Chemical Enhanced Primary Treatment of Wastewater

EJERS, European Journal of Engineering Research and Science Vol. 4, No. 4, April 2019 Chemically Enhanced Primary: Treatment of Wastewater Mona M. A. Abdel-Fatah and Ghada A. Al Bazedi  Abstract—The Chemically enhanced process is considered to be a physicochemical technology for domestic wastewater treatment. The objective of this paper is to improve the efficiency of primary treatment processes and reducing the Hazardous Material and cost of the secondary treatment stage either by eliminating a biological treatment, where conditions and standards allow or by reducing the secondary treatment requirements. Analysis of physicochemical parameters as well as the treatment efficiency of aluminum sulfate (alum), ferric chloride (FeCl3), lime (CaO), and seawater was used. The effect of pH and the coagulant dosages were studied as well as mixing and settling time. Conditions were optimized according to the removal efficiencies measured in terms of reduction in the concentration of total suspended solids (TSS), biological oxygen demand (BOD5), and chemical oxygen demand (COD). The optimum COD removal % was achieved at a settling time of 20 minutes, while at pH~6, alum gave a high turbidity % removal of approximately 90% at the dose of 70 mg/l. FeCl3 gave a high turbidity % removal of approximately 95% at the dose of 40 mg/l. Turbidity removal and TSS removal gave a similar pattern at a settling time of 10-20 minutes, where best results were achieved. The results also showed that at pH~4, FeCl3 gave high COD% removal of approximately 90% at the dose of 40 mg/l. By studying the effect of stirrers’ speed (rpm), the results showed that an increase in the mixing intensity, above 80 rpm decreases the removals of COD, Turbidity and TSS when using alum as a coagulant. Index Terms—Chemical Enhanced Primary Treatment, Wastewater, Coagulants, Removal Efficiencies, Hazardous Material. I. INTRODUCTION CEPT for wastewater is an approach that serves as an attractive opportunity for conventional primary treatment. CEPT adopts coagulation, flocculation and it accomplishes remarkably will increase within the lamination of pollution load from the influent stream [1],[2]. Chemical precipitation is one of the main chemical unit processes used for wastewater treatment; where removal efficiencies depend on mixing times/type (mechanical or hydraulic), and coagulant types/dosage. Al2(SO4)3•18H2O is the most commonly used coagulant for CEPT in wastewater treatment works [3]-[5]. The required coagulant dose for the treatment depends on characteristics of wastewater, this includes; pH value, the phosphate level, and also it requires the determination of the point of injection [6]. The advantages of chemical precipitation of wastewater include the availability of equipment, chemicals, with higher removal efficiency in terms of TSS, BOD5, COD, as well as the size reduction for the following secondary treatment equipment. By using chemical precipitation, it is plausible to remove approximately 80–90% of TSS while in primary settling tanks without the addition of coagulants it is between 50-70% of TSS. While it achieves 50–80% of BOD5 and 80–95% of the phosphorus, compared to primary settling tanks without addition of coagulants it may remove between 25–40% of BOD5 and 5–10% of phosphorus [7],[8]. Also, it removes about 30–70% of COD [5]. The disadvantages may include competing for reactions, various levels of alkalinity, increasing of operator safety issue, as well as multiplied volumes of primary sludge production which require an additional disposal cost. CEPT based treatment allows sedimentation basin to operate at better overflow rates, even as nonetheless retaining a high removal of TSS and