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21/10/2017

Design and fabrication of small scale
gravure printing machine for
composite membrane synthesis

Student Details:

Name: Abdul Ali Mohammadi
ID: S3480258
Title: OENG 1074- Final Year Research Project part AMechanical Engineering - Semester 1, 2017

ABSTRACT
The purpose of Nano materials such as Graphene oxide layers to make composite membranes for water
purification is currently an intense area of research that could advance current membrane technologies
...

Despite, scaling up those composite membranes to large area is still a challenge for researchers
...
If these issues are solved, there will be an increased interest from
the government sector as well from different organizations and companies who could invest on this
technology
...
Once we
reduce the viscosity of the GO, a gravure printing machine can be applied to Nano’s viscous Graphene oxide
flakes to obtain highly uniform, continuous, thin films of multi-layer Graphene oxide on a support membrane
providing a final composite membrane
...
Consequently, for durability and strength of the GO flakes & alteration it is
required to use another porous membrane that we chose to be a thin Nylon substrate of micro size pores
used for fabricating the GO membrane composite
...
The as such fabricated membranes are then experimentally tested as
finale composite membrane in nanofiltration and RO system to compare their performances
...
However, water permeation is expected to be inversely
proportional to membrane thickness
...

From the experimental result, it was found out that the permeability of shear-aligned membrane is much
higher than of vacuum filtration process, regardless of the increased final thickness
...


OENG 1074 Final Year Research Project part A- Mechanical - Semester 1, 2017

Page 1

ACKNOWLEDGEMENTS

I would like to thank my first supervisor Dr Stefania Castelletto and my second supervisor Dr Abhijit Date for
their guidance, weekly meeting, assistance and advising regarding design and fabrication of gravure printing
machine and all experimental work during the semester
...
I would also like to thank Master student Mr Priyamjeet Deka who
provided constructive suggestions and work closely with me during semester for all experimental work
...
1
1
1
...
2
1
...
4

2

INTRODUCTION
...
4
Nonporous Graphene membranes
...
6
Vacuum filtration
...
7

2
...
1
Scope of Research
...
1
...
8
2
...
8
2
...
9
2
...
10
2
...
10
2
...
11
2
...
11
2
...
11
2 x Pinion Gears
...
9 Bearing selection
...
10
Washer
...
10
...
13

3

PREPARATION OF graphene OXIDE SOLUTION –Water reduction process
...
1 Membrane fabrication - Shear alignment
...
2 Shear alignment by Vacuum filtration
...
2
...
18
3
...
18

4

Result and Discussion
...
19
5

Conclusion
...
22

7

Appendix
...
Having
healthy water for human needs is known as a factor in civilization, so that it has always been respected by
societies
...
Over more than 1
...
Water
scarcity is a big progressing matter which cause not only by destructive climate changes and increasing
water and agriculture damage as well as human activities that consume water trough evaporation or
incorporation ( Fasel, Bréthaut et al
...

The water scarcity is not because of less water, though the earth’s most parts rounded by the water, it is
because of not being enough clean and sweet water in the world
...

Researches show that about 97
...
So, in order to
save the world’s population, it is necessary to find some solutions to overcome the water sacristy(Dervin,
Dionysiou et al
...
For instance, it is necessary to find a methods treating salty water and provide safe
water which is still a major global issue
...

They added that some process such as desalination can significantly influence and affect the future of fresh
water supplying in the world
...
2017)
...
These methods are
not costly and seem to be straight forward
...
2016)
...

These methods are Reverse Osmosis & membrane distillation
...
Comparing both methods, they consume a bit amount of energy but only differences is
between this two that each of them require certain processes and reverse Osmosis require less energy and
has four process such as pre-treatment, pressurization, separation & stabilization(Macedonio and Drioli
2017)
...
1

Desalination

Desalination is a water treatment process that removes mineral and salt components from water
...
During the heating process there will be create some temperature gradient which
will cause vapour pressure differences
...
2016)
...
Since then, a lot of studies and laboratory investigation have been done
to develop this process (Sanmartino, Khayet et al
...

