A Study of the Suction Height Effect on Turbidity Removal Efficiency of Water in Pulsator

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Global Journal of researches in engineering General engineering Volue 2 Issue 2 Version.0 May 202 Type: Double Blind eer Reviewed International Research Journal ublisher: Global Journals Inc.

Shekarabi Islaic Azad University, Science & Research branch, Tehran, Iran Abstract - In water treatent plants in ost countries around the world to achieve the desired standard of water quality, soe

Aong these units, the process of sedientation is of prie iportance, because nearly 70% of water turbidity is reoved in this unit.

This paper is aied at studying the suction height effect on turbidity reoval efficiency of water in ulsator. This ethod is investigated experientally by using a pilot scale odel.

1 Global Journal of researches in engineering General engineering Volue 2 Issue 2 Version.0 May 202 Type: Double Blind eer Reviewed International Research Journal ublisher: Global Journals Inc. (USA) Online ISSN: & rint ISSN: A Study of the Suction Height Effect on Turbidity Reoval Efficiency of Water in ulsator By Seyed Mostafa Khezri, Elahe Dadvar & Heliasadat Hosseini Shekarabi Islaic Azad University, Science & Research branch, Tehran, Iran Abstract - In water treatent plants in ost countries around the world to achieve the desired standard of water quality, soe units such as grid chaber, coagulation, sedientation, clarification, filtration and disinfection are required. Aong these units, the process of sedientation is of prie iportance, because nearly 70% of water turbidity is reoved in this unit. Clarifiers help turbidity reoval, so different types of which are frequently used in water treatent plants; aong these the ost faous one is ulsator Clarifiers. This paper is aied at studying the suction height effect on turbidity reoval efficiency of water in ulsator. This ethod is investigated experientally by using a pilot scale odel. This pilot has a scale of :2 and is odeled on an actual ulsator with the capacity of 0. cubic eters per second. It was ade of plexi glass and to produce vacuu, a vacuu pup are used and for suction contact sensors are used. Keywords : ulsator- pulse clarification- turbidity reoval efficiency - contact sensors - suction height. GJRE- J Classification : FOR Code: A Study of the Suction Height Effect on Turbidity Reoval Efficiency of Water in ulsator Strictly as per the copliance and regulations of: 20 Seyed Mostafa Khezri, Elahe Dadvar & Heliasadat Hosseini Shekarabi.This is a research/review paper, distributed under the ters of the Creative Coons Attribution-Noncoercial.0 Unported License peritting all non coercial use, distribution, and reproduction in any ediu, provided the original work is properly cited.