BOD5[9]. This offers a favorable advantage as the treatment infrastructure may be smaller thereby translating into a lower land requirement as well as lower capital cost while giving a fair degree treatment efficiency between 60-70% as compared to a traditional secondary treatment plant [10],[11]. Furthermore, CEPT based plant has minimal electricity/energy requirements as there's no need for aeration which otherwise is an intrinsic characteristic of “aerobic process” whereby the biomass growth is facilitated. Hence it is not a biological process, it is a proof against toxicity in the incoming feed wastewater which in any other case has the potential to disrupt operations of activated sludge and USAB technology based plant life. Due to the simplicity of the process, CEPT does no longer involve any rigorous monitoring of operating parameters, e.g., DO (dissolved oxygen), sludge age, return sludge ratio, and so on., and therefore it additionally does not require distinctly professional manpower [12]-[16]. II. MATERIALS AND METHODS For the present investigation, the sample was collected at the discharge from grit removal chamber from the municipal wastewater treatment plant, and of the effluent from the primary settling tank were collected and then transferred to the laboratory. Table (I) below summarizes the wastewater characteristics of effluent from the grit removal chamber. Samples were collected approximately at the same time of the day (9:30 am). Published on April 27, 2019. M. M. A. Abdel-Fatah is with the Chemical Engineering and Pilot Plant Department, Engineering Research Division, National Research Centre, Dokki, Cairo, Egypt. ([email protected]). G.. A. Al Bazedi is with the Chemical Engineering and Pilot Plant Department, Engineering Research Division, National Research Centre, Dokki, Cairo, Egypt. DOI: http://dx.doi.org/10.24018/ejers.2019.4.4.1252 115 EJERS, European Journal of Engineering Research and Science Vol. 4, No. 4, April 2019 TABLE (I) ANALYSIS OF MUNICIPAL WASTEWATER SAMPLE Grab Samples Parameters Average Medium Max COD, mg/l 430 417.5 882 Turbidity, FTU 260 215 418 TSS, mg/l 377 365 825 pH 7 7.46 8.24 Temperature, oC 22 21.2 27 Settable matter, ml/l 14 15 26 TABLE (II) EQUIPMENT USED IN PARAMETRIC MEASUREMENTS Parameter Equipment Min 193 167 237 7.13 17.1 2 Temperature pH Turbidity COD TSS Settable matter The Cole Parmer Economy pH/mV/oC Bench top Meter Hach Reactor Model 45600 and model DR2000 Spectrophotometer Imhoff cones III. RESULTS AND DISCUSSION A. Chemicals used Different chemicals were tested as coagulants and coagulant aids, i.e. metal salts and poly-electrolytes. The used chemicals were of local origin, for the reason of their availability and their reasonable cost. Three coagulants, lime, alum, and FeCl3 were examined. Alum’s working pH range is between 4 and 8 and that of ferric chlorides between 3.5, 6.5 and 8.5 B. Coagulants • Alum, Al2(SO4)3-16H2O with purity 97%, M.W.630.38 (ADWIC, El-Nasr Co.) • Fe Cl3, with purity 99% M.W.162.21 (Riedel-de Haen) • Lime, with purity 90% M.W.74.09 (Sd Fine-Chem Ltd) A. Effect of pH The effect of pH on the efficiency of the process has been evaluated for each coagulant as percentage removal of COD, turbidity, and TSS. The efficiency of the process is affected by the variation of pH. Each coagulant has an optimum pH where maximum efficiency is attained. The results are shown in Figs (1-3). It is readily noted from the results that the pH has a reasonable effect on the efficiency of the process. The optimal values of pH, as observed from the curves in Figs (1-3) are 6, 4, 11.2 for alum, ferric chloride and lime respectively. For lime, no chemical addition was necessary to reach pH 11.2. Coagulant used: Alum 70 mg/l 100 Coagulant aids