Uranium and Potentially Toxic Metals During the Mining, Beneficiation, and Processing of Phosphorite...

TECHNICAL ARTICLE

Uranium and Potentially Toxic Metals During the Mining,Beneficiation, and Processing of Phosphorite and their Effectson Ground Water in Jordan

Abdulkader M. Abed Æ Rushdi Sadaqah ÆMustafa Al Kuisi

Received: 17 December 2007 / Accepted: 20 March 2008 / Published online: 19 April 2008

� Springer-Verlag 2008

Abstract Representative samples were collected from

various stages of phosphorite mining and beneficiation

from the Al-Abiad and Al-Hasa mines in central Jordan

and the Eshidiyya mine in southern Jordan. After open pit

mining, the rock is crushed and dry-sieved to pass 12 mm

in order to concentrate the ore. The sieved material is then

agitated, washed with fresh water, and wet sieved to pass

4 mm. Samples were analyzed by ICP-MS for major ele-

ments and As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se, U, V,

and Zn. We found that throughout the above-mentioned

processes, potentially toxic metals are partially removed

from the ore. However, most of the contaminants are still

retained within the final phosphorite product. The slime

and slime water were analyzed; we found no effect of the

slime water on the nearby ground water regime. The

phosphorite is converted to fertilizer through reactions with

sulfuric acid and then ammonia to produce diammonium

phosphate (DAP). Gypsum is produced as a reject. The

potentially toxic metals follow the behavior of P and are

enriched by a factor of more than 1.5 in the DAP compared

with the input phosphorite. The trace metal content in the

phosphogypsum is very low.

Keywords Fertilizers � Field cells � Ground water �Jordan � Phosphorite � Toxic metals � Uranium

Introduction

Jordan started sedimentary phosphate mining in 1933 and

is now one of the world’s leaders, producing more than

6 9 106 metric tons (t) from its Upper Cretaceous phos-

phate deposits. Production now comes from three main

localities: Al-Abiad and Al-Hasa in central Jordan, and

Eshidiyya in the south (Fig. 1). The Ruseifa mines, situated

nearby the capital Amman, were closed in the late 1980s

due to exhaustion as well as to environmental issues related

to mining in a densely populated area.

The Jordanian phosphorites are near-surface deposits,

less than 40 m deep, and are mined by the open pit method.

Although the P2O5 exceeds 30% in most beds, the deposits

are upgraded by simple techniques. The mined material is

first crushed and sieved to pass 12 mm. They are then

agitated, washed with fresh water, and wet sieved. The final

product is less than 4 mm while the 4–12 mm fraction is

rejected. The very fine material is carried out with washing

water as slime and drained into nearby wadis. A small part

of the Eshidiyya phosphorite is floated to get rid of detrital

quartz.

The only environmental problem in the upgrading pro-

cess is the release of the wash water to the nearby

environment. Thus, the concentration of the trace metals in

the slime and slime water is of concern. The Al-Hasa and

Al-Abiad mines have been working since 1962 and 1979,

respectively. A major reason for this study was to deter-

mine whether these operations have elevated trace metal

concentrations in the local ground water.

The geochemistry of the Jordanian phosphorites has

been previously addressed by several workers (e.g., Abed

and Fakhouri 1996; Reeves and Saadi 1971; Sadaqah

2001). Generally, the elements are distributed between

three mineralogical phases: the francolite or carbonate

A. M. Abed (&) � R. Sadaqah � M. A. Kuisi

Department of Applied and Environmental Geology,

University of Jordan, Amman 11942, Jordan

e-mail: [email protected]

123

Mine Water Environ (2008) 27:171–182

DOI 10.1007/s10230-008-0039-3

fluorapatite; the detrital clay mineral phase; or the car-

bonate phase.

More than 90% of the produced phosphorite goes to the

fertilizer industry and consequently to the environment.