2 A Study of the Suction Height Effect on Turbidity Reoval Efficiency of Water in ulsator Seyed Mostafa Khezri α, Elahe Dadvar & Heliasadat Hosseini Shekarabi ρ Abstract - In water treatent plants in ost countries around the world to achieve the desired standard of water quality, soe units such as grid chaber, coagulation, sedientation, clarification, filtration and disinfection are required. Aong these units, the process of sedientation is of prie iportance, because nearly 70% of water turbidity is reoved in this unit. Clarifiers help turbidity reoval, so different types of which are frequently used in water treatent plants; aong these the ost faous one is ulsator Clarifiers. This paper is aied at studying the suction height effect on turbidity reoval efficiency of water in ulsator. This ethod is investigated experientally by using a pilot scale odel. This pilot has a scale of :2 and is odeled on an actual ulsator with the capacity of 0. cubic eters per second. It was ade of plexi glass and to produce vacuu, a vacuu pup are used and for suction contact sensors are used. The result of experient shows that changes in suction height fro 4 to 2 centieter result in reduction of turbidity reoval efficiency fro 6/7 to 4/7. The ain reason of reduction or increase in turbidity reoval efficiency is ostly due to the foration of coarse and fine sedientary floc. Keywords : ulsator- pulse clarification- turbidity reoval efficiency - contact sensors - suction height. I. Introduction F ro past water resources have been an iportant factor in the foration of counities.thus people in sall and large groups gathered around the to settle. Factors such as population growth, higher deand for food, the necessity for iproveent for the health care and social welfare, industrial developent and protecting ecosystes, greatly contributed to the increase in water deand day by day. Nonetheless, today considering population boo and its subsequent consequences, naing, inadequate facilities, poverty and above all water shortage has created an insurountable proble for the societies. So, one of the ost iportant sectors in infrastructure developent is the anageent of water resources. Water supply and distribution in developing countries, created ajor probles and have ade governents Author α : An assistant professor of Environent and Energy faculty, Islaic Azad University, Science & Research branch, Tehran, Iran. E-ail : khezri4@gail.co Author σ : Graduate student in Environental Engineering Water Resources, Environent and Energy faculty, Islaic Azad University, Science & Research branch, Tehran, Iran. E-ail : Elahedadvar@yahoo.co Author ρ: Graduate student in Environental Engineering, Environent and Energy faculty, Islaic Azad University, Science & Research branch, Tehran, Iran. E-ail : hosseini.h.sh@gail.co invest huge sus of oney in it. Therefore, doing research project and focusing attention on the new solution to this proble is inevitable. In ost projects of water treatent plant, grid chaber units, priary sedientation, rapid ixing, coagulation, sedientation-filtration and disinfection are frequently used. ilot that is ade in this study was different fro that of in Mahidol University and the target is to study the effect of suction height on turbidity reoval efficiency in ulsator. After constructing the pilot, the rate of turbidity in input and output of ulsator was sapled and tested according to standard ethod. Grid chaber unit is a basin with suitable design for the deposition of aterial sedients in water. In water treatent plants with high capacity usually various copound settling pools are used, which are functionally different [-]. In these pools usually three operations: coagulation, flocculation and sedientation take place in one space and again contact of sludge is used to increase the settleent of suspended solids in the water [4-9]. ulsator is one of the water treatent plant units that are in the copound settling pool section with sludge blanket. In the pulsator coagulation and sedientation occur siultaneously in one container []. The only research on this topic was conducted by Surat Intrto in 200 at Mahidol University in Thailand. Although, Dereont -a French copanyhas been anufacturing atent ulsator for any years, little is known about the effects of variables on the efficiency of water turbidity reoval. Therefore ore research on the ipact of using ulsator on turbidity reoval efficiency needs to be undertaken. II. Materials and Methods In this experiental study, by changing the desired variables that is the suction height, the turbidity reoval efficiency rate of saples, taken fro ulsator input raw water and pure output water were easured based on TSS and saples turbidity according to 200 standard odel. Then, the results of these easureents were used in final analysis. This research was conducted in Tehran Science and Research Branch of Islaic Azad University. Since the ain objective of this study was to reveal that how the efficiency rate changes with the increase or decrease in suction height, to deterine the suction height in vacuu chaber contact ethod was used. In this ethod, water level can be easured 202 May 7Global Journal of Researches in Engineering Volue XII Issue vii Version I ( D) J 202 Global Journals Inc. (US)

3 A study of the suction height effect on turbidity reoval efficiency of water in pulsator Global Journal of Researches in Engineering ( D J ) Volue XII Issue vii Version I May through contacting a sensor with water surface. In this study three different sensors were used: one as reference, one for easuring axiu and another for easuring iniu height. Sensors were placed in different heights and each tie sapling was conducted fro the output and input of pulsator and reoval efficiency was calculated for each saple. a) Design of ulsator pilot For designing the pilot odel paying attention to geoetric or physical siilarity, and dynaic siilarity is essential [4-2]. Considering geoetric or physical siilarities, the odel is ade with the scale of.2 to the diensions of a real 0. cubic eter per hour ulsator. riary diensions for siulation, are ass (M), length (L), and tie (T). In the physical siilarity two strategies were considered that the first is the siilarity of particle settling oveent in ulsator pool and the second is the siilarity of ulsator pipe flow. For achieving the first, Froude nuber is fixed both in odel and prototype and for achieving siilar flow in pipes Reynolds nuber is fixed both in odel and prototype [0]. Table shows required paraeters of the kineatics siilarity in Froude odel law []. Table : Required paraeters of the kineatics siulation in Froude odel law [] Quantity )Length( L (Width) (Depth) (Area) (Volue) W D A V (Ideal retention tie) (Input flow) (Output flow) (Recycle Flow) Q i Q Q r T (Surface over flow) SOR (Average velocity) (Reynolds nuber) (Froude nuber) U Re Fr unit in /d /d /d /d /d Relations L / L W / W D / D A / A V / V T /T i Q /Q Q /Q Q /Q OFR r i r 2 /OFR U / U Re / Re 0 / Fr / Fr 2/ 2/ 2/ 0 / / 0 / roportions b) ilot construction For the construction of the pilot, the plate of lexi glass sheet with the thickness of 6, 8, and 0 is used. Total nuber of parts is 8, that are as follows:,0-thick sheets; 76, 8-thick sheets; 202 Global Journals Inc. (US) 0, 6-thick sheets; 88, -thick sheets; one input water pipe to ulstator (horizontal section); One input water pipe to ulstor (vertical section); One input water siphon to ulastor(vertical section)