Magnafloc155, Magnafloc1011, Poly acrylamide, Sea water (above 35,000 ppm TDS) 90 % removal C. • • • • 80 70 60 Turbidity 50 3 4 5 6 pH, after 7 8 TSS Fig (1) Effect of pH on removal using Alum as a coagulant Coagulant used: Ferric chloride, 20 mg/l 100 90 % removal D. Experimental set-up of Jar Test Wastewater coagulation, flocculation, and sedimentation were performed via a standard jar test apparatus (Phipps and Bird 400 series six-paddle stirrer) were used in all experiments. Paddles and shafts were made of stainless steel. The stirrers feature regulated variable speeds, 0-300 rpm, with a digital readout. The coagulant doses were added to wastewater samples and then two types of mixing were investigated. COD 2 80 70 The chemical precipitation procedure consisted of rapid mixing to 100 rpm and the slow mixing of 30-50 rpm in different settling time. The following parameters were investigated: 60 Turbidity 50 2 3 4 5 6 pH, after 7 8 COD TSS Fig (2) Effect of pH on removal using FeCl3 as a coagulant The effect of pH, The effect of the coagulant type and dosage, The effect of slow-mixing intensity, The effect of the time-length of a slow mix, The effect of the settling time, The effect of a coagulant aid, and The effect of adding sea water. E. Measurements All the analytical measurements have been conducted, using the equipment as written in Table (II). The COD, turbidity, and TSS are the key parameters for determining the process efficiency. DOI: http://dx.doi.org/10.24018/ejers.2019.4.4.1252 Coagulant used: Lime: 600 mg/l 100 90 % removal • • • • • • • 80 70 60 Turbidity 50 COD 40 0 5 pH, after 10 15 TSS Fig (3) Effect of pH on removal using Lime as a coagulant 116 EJERS, European Journal of Engineering Research and Science Vol. 4, No. 4, April 2019 Coagulant used: Alum w/o pH adjustment Initial conditions: COD = 394 mg/l turbidity = 261 FTU TSS = 332 mg/l 80 70 60 Turbidity COD 50 0 10 20 30 40 Alum dose, mg/l 50 60 TSS Fig (4) Effect of low alum dose on % removal This pH value was reached as a result of lime addition itself. Nearly similar trends were noted in removals of COD, turbidity, and TSS. Since regulations requirements with reference to pH determine the range determined is from 6–9, another set of experiments were carried out without pH adjustment Figs (4-5). Even though slightly lower removals are obtained, pH is in the recommended levels. Coagulant used: Alum w/o pH adjustment 100 Initial conditions: COD = 394 mg/l turbidity = 261 FTU TSS = 332 mg/l 80 70 Coagulant used: Alum at optimum pH (~6) Turbidity 60 COD 50 TSS 60 70 80 90 100 Alum dose, mg/l 110 120 Fig (5) Effect of medium alum dose on % removal B. Effect of coagulant types and dosage The effects of alum dosages on the percentage removal of COD, turbidity, TSS are illustrated in Figs (6-7). The effects of FeCl3 dosages on the % removal are shown in Figs (8-9). The effects of lime dosages are given in Figs (10–11). As presented in Figs (6-11), FeCl3 gave a higher COD % removal. At pH~6, use of alum gave a high COD % removal of approximately 75% at the dose of 70 mg/l. Increasing the coagulant dose increased the efficiency very gradually until it reached a removal of 80% at a dose of 120 mg/l. After that, the removal % didn’t change. When observing the removal % when using FeCl3, there is a similar pattern as for when using alum. At pH~6, use of alum gave a high removal of the turbidity percentage, of approximately 90% at the dose of 70 mg/l Figs (6-7). An increase in the coagulant dose increased the efficiency slightly to the removal of 90-95%. After that, removal percentages stayed stable. FeCl3 gave a high removal of the turbidity percentage, of approximately 95% at the dose of 40 mg/l in Figs (8-9). DOI: http://dx.doi.org/10.24018/ejers.2019.4.4.1252 