Membrane desalination method has its advantages and disadvantages as well that we cannot ignore them at
all
...


OENG 1074 Final Year Research Project part A- Mechanical - Semester 1, 2017

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Figure 1: Schematic diagram of desalination method
...
Some of disadvantages of this method as follow





Lack of high quality of membranes
Its high cost for desalinating sea water
Short permeate flux
High initial cost & membrane wetting

However, Membrane- based process include Nano filtration, reverse osmosis and forward osmosis widely
used in desalination process (Sanmartino, Khayet et al
...
All this process develops a residue with huge
salt concentration called brine which depends on the type of the salinity of water
...
2

Nonporous Graphene membranes

Nonporous Graphene oxide has thin structures and large surface which caused it to be counted as
separation membranes if they were able to send the molecules toward the carbon planes
...
2016)
...
Suk and
Aluru investigated on this field and if it is possible, disclose nonporous membranes into the graphene’s
construction in order to form and create the final desalination membranes
...
After that the researchers who were studying and researching in
the Manchester University, explained that there are some Graphene oxide membranes in the form of liquids,
vapours and gases which can facilitate unlimitedly water infiltration (de la Fuente Vornbrock, Sung et al
...
Later they had been investigated and studied the behaviours and characteristics of Graphene oxide
membrane more closely which had prepared by a simple drop casting method
...
By continuing the investigations
and researches , they claimed that if they want to improve and make possible the industrial production of
Graphene oxide water filters, they need to find those approaches that lead them to go through approaches
in which they be able to produce large area Graphene based membranes(Dervin, Dionysiou et al
...
By
doing the efforts and studying more and more, they concluded that a scalable, liquid film processing
approach can help them to reach their goals of producing large area Graphene based membrane(de la

OENG 1074 Final Year Research Project part A- Mechanical - Semester 1, 2017

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Fuente Vornbrock, Sung et al
...
Later, after that, another investigator who was called Akbari et al had
started to investigate on this field, and he focused more on the traditional methods
...
In addition, by absorbing
the water of the primary solution which was using polymer hydro gel beads, he could successfully produce
congregated nematic scatterings of Graphene oxide(Dervin, Dionysiou et al
...
Moreover, he said that if
they support the use of a strict septum and shear force alignment, they will be able to scatter the sticky fluid
which had been arranged uniformly, and based on that they can produce malty-layered Graphene oxide thin
film (Dervin, Dionysiou et al
...

1
...
However, Reverse
Osmosis removes both organic and inorganic compounds from water & eliminates the inorganic solutes,
which contains bacteria-end toxin & other unwanted substances
...
The aim of desalination performance of the
membrane oxide was carry out in terms of NACI & water Flux rejection
...
(Vatanpour, Safarpour et al
...
This
method is more convenience and simple which does not require professional person to install and operate it
...
This method is widely have been used by industries for the purpose of water purification
...
2017)
As the figure above explains the brine leaving the RO modules is fed to the ADS system, in the RO system an
open air water storage tank must be added as an energy recovery device
...
2017)
...
This method is simple as the water contains salt will be pump in to the membrane which only
allows a small amount of fresh water gets through to the membrane and the salt water return back to the
tank
...
4

Vacuum filtration

Vacuum filtration is another method of depositing composite membranes which have been used in
laboratory for alignment purpose
...

Vacuum filtration process is not easy comparing to shear alignment method
...
In 1957, a
chemical engineer, James R, Brown noticed during his investigations, which utilizing the vacuum filtration
process requires Buchner funnel along with a side arm flask and “this process in way faster than gravity
filtration reason being in this process, the solution and air are forced through the filter paper by the use of
reduced pressure (Brown, 1957)
...


, we will be capable to boil them under the

However, it is illustrated in figure 3, that the system is made of simple mechanism such as a side arm flask
and a Buchner funnel
...
5 mbr, and then the
flexible nylon substrate can be placed on top of the filtration unit for filtration process
...
Then, applied pressure will absorb the water slowly and only GO membrane solution will
deposited on top of the substrate
...


