Comparison between the irrigation qualities of conventional tertiary and UF + RO advancedtreated wastewaters

doi:10.4236/as.2011.24068

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Vol.2, No.4, 526-532 (2011)

doi:10.4236/as.2011.24068

Agricultural Scienc es

Comparison between the irrigation qualities of

conventional tertiary and UF + RO advanced

treated wastewaters

Abdallah Abusam1*, Bader Al-Anzi2

1Water Resource Division, Water Technologies Department, Kuwait Institute for Scientific Research, Safat, Kuwait;

*Corresponding Author: abusam3a@yahoo.com

2Environmental Technology Department and Management, College for Women, Kuwait University, Safat, Kuwait.

Received 9 September 2011; revised 18 October 2011; accepted 28 October 2011.

ABSTRACT

The Ultrafiltration and Reverse Osmosis (UF +

RO) membrane system is nowadays frequently

used in wastewater reclamation. The almost

complete removal of the dissolved elements,

however, raises concerns about the suitability

of the water treated by this system for agricul-

tural irrigation. This study compared the irriga-

tion qualities of UF + RO permeate and conven-

tional tertiary effluent, using the WHO guide-

lines. Obtained results indicated slight to mod-

erate degrees of restrictions are required for the

reuse of the tertiary effluent as agricultural irri-

gation water, while no restrictions are needed

for the UF + RO permeate. But it had also been

found that the UF + RO system unnecessarily

deprive the reclaimed water from nutrients and

organic matters, which would have been recy-

cled benefic ially through agricultural irrigation.

Keywords: Wastewater; Reclamation; Reuse;

Tertiary Effluent; UF + RO Permeate

1. INTRODUCTION

Water scarcity is the main reason for the increasing

trend in wastewater reuse in agriculture worldwide. Es-

pecially in arid and semi arid regions, where water re-

sources are very limited, wastewater reuse has become

the most attractive option to alleviate pressure on fresh-

water resources. Wastewater reuse has generally proven

to be economically and environmentally beneficial [1].

Advantages of wastewater reuse include reduction of the

amount of freshwater extracted from the environment,

provision of a reliable supply of large amounts of water,

enhancement of crop productivity and reduction of en-

vironmental degradation [1-3]. However, potential prob-

lems related to wastewater reuse are risks from patho-

genic microorganisms, increased soil salinity due to high

total dissolved solids (TDS) concentrations, clogging of

soils and/or irrigation systems with suspended solids [4],

and introduction of toxics to crops and crop consumers

(trace elements, e.g. Na, B and Se and toxic compounds,

e.g. endocrine disrupters and pharmaceuticals) [5]. There-

fore, a reclaimed wastewater that will be reused as agri-

cultural irrigation water should satisfy certain quality

requirements, e.g. the Food and Agriculture Organiza-

tion (FAO) proposed quality requirements [6].

Wastewater is conventionally treated up to a second-

dary level (i.e., biological treatment plus chlorination) or

to a tertiary level (i.e., biological treatment plus sand

filtration and chlorination). Usually, secondary and terti-

ary treatments result in a limited removal of dissolved

salts and toxic compounds, and therefore, they are com-

monly not considered to meet the requirements for unre-

stricted irrigation. For this reason the use of membrane

systems for advanced treatment of wastewater has re-

cently received great attention [7].

Membrane systems are frequently used in the recla-

mation of wastewater in order to produce high quality

water for e.g. agricultural irrigation, industrial uses and

aquifer recharge applications [8]. Membranes used in

water and wastewater treatment can be classified, based

on the pore size, into four categories: Microfiltration

(MF), Ultrafiltration (UF), Nanofiltration (NF) and Re-

verse Osmosis (RO) membranes [9]. For polishing the

secondary effluent, a two-stage membrane system that

consists of UF + RO membranes is commonly used.

Here the function of the UF is to remove organic matter

and pathogens, while the function of the RO is to re-

move dissolved solids [10]. Due to the very high re-

moval efficiency, however, there are concerns that con-

ventional UF + RO treatment may deprive the reclaimed

water from plant essential nutrients [11]. The objective

A. Abusam et al. / Agricultural Sciences 2 (2011) 526-532

527527

of this study was to compare the irrigation quality of a

tertiary effluent to wastewater treated to advanced level

using UF + RO membrane system.