Phosphorites, worldwide, are commonly enriched in U and

other metals compared with shales, carbonates, and sand-

stones (e.g., Altschuler 1980; McArthur et al. 1987;

Sadaqah et al. 2005; Slansky 1986). This is due to pref-

erential substitution within the francolite structure (e.g.,

McClellan and Van Kauwenbergh 1990). Uranium in Jor-

danian phosphorites was studied by Abed and Khaled

(1985); Coppes et al. (1977); Khaled and Abed (1982); and

Sadaqah (2001). The trace metals Cd, Mo, U, and Zn are

usually associated with the francolite phase (e.g., Al-Agha

1985; Altschuler 1980; Khaled 1980; Lucas et al. 1980),

whereas the partial adsorption of these and some other

trace metals like Cu, Co, Cr, Ni, and V are associated with

the detrital clay (Abed and Fakhouri 1996; Reeves and

Saadi 1971). The overall aim of this study was to determine

the fate of these metals though mining and processing,

including, as mentioned above, potential ground water

contamination by slime water.

Geological Setting

Phosphorites are widespread in Jordan as part of the Al-

Hasa Phosphorite Formation (AHP). Proven reserves are in

excess of 1.5 billion tons. The AHP forms a belt extending

from the NW corner of Jordan to its SE (Fig. 1). The

phosphorites of Jordan are part of the Upper Cretaceous—

Eocene Tethys phosphorite belt, extending from the

Caribbean to Iran through North Africa and the Eastern

Mediterranean (Abed 1994; Follmi 1996; Notholt et al.

Fig. 1 Location map of the

central Jordan mines (Al-Abiad

and Al-Hisa), Eshidiyya area,

and other phosphorite deposits

in Jordan. The detailed inset

shows the location of the water

sample in central Jordan

172 Mine Water Environ (2008) 27:171–182

123

1989; Sheldon 1987). The age of the AHP is lower Ma-

astrichtian of the Upper Cretaceous (Cappetta et al. 1996;

Hamam 1977; Quennell 1951).

The AHP in central Jordan (Al-Abiad and Al-Hasa)

consists, beside the phosphorite horizon, of various types

of limestones, marl, chert, and porcellanite (Fig. 2a). The

economic phosphorite horizon throughout central Jordan

is friable or slightly cemented with calcite. It consists of

sand-size phosphate particles; pellets, intraclasts and

vertebrate bones, teeth, and coprolites (Abed and Sadaqah

1998; Follmi 1996; Riggs 1979). Detrital quartz is almost

absent. The barren materials associated with phosphate

particles are mainly marl and clay. Therefore, the

phosphorite is subjected to treatment by crushing, wash-

ing, and desliming. For details on the genesis of the

central Jordan phosphorites, see Abed and Sadaqah

(1998).

The AHP in the Eshidiyya in the SE is slightly different

from that in central Jordan due to its proximity to the

Nubian sandstone facies further south. Detrital quartz

prevails at the base of the formation and decreases

upwards. The total thickness of the AHP is 10–15 m. Four

phosphate beds are present, designated from bottom to top

as A3, A2, A1, and A0, separated by non-phosphate

material such as marl, porcellanite, chert, and limestone

(Fig. 2b). The A0 and A2 consist of high-grade, calcareous

Fig. 2 Lithological columnar sections. a Generalized section of central Jordan phosphorites, for legend see (b). b Columnar section of the

Eshidiyya phosphorites

Mine Water Environ (2008) 27:171–182 173

123

phosphorites, the A3 is sandy, and the A1 is rather variable

in composition. For details on the formation of the Es-

hidiyya phosphorites, see Abed et al. (2007).

Methodology

Thirty nine representative samples were collected from all

stages of production from:

• Al-Abiad, Ab series, eight samples: four solids, slime,

slime water, and two ground water samples.

• Al-Hasa, Ha series, eight samples: four solids, slime,

slime water, and three ground water samples.

• Eshidiyya, Sh series, 16 samples: 14 solids, a slime

sample, and slime water sample.

