WATER CHEMICAL ANALYSIS FOR DIFFERENT …uob.edu.ly/assets/uploads/pagedownloads/05f68-tobruk... · · 2016-11-10chemical analysis was carried out for pH value, electrical conductivity

The 13th International Conference on Materials Science and its Applications in Oil and Gas Industries, Benghazi-Libya (Aug. 26-27. 2013), P. 172-192

271

WATER CHEMICAL ANALYSIS FOR DIFFERENT STAGES IN

TOBRUK DESALINATION PLANT

MABROUK M. SALAMA

1, SAAD K. EL EBAIDI

2 AND DAVID P.STICKLEY

3

1Department of chemistry, University of Benghazi, Benghazi –Libya

2Department of Earth Sciences, University of Benghazi, Benghazi, Libya

3Bawareg Industrial Company for Chemicals, Benghazi – Libya

Corresponding Email: [email protected]

ABSTRACT

There are different stages for water treatment in the Desalination Plant. The multi-effect desalination thermo

compressor (MED) type of desalination process, is the chosen type in Tobruk Plant. This plant includes sea-

water intake, chlorination system, evaporator units, boilers, chemical treatment units, and Drinking Water tanks.

In this paper, eleven (11) water samples were taken from the different stages, in the Desalination Plant. The

chemical analysis was carried out for pH value, electrical conductivity (E.C), total dissolved solids (T.D.S),

alkali and alkaline earth metals, heavy metals, halogens, nitrates, sulphates, and phosphates. The analytical

results for these stages were assessed according to the Libyan National and World Health Organisation (WHO)

Water Quality Standards. The samples all complied with both sets of Water Quality Standards, resulting in

overall compliance with the standards. These results are acceptable as Public Drinking Water Product water

stream.

INTRODUCTION

Libya is among the world's most water-scarce areas. Almost all available water resources

have been mobilized. Libya has responded to water scarcity through the development of

specialized water institutions, with extensive investments in water infrastructures including

ground water sources, the man-made river project, and desalination plants [1].

Municipal water supply has been among Libyans top development priorities. Improvements

including water quantity as water treatments plants and desalination plants were installed

with more stress on better service quality through improved operation and maintenance

practices.

The desalination industries are considered to have a major role in development of human life.

The Libyan coastline extends for (1950 km) along the southern coast of the Mediterranean

Sea, the desalination plant projects are considered as one of the important projects for water

resources in Libya, especially for the northern coastline which has the biggest population and

more water demand for drinking water and industrial purposes [2].

Mabrouk M. Salama, Saad K. El Ebaidi and David P.Stickley

271

WATER RESOURCES IN LIBYA

Municipal water demand in Libya has increased markedly in the last 4 decades in response to

high population growth rates and increased per capita requirements. Water use rates in Libya

vary from 150 to over 450 liters per day. The main water resources in Libya are ground

water aquifers, man-made river, or desalination water uses. Practically, all municipal water

has been supplied from local large basins in the south via MMRP. Desalination contributed

less than 15 % of the total municipal water used. Desalinated Water uses have been limited

to coastal areas, where ground water supplies or quality problems exist. Quantitatively; a

total volume of about 1.81 Mm3/day was supplied in 2009. Almost one Mm3/day were

supplied from the MMRP and 0.53 Mm3/day from local ground water aquifers with

desalination plants supplying the remaining 0.28 Mm3/day [1].

DESALINATION WATER QUALITY STANDARDS

The World Health Organization (WHO) states that a permissible salinity limit for potable

drinking water is in the range from 500 mg/l to 1,000 mg/l under limited concentration [3].

The US Environmental Protection Agency (USEPA) states that drinking water with T.D.S

greater than 500 mg/l can be distasteful.