100 90 80 70 60 50 40 30 20 10 0 Initial conditions: COD = 193 mg/l turbidity = 182 FTU TSS = 330 mg/l % removal % removal 90 Stability of the percentage of turbidity removal remained until the dose increased to 80 mg/l after that decrease began. Lime addition gave high removals of the turbidity percentage. At a dose of 600 mg/l, the removal percentage reached above 90% Figs(10-11). Using FeCl3 as a coagulant (at pH~4), its dose of 40 mg/l gave a removal percentage of almost 100% which remained almost stable till the dose of 90 mg/l. After that a decrease in TSS removal took place. TSS removal reached approximately 97% when using lime as a coagulant. TSS removal remained stable as the lime dose increased. Turbidity COD 0 20 40 60 80 Alum dose, m g/l 100 120 TSS Fig (6) Effect of low/medium alum dose on % removal Coagulant used: Alum at optimum pH (~6) 100 Initial conditions: COD = 346 mg/l turbidity = 313 FTU TSS = 366 mg/l 90 % removal % removal 90 At pH~4, use of FeCl3 gave high COD% removal of approximately 90% at the dose of 40 mg/l Figs (8-9). At a dose of 60 mg/l, COD % removal reached slightly above 90%. An increase of the dose above this level caused instability in the % removal.No chemical addition was necessary when using lime since the optimum pH was reached as a result of the lime addition. A good removal percentage was reached starting at a dose of 600 mg/l (~60% COD removal). Use of the three coagulants: alum, ferric chloride gave similar results for turbidity removal. The pattern of the removal of TSS is similar to that of turbidity removal. The three coagulants gave very good results for TSS removal. The TSS removal reached ~96% using alum (at pH~6) and reached almost 100% removals after increasing the dose Figs (6-7). After that, removal percentages stayed stable. 80 70 Turbidity 60 COD 50 120 TSS 130 140 150 160 Alum dose, mg/l 170 180 Fig (7) Effect of high alum dose on % removal 117 EJERS, European Journal of Engineering Research and Science Vol. 4, No. 4, April 2019 Coagulant used: FeCl3 at optimum pH (~4) 100 % removal 90 80 70 Turbidity 60 COD 50 0 10 20 30 40 50 Ferric chloride dose, mg/l 60 TSS C. Effect of Slow-Mixing Intensity The optimum slow-mixing intensity varies in the range between 30-50 rpm for the three coagulants. Two sets of experiments were carried out. In the case of using alum, Fig (12) shows that 50 rpm gives the highest removal percentage of COD, turbidity, and TSS, while Fig (13) shows that good results are obtained at 30 rpm. The case is similar when using FeCl3 and lime as seen in Figs (14-15). Studying the effect of stirrers speed (rpm); reveals that increasing the mixing intensity, starting at 80 rpm decreases the removals of COD, Turbidity and TSS when using alum as a coagulant. Fig (8) Effect of low ferric chloride dose on % removal Coagulant used: Alum, 80 mg/l, pH~6 Coagulant used: FeCl3 at optimum pH (~4) 100 100 % remova 90 % removal 90 80 70 80 70 Turbidity 60 60 Turbidity COD 50 0 COD 50 60 70 80 90 100 110 Ferric chloride dose, mg/l 120 20 TSS 40 60 Slow mix, rpm 80 TSS Fig (12) Effect of intensity of slow mix on % removal using alum (80 mg/l) ig (9) Effect of medium ferric chloride dose on % removal Coagulant used: FeCl3, 40 mg/l, pH~4 Coagulant used: Lime at initial pH 100 100 % removal % removal 90 80 80 60 Turbidity 40 COD 20 TSS 0 200 70 60 Turbidity COD 50 0 300 400 500 Lime dose, mg/l 600 20 40 60 Slow mix, rpm 80 TSS Fig (13) Effect of intensity of slow mix on % removal using FeCl3 (20 mg/l) Fig (10) Effect of low lime dose on % removal Coagulant used: Lime at initial pH 100 % removal 80 60 40 Turbidity 20 COD TSS 0 0 250 500 750 1000 Lime dose, mg/l 1250 Fig (11) Effect of medium lime dose on % DOI: http://dx.doi.org/10.24018/ejers.2019.4.4.1252 