89

Volume 75

Issue 2

October 2015

Pages 89-93

International Scientific Journal

published monthly by the

World Academy of Materials

and Manufacturing Engineering

© Copyright by International OCSCO World Press. All rights reserved. 2015

Study of deflocculation of white clay for

obtaining ceramic proppants fabrication

in spray dryer

M. Małek*, P. Wiśniewski, J. Szymańska, M. Koralnik J. Mizera,

K.J. Kurzydłowskia Faculty of Materials Science and Engineering, Warsaw University of Technology,

* Corresponding e-mail address: marcin.malek@inmat.pw.edu.pl

ABSTRACT

Purpose: The aim of the paper is to present the properties of ceramic slurries based on Polish raw material – white clay.

Design/methodology/approach: Test simulations were performed using mechanical mixer with rotation speed of 300 rpm. To characterize white clay microstructure SEM Hitachi SU-70 was used. For better investigation of white clay Zeta potential and grain size were done.

Findings: As a result of conducted rheological properties of new slurries based on Polish raw material exhibits stable properties in time and meet standard industrial requirements. Ceramic slurries have very promising properties and it is possible to applicate them to ceramic proppants fabrication in spray dryer.

Research limitations/implications: The main limitation is lack of possibilities to modification the rheological properties using additional chemical binders. Polish industry requires to use water as a main binder and max few wt.% of deflocculant additives. This limitation affect on the solid concentration of ceramic slurries and presented slurries had only 45 wt.%. The presented results of experimental studies will be used for developing a parameters of proppants fabrication details.

Practical implications: Presented investigations are the part of a new ceramic slurries fabrication which are intended to consist in future with three Polish raw materials as a mix of white clay, bauxite and kaolin.

Originality/value: This is one of first research to produce ceramic proppants using slurries, spray dryer and Polish raw materials. In future to take care of ecology, environment and modification properties of ceramic slurries Polish ashes from waste industry production will be added.

Keywords: Ceramic slurries; Deflocculant addition; Proppants fabrication; Raw materials; Shale gas extraction

Reference to this paper should be given in the following way:

M. Małek, P. Wiśniewski, J. Szymańska, M. Koralnik J. Mizera, K.J. Kurzydłowski, Study of deflocculation of white clay for obtaining ceramic proppants fabrication in spray dryer, Archives of Materials Science and Engineering 75/2 (2015) 89-93.

MATERIALS MANUFACTURING AND PROCESSING

90 90

M. Małek, P. Wiśniewski, J. Szymańska, M. Koralnik J. Mizera, K.J. Kurzydłowski

Archives of Materials Science and Engineering

1. Introduction

The growing mining industry of petroleum during the

exploration and exploitation of already discovered bed

such as oil and natural gas, accompanied by accidental

discoveries of unconventional of new materials for

energy. In past, when it was the first discover of un-

conventional bed of shale gas and its extraction from

shale rock had a marginal share in the natural gas

processing. For economy reason this beds were not taken

into account in terms of their suitability for use. The fact

is that technology of its acquire was not well known. This

technology did not allow to precision geological research

of deposit [1,2].

The increase of the oil and gas prices was caused by

a rapid process of industrialization and a global depletion

of shallow and easily accessible reserves. Scarcely in the

last several decades it was realized that large bed of

unconventional sources may be use for energy production.

This kind of reserves are contained mainly in three types:

tight gas, natural gas shale and methane from coal seams.

The development of mining technologies significantly

reduces the cost of shale gas exploration and exploitation.

For economic reasons, the most popular is the acquisition

for natural gas accumulated in the shale and tight. Process

of exploration these beds is of the highest importance for

US industry and economy. In this century, mining techno-

logy of this type of natural resources are supported by

government tax credit systems [3-5].

Conventional natural gas is relatively easily to

acquiring due to the fact it moves in the rock, and accu-

mulates on comparatively slightly exploited. Whereas

unconventional beds of shale gas are located in deep

underground, often at a depth of several kilometers [6].