Figure 3: Schematic diagram of Vacuum filtration (MRIT laboratory)

2

GRAVURE PRINTING MACHINE

2
...
1 Scope of Research
Innovation of gravure printing machine started at the early of fifteenth century, and it is one of the oldest
printing technologies that carried out directly to print large scale industries and commercial uses
...
It is well
accepted as one of the best and fastest mass fabricating technique with a speed range of 400 m/min to 600
m/min (Voigt, Mackenzie et al
...
This type of printer requires some components such as doctor blade,
inks with low in viscosity and rapid drying
...
(Szentgy
örgyvölgyi 2016)
...
This is one of the best and easy
method for alignment of Graphene membrane flakes by applying a shear force depends on the thickness of
the flakes
...


OENG 1074 Final Year Research Project part A- Mechanical - Semester 1, 2017

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Figure 4: Schematic diagram of shear alignment method(Akbari, Sheath et al
...
In their work, they demonstrated thin film transistors on
flexible substrates such as nylon using gravure printer and a mixture of other printing techniques can
produce a large scale of nano composite membranes materials and it can be printed high –quality patterned
films materials for various applications
...
2010)
2
...
2 Grave printing machine fundamentals
Gravure printing a machine is made of some simple mechanism that uses a metallic roll , as well the gravure
roll which is pressed against each other with use of an imprint roll during operation in opposite direction,
in order to transfer the substrate between two rollers to obtain a great continuous alignment of GO
membranes
...
The only difference is that the printer
does not require some parts such as doctor blade, ink unit, drying unit and some other parts
...
It also includes a web or substrate from a
continuous roll is passed over the image surface of a revolving gravure cylinder (Publication Rotogravure
Printing)
...
This allows the upper pressure align the
Graphene Oxide solution in one direction smoothly
...
2010)
...

2
...
The rollers tightly press against
each other in opposite direction in order to take the substrate in to the gravure cylinder during printing
process as represented in figure 5
...
2004)
The weight of the rollers depend on the type of the materials and their application for example, for small
scale laboratory purpose can be 400 gm to 5 Kgm but for large area- application, it can be a 100 kg to
tone
...
3

Gravure cylinder

Gravure cylinder is mounted above the impression roller and it is rotate by frictional force operated
manually or automatically can be rotate at high or low speed ( RPM) with a diameter of 25 mm and length of
142 mm
...
75mm
...


Figure 7:Parts of gravure cylinder(Tech
...
Five important components of this roller are:


Axis – a visible line that passes through the centre of the length of the cylinder
...


OENG 1074 Final Year Research Project part A- Mechanical - Semester 1, 2017

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

Face length – the distance from one end to other end of the cylinder
...




Circumference- the distance from the edge of the end view
...
To have a great mechanical strength and stiffness, it required to
drawn inwards and is supported by additional steel discs
...
2004)
...
4

Impression Roller

Impression roller is a steel tube roller, with a diameter of 25 mm and length of 142 mm, establishing a nip
shape where the substrate passes
...


Figure 8: A schematic diagram of Impression Roller

It is normally smaller or the same size of the gravure cylinder and it operates at high RPM
...
Speed of the
impression roller and it is pressure can be adjust it to the least minimum amount of pressure require to
generate high quality printing press (Vornbrock 2000)
...
Impression pressure or applied force can be evaluate in pound
per linear inch depends on the substrate’s hardness
...
25mm, balance in a fixed shape in order to eliminate mechanical excessive vibration because
uncontrolled vibration can cause poor printing quality, wrinkling and reduce printing efficiency of the
substrate during printing operation
...
5

Nip point

The contact point between impression roller and gravure cylinder is called Nip Point and it is every important
to consider when we are applying force because the pressure should be distributed equally along the whole
length of the two rollers
...
In other
hand, if the pressure increases rapidly it may damage the GO flakes
...
6