Fig (14) Effect of intensity of slow mix on % removal using FeCl3 (40 mg/l) 118 EJERS, European Journal of Engineering Research and Science Vol. 4, No. 4, April 2019 Coagulant used: Alum Coagulant used: Alum 90 90 % removal 100 % removal 100 80 70 60 COD 0 10 20 30 slow mix, min. 40 70 60 Turbidity 50 80 COD 50 TSS 0 10 20 30 Settling time, min. 40 Coagulant used: Ferric chloride 100 % removal 90 80 70 60 Coagulant used: Lime Turbidity COD 50 100 0 90 % removal TSS Fig (18) Effect of settling time on % removal using Alum Fig (15) Effect of time of slow mix on % removal using Alum D. Effect of the Time of a Slow Mix Figs (16-18) show the results of using alum, FeCl3, and lime as coagulants at their optimum operating conditions. It is clear that COD, turbidity and TSS removals have sufficient removal percentages, starting with 10 minutes of slow mix and they stay more or less constant when the time of slow mix was increased. Turbidity 10 20 30 Settling time, min. 40 TSS Fig (19) Effect of settling time on % removal using FECl3 80 70 Turbidity 60 COD 50 0 10 20 30 Slow m ix, m in. 40 TSS When using ferric chloride, the optimum settling time ranges between 10-20 minutes. The highest COD, turbidity, TSS removals were reached at that settling time Fig (19). Fig (20) also shows that the highest COD, turbidity, TSS removals are obtained at a settling time of 10 minutes when using lime. Fig (16) Effect of time of slow mix on % removal using FeCl3 Coagulant used: Lime 100 Coagulant used: Ferric chloride 100 90 % removal % removal 90 80 70 Turbidity 60 COD 50 TSS 0 10 20 30 Slow mix, min. 40 80 70 60 Turbidity COD 50 0 10 20 30 Settling time, min. 40 TSS Fig (20) Effect of settling time on % removal using Lime Fig (17) Effect of time of slow mix on % removal using Lime E. Effect of Settling Time Fig (18) shows the effect of settling time on COD, turbidity and TSS removals when using alum as a coagulant. The optimum COD removal percentage is achieved at a settling time of 20 minutes. The COD removal is nearly constant with changes in settling time. Turbidity removal and TSS removal have a similar pattern, giving good results at a settling time of 10-20 minutes. DOI: http://dx.doi.org/10.24018/ejers.2019.4.4.1252 F. Effect of Coagulant Aids Magna-floc 155, Magna-floc 1011 and polyacrylamide have been used as coagulant aids. The removals with the use of alum, FeCl3, and lime are given in Figs (21-25). It is clear from all Figs that the use of aid does not improve the removals in any of the operating conditions recorded. 119 EJERS, European Journal of Engineering Research and Science Vol. 4, No. 4, April 2019 Alum + Magna floc 155 Ferric chloride + Magna floc 1011 100 100 90 % removal % removal 90 80 70 60 50 0 0.2 0.4 Coagulant aid dose, mg/l 0.6 80 70 Turbidity 60 COD 50 TSS Turbidity COD 0 0.1 0.2 0.3 0.4 0.5 Coagulant aid dose, mg/l 0.6 TSS Fig (21) Effect of Alum and Magna Floc 155 addition on % removal Fig (25) Effect of FeCl3 and Magna Floc 1011 addition on % removal Alum + Magna floc 1011 G. Coagulant Mixtures Mixtures of coagulants were tested in different proportions in order to obtain better results with reference to chemicals cost and to try to modify the pH of wastewater, as shown in Figs (26- 32). Mixtures with lime, in general, do not give better removals than using lime alone, because even if the lime dosage is small, the effect on increasing the pH is very great. At these high levels of pH, both alum and FeCl 3 do not act effectively, as has been discussed previously. 