TFAWS Interdisciplinary Paper Session Performance evaluation of reverse

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TFAWS Interdisciplinary Paper Session Performance evaluation of reverse osmosis (RO) pre-treatment technologies for brackish

TFAWS Interdisciplinary Paper Session Performance evaluation of reverse osmosis (RO) pre-treatment technologies for brackish ground water (Ali I. Shehata, Mohamed Ismail, Ayman Abo-Bakr, Mohamed Abo El Azm) Presented By (Ayman Abo-Bakr) Thermal & Fluids Analysis Workshop TFAWS 2020 August 18 -20, 2020 Virtual Conference

List of contents • • Introduction Previous studies Case Study Objectives Experimental Setup Experimental

List of contents • • Introduction Previous studies Case Study Objectives Experimental Setup Experimental Results ROSA Software Comparison of Experimental Results against ROSA Results • Conclusion • References TFAWS 2020 – August 18 -20, 2020 2

Introduction • Desalination of brackish groundwater in Egypt has great potential with respect to

Introduction • Desalination of brackish groundwater in Egypt has great potential with respect to the availability of the resource. • All major aquifer systems in Egypt contain huge quantities of brackish groundwater. • The exploitation of this resource is still limited. With the current cheap price of brackish water desalination, there is a growing interest towards its exploitation. • Brackish water RO plants in Egypt confirm the potential of this solution. TFAWS 2020 – August 18 -20, 2020 3

Introduction • This paper presents the study of the effect of variation of different

Introduction • This paper presents the study of the effect of variation of different operating conditions on the performance of brackish groundwater RO unit. • This was achieved experimentally by using brackish water RO (Reverse Osmosis) desalination test rig. • Samples of experimental output parameters were used as ROSA input parameters to check the accuracy of experimental results. • However, there were deviations between the experimental results and ROSA results that did not exceed 10 %. TFAWS 2020 – August 18 -20, 2020 4

Introduction • Egypt falls in the North Africa, bordered on its northern coast by

Introduction • Egypt falls in the North Africa, bordered on its northern coast by the Mediterranean Sea and on its eastern coast by the Red Sea. • The main source of water in Egypt is the River Nile. [1] • Due to the rapid growth of the population and the increasing consumption of water in agriculture, industry, domestic use, etc. , it is expected that Egypt will rely to some extent on groundwater to develop the new projects [2]. • Brackish groundwater desalination is one of Egypt’s most potentially significant water resources. • Most aquifer systems in Egypt contain high quantities of brackish groundwater [3]. TFAWS 2020 – August 18 -20, 2020 5

Introduction The main aquifers in Egypt are generally formed as follow [4]: • •

Introduction The main aquifers in Egypt are generally formed as follow [4]: • • Nile valley aquifer (granular rocks) Nile delta aquifer (granular rocks) Moghra aquifer (granular rocks) Coastal aquifers (granular rocks) Nubian sand stone aquifer (granular rocks) Fissured hard rock aquifer (limestone rocks) Fissured and karstified aquifers (limestone rocks) TFAWS 2020 – August 18 -20, 2020 6

Introduction • The salinity of groundwater varies between 3000 and 5000 ppm. • Reverse

Introduction • The salinity of groundwater varies between 3000 and 5000 ppm. • Reverse osmosis is the finest level of filtration available [5]. • The RO membrane acts as a barrier to all dissolved salts and inorganic molecules, as well as organic molecules. TFAWS 2020 – August 18 -20, 2020 7

Previous Studies Several studies have been conducted : • Abou-Rayan et al studied the

Previous Studies Several studies have been conducted : • Abou-Rayan et al studied the effect of the feed water temperature, the feed pressure and the feed water salinity on the performance of a small-size BWRO desalination [7]. The increase of feed water pressure or temperature results in a recovery ratio increase. while the increase of feed water salinity leads to a decrease in recovery ratio. TFAWS 2020 – August 18 -20, 2020 8

Previous Studies Lilane D. Saifaoui 2019 [8] They concluded that the temperature of the

Previous Studies Lilane D. Saifaoui 2019 [8] They concluded that the temperature of the feed solution of the membrane desalination system has several effects: • when the temperature increases the diffusivity of the solute also increases. • desalination energy consumption decreases. TFAWS 2020 – August 18 -20, 2020 9