2. MUNICIPAL WASTEWATER

TREATMENT AND REUSE

IN KUWAIT

Kuwait municipal wastewater is treated to tertiary or

advanced levels at four main activated sludge plants,

located in Jahra, Riqqa, Sulaibiya and Um-Al-Haiman

areas. Sulaibiya plant is the world’s largest membrane-

based reclamation plant, which was originally built for

providing an alternative source to potable water for Ku-

wait [12]. But its effluent is used since commissioning in

December 2004 in agricultural and landscape irrigations.

Sulaibiya plant treats wastewater up to UF and RO ad-

vanced levels. The other three plants (Jahra, Riqqa and

Umm-Al-Haiman plants) are all conventional activated

sludge plants that treat wastewater to tertiary levels

(biological treatment plus sand filtration and chlorine-

tion). Table 1 gives the basic technical information

about the main municipal wastewater treatment plants in

Kuwait.

The effluents of only Jahra (tertiary) and Sulaibiya

(RO permeate) plants are pumped to a central facility,

called the Data Monitoring Center (DMC), located about

30 km from Kuwait city, where treated wastewater is

stored, further chlorinated and distributed to the main

farming areas situated in Abdalli, Sulaibiya and Wafra

areas. Effluents of the other plants are reused mainly on-

site or to irrigate greeneries near the motorways.

The DMC facility has six effluent storage reservoirs

(ESRs) of total capacity equal to 340,000 m3, pump

houses, chlorination units, a laboratory for water analy-

sis and a computerized data management facility for

recording the daily quantity and quality of the ESRs in-

flows and outflows. Storage of treated wastewater efflu-

ents in properly designed and operated ESR’s improves

the effluent quality, particularly with respect to concen-

trations of nutrients and trace metals [13], and thus help

in producing high crop yields [14].

3. MATERIALS AND METHODS

Data used in this study were obtained from the records

of the DMC facility in Kuwait. DMC daily-records con-

tain information about the quantity and quality of in- and

outflow of the ESRs. In this study only the data for the

year 2005 were used. During 2005, the average inflows

from Sulaibiya and Jahra plants were 331,367 m3/d and

25,805 m3/d, respectively. Thus, the average hydraulic

residence time at the ESRs was 25.5 hours, while the

average mixing ratio (Jahra stream/Sulaibiya stream)

was 0.08 (ranged from 0.03 to 0.14).

Collected daily data about the treated wastewater

quantity and quality was summarized and statistically

analyzed. Wastewater quality parameters were actually

determined at the DMC laboratory in accordance with

the American standard methods for water and wastewa-

ter examination [15], except for the EC and pH which

were determined in the field using portable measuring

devices. Solids (TSS, TDS and VSS) were determined

by gravimetric method. COD was determined by stan-

dard open reflux method. BOD5 was found after five

days incubation at 20˚C. Hach spectrophotometers were

used to measure NO4, PO4 and SO4 while NH4 and org-N

were determined by distillation and digestion methods.

Na, Ca and heavy metals were measured using a flame

atomic adsorption spectrophotometer (ASS).

Quality parameters of Jahra tertiary effluent and Su-

laibiya RO permeate were assessed for agricultural irri-

gation and compared, using criteria adopted from the

WHO guidelines [5] given in Ta ble s 2 and 3. The crite-

ria consisted of pH, EC, TDS, TSS, SAR, Cl, Na, Ca,

Mg, B, HCO3 and TN (Tab le 2 ) plus ten trace elements

(Table 3). SAR was calculated as follows:

Ca Mg

SAR





2

(1)

where Na+, Ca2+ and Mg2+ are in meq/l.

Table 1. Kuwait’s municipal wastewater treatment plants.

Plant Secondary Treatment Tertiary Treatment Advanced Treatment

Jahra

(70,000 m3/d)

6 conventional activated-sludge systems operated

in extended aeration mode. Sand filtration + chlorination -

Riqqa

(120,000 m3/d)

12 conventional Activated-sludge systems operated

in extended aeration mode. Sand filtration + chlorination -

Sulaibiya

(420,000 m3/d) 9 BNR activated-sludge systems. - Disc filtration + UF

+ RO + chlorination

Umm-Al-Haiman

(20,000 m3/d) 4 oxidation ditch systems. Sand filtration + UV

+ chlorination -

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528

4. RESULTS AND DIS CUSSION

The measured qualities of Jahra tertiary effluent and

Sulaibiya RO permeate are summarized in Tab le 4. The

following sections discuss the irrigation qualities of the

two steams, based on the criteria presented in Ta bles 2

and 3.

