Pilot scale investigation of coagulation combined with ozonation and pH adjustment in treatment of NOM rich water

2016 ◽  
Vol 16 (3) ◽  
pp. 837-844 ◽  
Author(s):  
A. Tubić ◽  
J. Agbaba ◽  
J. Molnar Jazić ◽  
M. Watson ◽  
B. Dalmacija

This paper presents the results of a pilot scale investigation of coagulation using aluminium based coagulants (polyaluminium chloride sulphate (PACL1) and polyaluminium chloride (PACL2)), combined with pre-ozonation and pH adjustment, on natural organic matter (NOM) removal from groundwater. Tests were conducted at a semi-industrial pilot plant, using groundwater with a high content of NOM (5.1 ± 0.8 mg C/L dissolved organic carbon (DOC); 0.211 ± 0.007 cm−1 UV absorbance at 254 nm (UV254)) and trihalomethane formation potential (THMFP (273 ± 73 μg/L)). It was determined that both coagulants showed similar efficacy in reducing DOC (∼50%), UV254 (∼60%) and THMFP (∼65%). Application of pre-ozonation enhanced total coagulation efficiency (up to 61% and 80% for DOC and UV254, respectively), probably due to its microflocculation effect. THMFP in the treated water fluctuated depending on ozone dose, coagulant type and pH. The pre-treatment resulted in NOM oxidation to lower molecular weight hydrophilic organic substances. PACL1 coagulation did not efficiently remove these new THM precursors, whereas PACL2 was able to reduce THMFP to 77 μg/L at a low ozone dose of 0.4 mg O3/mg DOC, suggesting differences in the coagulation mechanism for the two coagulants. This difference confirms the necessity of optimizing the combined treatment depending upon the choice of coagulant applied.

2004 ◽  
Vol 49 (4) ◽  
pp. 63-68 ◽  
Author(s):  
J. Agbaba ◽  
I. Ivančev-Tumbas ◽  
B. Dalmacija ◽  
M. Klašnja

Formation of aldehydes and trihalomethanes during intermediate ozonation of water pretreated with ozone and polyaluminium-chloride was monitored in a pilot-scale study to optimize the drinking water treatment technology. The raw water was the groundwater, rich in natural organic matter, originated from the territory of the Northern Banat region in Vojvodina Province, Serbia and Montenegro. Monitoring of the parameters that have to meet prescribed criteria (permanganate value, TOC and THMFP removal) could not give an indication on how to split the required ozone dose between preozonation and intermediate ozonation. As the effects obtained regarding THMFP and TOC removal were similar, monitoring of aldehydes was performed, and this clearly showed that preozonation should be carried out with a dose ≥0.4 mg O3/mg TOC to obtain the water with the smallest contents of aldehydes and the lowest specific content of glyoxal in the GAC filter influent.


2002 ◽  
Vol 45 (12) ◽  
pp. 347-354 ◽  
Author(s):  
G. Andreottola ◽  
P. Foladori ◽  
M. Ragazzi ◽  
R. Villa

Pilot-scale experiments were carried out applying the SBBR process (Sequencing Batch Biofilm Reactor) for the treatment of winery wastewater. The aim was the evaluation of the SBBR performance and the development of a control strategy based on dissolved oxygen (DO) for the optimisation of the SBBR treatment cycle and the minimisation of the energy supply. The results of the experimentation have confirmed the applicability of the SBBR process pointing out high COD removal efficiencies between 86% and 99%, with applied loads up to 29 gCOD m−2 d−1, corresponding to 8.8 kgCOD m−3 d−1. The on-line monitoring of DO concentration appeared as a good indicator of the progress in the COD biodegradation. The control strategy for the ending of the SBBR cycles was based on the time derivative of the DO concentration. The optimised control strategy makes it possible to obtain a steady quality of the effluent wastewater with an average daily applied load of 6.3 kgCOD m−3 d−1 rather than 3.5 kgCOD m−3 d−1 for the non-optimised SBBR cycle. The possibility of optimising the SBBR cycle through a simple control of the DO in the mixed liquor could be an interesting solution for the biological pre-treatment of winery wastewater to be discharged into sewerage or as a single-stage of a combined treatment plant for the discharge into surface water.