Due to the deep location and complicated and complex

procedure of the extraction of gas from shale rock is not

economically justified. Process of production is carried

out in two ways. The firs is horizontal drilling. This

process is performed by vertical well bore to a depth of

residual deposit and then drilling the literally until reach

to shale beds. The second method is a fracturing process.

It involves making several vertical drilling and then

injecting fracturing fluids containing fracturing substance.

Operating pressure of the fracturing fluids causes rock

cracking and release of these gas. Fracturing fluid

contains the sand, which will be replacement by ceramic

proppants and whose function is to prevent squeezing

rock and slotted casting to permit the free flow of gas

[7,8].

2. Experimental methodology

Tested materials were the samples of ceramic slurries

based on white clay and main binder which was a water.

Additionally for better liquidation and increase the solid

content of white clay five deflocculant (in amount

0.25 wt.% with respect to clay) such as: CS, DISPEX A-40,

DISPEX N-40, DURAMAX, POLIKOL were added. The

references specimen was slurry without additives. To

prepare ceramic slurries mechanical stirrer was used.

Rotation speed of the mixer was 300 rpm. Time of mixing

was 3 h. Whereas proceeded to measured dynamic

viscosity of investigated slurries on Anton Paar Rheometer,

using coaxial cylinders method. Rotation of spindle was

10-200 rpm, 10 s in 200 rpm, and 200-10 rpm. To better

characterization white clay SEM images on Hitachi Su-70

microscope were done using SE upper mode with 5 kV.

Potential Zeta was measured by Zeta izer NANO ZS. To

determine grain size of investigated powder using a laser

diffraction method (Horiba LA-950).

3. Test Results

Figure 1 shows SEM images of investigated powder

coming from Polish raw materials white clay. Image

present large particles of powder forming agglomerates on

all researched area. On the surface small particles of white

clay are observed. Natural white clay occurring in Poland

include high value of humidity.

Figure 2 present the results of measuring grain size of

characterized powder. In this case graph of relative

frequency to size exhibit bimodal character. Particles of

investigated white clay are in the range of 0.30-1 µm and

1.5-45 µm. Mean particle size is 11.1 µm.

Research distribution of Zeta potential with respect to

pH shows Figure 3a.

In case of application polyacrylate deflocculant

(DISPEX A-40 - solution of ammonium polyacrylate and

DISPEX N-40 - solution of sodium polyacrylate), the Zeta

potential is significantly decreased (Figs 3b,c). When

DISPEX A-40 was used in the pH range from approx.

5 - 10 (Fig. 3b), particles exhibits constant Zeta potential at

approx. -50 mV. In contrast with DISPEX N-40, Zeta

potential of the particles adsorbed on the surface of the

substance is stable in a pH range approx. 4-9 (Fig. 3c). This

type of plateau is advantageous from a technological point

of view, because it allows for small fluctuations in the pH

of the slurry, while maintaining the stability of the impact

between the particles and therefore stable properties

characteristic of the slurry.

1. Introduction 2. Experimental methodology

3. Test results

91

Study of deflocculation of white clay for obtaining ceramic proppants fabrication in spray dryer

Volume 75 Issue 2 October 2015

a)

b)

Fig.

(a -

F

F

of in

force

0,

1,

2,

3,

4,

5,

6,

7,

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9,

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Fig. 2. Grain si

Figure 4 presen

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es are higher r

00

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POLIKOL

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DISPEX A

1 wt.% DI

-50

-40

-30

-20

-10

0

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[mV

]

shear rate pa

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erved for REF

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h DURAMAX a

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ISPEX N-40 ad

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articles degrad

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ty. The highest

FERENCES slu

lowest value o

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12

12

12

92 92

M. Małek, P. Wiśniewski, J. Szymańska, M. Koralnik J. Mizera, K.J. Kurzydłowski

Archives of Materials Science and Engineering

Fig. 4. Flow curves of shear stress vs. shear rate

distribution of investigated ceramic slurries

Fig. 5. Flow curves of viscosity vs RPM distribution of

investigated ceramic slurries

Distribution of viscosity vs. RPM is present of Fig. 5.