4.1. pH

Irrigation water with low pH (<6.5) promotes leach-

ing of heavy metals, while irrigation with water which

has high pH (>11) destroys bacteria and can also tem-

porarily inhibit movement of heavy metals. The WHO

recommends the pH values of the irrigation water to be

in the range of 6.5 - 8.0. In general, pH outside this rec-

ommended range can cause a nutritional imbalance or

may contain a toxic ion, and thus, negatively affecting

plant growth [6,16]. The measured pH values ranged

from 6.5 - 7.3 (mean = 7.1) and 7.2 - 7.4 (mean = 7.3)

for Jahra tertiary effluent and Sulaibiya RO permeate,

respectively (Ta b l e 4 ). This implies that both Jahra and

Sulaibiya effluents satisfy the WHO recommendation

with respect to pH values.

4.2. Salinity Hazards

In contrast to drinking water (EC < 0.7, TDS < 500

mg/l), treated wastewater is generally characterized by

high salinity due to addition of salts from domestic and

industrial sources. High salinity can damage soil, plants,

crops and groundwater [5]. EC and TDS are good indi-

cators of salinity hazards to crops. Table 4 shows that

EC and TDS concentrations in Jahra tertiary effluent

(EC = 1.7 dS/m, TDS = 932 mg/l), are much higher than

that of Sulaibiya RO permeate (EC = 0.17, TDS = 88.4).

Although EC in the range of 0.75 to 2.25 µS/m (similar

to that of Jahra effluent) is widely used [17], irrigation

with water that has EC closer to 2.0 µS/m can be a long-

term health hazard to animals and humans [18]. Accord-

ing to WHO guidelines (Table 3), slight to moderate

restrictions should be applied when irrigating with Jahra

tertiary effluent, while none is required when irrigating

with Sulaibiya RO permeate. Main restrictions that

should be applied in such a case are selection of salt tol-

erant crops and application of appropriate salinity con-

trol measures.

Table 2. Guidelines for interpretation of water quality for irrigation (Adopted from [5]).

Degree of Restriction

Potential Irrigation Problem Unit None Slight to Moderate Severe

EC µS/m <0.7 0.7 - 3.0 >3.0

TDS mg/l <450 450 - 2000 >2000

TSS mg/l <50 50 - 100 >100

EC at SAR = 0 - 3 dS/m >0.7 0.7 - 0.2 <0.2

EC at SAR = 3 - 6 dS/m >1.2 1.2 - 0.3 <0.3

EC at SAR = 6 - 12 dS/m >1.9 1.9 - 0.5 >0.5

EC at SAR = 12 - 20 dS/m >2.9 2.9 - 1.3 <1.3

EC at SAR = 20 - 40 dS/m >5.0 5.0 - 2.9 <2.9

Sodium (Na+): Sprinkler Irrigation meq/l <3 3 - 9 >9

Chloride (Cl−): Sprinkler Irrigation meq/l <3 >3

Chloride (Cl−): Surface Irrigation meq/l <4 4 - 10 >10

Bicarbonate (HCO3) mg/l <90 90- 500 >500

Boron (B) mg/l <0.7 0.7 - 3.0 >3.0

Total Nitrogen (TN) mg/l <5 5 - 30 >30

pH - Normal range: 6.5 - 8.0

Table 3. WHO recommended maximum concentration for trace elements [6].

Element Recommended Maximum Concentrations (mg/l)

Al 5.0

Cd 0.01

Cr 0.10

Co 0.05

Cu 0.20

Fe 1.0

Pb 5.0

Mn 0.20

Ni 0.20

Zn 2.0

A. Abusam et al. / Agricultural Sciences 2 (2011) 526-532

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Table 4. Measured quality of Jahra tertiary effluent and Sulaibiya RO permeate.