• Fertilizers, seven samples: three from the Indo-Jorda-

nian Company in Eshidiyya and four from the Aqaba

fertilizer complex.

Sampling was carried out in central Jordan between July 26

and August 2, 2006. The Eshidiyya and Aqaba samples

were collected September 12–13, 2006. Around 10 million

(m3per year) of fresh water are used to wash the final

product, becoming slime water. However, this water is

partially recycled.

There were five ground water samples, two from Al-

Abiad mines area, two from Al-Hasa mines area, and one

spring sample from Al-Hasa downstream area. No ground

water samples were collected from Eshidiyya because the

nearest water wells in the B2-A7 aquifers are too far north

([10 km) from the slime water disposal area. The Disi

sandstone aquifer (of Ordovician age) is too deep in the

desliming area and no boreholes are drilled there. For

details of sampling, see Appendix 1.

About 500 g of each solid sample was ground with a

Teema Mill to pass 200 mesh. For slime water and spring

water, a litre sample was collected, and allowed to settle

for several days; a portion of the clear water was taken for

analysis. The powder and the water samples were sent to

the Canadian ACME analytical laboratories where they

were analyzed using ICP and X-ray fluorescence tech-

niques. Seven water samples were analyzed for their

fluorine contents in the Water Research Centre at the

University of Jordan.

Results and Discussion

The chemical analysis for the samples of central Jordan,

Eshidiyya, and the fertilizer industry are displayed in

Tables 1 and 2. The samples of Al-Abiad and Al-Hasa

mines (central Jordan) were put together because they are

geologically one continuous area.

Central Jordan

Alumina (Al2O3), a component of the detrital phase, is

enriched by a factor of three in the slime (column Absl.2

slime) compared to the raw phosphorite (Ab.1 Raw), as

shown in Table 1. This is almost the same for the Al-Hasa

samples. In fact, all of the detrital elements are enriched by

roughly a factor of three at both Al-Abiad and Al-Hasa

mines. Figure 3 shows that most trace metals are also

enriched in the slime by varying degrees, but always by less

than a factor of two. Also, there is a highly significant

positive correlation between most trace metals and alumina.

Despite this, the authors agree with published literature,

which indicate that the trace metals are not fully associated

with the clay minerals and that much is still present within

the apatite (francolite) structure (Altschuler 1980).

The XRD analysis showed that a significant amount of

phosphorite is present in the slime. This is confirmed by the

presence of 17.39 and 20.45% P2O5 in the Al-Abiad and

Al-Hasa mines slime samples, respectively, which is

equivalent to about 50% francolite, as calculated from its

chemical formula. Furthermore, the final product (samples

Ab3 and Ha3) still retains 40–100% of the original con-

centration of the elements enriched in the slime.

The trace metals can be divided into three groups

according to their behavior through the upgrading process:

Group 1: elements that are enriched in the slime,

specifically, Cd, Cu, Pb, Se, and Th, which are enriched

by a factor of about 1.5; Hg and Zn, which are enriched a

factor of about 2; and Cr, V, and Ni, which are enriched

by a factor of more than 2.5, behaving very much like

the detrital material.

Group 2: elements that are practically unchanged: As,

Mo, and Co.

Group 3: elements that are depleted in the slime relative

to the original phosphorite samples: Sr and U. These two

elements are known to be accommodated in the apatite

structure.

The net result is that the beneficiation process produces a

final product that has lower metal concentrations than the

original phosphorite and slime that is enriched in some

metals, where potential toxicity is a concern. Tables 1 and

2 show the composition of the slime water and ground

water in addition to the total dissolved solids (TDS) in the

Al-Abiad and Al-Hasa samples. The concentration of all

elements is in ppb except Cl and TDS, which are in ppm.

The slime water in both mines has higher concentrations of

almost all elements, while the concentrations are less in the

water from the wells representing the ground water regime.

Figure 3c shows this relationship for selected elements. It

should be mentioned that the TDS must be higher than

reported in Table 3, because CO3, HCO3, SO4, and NO3


123

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123

were not analyzed. However, this was not among the aims

of this study.