Requirements and conditions involved in choosing desalination technologies and

techniques

The main important factors when choosing the suitable desalination technologies and

techniques are [2]:

1. Geographic study of the region.

2. Topography of the site.

3. Capacity requirements and plant size.

4. Type and cost of fossil fuel energy available.

5. Condition of local infrastructure, including ability to plug into electricity grid.

6. Quality control study of feeding water (T.D.S concentration).

7. The cost of product water.

Desalination technologies and techniques

A desalination process essentially separates salt water into two parts, one that has a low

concentration of salt (treated water or product water), and the other with a much higher

concentration than the original feed water, usually referred to as brine concentrate. The two

major types of technologies that are used around the word for desalination can be broadly

classified as thermal or membrane [4,5]. The major desalination techniques are identified in

Table (1).


271

Table 1. Desalination technologies and processes.

Thermal technology Membrane

Multi-stage flash Distillation (MSF) Reverse Osmosis (R.O)

Multi-Effect Distillation (MED) Electrodialysis (E.D)

Vapor Compression Distillation (VCD) Electrodialysis reversal (E.D.R)

Within those two categories, there are sub-categories using different techniques as follows:

(i) Thermal Technologies

Thermal technologies, as the name implies involve the heating of sea water and collecting the

condensed vapour (distillate) to produce pure water. They have been used for sea water

desalination [6] and can be divided into three groups:

1. Multi - Stage Flash distillation (MSF)

This process involves the use of distillation through several (multi - stage) chambers. In the

MSF process each successive stage of the plant operates at progressively lower pressures.

The feed water is first heated under high pressure and is led into the first flash chamber,

where the pressure is released causing the water to boil rapidly resulting in sudden

evaporation or flashing. This flashing of a potion of the feed continues in each successive

stage, because the pressure at each stage is lower than in the previous stage. The vapour

generated by the flashing is converted into fresh water by being condensed on heat exchanger

tubing that run through each stage. The tubes are cooled by the incoming cooler feed water

[1].

- MSF is the most dominant in the thermal category.

- MSF is capable of very large yield.

- It operates using a series of 4 to 40 chambers or stages.

- MSF operates at top brine temperatures of 90 - 120 oC.

- Capital and energy costs are the highest of all desalination technology.

2. Multi Effect Distillation (MED)

Multi effect distillation occurs in a series of vessels (effects) and uses the principles of

evaporation and condensation at reduced ambient pressure. In multi - effect distillation, a

series of evaporator effects produce water at progressively lower pressures. Water boils at

low temperatures as pressure decreases, so the water vapour of the first vessel or the second

and so on. The more vessels or effects there are, the higher the performance ratio. Depending

upon the arrangement of the heat exchanger tubing, MED units could be classified as

horizontal tube, vertical tube or vertically stacked tube bundles.


271

3. Vapor Compression Distillation

The vapour compression distillation (VCD) process is used either in combination with other

processes such as the M E D or by itself. The heat for evaporating the water comes from the

compression of vapour, rather than the direct exchange of heat from steam produced in a

boiler. The VC units are generally small in capacity, and are often used at hotels, resorts and

in industrial applications.

(ii) Membrane technologies

Membrane technology can be subdivided into three categories:

Reverse Osmosis (RO), electro-dialysis (ED), and electro-dialysis reversal (EDR).

1. Reverse Osmosis (R.O)

Reverse osmosis process uses pressure as the driving force to push saline water through semi-

permeable membrane into a Product water stream and a concentrated brine stream [7].

- R.O. is the most dominant membrane desalination

- R.O. has four subsystems

- Pre-treatment

- High pressure pump

- Membrane modules

- Post-treatment

- R.O. has low capital cost but significant maintenance.

2. Electro-dialysis (E.D), and (3) Electro-dialysis reversal (EDR)

- E.D is a low cost method for brackish water desalination

- E.D produces water around 20 ppm T.D.S

- EDR unit generally operates on the same principle as an ED unit.

OBJECTIVES OF THIS STUDY

The aim of this study is to measure the water chemical analysis of each stages of Tobruk

desalination plant with emphasis in drinking water produced with accordance to Libyan and

WHO standards, as well as to measure any pollutants such as heavy metals and their effects

on the desalination components and testing of the chemical additional efficiency to prevent

scale formation and corrosions.