Jahra Tertiary Effluent Sulaibiya RO Permeate

Parameter

Range Mean Range Mean

pH (-) 6.5 - 7.3 7.1 ± 0.3 7.2 - 7.4 7.3 ± 0.1

EC (dS/m) 1.1 - 2.1 1.7 ± 0.4 0.04 - 0.35 0.17 ± 0.13

TDS (mg/l) 70 - 1380 932 ± 437 13 - 209 88.4 ± 77.5

TSS (mg/l) 3 - 10.3 8.0 ± 2.9 0.8 - 3.2 1.9 ± 1.0

SAR (meq/l)1/2 0.9 - 4.7 2.9 ± 1.5 0.2 - 23.3 5.2 ± 0.3

Ca2+ (mg/l) 18.1 - 31.9 23.5 ± 5.1 0 - 2.2 1.0 ± 0.1

Mg2+ (mg/l) 1.7 - 34.2 16.5 ± 3.0 0 - 10.4 10.4 ± 2.8

Na+ (mg/l) 42.6 - 114.4 92.5 ± 29.6 0.6 - 14.4 5.9 ± 0.5

COD (mg/l) 16.3 - 26.6 22.5 ± 3.7 1.3 - 6.3 3.0 ± 0.18

BOD5 (mg/l) 0 - 8.5 5.0 ± 2.6 3 - 6.3 4.7 ± 1.4

Cl− (mg/l) 256 - 824 397.7 ± 191.4 8 - 51 27.9 ± 1.9

B (mg/l) 0.06 - 0.35 0.14 ± 0.01 0.02 - 0.11 0.06 ± 0.01

HCO3 (mg/l) 78 - 139 110.3 ± 23.4 1 - 34 24.5 ± 11.0

TN (mg/l) 4.1 - 9.8 6.0 ± 2.4 0.6 - 5.8 1.8 ± 0.2

PO4 (mg/l) 3.5 - 5.8 5.0 ± 0.9 0.8 - 3.7 1.9 ± 0.1

Al (mg/l) 0.0001 - 0.3357 0.0600 ± 0.1226 0.0001 - 0.2211 0.0983 ± 0.01

Cd (mg/l) 0.0001 - 0.0107 0.0066 ± 0.0033 0.0004 - 0.4880 0.0648 ± 0.02

Cr (mg/l) 0.0001 - 0.1126 0.0200 ± 0.0041 0.0001 - 0.0667 0.0099 ± 0.002

Co (mg/l) 0.0001 - 0.0115 0.0020 ± 0.0003 0.0001 - 0.0476 0.0109 ± 0.002

Cu (mg/l) 0.0001 - 0.0114 0.0066 ± 0.0037 0.0008 - 0.0122 0.0045 ± 0.0004

Fe (mg/l) 0.0006 - 0.0019 0.0012 ± 0.0006 0.0003 - 00013 0.0008 ± 0.0001

Pb (mg/l) 0.0100 - 0.1068 0.0523 ± 0.0369 0.0036 - 0.1063 0.0467 ± 0.0367

Mn (mg/l) 0.0080 - 0.0291 0.0163 ± 0.0079 0.0002 - 0.0054 10.4 ± 0.0015

Ni (mg/l) 0.0001 - 0.0055 0.0025 ± 0.0003 0.0001 - 0.0229 0.0040 ± 0.001

Zn (mg/l) 0.0252 - 0.0677 0.0413 ± 0.0161 0.0023 - 0.0216 0.0138 ± 0.006

4.3. Total Suspended Solids

Suspended solids present in irrigation water can be

organic matters (e.g. plants, algae, bacteria), and/or in-

organic matters (clay, sand, silt). High suspended solids

concentration in irrigation water may cause a number of

problems e.g. clogging of the irrigation systems, sealing

of the soil surface, filling the voids between sand parti-

cles, reducing soil infiltration and drainage capability

and increasing soil compaction. According to the WHO

standards, total suspended solid (TSS) less than 50 mg/l

is safe for a drip irrigation system, while values above

100 mg/l can cause plugging. Table 4 shows that TSS of

Jahra tertiary effluent is in the range of 3 - 10.3 mg/l

(mean = 8), while that of Sulaibiya RO permeate is in

the range of 0.8 - 3.2 mg/l (mean = 1.9). This indicates

that TSS of both the tertiary and RO effluents are satis-

fying the WHO standards.