The concentrations of the potentially toxic metals,

including U, is actually very low in the slime water, on the

order of 10-4–10-5 of their concentration in the raw

phosphorites. The very low concentrations of the trace

metals in the slime indicate that these elements are not

readily dissolved in fresh water, and are either strongly

held in the apatite structure (substituting for Ca like U, Cd,

Sr, Zn, …etc.) or strongly adsorbed on the clay minerals,

like Cr, Ni, ...etc. They are still much lower (3–4 fold) in

the ground water regime, presumably due to adsorption of

these elements on the clays of the soil and stream sediment

and dilution. Thus, the phosphorite mining and upgrading

activities in central Jordan do not appear to be adversely

affecting the region’s ground water; it can be freely used

for domestic purposes as its trace metal content is well

below the Jordanian domestic water standards. It should be

mentioned though that Ra and Ra isotopes were not ana-

lyzed in this work.

Eshidiyya Area

Table 2 shows the chemical analysis of selected samples

from the Eshidiyya area in southern Jordan. The phos-

phorite deposits in the Eshidiyya area are more complex

than those of central Jordan. As previously mentioned, the

deposits in central Jordan consist of one phosphorite

horizon varying in thickness but essentially of rather a

similar composition; i.e. calcareous phosphorites. In Es-

hidiyya, there are four phosphorite horizons separated by

non-phosphorite materials. The A2 and A0 strata are

Table 2 Chemical analysis of the samples from Eshidiyya mine in southern Jordan; major elements are in %, other metals are in ppm or ppb (in

the slime water and ground water)

Sh A1-1 Sh A1-2 Sh A1-3 Sh A1-4 Sh A3-1 Sh A3-2 Sh A3-3 Sh A3-4 Sh A3-5 Sh A3-6 Sh A3-7 Sh A3-8