100 % removal 90 80 70 Turbidity 60 COD 50 0 0.1 0.2 0.3 0.4 0.5 Coagulant aid dose, mg/l 0.6 TSS Coagulants: Alum(70mg/l) + Ferric chloride Fig (22) Effect of Alum and Magna Floc 1011 addition on % removal 100 90 % removal Alum(70mg/l) + Polyacrilamide 100 70 Turbidity 80 60 COD 70 50 90 % removal 80 TSS 0 60 20 40 60 80 100 120 140 160 180 Ferric chloride dose, mg/l Turbidity 50 Fig (26) Use of Alum (70 mg/l) and FeCl3 COD 0 0.1 0.2 0.3 0.4 0.5 Polyacrilamide dose, mg/l 0.6 TSS Alum (50 mg/l) + ferric chloride Fig (23) Effect of Alum and Poly-acrimalyde addition on % removal 100 90 % removal Ferric chloride + Magna floc 155 100 % removal 90 80 80 70 60 70 Turbidity COD 50 60 Turbidity COD 50 0 0.1 0.2 0.3 0.4 0.5 Coagulant aid dose, mg/l 0.6 TSS 0 10 20 30 40 50 Ferric chloride dose, mg/l 60 TSS Fig (27) Use of Alum (50 mg/l) and FeCl3 Fig (24) Effect of FeCl3 and Magna Floc 155 addition on % removal DOI: http://dx.doi.org/10.24018/ejers.2019.4.4.1252 120 EJERS, European Journal of Engineering Research and Science Vol. 4, No. 4, April 2019 Lime (300 mg/l) + ferric chloride Coagulants: Alum (70 mg/l) + Lime 90 90 80 70 Turbidity 60 COD % removal 100 % removal 100 80 70 60 Turbidity TSS 50 50 0 200 400 600 800 lime dose, mg/l 1000 1200 COD 0 FeCl3 (30 mg/l)+ lime 100 % removal 90 80 70 60 Turbidity COD 0 200 400 600 800 1000 1200 TSS lime dose, mg/l Fig (29) Use of FeCl3 (30 mg/l) & lime FeCl3 (30- mg/l)+ alum Lime conc.: 0 mg/l 80 % removal % removal 90 70 Turbidity COD 50 0 50 100 150 alum dose, mg/l 200 TSS H. Effect of Adding Sea water Seawater was used as an inexpensive source of magnesium and lime, to test if it would be effective as well as economically viable in the treatment of wastewater. The results are shown in Figs (33-37). It is clear from Fig (38) that sea water alone has no significant effect on removals. Fig (36) depicts the effect of the addition of seawater to lime on removals. It is clear that the addition of seawater improves the removals at a concentration of 2% (volume percent). Fig (39) gives an indication that the addition of seawater to lime at any dosage, improves the removals, while the best dose is 500 mg/l lime + 4 % sea water. With alum, results were observed and combinations of 60 mg/l alum + 2 % sea water give the minremovals. 100 60 200 Fig (32) Use of Lime (300 mg/l) and FeCl3 Fig (28) Use of Alum (70 mg/l) and Lime 50 50 100 150 Ferric chloride dose, m g/l TSS 100 90 80 70 60 50 40 30 20 10 0 Turbidity COD TSS 0 5 10 Seaw ater conc., % Fig (30) Use of FeCl3 (30 mg/l) and Alum Fig (33) Effect of seawater addition on % removal Lime (300 mg/l) + alum Lime conc.:100 mg/l 100 % removal % removal 90 80 70 60 Turbidity 50 COD 20 40 60 80 100 120 140 160 alum dose, mg/l Fig (31) Use of lime (300 mg/l) and Alum DOI: http://dx.doi.org/10.24018/ejers.2019.4.4.1252 TSS 100 90 80 70 60 50 40 30 20 10 0 COD Turbidity TSS 0 2 4 6 8 Seaw ater conc., % 10 Fig (34) Effect of Lime and variable seawater addition on % removal 121 EJERS, European Journal of Engineering Research and Science Vol. 4, No. 4, April 2019 Seawater conc.: 4% 100 % removal 80 60 40 Turbidity 20 COD 0 TSS 0 100 200 300 400 Lime Conc., mg/l 500 Fig (39) Effect of seawater with Alum addition on % removals IV. CONCLUSION Fig (35) Effect of variable Lime and seawater addition on % removal Alum conc.:60 mg/l % removal 100 90 80 70 60 50 40 30 20 10 0 COD Turbidity TSS 0 2 4 6 8 Seaw ater conc., % 10 Fig (36) Effect of alum and variable seawater addition on % removal % removal Seawater conc. = 2% 100 90 80 70 60 50 40 30 20 10 0 The present study provides an approach for CEPT of wastewater. The obtained results showed that the natural pH-conditions which prevailed with the different coagulants were the most suitable ones. At pH~6, the use of alum gave a high removal of the turbidity of approximately 90% removal at the dose of 70 mg/l while FeCl3 gave a high turbidity %, removal of approximately 95% at the dose of 40 mg/l. Turbidity removal and TSS removal have a similar