltration treatment of underground water containing iron with various preconditioning. It has been shown that in studied conditions the treatment process proceeds against the background of reducing the membrane capacity due to the formation of a deposit of iron hydroxide in the pores and on the surface. It has been established that intensity of decreasing the capacity of membranes and the degree of recovering their initial capacity depend on water preconditioning, which acts as a factor determining these processes. Based on the research results we proposed hypotheses of the mechanisms of sedimentation for studied conditions of ultrafiltration treatment of underground water containing iron.

Effect of ultrafiltration and fining adsorbents on the clarification of green tea

Ultrafiltration, silica gel and chitosan treatment methods were investigated to study the clarification effect on the green tea infusion. The results showed that ultrafiltration reduced the protein and polyphenol content, as well as color of the tea infusion. The silica gel and chitosan treatment were effective methods to clarify green tea infusion; they decreased the haze-active protein significantly, without much effect on the polyphenol. The silica gel and chitosan treatment also reduced the proline content by 18.65% and 23.79%, and histidine amino acid by 90.97%, and 90.31%, respectively. After the silica and chitosan treatment, the protein did not decrease significantly compared to the raw (untreated) infusion, while ultrafiltration treatment reduced the protein content significantly from 11.36 to 5.85 mg/100 mL with the 10 kDa membrane. Transmittance of silica gel and chitosan treated infusion was above 95.0% and 99.0%, respectively; and decreased slowly under prolonged storage time. The chitosan and silica treatment decreased the greenness and yellowness of the green tea infusion.

Facile method to manipulate the molecular weight and practical mass production of chitosan by mechanical shearing and concurrent ultrafiltration treatment

AbstractThe objective of this study was to propose a facile method to manipulate the molecular weight and practical mass production of chitosan by mechanical shearing and concurrent ultrafiltration (UF) treatment. The proposed method was based on the degradation rate and rate constant of various process variables, such as: solution temperature, reaction time, concentration of chitosan solution, with or without concurrent removal of degraded fragments during mechanical shearing. The result obtained was that the degradation rate constant was 1.8–6.0 times higher for those using UF to remove smaller degraded molecules concurrently during treatment, than that without UF treatment. The degradation rate constant increased with increasing solution temperature; however, the solution temperature should not exceed than 50°C to prevent the undesired color changes of the resulting product. A method combining mechanical shearing/UF treatment at 50°C and ultrasonic radiation or microfluidization/UF treatment at 30°C is proposed here for a facile method to manipulate the molecular weight of the resultant chitosan with an energy saving, efficient and practical mass production. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Ultrafiltration for the treatment of diuretic-resistant, recurrent, acute decompensated heart failure: experience in a single center

We report our experience with ultrafiltration to remove fluid overload in patients with diuretic-resistant, decompensated, congestive heart failure. From 2005 to 2008, 42 patients with heart failure and left ventricular ejection fraction less than 40% were treated with ultrafiltration. Patients were hospitalized for acute decompensation. Mean age was 69 years (67% men). Cause of heart failure was ischemic in 52% of cases. New York Heart Association (NYHA) class was III (64%) or IV (36%). All patients were on optimal heart failure drugs. Average dose of furosemide before ultrafiltration was 250 mg. Exclusion criteria were contraindications to anticoagulants, hematocrit more than 50%, glomerular filtration rate less than 30 ml/min and cardiogenic shock. Ultrafiltration was performed using a venous femoral bilumen catheter and anticoagulation with heparin. Each patient underwent one to four ultrafiltration treatments (total 70). Mean duration of a treatment was 6 h. Eighty-six percent of treatments removed more than 4000 ml of fluids; 10% removed 2000-4000 ml; 4% removed less than 2000 ml (1600-6900 ml). One ultrafiltration was aborted because of persistent hypotension. Other complications include two cases of bleeding from vascular access and six cases of worsened renal function. One patients required dialysis. Six-month mortality after ultrafiltration was 26%. Hospitalization rate, 6 months after, was 30% (compared to 66% 6 months before). Average furosemide dose, 6 months after, was 125 mg. Ultrafiltration removed fluid overload in diuretic-resistant, severe, congestive heart failure in our single-center experience. Six months after ultrafiltration, hospitalization rates were reduced by 36% and furosemide dose was 50% lower, compared to the previous 6 months. Worsened renal function was the most common complication (14% of patients).

Occurrence of emerging contaminants, priority substances (2008/105/CE) and heavy metals in treated wastewater and groundwater at Depurbaix facility (Barcelona, Spain)

The presence of 170 pharmaceuticals, personal care products, priority substances according to the 2008/105EU Directive and four metals (Cd, Ni, Hg, Pb) have been investigated at the Llobregat delta, south of Barcelona (Spain). In the area, reclaimed water is destined to satisfy environmental uses, irrigation and the construction of a hydraulic barrier against seawater intrusion in the deep aquifer of the delta. A monitoring survey was undertaken of water samples from a tertiary wastewater treatment plant (Depurbaix), treated waste water with an additional treatment of ultrafiltration, reverse osmosis, and UV disinfection (WWATP, for the hydraulic barrier injection). Groundwater samples from the aquifer receiving recharge were also investigated. The pharmaceutical group of substances was detected in sampled waters at concentrations rarely exceeding a few μg/L, among the compounds Caffeine, Nicotine and Galaxolide (musk fragrance) were found to be present in more than 60% of the samples. Diuron was the only priority substance detected. The four metals were always present in a variable concentration. After the WWATP treatment the majority of analytes are removed from tertiary treated wastewater or their concentration is reduced below 0.1 μg/L. Monitoring revealed a widespread occurrence of analysed compounds in groundwater. Among them Codeine (analgesic), Ibuprofen (anti-inflammatory), Iopamidol, Iopromide (contrast agent) and Paraxanthine (metabolite of caffeine) have only been detected in groundwater, and are not present in water currently being injected in the deep aquifer.

Produced Water Treatment by Micellar-Enhanced Ultrafiltration

A water treatment approach combining ultrafiltration (UF) and micellar-enhanced ultrafiltration (MEUF) techniques was used for the removal of organic contaminants in field produced water samples from Canada and the United States. Free oil droplets and suspended solids were separated by initial UF treatments while MEUF was necessary for the removal of dissolved organics. It was shown that the amphiphilic characteristics of some organics commonly existing in produced water contributed to lowering the critical micelle concentration (CMC) of the surfactant employed. Lower surfactant concentrations could, therefore, be employed leading to lower fouling and back contamination and higher permeate flux. In addition, the incorporation of organic contaminants into the structure of cetylpyridinium chloride (CPC) micelles resulted in larger size and higher dissolution capacity of the "mixed micelles". The performance of polymeric and ceramic membranes of different molecular weight cutoffs (MWCOs) was evaluated by analyzing the permeate flux, recovery ratio, and solute percent rejection as functions of trans-membrane pressure (TMP). A mathematical model based on Darcy's law and the resistance in-series model successfully described the flux decline as a function of TMP for the two field samples and the two membranes studied.