% ppb

SiO2 22.23 22.21 40.59 14.37 33.73 27.8 39.43 2.18 59.8 17.65 48.01 Si 28,707

Al2O3 1.56 1.86 1.03 1.02 0.67 0.62 0.27 0.11 0.09 0.34 0.2 Al 3

Fe2O3 0.72 0.79 0.43 0.48 0.4 1.02 1.1 0.54 0.33 0.96 0.31 Fe \10

MgO 0.57 0.65 0.42 0.41 0.3 0.2 0.1 0.11 0.06 0.12 0.11 Mg 54,970

CaO 40.84 40.58 30.84 46.35 36.28 38.95 32.46 54.52 22.39 45.85 28.8 Ca 71,216

Na2O 0.28 0.29 0.21 0.31 0.33 0.26 0.19 0.33 0.12 0.26 0.18 Na 208,175

K2O 0.07 0.08 0.06 0.05 0.04 0.04 0.04 0.04 0.04 0.04 0.04 K 7,929

TiO2 0.08 0.1 0.05 0.05 0.04 0.03 0.01 0.01 0.02 0.02 0.02 Ti \10

P2O5 23 24.49 17.47 29.13 23.94 26.42 22.32 36.93 15.12 30.73 19.25 P 133

MnO 0.03 0.03 0.03 0.08 0.07 0.08 0.12 0.06 0.03 0.07 0.04 Mn 465.55

LOI 10.4 8.7 8.7 7.5 4 4.4 3.8 5 1.9 3.8 2.9

TOT/C 2.2 1.52 1.83 1.59 0.7 0.79 0.73 1.25 0.39 0.73 0.59

TOT/S 0.16 0.18 0.13 0.24 0.25 0.24 0.21 0.3 0.12 0.25 0.15

ppm ppb

As 7 8 6 11 11 11 14 25 9 17 11 As 12.1

Cd 18 8 10 10 9 7 9 15 6 11 8 Cd \0.05

Co 1.4 2.1 1.2 1.6 1.1 1.5 1.8 0.9 0.6 1.6 0.6 Co \0.02

Cr 99 86 59 53 59 46 32 32 20 32 32 Cr 16.3

Cu 10 11 7 9 11 8 7 6 3 8 5 Cu 0.7

Mo 1.7 1.8 1.4 1.5 1.5 1.3 1.2 1.5 0.6 1.3 0.9 Mo 4.5

Ni 19 17 27 12 23 13 12 7 19 13 19 Ni 0.9

Hg 0.01 0.01 0.1 0.01 0.01 0.01 0.01 0.02 0.1 0.01 0.01 Hg 0.1

Pb 2.2 2.2 1.3 1.7 1.4 1.2 1.1 1.1 0.8 1.5 1.1 Pb \0.1

Se 0.5 0.6 0.5 0.9 0.5 0.7 0.5 0.8 0.5 0.6 0.5 Se 2.4

Sr 834 907 699 1,113 566 562 420 737 289 539 536 Sr 1,377.55

Th 1 1.1 0.8 1 0.5 0.4 0.3 0.7 0.5 0.5 0.9 Th \0.05

U 34 38 27 44 34 37 32 57 24 46 32 U 6.13

V 65 72 58 56 50 67 65 56 28 66 36 V 3.8

Zn 116 117 98 98 105 80 74 97 42 93 63 Zn 33.6

Cl ppm 278


123

similar to the deposits of central Jordan in that they are

calcareous and high grade. These two beds are sieved only

to select the right size and to slightly upgrade the final

product. The A3 and to some extent A1 have a high content

(Table 3) of silica sand or detrital quartz. Table 2 shows

that detrital quartz reaches more than 30%. Consequently, a

different method of upgrading, flotation is applied. The

relatively high levels of detrital sand in the Eshidiyya

deposits are explained by its proximity to the shorelines of

the southern Tethys continental shelf (Abed et al. 2007;

Bender 1974; Powell 1989).

Most of the analyzed metals are less abundant in

Eshidiyya compared with the central Jordan phosphorite

(Al-Hwaiti et al. 2005). Simple calculations show that the

As, Cr, Cu, Pb, Se, U, V, and Zn would all approach their

concentrations in the deposits of central Jordan, based on

the same percent of silica; i.e., after the removal of the

dilution by silica sand.

Uranium in the A0 horizon is 175 ppm, which is about

twice that of central Jordan and five times the U content in

A1 and A3. The A0 is at or only few metres below the

ground surface in Eshidiyya. Meteoric water diagenesis,

including partial dissolution, may be responsible for the

higher concentration of U in the A0 horizon and the

adsorption on fine materials, mainly clay. Abed and Ab-

dalla (1999) have previously addressed this aspect. Again,

Ra was not analyzed in this work.