For all tested samples, observed viscosity decrease with

increasing rotation speed. The highest value of viscosity

exhibit REFERENCE sample - 12.6 Pa·s., but the lowest

value exhibit slurry wit DURAMAX addition - 0.41 Pa·s.

The mildness decrease was observed for the slurry with

POLIKOL addition.

4. Conclusions

Studies shows a positive effect of deflocculates addition

to properties of received ceramic slurries. It has been found

that selected deflocculates use generally reduces the shear

stress and viscosity of investigated ceramic slurries. The

most useful substance for choosing composition of raw

materials was DURAMAX. Also DISPEX A-40 and N-40

decrease significantly researched parameters of slurries.

Whereas POLIKOL shows the lowest value of defloc-

culation. The obtained results are the base to investigated

different composition of ceramic slurries and also can be

useful in other areas of ceramic technology and proppants

received in spray dryer.

Acknowledgements

Financial support of BLUE GAS financed from The

National Centre for Research and Development- Project “

Optimizing the lightweight high strength and low specific

gravity ceramic proppants production technology

maximally using naturally occurring Polish raw materials

and fly ash , No. BG1/BALTICPROPP/13 is gratefully

acknowledged.

Additional information

Selected issues related to this paper are planned to be

presented at the 22nd Winter International Scientific

Conference on Achievements in Mechanical and Materials

Engineering Winter-AMME’2015 in the framework of the

Bidisciplinary Occasional Scientific Session BOSS'2015

celebrating the 10th anniversary of the foundation of the

Association of Computational Materials Science and

Surface Engineering and the World Academy of Materials

and Manufacturing Engineering and of the foundation of

the Worldwide Journal of Achievements in Materials and

Manufacturing Engineering.

References

[1] D. Mader, Hydraulic Fracturing and gravel parking,

developments in petroleum science 26, Elsevier, 1989.

[2] M.J. Economides, D.A. Hill, C. Ehlig-Economides,

pertoleum production systems, Prentice Hall, 1993.

[3] R. Khosrokhavar, S. Griffiths, K.H. Wolf, Shale gas

formations and their potential for carbon storage:

opportunities and outlook, Environmental Processes 1

(2014) 595-611.

0

20

40

60

80

100

120

0 50 100 150 200 250 300

Sh

ear

Str

ess

[Pa

]

Shear Rate [1/s]REFERENCE CS DISPEX A-40

DISPEX N-40 DURAMAX POLIKOL

0

2

4

6

8

10

12

14

0 20 40 60 80 100 120 140 160 180 200 220

Vis

cosi

ty [P

a·s

]

RPMREFERENCE CS DISPEX A-40

DISPEX N-40 DURAMAX POLIKOL

References

Acknowledgements

4. Conclusions

Additional information

93READING DIRECT: www.archivesmse.org

[4] M. Kulkarni, O.O. Ochoa, Mechanics of light weight

proppants: A discrete approach, Composites Science

and Technology 72 (2012) 879-885.

[5] R.F. Aguilera, M. Radetzki, The shale revolution: Global

gas and oil markets under transformation, Mineral

Economics Raw Materials Report 26 (2013) 75-84.

[6] P.D. Warwick, W.A. Ambrose, J.C. Pashin, A.H.

Johnson, C.D. Jenkins, Unconventional energy

resources: 2011 Review, Natural Resources Research

20/4 (2011) 279-328.

[7] X.L. Zhang, L.Z. Xiao, L. Guo, Q.M. Xie, Investigation

of shale gas microflow with the Lattice Boltzmann

method, Petroleum Science 12/1 (2015) 96-103.

[8] Yu.A. Strizhakova, T.V. Usova, Environmental

problems of oil shale processing industry, Solid Fuel

Chemistry 41/3 (2007) 174-178.