2010 ◽  
Vol 10 (4) ◽  
pp. 591-599
Author(s):  
N. Vigneron-Larosa ◽  
A.-S. Lescourret ◽  
A. Bignon ◽  
C. Breda ◽  
B. Bozkaya-Schrotter ◽  
...  

In surface water nanofiltration (NF) for drinking water production, 15 to 25% of the feed is rejected by the membranes. Two complementary approaches are investigated in order to manage concentrates. On one hand, an additional NF stage allows an increase in the yield of drinking water production from 85 to 94%. Thirty-days filtration cycles are achieved. Conductivity, natural organic matter (NOM) and micropollutant contents of permeate fully satisfy drinking water standards. On the other hand removal of phosphonates, micropollutants and NOM is investigated in order to treat the concentrate before disposal. Phosphorus is removed by adsorption on pre-treatment sludge: removal reaches 82% with 100 ppm of suspended solids. To eliminate pesticides and NOM, adsorption on granular activated carbon (GAC) is studied with pilot scale fixed bed columns. Within 20 minutes contact time, selected pesticides are completely eliminated. NOM removal is approximately 30% with wood based GAC.


2003 ◽  
Vol 3 (5-6) ◽  
pp. 125-132 ◽  
Author(s):  
G. Galjaard ◽  
J.C. Kruithof ◽  
H. Scheerman ◽  
J. Verdouw ◽  
J.C. Schippers

Ultrafiltration of surface water without pre-treatment frequently suffers from high fouling rates and irreversible fouling. Enhanced pre-coat engineering (EPCE) has been developed with the aim to enable ultrafiltration plants to treat surface water directly at high and stable flux rates. In this study in-line coagulation with ferric chloride and polyaluminium chloride and EPCE are compared on pilot scale using capillary membranes with IJssel Lake water as feed water. The in-line coagulation experiments resulted in relatively low flux rates and irreversible fouling, whereas EPCE enabled us to achieve a flux rate of 100 l/(h.m2) and a dosage of less than 25 g/m3. However, a couple of technical questions need to be answered before fullscale application can be implemented with all types of ultrafiltration systems.


2015 ◽  
Vol 16 (2) ◽  
pp. 305-313 ◽  
Author(s):  
Euis Nurul Hidayah ◽  
Yung-Chen Chou ◽  
Hsuan-Hsien Yeh

In this study high performance size exclusion chromatography (HPSEC) was used to compare an ultrafiltration (UF) membrane and alum coagulation for their capacity to remove different fractions of natural organic matter (NOM) from water. At the same time, the removal of disinfection by-product (DBP) precursors, as measured by trihalomethane formation potential (THMFP) and haloacetic acid formation potential (HAAFP), was also detected. The results show that the UF membrane mainly removed the aliphatic biopolymer fraction, while alum coagulation mainly removed the humic substances fraction. The results of DBP precursor analysis show that more THMFP was removed by the UF membrane than HAAFP, while the reverse was true for alum coagulation. It is conjectured that the aliphatic biopolymer fraction is the major precursor for trihalomethanes (THMs), while the humic substances fraction is the major precursor for haloacetic acids (HAAs).


2006 ◽  
Vol 54 (5) ◽  
pp. 33-41 ◽  
Author(s):  
D. Dursun ◽  
M. Turkmen ◽  
M. Abu-Orf ◽  
S.K. Dentel

The effect of enzyme pre-treatment on dewaterability of anaerobically digested sludge was investigated at both laboratory and pilot scale. Our results revealed a significant increase in cake solid content (27% cake solids compared to 18% without enzyme pre-treatment), using an enzyme dose of only 20 mg/L. In order to assess practical application, enzyme pre-treatment was applied at the Wilmington, Delaware (US) wastewater treatment plant, using a pilot-scale centrifuge. However, the efficiency reached in laboratory scale could not be obtained in pilot scale, where the final cake solids content did not exceed 20%. Centrifuge and belt filter press (simulated by Crown Press™) dewatering were compared in terms of the process efficiencies in the absence and presence of enzyme pre-treatment. Possible factors that might cause the differences were tested by experimental and statistical comparisons. Results indicated that the higher shear applied in centrifugation is responsible for the lack of improved cake solids. The network strength of sludge determined by rheological measurements revealed that enzymatic treatment weakens the gel structure of the sludge floc through the hydrolysis of extracellular polymeric substances; this allows improved dewatering by filtration processes, but leads to floc deterioration when subjected to high shear during centrifugation.