Previous Studies when the temperature increases the diffusivity of the solute also increases. TFAWS

Previous Studies when the temperature increases the diffusivity of the solute also increases. TFAWS 2020 – August 18 -20, 2020 10

Objectives TFAWS 2020 – August 18 -20, 2020 11

Objectives TFAWS 2020 – August 18 -20, 2020 11

Case Study The main study objective is to evaluate the performance of small scale

Case Study The main study objective is to evaluate the performance of small scale RO unit. This will be done by the following steps: • Practical Test Rig. • Theoretical performance estimation of RO unit using ROSA software. • Comparing experimental study against theoretical performance of the small scale RO unit. • Making regression analysis from the experimental results. TFAWS 2020 – August 18 -20, 2020 12

Experimental Setup The experimental test rig includes 150 experiments using brackish water at: -

Experimental Setup The experimental test rig includes 150 experiments using brackish water at: - • 6 different salinity, 1000, 2000, 3000, 4000, 5000 and 6000 ppm. • 5 different temperature 15, 20, 25, 30 and 35 °C • 5 different pressure 12, 16, 20, 24, 28 bar. The saline solution is prepared by dissolving a certain amount of sodium chloride in tap water to obtain the desired TDS. TFAWS 2020 – August 18 -20, 2020 13

Experimental Setup Fig (1. 1) Reverse Osmosis test rig schematic TFAWS 2020 – August

Experimental Setup Fig (1. 1) Reverse Osmosis test rig schematic TFAWS 2020 – August 18 -20, 2020 14

Experimental Setup Fig (1. 2) Reverse Osmosis test rig TFAWS 2020 – August 18

Experimental Setup Fig (1. 2) Reverse Osmosis test rig TFAWS 2020 – August 18 -20, 2020 15

Experimental Results increasing feed water pressure increasing feed water TDS increases the permeate flow

Experimental Results increasing feed water pressure increasing feed water TDS increases the permeate flow rate. decreases permeate flow rate. • due to increasing of water density and viscosity as well, that passes through the membrane of the tested R. O. unit as shown in figure (2). TFAWS 2020 – August 18 -20, 2020 16

Experimental Results increasing feed water TDS increases brine flow rate. • This is due

Experimental Results increasing feed water TDS increases brine flow rate. • This is due to decreasing permeate stream that comes out from the membranes of the tested R. O. unit as shown in figure (3). TFAWS 2020 – August 18 -20, 2020 17

Experimental Results decreasing feed water TDS RR & permeate flow rate increase. • This

Experimental Results decreasing feed water TDS RR & permeate flow rate increase. • This is due to increasing permeate stream that comes out from the membranes of the tested R. O. unit as shown in figure (4). TFAWS 2020 – August 18 -20, 2020 18

Experimental Results by increasing the membrane salt rejection permeate TDS decreases by decreasing feed

Experimental Results by increasing the membrane salt rejection permeate TDS decreases by decreasing feed water TDS permeate TDS decreases • This is due to increasing the membrane salt rejection of the tested R. O unit as shown in figure (5). TFAWS 2020 – August 18 -20, 2020 19

Experimental Results increasing the permeate flow rate SEC decreases increasing feed water TDS SEC

Experimental Results increasing the permeate flow rate SEC decreases increasing feed water TDS SEC increases • This is due to decreasing permeate stream that comes out from the membranes of the tested R. O. unit as shown in figure (6). TFAWS 2020 – August 18 -20, 2020 20

Results and Discussions Effect of changing feed water pressure and temperature • At constant

Results and Discussions Effect of changing feed water pressure and temperature • At constant feed water flow = 1 m 3/hr, constant feed water TDS = 5000 ppm • by changing feed water temperature at 15, 20, 25, 30, 35°C, • feed water pressure ranging from 12 to 28 bar and by increasing the feed water pressure leads to: increasing feed water pressure increases the permeate flow rate. TFAWS 2020 – August 18 -20, 2020 21

Experimental Results increasing feed water temperature increases the permeate flow rate. • Due to

Experimental Results increasing feed water temperature increases the permeate flow rate. • Due to increasing the membrane spacing that reduces the flow resistance and helps in a wider spacing area to allow feed water to pass through as shown in figure (7). TFAWS 2020 – August 18 -20, 2020 22

Experimental Results increasing the permeate flow rate increasing feed water temperature brine flow rate