9Global Journal of Researches in Engineering Volue XII Issue vii Version I A study of the suction height effect on turbidity reoval efficiency of water in pulsator one -eter, botto drain sludge pipe;

4 9Global Journal of Researches in Engineering Volue XII Issue vii Version I A study of the suction height effect on turbidity reoval efficiency of water in pulsator one -eter, botto drain sludge pipe; 2, botto drain sludge siphon; 7, botto drain sludge valve and other parts. Figure shows the scheatic diagra of experiental apparatus and figure 2 illustrates the testing pilot. Air tank 000 lit Vacuu pup Ground tank 00lit Figure : The Scheatic Diagra of Experiental Apparatus ( D) J 202 May Nutrition pup ulsator Vacuu chaber Figure 2 : Test ilot 202 Global Journals Inc. (US)

5 A study of the suction height effect on turbidity reoval efficiency of water in pulsator Global Journal of Researches in Engineering ( D J ) Volue XII Issue vii Version I May c) Electro-echanical equipent The following pieces of equipent were added to coplete the pilot. A one-inch raw water input pipe. Water flow control needle valve to ulsator. A 000-litre, raw water supply reservoir with echanical stirring added. Vacuu pup Solenoid valve to cut off and connect vacuu pup Needle valve to regulate air flow to vacuu breaker pup. roxiity sensors for setting the water level, in a vacuu chaber 24-volt feed source for supplying electric solenoid valve pinch valve to drain Hoper sludge electrical control systes including relays, tiers, and other equipent d) Nephloetry device For easuring turbidity, Nephloetry device with the following characteristics is used.. A Lovibond Neploetry device. 2. A two -Range Nephloetry device: 20 NTU and 200 NTU. A standard solution of 0.02 NTU e) Deterination of water level inside the vacuu chaber To deterine the water level inside the vacuu chaber there are various ethods that include: i. The contact ethods In the contact ethods fro contacting sensor to water, the height can be easured and sensors can be peranently installed at different heights. However, since the heights of the sensors used in this experient are adjustable any fewer sensors were needed. In this study, three different sensors are used one as reference, another to easure axiu and the last one to easure the iniu height. One of the disadvantages of using contact sensors is that they becoe dirty and consequently defunct. However, since they are econoically priced, coparing with non-contact sensors, they were preferred in this study. ii. The non-contact sensors Non-contact sensors usually work with radiation and through sending a wave and easuring the return tie they easure the height and length of the object aied at. These sensors are ore accurate than contact sensors and their reaction is uch better. III. Result The results of experient show that suction reoval efficiency increases with the increase in suction height. That is because, at heights with lower suction, the pulse created is lower so particles have a inial chance to collide with each other and subsequently the foration of large floc at lower suction height is not likely. In conclusion the reoval efficiency in this case is less. The changes are illustrated in chart. In tables 2,, 4, as described in previous section, the changes in turbidity reoval efficiency were easured in saples taken at three different heights. As can be seen in the chart at the suction height of 2 centieter the efficiency was 4.7%, at centieter it was 62.8% and at 4 centieter, it was 6.7%. So it is clear that efficiency changes curve over suction height is upward, in other word with the increase in the suction height the efficiency goes up accordingly. Table 2 : changes of the turbidity reoval efficiency at 4 centieter suction height Input NTU Output NTU Efficiency % Saple Saple Saple Saple Saple Saple Global Journals Inc. (US)