STUDY AREA

Samples have been taken for 11 sampling points, each one represent different component of

the Tobruk MED desalination plant. This plant was established in 2003 by Sidem French

Company.


271

ANALYSIS AND EXPERIMENTAL WORK

Samples have been taken for 11 samples, each one represent different stage in the plant. The

collected samples were chemically analysed to find the concentration of alkali metals, heavy

metals, nitrates, sulphates, phosphates and chlorides in the Bawareg Industrial Company for

Chemicals, private laboratory.

Using flame photometer and Spectrophotometer, all the analyses were performed according

to standard methods.

Sample Data

1/Sea water Sample # T1

Result unit Tests Sample

81 °C Temperature Sea Water

0817 pH

58,200 S / cmµ E.C. Place of taking

sample

22,000 mg / 1 Cl In take

787 mg / 1 Free Cl

7880 mg / 1 Br Condition of

taking sample

7871 mg / 1 NH3 Without

treatment

2/ Chlorination Sample # T2


81 °C Temperature Sea Water

08.7 pH Place of taking

sample

58,200 S / cmµ .E.C In take

787 mg / l Free Cl

078177 mg / l Cl Condition of

taking sample

7870 mg / l Br Shock injection


277

3/ Chlorination Unit Sample # T3

Result Unit Tests Sample

19 °C Temperature Solution of

NaOCl

0810 pH

58,200 S / cmµ E.C. Place of taking

sample

08077 mg / 1 Cl Condition cell

881 mg / 1 Free Cl

78.0 mg / 1 Br Condition of

taking sample

During unit

running

4 /Water distillate Sample # T4


01 °C Temperature Water of

Distillate

18.0 pH

11 S / cmµ . E.C Place of taking

sample

787. mg / 1 Br Condition cell

0080 mg / 1 T.D.S Condition of

taking sample

17 mg / 1 Cl During unit

runing


271

5/ Water distillate after injection of CO2 Sample # T5


26 °C Temperature Water distillate

after injection of

CO2

0801 pH

870 S / cmµ E.C. Place of taking

sample

After injection of

CO2

Condition of taking

sample

During unit running


271

6/ Drinking water Sample # T6


26 °C Temperature Drinking

Water

0807 pH

800 S / cmµ E.C. Place of taking

sampl

07 mg / 1 Total hardness After treatment

of Ca CO3

87180 mg / 1 T.D.S

07 mg / 1 Na

0 mg / 1 K Condition of

taking sample

0800 mg / 1 Mg During unit

runnin

80 mg / 1 Ca

78. mg / 1 -

F

0080 mg / 1 Cl-

7878 mg / 1 Br

7878 mg / 1 NH3

7878 mg / 1 NO3

8.81 mg / 1 SO4

88.00 mg / 1 PO4

787 mg / 1 Mn

787. mg / 1 Fe

887 mg / 1 Cu

787 mg / 1 Al


211

7/ Boiler water feed Sample # T 7


33 °C Temperature Water feed

3.0 S / cmµ E.C

0.5 mg / 1 Total hardness Place of taking

sample

0810 pH Water feed

88.0 mg / 1 T.D.S

080 mg / 1 D.O Condition of

taking sample

1.0> mg / 1 Cl During working

unit

7878 mg / 1 Fe

787 mg / 1 Cu

.810 mg / 1 Si

7800 mg / 1 PO4


212

1/ Boiler Water feed NO.81 S/by Sample no # T 1

Result Unit Tests Sample

00 °C Temperature Water Boiler

0810 pH

87 µS/cm Conductivity Place of taking

sample

0 mg / 1 T. hardness From Boiler

.88 mg / 1 T.D.S

01 mg / 1 CI Condition of

taking sample

78. mg / 1 PO4 During unit

running

780 mg / 1 Cu

.870 mg / 1 Si

7878 mg / 1 Fe

7180 mg / 1 SO4

88810 mg / 1 NO3

SO3

17 mg / 1 Methyl alkali.