Experimental Results increasing the permeate flow rate increasing feed water temperature brine flow rate decreases. • This is due to increasing permeate stream that comes out from the membranes of the tested R. O. unit as shown in figure (8). TFAWS 2020 – August 18 -20, 2020 23

Experimental Results by increasing the permeate flow rate by increasing feed water temperature •

Experimental Results by increasing the permeate flow rate by increasing feed water temperature • recovery ratio increases This is due to increasing permeate stream that comes out from the membranes of the tested R. O. unit as shown in figure (9). TFAWS 2020 – August 18 -20, 2020 24

Experimental Results by increasing the membrane salt rejection by decreasing feed water TDS permeate

Experimental Results by increasing the membrane salt rejection by decreasing feed water TDS permeate TDS decreases • This is due to increasing the membrane salt rejection of the tested R. O unit as shown in figure 10). figure (10). TFAWS 2020 – August 18 -20, 2020 25

Experimental Results increasing the permeate flow rate increasing feed water temperature SEC decreases •

Experimental Results increasing the permeate flow rate increasing feed water temperature SEC decreases • This is due to decreasing permeate stream that comes out from the membranes of the tested R. O. unit as shown in figure(11). figure (11). TFAWS 2020 – August 18 -20, 2020 26

ROSA Software The Reverse Osmosis System Analysis (ROSA) computer program calculates : • The

ROSA Software The Reverse Osmosis System Analysis (ROSA) computer program calculates : • The feed pressure • Permeate quality • The operating data of all individual elements. It is easy to optimize the system design by changing the number and type of elements and their arrangement. Steps to use ROSA : • Defining project information • Identify feed water source • Feed water type and analysis • Feed water pretreatment and filtration TFAWS 2020 – August 18 -20, 2020 27

ROSA Software • Defining project information : Project name , date and description. TFAWS

ROSA Software • Defining project information : Project name , date and description. TFAWS 2020 – August 18 -20, 2020 28

ROSA Software • Identify feed Water type, TDS and temperature TFAWS 2020 – August

ROSA Software • Identify feed Water type, TDS and temperature TFAWS 2020 – August 18 -20, 2020 29

ROSA Software • System Configuration: membranes, flow rate and RR TFAWS 2020 – August

ROSA Software • System Configuration: membranes, flow rate and RR TFAWS 2020 – August 18 -20, 2020 30

ROSA Software • Report: TFAWS 2020 – August 18 -20, 2020 31

ROSA Software • Report: TFAWS 2020 – August 18 -20, 2020 31

Comparison of Experimental Results against ROSA Results • Software ROSA was used for testing

Comparison of Experimental Results against ROSA Results • Software ROSA was used for testing the accuracy of experimental results where a sample case was taken at feed water TDS=6000 ppm. • Feed water flow rate, TDS and pressure were taken as input parameters for ROSA software at feed water Temperature = 25 C. • The output parameters (permeate flow rate, brine flow rate, recovery ratio, permeate TDS and SEC) resulted from ROSA were taken to make a comparison against the experimental results. • However, there were deviations between the experimental results and ROSA results that did not exceed 10 %, for both experimental and ROSA results increasing in feed water pressure leads to: TFAWS 2020 – August 18 -20, 2020 32

Comparison of Experimental Results against ROSA Results • Increasing in permeate flow rate :

Comparison of Experimental Results against ROSA Results • Increasing in permeate flow rate : the average deviation between experimental permeate flow rate and ROSA permeate flow rate at the lowest feed water pressure of 12 bar was 10% • while at the highest value of feed water pressure of 28 bar the average deviation was 7% as shown in figure (12). Figure (12) TFAWS 2020 – August 18 -20, 2020 33

Comparison of Experimental Results against ROSA Results • Decreasing in brine flow rate, the

Comparison of Experimental Results against ROSA Results • Decreasing in brine flow rate, the average deviation between experimental brine flow rate and ROSA brine flow rate at the lowest feed water pressure of 12 bar was 3% • while at the highest value of feed water pressure of 28 bar the average deviation was 8% as shown in figure (13). Figure (13) TFAWS 2020 – August 18 -20, 2020 34

Comparison of Experimental Results against ROSA Results • Increasing in recovery ratio, the average