4.4. Sodium, Calcium and Magnesium

Hazards (SAR)

Sodium content is an important criterion for evaluat-

ing irrigation water quality. Excessive amount of sodium

can lead to development of alkaline soil and cones-

quently to reduction of soil permeability. At high con-

centration, sodium ion can replace the adsorbed calcium

and magnesium ions, leading soil destruction. High con-

centration of sodium can also reduce the plant capability

to absorb nutrient potassium and magnesium [19]. In

addition, high concentrations of sodium may also cause

injury to leaves [20]. The WHO guidelines [6] recom-

mend no restriction at sodium concentration less than 3

meq/l and slight to moderate degree of restriction at so-

dium concentration in the range 3 - 9 meq/l, but severe

restriction at sodium concentration greater than 9 meq/l.

Ta b l e 4 shows that sodium concentration of Jahra terti-

A. Abusam et al. / Agricultural Sciences 2 (2011) 526-532

530

ary effluent and Suliabiya RO permeate varied between

42.6 - 113.4 mg/l (1.85 - 4.93 meq/l) and 0.6 - 14.4 mg/l

(0.03 - 0.63 meq/l), respectively. Therefore, no degree of

restriction is required when irrigating with Suliabiya RO

permeate, while a slight to moderate degree of restriction

is required when irrigating with Jahra tertiary effluent.

Possible future sodium damage to soil is commonly

measured in terms of the Sodium Adsorption Ratio (SAR).

SAR expresses better the exchangeable sodium percent-

ages in the soil than only sodium percentage [21]. As

shown in Table 4, calculated values of SAR were be-

tween 0.9 - 4.7 and 0.2 - 23.3, for Jahra tertiary effluent

and Sulaibiya RO permeate, respectively, when EC val-

ues were in the range 1.1 - 2.1 and 0.04 - 0.35, respec-

tively. According to the WHO guidelines (Table 2), thus,

only a slight to moderate degree of restriction is re-

quired when irrigating with Jahra tertiary effluent, while

none is require when irrigating with Sulaibiya RO per-

meate.

4.5. Chloride

Because it is usually not absorbed by soil and thus it

moves in the transpiration stream and accumulates in the

leaves, high chloride concentrations in the irrigation wa-

ter can cause leaf burning or dying of leaf tissues. As

shown in Table 4, the chloride concentration of Jahra

tertiary effluent was in the range of 256 - 824 mg/l (7.2 -

23.2 meq/l) and that of Suliabiya RO effluent was 8 - 51

mg/l (0.2 - 1.4 meq/l). According to the WHO guidelines

presented in Ta b l e 3 , a slight to moderate degree of re-

striction is therefore required when irrigating with Jahra

tertiary effluent, while no degree of restriction is re-

quired when reusing Sulaibiya RO permeate.

4.6. Boron

Boron is an essential micronutrient for plant growth.

Although boron can affect sensitive crops (e.g. orna-

mental plants), it does not affect soil [5]. Boron concen-

tration in Jahra tertiary effluent varied between 0.06 -

0.35 mg/l (mean = 0.14), while that of Sulaibiya RO

permeate was in the range of 0.02 - 0.11 (mean = 0.06)

(Table 4). As the WHO guidelines [6] do not recom-

mend any restriction for boron concentration less than

0.7 mg/l, therefore, no degree of restriction is required

when irrigating with Jahra tertiary effluent nor with Su-

laibiya RO permeate.

4.7. Total Nitrogen

Nitrogen is an essential macronutrient for plants. It is

usually found in wastewater in the forms of ammonia,

nitrite, nitrate and organic forms of nitrogen. Total ni-

trogen (TN) is the sum of these forms of nitrogen. TN

concentration of the Jahra tertiary effluent was in the

range of 4.1 - 9.8 mg/l (mean = 5.0), while TN concen-

tration of Sulaibiya RO permeate was 0.6 - 5.8 mg/l

(mean = 1.8) (Tabl e 4). Notice that TN of Sulaibiya RO

permeate (mean = 1.8) is much less than that of Jahra

tertiary effluent (mean = 5.0). That is, RO treatment had

unnecessarily deprived the Sulaibiya reclaimed water

from nitrogen, which is an essential plant macronutrient.