2004 ◽  
Vol 4 (4) ◽  
pp. 89-94 ◽  
Author(s):  
R. Fabris ◽  
C.W.K. Chow ◽  
M. Drikas

Three different powdered activated carbons were applied in combination with aluminium sulphate to treat a high dissolved organic carbon (DOC) source water with a focus on improving natural organic matter removal. Treated water quality was analysed using absorbance at 254 nm, DOC, trihalomethane formation potential (THM-FP), rapid fractionation, C13 NMR and molecular weight distribution by high performance size exclusion chromatography. Carbon C and B offered equivalent DOC removal but carbon C was considered superior as treated water THM-FP was reduced. It is postulated that an organic fraction around 1000 Daltons is responsible for differences in THM-FP shown in the treated waters.


1992 ◽  
Vol 25 (2) ◽  
pp. 291-298 ◽  
Author(s):  
B. Koch ◽  
J. T. Gramith ◽  
M. S. Dale ◽  
D. W. Ferguson

A pilot-scale study of ozone and PEROXONE (ozone in combination with hydrogen peroxide) for the removal of the odorous compounds 2-methylisoborneol (MIB) and geosmin in drinking water has been conducted at the Metropolitan Water District of Southern California. The study investigated the effects of ozone dosage, ratio of hydrogen peroxide to ozone (H202/03), and contact time. It was found that MIB and geosmin removal increased with higher applied ozone doses, but longer contact times over the range of 6-12 min were not significant. It was determined that 80-90 percent removal could be achieved with an ozone dose of approximately 4.0 mg/l, as compared to an ozone dose of approximately 2.0 mg/l at a H202/03 ratio of 0.2. Also investigated were the effects of alternative contactor configurations, ferrous sulfate as an alternative coagulant, bromide and ammonia addition, and simulated turbidity on the removal efficiencies of the two odorous compounds.


2014 ◽  
Vol 15 (1) ◽  
pp. 34-41 ◽  
Author(s):  
J. Molnar ◽  
J. Agbaba ◽  
A. Tubić ◽  
M. Watson ◽  
M. Kragulj ◽  
...  

This work investigates the effects of ultraviolet (UV)/H2O2 advanced oxidation on the content and characteristics of natural organic matter (NOM) originating from two different groundwaters (3.03–9.69 mg/L total organic carbon (TOC), 2.71–4.31 Lmg−1m−1 specific ultraviolet absorbance (SUVA)). Application of UV irradiation resulted in a minor reduction in the total content of NOM. Using UV/H2O2 advanced oxidation led to a significant reduction of the aromatic character of NOM (SUVA was reduced by up to 80%) and an increase in the hydrophilic character of the residual NOM, with the optimal UV/H2O2 treatment conditions depending on the water type. In addition, fluctuations in trihalomethane formation potential (THMFP) were observed depending on the UV/H2O2 process conditions, with a maximal reduction of about 40% achieved for both waters.