.7 mg / 1 Ph ph alkali.


211

9/ Boiler water NO . 82 In – service Sample # T9


.0 °C Temperature Water Boiler

878.7 pH

80. µS/cm Conductivity Place of taking

sample

787 mg / 1 T.hardness From Boiler

mg / 1 T.D.S

880870 mg / 1 Cl

8781 mg / 1 PO4 Condition of

taking sample

787 mg / 1 Cu During unit

running

7800 mg / 1 Si

787 mg / 1 Fe

0.80 mg / 1 SO4

7878 mg / 1 NO3

mg / 1 SO3

871 mg / 1 Na

07 mg / 1 K

70 mg / 1 Methy

ALKALI

07 mg / 1 PH PH alkali


211

10/ Boiler water NO . 83 In – service Sample # T10


.0 °C Temperature Water Boiler

87800 pH Place of taking

sample

80. S / cmµ Conductivity Boiler Water

787 T.hardness

078880 mg/l T.D.S

8880 mg / 1 Cl Condition of

taking sample

00871 mg / 1 PO4 During unit

running

7880 mg / 1 Cu

7870 mg / 1 Si

008. mg / 1 Fe

787 mg / 1 SO4

80. mg / 1 NO3

. mg / 1 Na

mg/l K

07 mg / 1 PH PH

877 mg / 1 M .Value


211

11/ After addition of Na2 SO3: Sample # T11


.0 °C Temperature Water Sea

0811 pH

0187 S / cmµ Conductivity Place of taking

sample

00177 mg / 1 CI After

Hypo chloride

treatment

107 mg / 1 SO4

7878 mg/l Br

mg / 1 D.O Condition of

taking sample

08118 mg / 1 NO3 During unit

running

mg/l SO3

Residual chlorin

DISCUSSIONS

As part of a routine sampling operation, water samples were taken from the available sample

points in Tobruk Desalination plant. Field Analysis was carried out a t all sample points and

recorded. The field analysis included pH value, temperature (in degree C), electrical

conductivity (E.C, in µS/cm), and free and total chlorine where appropriate. The remaining

analyses were performed on the sample bottles which were transported to the laboratory in

cool boxes. The analytical data has been assessed for the Libyan National and World Health

Organization (WHO) Water Quality Standards. All samples complied with these standards;

therefore these sample results are acceptable as Public Drinking Water.


211

Sample Analyses Result

1. Sea-Water Intake (T1)

The Mediterranean sea-water is pumped into the Tobrouk MED Desalination Plant (Figure

1a), via the sea-water intake. The analytical results are within the expected ranges for Eastern

Mediterranean sea-water, shown in Table 2:

Table 2. Eastern Mediterranean Sea - Water Chemical Analysis.

Parameter Normal Seawater Eastern Med. Result*

pH value 8.1 7.8 – 8.2 7.8

Temperature (oC) 18 22.59 -23.59 21

E.C µS/cm 58,000 58,200

T.D.S 34,483 38,600 37,903

Ca 411 411 - 416 412

Mg 1,262 1,403 1,284

Na 10,556 11,800 10,800

K 380 500 399

Fe 0.0034 0.028 – 0.0437 0.324

Cl-

18,980 21,200 22,000

NO3-

3.81 – 5.29

3.81

SO42-

2,649 2,950 2,701

F- 1.0 1.0

SiO2 2.9 1.58 – 2.29 2.3

PO43-

0.18 – 0.25 0.088

B 4.45 4.5

Br- 67.3 65 67

NH4+ 0.60 – 0.73 0.08

Total Hardness 6,222.3 6,815.4 6,317.5

Total Alkalinity 115 133 118.9

HCO3- 140 162 145

Free Chlorine 0.0 0.0 0.0 __________________________________________________________________________________ Result* - chemical data for Tobruk sea-water intake.