According to the WHO guidelines (Tab le 2), no degree

of restriction is required for irrigation with water with

TN less than <5 mg/l, while a slight to moderate degree

of restriction of required for irrigation water with TN

between 5 - 30 mg/l. Generally, TN less than 30 mg/l

does not harm plants, except sensitive crops such as

sugar beets [6]. Therefore, only a slight to moderate de-

gree of restriction is required when irrigating using Jahra

tertiary effluent for irrigation, while none is required

when reusing Sulaibiya RO permeate.

4.8. Heavy Metals

Irrigation with water which contains high concentra-

tions of heavy metals can lead to metal accumulation in

both soils and crops, which consequently will cause

health problems to crop consumers. Heavy metals are

usually not absorbed by plants unless they reach the

threshold concentrations [5]. Comparison of heavy met-

als concentrations given in Tabl e 4 to the WHO recom-

mended maximum levels (Table 3) clearly indicates that

concentrations of heavy metals in Jahra tertiary effluent

are far below the recommended maximum levels. Simi-

larly, heavy metals concentrations in Sulaibiya RO per-

meate are also less than the recommended maximum

level, except few instances of high cadmium concentra-

tion (0.4880 mg/l while the recommended maximum is

0.01). [5]. Usually, common wastewater treatment proc-

esses remove most of heavy metal concentrations [22] as

demonstrated by the results obtained for Jahra tertiary

effluent (Table 4).

4.9. Organic Matter

Organic content of wastewater usually increases soil

moisture, retain metals and enhances microbial activity.

Therefore, irrigation with wastewater is better than add-

ing synthetic fertilizers [6]. Irrigation with even extremely

high organic matter concentration (BOD > 500 mg/l)

usually does not impact negatively the environment.

Table 4 shows that COD of Jahra tertiary effluent was in

the range of 16.3 - 26.6 mg/l (mean = 22.5), while that

of Sulaibiya RO permeate was in the range of 1.3 - 6.3

mg/l (mean = 3.0). Notice also here how unnecessarily

RO treatment had removed almost all the organic matter

content from Sulaibiya wastewater. In contrast, all BOD

A. Abusam et al. / Agricultural Sciences 2 (2011) 526-532

531531

of Jahra tertiary effluent can be reused beneficially in

agriculture and without any adverse environmental im-

pact.

4.10. Phosphorus

Phosphorus is also a plant macronutrient. Normally

wastewater does not contain large amounts of phospho-

rus that can impact negatively the environment. Further,

irrigation with high concentrations of phosphorus and

for a long term does not damage the environment [6].

Table 4 shows that measured PO4 values were in the

range of 3.5 - 5.8 mg/l (mean = 5.0) and 0.8 - 3.7 mg/l

(mean = 1.9) for Jahra tertiary effluent and Sulaibiya RO

permeate, respectively. Also notice here that, RO treat-

ment had without a need removed most of the phospho-

rus, which would have been beneficially recycled through

agricultural irrigation reuse.

5. CONCLUSIONS

Based on the results of this study, the following con-

clusions could be made:

• According to the WHO guidelines [6], no degree of

restriction is required when irrigating with Sulaibiya RO

permeate, while only slight to moderate degrees of re-

strictions are required when irrigating with Jahra tertiary

effluent, with respect to salinity hazards and to high

concentrations of sodium and chloride.

• RO treatment, however, removes unnecessarily ni-

trogen, phosphorus and organic matter from the reclaimed

wastewater.

6. ACKNOWLEDGEMENTS

Data used in this study were collected during the execution of a pro-

ject entitled “Development of Wastewater Quality Database and Assess-

ment of Effluent Quality for Potential Reuse in Kuwait (WT013C)” at

KISR. This project was partially financed by the Kuwait Foundation

for the Advancement of Sciences (KFAS).

REFERENCES

[1] Layson, A. and Sorgini, L. (2007) Low-pressure mem-

branes help solve water scarcity. Water , 34, 34-36.

[2] Sheikh, B., Jaques, R.S. and Cort, R.P. (1987) Reuse of

municipal wastewater effluent for irrigation of raw-eaten

food crops: A five year field study. Desalination, 67,

245-254.