6 A study of the suction height effect on turbidity reoval efficiency of water in pulsator Table : changes of the turbidity reoval efficiency at centieter suction height Input NTU Output NTU Efficiency % Saple Saple Saple Saple Saple Saple May Table 4 : changes of the turbidity reoval efficiency at 2 centieter suction height Input NTU Output NTU Efficiency % Saple Saple Saple Saple Saple.2 8 Saple Global Journal of Researches in Engineering ( D) J Volue XII Issue vii Version I Chart : efficiency changes over tie 202 Global Journals Inc. (US)

7 A study of the suction height effect on turbidity reoval efficiency of water in pulsator Global Journal of Researches in Engineering ( D J ) Volue XII Issue vii Version I May IV. Conclusion and Recoendation As can be seen in diagra ; efficiency changing in relation to height-when the suction height increases so does the reoval efficiency. Optial suction height could be the subject of future research and it is possible that with the increase in suction height the fored flocs break down and result in the decrease in efficiency. This can be deduced fro coparison of curves at Different heights. The slope of the curve at the height of 2 to cs is uch ore than that of to 4 cs. It sees that the graph has a axiu and exceeding that figure, with the increase in suction height, the efficiency decreases. Different optial suction height can be the subject of Future research. If the pilot scale can be bigger, around., ore reliable results will be achieved. Siilarly, if the test is conducted on real scale, it will yield ore practical results. Moreover ultra sonic and gate valve sensors can replace touch sensors and needle valves respectively to increase the flexibility of the odel. Furtherore, instead of creating artificial turbidity real uddy water can be used since this, in turn, can sustain constant flow of turbid water to enter the ulsator. One of the probles and difficulties of this study was the high cost and lack of high-tech equipent which inevitably liited the testing points. Therefore, experients were perfored in only three points. V. Acknowledgeent I would like to extend y deep sense of gratitude to Tehran Water and Water Waste Copany for the financial support for this project and to officers of anageent iproveent and research office, especially Mr.Mojtahedi and Mr. Shiri. VI. Sources. Urban water supply, M.T.Monzavi, Tehran University, February Environental engineering, water and waste water treatent, Choupanglass.. Surface and underground water pollution, A.H.Javid, Azad University Tehran science and research branch, Environent and energy faculty. 4. Introduction to fluid echnics,jaes E.A. John University of Massachuset Willas Hall,Engle woodcliff. ulsatorclarifier/back to top- Mehdy asady,shrin alekpor,nj0762-edition 6. Basic water treatent - th edition the Open University set book Binne, - Iw publimartinkiber and George Sethurst 7. Water supply,chapter7 storage clarification and filtration of water Alanyaka& Malcol Jbranot -IWA publishing &Arenold 8. /water treatent advance pulsator clarifier/high rate pulsed sludge blanket clarifier / john clarifier/john D.Dyson, inflco degreont Inc.Richont,VA 9. / super ulsator clarifier 0. John.Jaes.E.A, Haberan.Willia.L, Introduction To Fluid Mechanics, rentice Hall, Englewood Cliffs, NJ0762. Taebi-Harandy.Air,Schroeder.Edward D. (999), Foration Of Density Current In Secodary Clarifier. 2. L. Koene, L.J.J. Janssen, Reoval of nickel fro industrial process liquids, Electrochi. Acta 47 () (200) X. Chen, Z. Wu, A new configuration of ebrane stack for retrieval of nickel absorbed in resins, J. Zhejiang Univ. SCI 6B (6) (200) L. Marder, A.M. Bernardes, J.Z. Ferreira, Cadiu electroplating wastewater treatent using a laboratory-scale electrodialysis syste, Sep. urif. Technol. 7 () (2004) Global Journals Inc. (US)

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