2018 ◽  
Vol 2 (2) ◽  
Author(s):  
Jose Baeza Noci

INTRODUCTION: The use of ozone, intra or periarticular, for knee and hip joint osteoarthritis (KO / HO) is clearly justified by its anti-inflammatory and antioxidants properties, that should diminish the arthritic episodes of this disease [1]. Several papers have proved the safety and efficacy of this treatment for KO [2-12], comparable to other classical treatments (steroids or hyaluronic acid (HA)) [13-14]. However, there is no paper about HO yet. STUDY DESIGN: This work is based on two open prospective studies started in February 2002 and stopped in February 2010, one group for each joint. Recruitment criteria for both groups were: - Kellgren& Lawrence KO classification: any - One/bilateral - No previous joint trauma - No rheumatic disorder - No previous surgery (but arthroscopic meniscectomy) - NSAIDs for at least two months - Promise to abandon any anti-inflammatory drugs during ozone treatment - Informed consent Clinical evaluation for KO was done using WOMAC questionnaire, pre-treatment and 1, 3, 6, 12 months after treatment. In case of HO, we used VAS for evaluation instead. CLINICAL DATA: All patients have, at least, 12 months follow-up. For KO, we have complied 199 patients (225 knees). There are two missing cases, not compiled, due to death at the 1 year revision. Age of sample ranged from 51 to 89 during the treatment. WOMAC pre-treatment was: -Pain 13.3 -Stiffness 5.6 -Function 46.2 Other data compiled, were: age, gender, BMI, Kellgren & Lawrence radiological scale (I to IV) and relapses (time free of symptoms). For HO, we have compiled 126 patients (133 hips). There are no missing cases at one year follow-up. Age ranged from 49 to 83. EVA pre-treatment was 7,33. Other data compiled, were: age, gender, BMI, use of imaging, Kellgren & Lawrence radiological scale (I to IV) and relapses (time free of symptoms). OZONE TECHNIQUE: All patients got one intarticular injection of ozone, once a week; in case of associated tendinitis or bursitis, a second or third injection was done together the intrarticular one. Injections were performed under strict asepsy. For the knee, we used a 27G x 30 mm needle with a syliconized syringe and a supero-lateral approach and. Ozone dose for intraticular injection was 15 mL at 20 mcg/mL.[15-16] Paratendon injection was performed with 5 mL at 20 mcg/mL. We always did a minimun of three intrarticular injections. Patients that did not improve were classified as failure. For the rest of the patients, the average number of injections was 4,8 (range 3 to 7). For the hip, we used a 25G x 90 mm needle with a syliconized syringe and a lateral approach. Ozone dose for intraticular injection was 5-10 mL at 20 mcg/mL.[15-16] Paratendon injection was performed with 5 mL at 20 mcg/mL. 45 patients were injected with imaging guide due to severe obesity. In these patients we used a 22G x 205 mm needle. We always did a minimun of three intrarticular injections. Patients that did not improve were classified as failure. For the rest of the patients, the average number of injections was 5 (range 3 to 10). RESULTS: From 225 knees, 44 (19.5% - the “bad result” group) did almost not improve at all; other rescue treatments were offered. The rest (80.5%) achieved a significant improvement, increasing WOMAC index over 25% of their basal level. The clinical improvement was obtained during the treatment or the first three months after treatment. WOMAC global improvement was 48%, including both groups. Relapses over the “good result” group have been of 8% at 1 year revision, and are statistically related just with Kellgren & Lawrence classification. We registered no side effect that needed further treatment. From 133 hips, 80% improved at least 2 points in VAS and 73% improved at least 3 points. The one month follow-up VAS score was 3,3 (improvement of 55%). From the patients that improved, 25% had a relapse at 1 year visit, and are statistically related just with Kellgren & Lawrence classification. The use of imaging support did not improved the results. We registered no side effect that needed further treatment. DISCUSSION: Results for KO are similar to Moretti's paper [12] and similar to the ones published for HA papers [15]. These last papers are almost always referred to 6 month follow-up. Comparing our results with HA papers at one year follow-up, they are clearly better. Longer term results for HA are even worse. This study has flaws due to its design, but similar design has been used for reporting results about drugs, HA or surgery, so comparison can be done. For HO, the results are even better that the one published for steroids or HA injections [17-18]. We agree with the publication about the use of imaging [19]. CONCLUSION: Ozone treatment in KO improves clinical outcomes over 25% of its base level in more than 80% of the patients. Relapse rate is 8% and is related with advanced osteoarthritis (Kellgren & LAwrence grades III-IV); minimal time free of symptoms is almost one year. The similarity with Moretti's results in a double blind clinical trial strength the indication for ozone in patients with KO. No paper has been published yet about HA, but comparing the results with steroids or HA injections, this treatment option is promising.


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