[3] Chakrabarti, C. (1995) Residual effect of long-term land

application of domestic wastewater. Environmental In-

ternational, 21, 333-339.

doi:10.1016/0160-4120(95)00021-C

[4] Toze, S. (2006) Reuse of effluent water: Benefits and

risks. Agricultural Wa ter Management, 80, 146-159.

doi:10.1016/j.agwat.2005.07.010

[5] WHO (2006) Guidelines for the safe use of wastewater,

excreta and grey water. Wastewater Use in Agriculture, 2,

World Health Organization, Lyon.

[6] Ayers, R.S. and Westcot, D.W. (1985) Water quality for

agriculture. FAO Irrigation and Drainage, Paper 29,

Food and Agriculture Organization, Rome.

[7] Oron, G., Gillerman, L., Bick, A., Buriakovsky, N., Ma-

nor, Y., Ben-Yatshak, E., Katz, L. and Hagin, J. (2006) A

two stage membrane treatment of secondary effluent for

unrestricted reuse and sustainable agricultural production.

Desalination, 187, 335-345.

doi:10.1016/j.desal.2005.04.092

[8] Schaefer, J. (2001) Reliable water supply by reusing

wastewater after membrane treatment. Desalination, 138,

91-92. doi:10.1016/S0011-9164(01)00249-1

[9] Frenkel, V.S. (2008) Membrane in water and wastewater

treatment. Proceedings of the World Environmental and

Water Resources Congress, 2008, 316-324.

[10] Oron, G., Gillerman, L., Buriakovsky, N., Bick, A.,

Gargir, M., Dolan, Y., Manor, Y., Katz, L. and Hagin, J.

(2008) Membrane technology for advanced wastewater

reclamation for sustainable agriculture production. De-

salination, 218, 170-180.

doi:10.1016/j.desal.2006.09.033

[11] Abusam, A. and Shahalam, A. (2010) Comparative assess-

ment of advanced membrane treatment of municipal

wastewater for reuse in Kuwait. Desalination and Water

Treatment, 13, 254-258. doi:10.5004/dwt.2010.1096

[12] Gagne, D. (2004) Sulaibiya water reuse project begins

full operations. Water and Wastewater International, 19,

19-21.

[13] Mancini, G., Barone, C., Roccaro, P. and Vagliasindi,

F.G.A. (2007) The beneficial effects of storage on the

quality of wastewater for irrigation: A case study in Sicily.

Water Science and Technology, 55, 417-424.

doi:10.2166/wst.2007.042

[14] Barbagallo, S., Cirelli, G. L., Consoli, S. and Somma, F.

(2003) Wastewater quality improvement through storage:

A case study in Sicily. Water Science and Technology, 47,

169-176.

[15] APHA (1998) Standard methods for examination of wa-

ter and wastewater. 20th Edition, American Public Health

Association, Washington, DC.

[16] Pescod, M.B. (1985) Wastewater treatment and use in

agriculture. Irrigation and Drainage Paper No. 47, FAO,

Rome.

[17] Alobaidy, A.H.M.J., AL-Sameraiy, M.A., Kadhem, A.J.

and Abdul-Majeed, A. (2010) Evaluation of treated mu-

nicipal wastewater quality for irrigation. Journal of En-

vironmental Protection, 1, 216-225.

doi:10.4236/jep.2010.13026

[18] Forth, H.D. (1984) Fundamentals of soils science. 7th

Edition, John Wiley and Sons, New York.

[19] Harussie, Y., Rom, D., Galil, N. and Semiat, R. (2001)

Evaluation of membrane processes to reduce the salinity

of reclaimed wastewater. Desalination, 137, 71-89.

doi:10.1016/S0011-9164(01)00206-5

[20] Begum, S. and Rasul, M.G. (2009) Reuse of stormwater

for watering gardens and plants using green gully—A

new stormwater quality improvement device (SQID).

Water Air Soil Pollution: Focus, 9, 371-380.

doi:10.1007/s11267-009-9226-x

A. Abusam et al. / Agricultural Sciences 2 (2011) 526-532

532

[21] Tiwari, T.N. and Manzoor, A. (1988) Pollution of su-

barnarekha river near Jamshedpur and the suitability of

its water for irrigation. Indian Journal of Environmental

Protection, 8, 494-497.

[22] Shiekh, B., Jaques, R.S. and Cort, R.P. (1987) Reuse of

tertiary municipal wastewater effluent for irrigation of

raw eaten food crops: A 5 year study. Desalination, 67,

245-254.