Figure 4a and b shows the behavior of some of the

discussed elements during the upgrading of both A1 and

A3. It is clear from the figure as well as from Table 2 that

the slime is much lower in trace metals than the raw

phosphorite. The metal concentrations in the slime and

Fig. 3 Potentially toxic metals behavior through the upgrading

process in central Jordan: a elements associated with clay minerals,

b elements associated with apatite, and c in nearby ground water

Table 3 Average composition of the raw phosphorite samples

C. Jord A0 Sh A1-1 Sh A2-1 Sh A3-1

%

SiO2 10.05 4.29 22.23 9.13 33.73

Al2O3 0.67 0.46 1.56 0.26 0.67

Fe2O3 0.435 0.24 0.72 0.15 0.4

MgO 0.3 0.34 0.57 0.18 0.3

CaO 48.5 52.24 40.84 50.55 36.28

Na2O 0.58 0.43 0.28 0.53 0.33

K2O 0.06 0.06 0.07 0.04 0.04

TiO2 0.035 0.04 0.08 0.02 0.04

P2O5 29.8 27.32 23 33.01 23.94

MnO 0.01 0.01 0.03 0.04 0.07

LOI 9.25 14.35 10.4 5.9 4

Tot/C 2.03 3.39 2.2 1.14 0.7

Tot/S 0.46 0.22 0.16 0.44 0.25

ppm

As 13 15 7 20 11

Cd 5.5 35 18 5 9

Co 0.6 0.7 1.4 0.5 1.1

Cr 144.5 138.5 99 59 59

Cu 12.5 15.5 10 10 11

Hg 0.015 1.15 1.7 1 1.5

Mo 15 27.5 19 7 23

Ni 9 0.06 0.01 0.01 0.01

Pb 3 3 2.2 1.1 1.4

Se 1 0.7 0.5 0.8 0.5

Sr 1,767.5 1,263 834 1,052 566

Th 3.3 1.05 1 0.5 0.5

U 65.5 175 34 46 34

V 87 188 65 55 50

Zn 154.5 159.5 116 93 105


123

slime water are also much lower than observed in central

Jordan. Thus, as we concluded for the deposits of central

Jordan, the slime water appears to pose no environmental

hazard to the ground water. This last conclusion is also

supported by the remoteness of the ground water field

([10 km to the north), and the presence of more than

1,000 m of shale, siltstone, and sandstone of the Paleozoic

Khreim Group separating the slime water disposal site

from the Disi Aquifer below.

The Fertilizers

Phosphorites from central Jordan and/or Eshidiyya are

transported to Aqaba, where the phosphorites are blended

to obtain the composition shown in Table 4. The blended

material is reacted with concentrated sulfuric acid to pro-

duce phosphoric acid (H3PO4) and the reject gypsum

known as phosphogypsum. Phosphoric acid is then reacted

with ammonia to produce the fertilizer, diammonium

phosphate H(NH4)2PO4 or (DAP). Production of DAP

exceeds 1 9 106 t annually.

Columns 1 and 2 in Table 4 show that the P2O5

increased (was concentrated) from 30.76 to 47.79% (by a

factor of about 1.5) when the input phosphorite was

transformed into DAP. Most of the analyzed contaminants

followed the same trend (as shown in Fig. 5 for some of the

elements). This aligns with the chemical analysis of the

gypsum (column 3 in Table 4). P2O5% in the gypsum is

1.41, meaning that 4.5% of the P2O5% is lost with the

gypsum while around 95% of it is incorporated in the DAP.

The gypsum contains relatively low concentrations of

P2O5, U, and trace metals compared with the original

phosphorite (Fig. 5). This means that using the gypsum in

cement production is safe since the contaminants will be

diluted by an additional factor of 20 by the other cement

components, thus reducing the contaminant levels to those

of other building stones or aggregate materials. For

example, U has a concentration of 2.5 ppm in the gypsum

and 0.125 ppm in the final cement product, while the U

content in average shales, sandstones, and carbonates is

3.7, 0.45, and 2.2 ppm, respectively (Krauskopf 1967).

However, the phosphogypsum cannot be considered safe

without knowing its content of Ra. The latter element is the

parent of radon, which decays into five radioactive isotopes

responsible for lung cancer.

Environmental Impact on Ground Water Resources

Five ground water samples were collected from a shallow

aquifer (Wadi Es Sir-Amman Formations, Turonian-Se-

nonian) and analyzed for their chemical constituents. The

analytical results varied widely and are believed to be

related to leaching that is occurring in the unsaturated zone.

Generally, the concentrations were very low, below the

permissible limits from the Jordanian Institute of Standards

and Metrology (JISM) (2001) guidelines for drinking

water. Table 5 shows the concentration of some of the

metals in five ground water samples, compared to the JISM

guidelines. The relatively low concentrations of contami-

nants may be due to the fact that the soil profile serves as

an efficient purifying filter through adsorption onto clay

and the soil’s organic matter content.

On the other hand, F was analyzed in seven water

samples (two slime water and five ground water samples)

in central Jordan (Table 1). The contents of F varied widely

from 7.9 ppm in borehole 11 at Al-Hasa to 0.78 ppm in the

spring water downstream Al-Hasa mines (inset Fig. 1).