Comparison of Experimental Results against ROSA Results • Increasing in recovery ratio, the average deviation between experimental recovery ratio and ROSA recovery ratio at the lowest feed water pressure of 12 bar was 10%, • while at the highest value of feed water pressure 0 f 28 bar the average deviation was 7% as shown in figure (14). Figure (14) TFAWS 2020 – August 18 -20, 2020 35

Comparison of Experimental Results against ROSA Results • Decrease in permeate TDS, the average

Comparison of Experimental Results against ROSA Results • Decrease in permeate TDS, the average deviation between experimental permeate TDS and ROSA permeate TDS at the lowest feed water pressure of 12 bar was 32 ppm • while at the highest value of feed water pressure 0 f 28 bar the average deviation was 25 ppm as shown in figure (15). Figure 15 TFAWS 2020 – August 18 -20, 2020 36

Comparison of Experimental Results against ROSA Results • Decreasing in SEC, the average deviation

Comparison of Experimental Results against ROSA Results • Decreasing in SEC, the average deviation between experimental SEC and ROSA SEC at the lowest feed water pressure of 12 bar was 10% • while at the highest value of feed water pressure of 28 bar the average deviation was 6% as shown in figure (16). Figure (16) TFAWS 2020 – August 18 -20, 2020 37

Conclusion • The following conclusions for the effect of feed water pressure can be

Conclusion • The following conclusions for the effect of feed water pressure can be obtained for permeate water produced, brine rejected, recovery ratio, permeate TDS and specific power consumption at different feed water TDS, feed water temperature: • At constant feed water TDS and temperature by increasing feed water pressure the permeate flow rate and the recovery ratio increase. while brine rejected, permeate TDS and specific power consumption decrease. • At constant feed water pressure and temperature by increasing feed water TDS the permeate flow rate and the recovery ratio decrease. while brine rejected, permeate TDS and specific power consumption increase. TFAWS 2020 – August 18 -20, 2020 38

Conclusion • At constant feed water pressure and TDS by increasing feed water temperature

Conclusion • At constant feed water pressure and TDS by increasing feed water temperature the permeate flow rate, permeate TDS and the recovery ratio increase. while brine rejected, and specific power consumption decrease. TFAWS 2020 – August 18 -20, 2020 39

REFERENCES [1] Ahmed R. Allam, Ele-Jan Saaf, Mohamed A. Dawoud, "Desalination of brackish groundwater

REFERENCES [1] Ahmed R. Allam, Ele-Jan Saaf, Mohamed A. Dawoud, "Desalination of brackish groundwater in Egypt", Desalination, 152 (2002) 19– 26. [2] M. R. El Tahlawi , A. A. Farrag , S. S. Ahmed, " Groundwater of Egypt: ‘‘an environmental overview’’, Environmental Geology , August 2008. [3] Mariam G. Salim, "Selection of groundwater sites in Egypt, using geographic information systems, for desalination by solar energy in order to reduce greenhouse gases", Advanced Research, (2012) 3, 11 -19. [4] Kamal Hefny, M. Samir Farid and Mohamed Hussein, " Groundwater assessment in Egypt", Water Resorces Development, Volume 8 Number 2, June 1992. TFAWS 2020 – August 18 -20, 2020 40

REFERENCES [5] Mohamed Ismail, Abd El-Hamid Attia, Samy El-Sherbiny, "Performance Evaluation of Small Scale

REFERENCES [5] Mohamed Ismail, Abd El-Hamid Attia, Samy El-Sherbiny, "Performance Evaluation of Small Scale RO Unit", International Journal of Mechanical and Production Engineering, Volume- 6, Issue(4), 2018. [6] S. Suleiman, A. Meree, M. AL-Shiakh, F. Kroma, "Performance of RO plant with solar preheated feed water", Desalination and Water Treatment, 28 (2011) 345– 352. [7] Berge Djebedjian, Helmy Gad, Ibrahim Khaled, Magdy Abou Rayan, “An Experimental investigation on the operating parameters affecting the performance of reverse osmosis desalination system, ” Tenth International Water Technology Conference. , 2006, Alexandria, Egypt. [8] Lilane, A. , Saifaoui, D. , Hariss, S. , Jenkal, H. , & Chouiekh, M. (2019). Modeling and simulation of the performances of the reverse osmosis membrane. Materials Today: Proceedings TFAWS 2020 – August 18 -20, 2020 41