pattern, best results achieved at settling time of 10-20 minutes. The results also showed that at pH~4, FeCl3 gave high COD% removal of approximately 90% at the dose of 40 mg/l. Also, the effect of stirrers’ speed (rpm) has been investigated, the results reveal that by increasing the mixing intensity, starting from 80 rpm decreases in the removals of COD, Turbidity and TSS, has occurred when using alum as a coagulant. Also, by increasing the coagulant doses above this level, instability in the % removal has occurred. REFERENCES [1] Turbidity [2] COD TSS 0 20 40 60 Alum conc., mg/l 80 Fig (37) Effect of variable alum and seawater addition on % removal [3] [4] [5] [6] [7] [8] Fig (38) Effect of seawater with Lime addition on % removals DOI: http://dx.doi.org/10.24018/ejers.2019.4.4.1252 Ji, J., Qiu, J., Wai, N., Wong, F., & Li, Y. (2010). Influence of organic and inorganic flocculants on physical–chemical properties of biomass and membrane-fouling rate. Water Research, 44(5), 16271635. doi: 10.1016/j.watres.2009.11.013 Wang, C., Dai, J., Shang, C., & Chen, G. (2013). Removal of aqueous fullerene nC60 from wastewater by alum-enhanced primary treatment. 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Water Research, 87, 494-502. doi:10.1016/j.watres.2015.09.027 Mbamba, C. K., Lindblom, E., Flores-Alsina, X., Tait, S., Anderson, S., Saagi, R., Jeppsson, U. (2019). Plant-wide model-based analysis of iron dosage strategies for chemical phosphorus removal in wastewater treatment systems. Water Research. doi:10.1016/j.watres.2019.01.048 Mona A Abdel-Fatah, Marwa M Elsayed, Gh A Al Bazedi, S I Hawash (2016). Sewage Water Treatment Plant Using Diffused Air System. Journal of Engineering and Applied Sciences, Vol. 11(17): pp 10501-10506. DOI: http://dx.doi.org/10.24018/ejers.2019.4.4.1252 Mona A. Abdel-Fatah, I am Assistant Professor in Department of Chemical Engineering & Pilot Plant, Engineering Division, National Research Centre, Egypt. My work is concerned with the development of new techniques for treatment of water and wastewater from hazardous compounds and reused & recycled treated water. I have an excellent experience in this field more than 25 years; I am a Consultant Engineer in the field of Management of Industrial & Domestic Wastewater - Consultant No. 241/5/2010. 2012 PhD in Chemical Engineering, Faculty of Engineering, Cairo University, “Study of Dye-house Wastewater Treatment Using Nanofiltration Membranes”. 2004M.SC in Chemical Engineering, Faculty of Engineering, Cairo University, “Assessment of Alternative Solutions of Industrial Wastewater Management in the Textile Industry”.1998Diploma in Chemical Engineering, Cairo University, “Industrial Wastewater Treatment Project for Textile Industries”. Ghada A. Al Bazedi, was born in Cairo, Egypt, in 1975. She received the B.E. degree in chemical engineering from Cairo University, Egypt, in 1998, and the MSc. and Ph.D. degrees in chemical engineering from Cairo University, Egypt, in 19 and 2012, respectively. In 2006, she joined the Department of Chemical Engineering and Pilot Plant, National Research Center- Egypt, as an Assistant Researcher, and in 2012 became a Researcher “Assistant Professor”. Since 2012, she has been with the Department of Chemical Engineering, as an Assistant Professor. Her current research interests include adsorption technologies, water treatment, and hydrogel development for different applications as well as engineering economics. Dr. Al Bazedi is a Fellow of the Egyptian Engineering Syndicate; IAENG. She alo act as a reviewer for diferent journals e.g. Desalination and Water Treatment, Environmental Engineering Science, as well as tce “Institution of Chemical Engineers (IChemE)”. She was one of the judges at the ideagym-egypt 2016. 123