211

Excepting the first three parameters in Table 2, the remaining parameters are in

concentrations of mg/l.

The total hardness and total alkalinity results are in mg/l as CaCO3.

Since the Mediterranean Sea is generally enclosed from other oceans, the soluble salt

content is slightly greater than open sea water. For example, the sodium chloride content

for the Eastern Mediterranean is about 11.7 % greater than normal sea water.

The pH value of the sea water taken from the Eastern Mediterranean at the Tobrouk

Desalination Plant is 7.8, with temperature 18oC. The general mineral metals are at the

expected concentrations, with sodium highest at 10,784 mg/l as Na. The corresponding

chloride is 22,000 mg/l as Cl- , with sulphate at 2,701 mg/l as SO42- , bicarbonate at 145

mg/l, and bromide at 67 mg/l as Br-. These analyses are at the expected concentrations in

the Eastern Mediterranean. This water is primarily filtered to remove all gross suspended

matter.

1. Chlorination (T2 and T3)

The pumped sea water is initially chlorinated to remove all bacteria, algae, and all living

matter (Figure 1b). Chlorination is achieved using pumped sodium hypochlorite solution

(8% , bleach). The resulting free chlorine was 1.8 mg/l with a pH value of 7.85, and

temperature = 19 oC.

2. Water Distillate (T4)

The process of water distillation produces purified water that is largely free of dissolved

anions and cations that are removed from the sea water (Figure 1c). However, some

chloride ions are also allowed through this process possibly due to splashing. The pH

value of water distillate was 8.36 with a temperature of 28 oC, chloride of 80 mg/l, and

electrical conductivity of 88 µS/cm.

The water distillate was then injected with carbon dioxide, which alters the pH value to

5.28 (see T5). The reactions of CO2 with water are as follows:

i) CO2(g) === CO2 (l)

At room temperature and pressure, the solubility of CO2 is about 90 cm3 of CO2 per 100

ml of water (cl/cg = 0.8).

ii) CO2(l) + H2O === H2CO3 (l)

This is a slow reaction, only 0.2 – 1% of dissolved CO2 is converted to

H2CO3 . However, it is sufficient to change the pH value quite

Appreciably from 8.36 to 5.28. The water distillate is now able to react

with silica gravel (limestone; Figure 1d) in several tanks. The limestone is in the form of

small diameter nodules:

H2O + CO2 + CaCO3=== Ca(HCO3)2


217

During this reaction, the pH value is partly neutralised to pH = 6.64. The water distillate after

chlorination and CO2 injection followed by reaction with silica gravel (limestone), is

collected into the Tobrouk water tanks, known as the Tobrouk reservoir (see T6).

Figure 1. a) MED Desalination Plant; b) Chlorination unit; c) Evaporators;

d) Limestone tanks

3. Drinking Water (T6)

The distilled water, after CO2 injection and reaction with the silica gravel (limestone), is

piped to the water tanks. The chemical analytical results are shown in Table 3, with the

equivalent WHO Water Quality Standards.


211

Table 3. Drinking Water Analytical Results

Parameter Drinking Water, T6

analytical result

Drinking Water WHO

Standards

pH value 6.64 6.5 – 8.5

Temperature, oC 26 NGV

Electrical conductivity

µS/cm(EC)