Borehole 11 and the Al-Hasa slime water are both higher

than the World Health Organization (WHO) guidelines of

1.5 ppm for F. The rest of the samples are either at this

level or below it (Table 1). Interestingly, the slime water at

Al-Hasa (2.9 ppm) is much lower than borehole 11

(7.9 ppm). Thus, it seems valid to say that the borehole 11

reflects the local conditions of the aquifer. The source of F

is the phosphorite horizon where F ranges between 2 and

4.5% (Abed and Fakhouri 1996).Fig. 4 Potentially toxic metals behavior through the upgrading

process in: a the A1 horizon in Eshidiyya, and b the A3 horizon


123

Conclusions

1. During the upgrading of the phosphorites, most of the

more toxic components are retained with the final

phosphate product.

2. Slime and slime water are not having an adverse effect

on the nearby ground water in central Jordan and

Eshidiyya. Radium content should be measured to

ensure that the slime water is safe.

3. Potentially toxic metals in the fertilizer industry

behave like P and are enriched by a factor of more

than 1.5 in the DAP relative to the input phosphorite.

The uptake of the relatively high levels of potentially

toxic metals in the DAP by soils or plants requires

further research.

Fig. 5 A histogram showing the behavior of the potentially toxic

metals in the fertilizers industry at Aqaba from the input phosphorite,

DAP and phosphogypsum

Table 4 Chemical analysis of

the samples from the fertilizer

industry in Aqaba

Aqaba 1 Aqaba 3 Aqaba 4 % Aqaba2

Input phosphrite DAP Phospho-gupsum Phosphoric acid

%

SiO2 9.51 1.48 7.59 Si \0.004

Al2O3 0.64 0.95 0.07 Al 0.4

Fe2O3 0.44 0.59 0.04 Fe 1.06

MgO 0.29 0.46 0.01 Mg 0.65

CaO 49.07 1.16 33.55 Ca 0.016

Na2O 0.5 0.26 0.15 Na 0.068

K2O 0.04 0.08 0.04 K 0.02

TiO2 0.03 0.01 0.02 Ti 0.11

P2O5 30.76 47.79 1.41 P 10

MnO 0.01 0.02 0.01 Mn 0.16

LOI 8.4 – 16.3

Tot/C 2.17 2.14 0.11

Tot/S 0.54 1.45 16.94 0.86

SUM 99.71 52.84 59.13

ppm

As 12 11.6 0.5 27.6

Cd 8.6 10.4 1.8 21.6

Co 0.5 1.3 \0.5 4.8

Cr 138 199 77 188

Cu 12.2 17.5 0.7 33.8

Hg \0.01 \0.01 0.01 \0.01

Mo 6.7 7.1 0.4 5.3

Ni 16.6 23.6 1.1 53.7

Pb 2.6 0.9 1.5 \0.01

Se 1.6 \0.5 0.7 \0.5

Sr 1,569.6 139.1 906.5 0.06

Th 2.4 2.8 0.5 0.31

U 65 106.7 2.3 187.2

V 80 127 \5 245.6

Zn 162 281 5 438.1

Br \0.5

Cl 1,636


123

4. The phosphogypsum has very low levels of potentially

toxic components and can be used in the cement

industry without harming the environment. To fully

justify this conclusion, radium must be analyzed.

Acknowledgments We thank the three mine managers, Eng. Zuhair

Rabba (Al-Abiad), Eng. Jihad Hjazin (Al-Hasa), and Eng. Mamdoh

Al-Jazi (Eshidiyya) for their cooperation and Dr. Pier Pufahl from

Acadia University, Canada, for facilitating the analysis of the sam-

ples. This work was partially supported by the Deanship of Scientific

Research at the University of Jordan.

Appendix 1

Eight samples were collected from Al-Abiad mines

(Ab series):

Ab1: raw phosphate represents a blinding from three

working ore bodies: 3, 8, and 33.