165 1,500

Total dissolved solids,

TDS mg/l

146.1 1,200 mg/l

Total hardness 50.0 500 mg/l as CaCO3

Total alkalinity 45.6 -

Hydrogen sulphide 0.0 Not detectable

Calcium mg/l 16 -

Magnesium mg/l 6.76 -

Sodium mg/l 18.4 200 mg/l

Potassium mg/l 2.0 -

Ammonia/N mg/l 0.01 0.5 mg/l

Bicarbonate mg/l 55.6 -

Chloride mg/l 28.4 250 mg/l

Sulphate mg/l 13.8 500 mg/l

Nitrate mg/l 0.01 50 mg/l

Nitrite mg/l 0.0 0.2 mg/l

Phosphorus as PO43- mg/l 1.325 -

Fluoride mg/l 0.3 1.5 mg/l

Free Chlorine mg/l 0.2 5.0 mg/l

Iron mg/l 0.03 0.3 mg/l

Manganese mg/l 0.0 0.4 mg/l

Silicon as SiO2 3.4 NGV

Bromide mg/l 0.01 0.01 mg/l

Total Coliforms nil nil

E. Coli nil nil

NGV = no guide value.

All of the parameters that were analysed for the Tobrouk Desalination Plant Drinking Water

production complied with the WHO Standards. This is also true for the Libyan Water Quality

Standards (Tables 4 and 5). Therefore, the Production Drinking Water is considered to be

portable and of Water Quality Standard.

The analytical data has given an acceptable ionic balance between anions and cations.

Therefore, the analysis is also acceptable.

The microbiological data gave nil number for total Coliforms and E.Coli. The free chlorine

result was 0.2 mg/l which is acceptable for potable water.


211

Table 4. Chemical Analyses for the Manufacturer (SIDEM Co.)

Portable

water

Distilled

water

Seawater Unit Parameter

081 080 08. mg / 1 pH

80. 00 41,299 mg / 1 T.D.S

.881 08.0 13,481 mg / 1 Na+

8881 8881 22,733 mg / 1 CI-

7800 7800 700 mg / 1 K+

7810 7810 80.. mg / 1 Mg++

.08. 7800 0.8 mg / 1 Ca+

88.0 88.0 .008 mg / 1 SO4-


211

Table 5. Libyan standard drinking water, the chemical compounds standard for drinking water

1200 Ms/cm 750 Ms/cm E.C 1

5.8 5.8 pH 0

500 mg/l 200 mg/l Total hardness .

1000 mg/l 500 mg/l T. D. S 7

400 mg/l 200 mg/l Sulphates 0

250 mg/l 200 mg/l Chloride 0

200 mg/l 20 mg/l Sodium 0

1 mg/l 0.01 mg/l Copper 1

200 mg/l 75 mg/l Calcium .

150 mg/l 30 mg/l Magnesium 87

40 mg/l 10 mg/l Potassium 88

15 mg/l 5 mg/l Zinc 80

1.5 mg/l 1 mg/l Fluoride 8.

0.3 mg/l 0. 1 mg/l Iron 87

0.1 mg/l 0.05 mg/l Manganese 80

0.2 mg/l 0 Aluminum 80

4. Boiler Water Feed (T7)

The boiler feed water had temperature 33 oC, pH value = 7.86, TDS = 1.95 mg/l, and

electrical conductivity = 3.0 µS/cm. The boiler feed water also has phosphate added to

prevent precipitation in the boilers. Oxygen is removed by use of sodium sulphite addition.

Dissolved oxygen reacts with sodium sulphite as follows:


212

2Na2SO3 + O2=== 2Na2SO4

Dissolved oxygen, when present, will cause severe corrosion in boilers, hence its removal.

5. Boiler Water No. 81 (T8) (In stand-by)

Since this boiler is on stand-by, the pH value is 6.82, phosphate is 0.3 mg/l, TDS = 9.1, EC =

14 µS/cm, and chloride = 6.8 mg/l.

6. Boiler Water No.82 (T9) (in service)

This boiler is in operation. The pH value has been increased substantially to 10.34, and is

quite alkaline. The phosphate is 26.85 mg/l following addition of sodium phosphate to

prevent corrosive action, TDS = 112.45 mg/l, chloride = 14.8 mg/l, and sulphate 59.5 mg/l,

Nitrate is very low in concentration. The alkalinity is 45 mg/l as CaCO3, and phenolphthalein

alkalinity is 20 mg/l as CaCO3. The chloride concentration is 14.8 mg/l.