Ab2: is a screened sample of Ab1 less than 12 mm.

Ab3: final product less than 4 mm.

Ab4: a reject between 4 and 12 mm.

Ab.Sl.2: deslimed fine material \4 lm.

Ab.Sl.1: slime water.

Ab.BH1 and Ab.BH5: ground water from boreholes one

and five, located in the area.

Eight samples were collected from Al-Hasa mines

(Ha series):

Ha1: a raw phosphate sample, represents a blending

from working ore bodies 2 and 13 south.

Ha2: is a screened sample of Ha1 less than 12 mm.

Ha3: final product less than 4 mm.

Ha4: a reject between 4 and 12 mm.

Ha.Sl.2: deslimed fine material \4 lm.

Ha.Sl.1: slime water.

Ha. BH11: ground water from borehole 11.

Ha.Ag1: ground water from a borehole of agriculture

station that belongs to the ministry of agriculture; both

Ha. BH11 and Ha.Ag1 are located few hundred meters

from the slime draining system.

Ha.Sp1: ground water from a spring about 4 km down-

gradient of the wadi where the slime is drained. The

spring drains from a shallow Turonian to the Maastrich-

tian aquifer.

Sixteen samples were collected from the Eshidiyya

mines (Sh series):

Sh.A0.1: a raw phosphate sample from the lower part of

the A0 horizon.

Sh.A0.2: a raw phosphate sample from the upper part of

the A0 horizon.

Sh.A1.1: a raw phosphate sample from A1 horizon.

Sh.A1.2: a screened sample of Sh.A1.1 less than

12.5 mm.

Sh.A1.3: screened between 1 and 12.5 mm.

Sh.A1.4: final product less than 1 mm.

Sh.A2.1: a raw phosphate sample from A2 horizon.

Sh.A2.2: screened less than 4 mm.

Sh.A3.1: raw phosphate sample from A3.

Sh.A3.2: screened less than 12.5 mm.

Sh.A3.3: screened between 5 and 12.5 mm.

Sh.A3.4: less than 5 mm after flotation (final product).

Sh.A3.5: floated silica less than 5 mm. (reject).

Sh.A3.6: subcommertial product between -5 mm and

+2 mm after flotation.

Sh.A3.7: fine, clay size phosphate deslimed from A1 and

A3.

Sh.A3.8: deslimed water.

Table 5 Concentration (ppb) of

contaminants in ground water

from the shallow aquifer in

central Jordan compared with

the Jordanian Standards (286/

2001) for drinking water (JISM

2001)

Parameters Maximum permissible

limit

Ab.Bh1 Ab.Bh

5

Ha.Bh11 Ha.Ag.

1

Ha.Sp1

Al 100 18 2 19 6 49

Mn 100 \0.05 \0.05 \0.5 \0.05 \0.5

Fe 300 \10 \10 \10 \10 \10

Cu 1,000 0.5 0.6 0.5 0.6 0.3

Zn 3,000 \0.5 \0.5 \0.5 215 2.3

As 10 0.7 2.8 0.5 4.1 1

Pb 10 \1 \1 \0.1 2.4 0.2

Cd 3 \0.05 \0.05 \0.05 \0.05 \0.05

Cr 50 10.5 9.1 12.7 17.7 20.4

Se 50 20.5 121.2 1.9 28.7 5.3

Hg 2 \0.1 \0.1 \0.1 \0.1

Ni 70 1.4 20.7 \0.2 7.5 0.3

V 100 12 60 1.1 23 16.2


123

Three samples were collected from the Indo-Jordan

Chemical company, where phosphoric acid is produced

for export to India:

Indo-Jo1: phosphoric acid.

Indo-Jo2: raw input phosphate.

Indo-Jo3: phosphogypsum.

Four samples were collected from the fertilizer complex

at Aqaba:

Aqaba 1: raw phosphate input.

Aqaba 2: phosphoric acid.

Aqaba 3: diammonium phosphate.

Aqaba 4: phosphogypsum.

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