7. Boiler Water No.83 (T10) (in service)

This boiler is also in operation. The pH value is also increased to 10.66, and is alkaline. The

phosphate concentration is 27.48 mg/l after addition of sodium phosphate for preventing

corrosion, the TDS = 241.15 mg/l which is quite high compared with boiler No. 82. And

nitrate is also very low.

The alkalinity is 100 mg/l as CaCO3, and phenolphthalein alkalinity is 70 mg/l as CaCO3.

The chloride concentration is 11.6 mg/l.

In both boilers, the iron concentration is very low, < 0.01 and 0.02 mg/l for boilers 82 and 83

respectively.

Both boilers have greater sulphate concentrations at 59.5 mg/l, and 65.9 mg/l respectively for

boilers 82 and 83 respectively. This is due to the addition of sodium sulphite to remove

dissolved oxygen and prevent serious corrosion problems (see sample T11). This addition is

added directly to the pumped sea-water intake.

CONCLUSION

The analytical data has also been assessed for several factors that will show whether the

drinking water is likely to have either corrosive or precipitating factors. These factors are

shown in Table 6.

Generally, these mathematical factors are an indication of the nature of the desalination

water. The CCPP is a negative factor, and indicates that the water is actually aggressive in

nature, and would be expected to dissolve 10.64 mg/l of calcium carbonate with which it is

in contact with.

The CCPP is a calculated figure that uses the following data to yield the expected result. The

data used includes: pH value, total alkalinity mg/l as CaCO3, calcium as calcium hardness

mg/l, temperature in oC, electrical conductivity as µS/cm, and total dissolved solids, TDS as

mg/l.


211

Table 6. Mathematical Factors for Produced Drinking Water

Parameter Math. Result Description of water

CCPP mg/l as CaCO3 -10.64 Aggressive (dissolves) limestone

Langelier Index -1.79 Aggressive water

Ryznar Index 10.22 Corrosive water

DFI - driving force Index 0.02 Corrosive (aggressive to limestone, ie: will dissolve)

Calculated CO2 mg/l 20.3 High carbon dioxide content

Equilibrium Alkalinity 173.0 Expected total alkalinity

Ionic Strength 0.0030

Chloride corrosion Ind. 3.15 Uncertain

Alkali Hazard 0.36 Water suitable for irrigation

Aggressivity Index 9.9 Highly aggressive water

Magnesium Hazard 41.1 Acceptable Mg Hazard

Larson-Skold Index 1.19 Chloride and Sulphate may make it difficult to produce limestone coating in pipework

Equilibrium pHs 8.43 Drinking water pH value is too low at 6.64.

Note: CCPP = calcium carbonate precipitation potential (+/- mg/l as CaCO3).

REFERENCES

[1] A. Abufayed A. and A. ELkebir , 2010. status of water supply and sanitation in

Libya: situation analysis and UNDP interventions, 1, , (1 – 55) .

[2] M. Elabbar and F. Elmabrouk , Desalination, 2005, 185, (31 – 44).

[3] J. Frederick , MEM Master thesis, Desalination, 2010, (1 – 66 ).

[4] H. Krishna , Texas Water Development Board, 2003 (1 - 7).

[5] Using Desalination Technology for water treatment, OTA – B P- O 46,

(Washington, DC, US Government printing office, March 1988, ( 1 - 66).

[6] H. Ettouney and A. Cipollina, Sea Water Desalination, Green Energy and

Technology, DOI 10, 1007 / 978 – 3 – 642 – 01150 – 4 – 2, Springer verlag

Berlin Heidelberg, 2009 (17 – 40).

[7] W. Heinzl et al., Desalination and water treatment 2012, 42, (177- 180).

Documents

WATER CHEMICAL ANALYSIS FOR DIFFERENT …uob.edu.ly/assets/uploads/pagedownloads/05f68-tobruk... · · 2016-11-10chemical analysis was carried out for pH value, electrical conductivity