Gears

Gear is one of the most useful simple mechanism are used in vehicles and power trains having a cut teeth
that mesh with another tooths in order to rotate the shaft and transmit high torque
...
Today, nearly most devices in the industry have gears
...
They consist of teeth due to reduce speed and increase power and are
mounted in parallel and straight to the axis
...
7

Spur Gear

Spur gear is one of the simple straight cut gears consist of a disk with teeth is used in gravure printing
machine in order to rotate the gravure cylinder and impression roller
...
These types of gears are noisy and cause vibration and it is not suitable for the
large machinery parts such as cars and production machines
...
2017)
...
8

Select the gears according to Australian Standard
...

Gear design calculations can be based on existing data
...

Select the gearbox according to the design requirement
...
9

Bearing selection

Bearings are simple supporting mechanism are used to support a shafts, hubs and moving parts
...
In order to fit impression and gravure roller we are required to
select some bearings According to SKF® rolling bearings catalogue(AS-1403 2004)
...
2017)
...
25 mm, 2x15 mm and 18 mm
...

2
...
It also used as a locking device to avoid
excessive vibration rattling in machinery parts
...
they are flexible and can resist higher loads to ensure the rollers tight enough with any
motion while in printing operation(Simmons, Maguire et al
...


Figure 10: A schematic view of washers used on Gravure printing machines to hold parts together
...
10
...
We are required to assemble the components
...
The gap between two rollers is almost adjusted to zero which
is hard for the nylon subtracts to get through
...

However, in printing process if the substrate is thicker than the gab size between the two rollers, gravure
roller can be pushed upward automatically which is acting as a spring force in order to print the membrane
on top of nylon substrate
...
Since this substance can disperse in the water so easily (Akbari, 2016)
...
8 mg/ml of Graphene Oxide solution can disperse in only 14-17 ml of water
...
They can absorb large amount of water in
their three dimensional network because they have strong hydrophilic structures and higher water
absorption capacity (Dervin, 2016)
...

After adding some hydrogel beads directly in to the Graphene Oxide solution, we kept the GO solution in
vertical position for almost an hour to allow the beads absorb water molecules as much as possible
...
Therefore, they can
absorb the molecules of water and the concentration of Graphene Oxide solution will increase more and
more, that will cause the viscousness of Graphene Oxide solution
...
By removing and taking out the Hydrogel beads from the Graphene Oxide solution, we
can measure the remaining Graphene Oxide solution
...
It is clearly shown in figure 13
that the hydrogel beads has increased in size and the volume of the GO solution has decreased from 21
mg/ml to 13 mg/ml
...


In conclusion, by following this process, we are capable to reduce the amount of water from the
Graphene Oxide solution to achieve desirable concentration
...
1

Membrane fabrication - Shear alignment method

One of the strategies which were used to transfer Graphene Oxide is called role to role (Sear alignment)
process which is using a gravure printing machine
...
Examining more closely SAM
method in order to see that the process is acceptable and accurate for shear alignment of Graphene oxide as
well for other composite nano particle materials (Akbari, 2016)
...
However, water contains of GO solution has been reduced as
much as possible to get a zero- shear viscosity of GO previously
...


Figure 14: Alignment process of GO flakes by gravure printing machines
...
Role and role transferring method enforce
mechanical imperfection in the Graphene films
...
Consequently, while doing the research and testing the
methods; I have noticed that there are some cracks and voids which is not a big issue
...
In
addition, the thin nylon film that contains membrane needs to be dried quickly after the alignment process
as shown in figure 15
...
It may take up to 2 or 3 hours to complete the
separation process
...
After that, using Scanning electron microscopy (SEM) to measure
the thickness of the membrane flakes
...
44 nm

However, the membrane thickness produced in shear alignment method is a bit large than we expected
because in SAM, we used large crystal Graphene oxide
...


Figure 17: Membrane surface images taken by optical microscope at RMIT lab

OENG 1074 Final Year Research Project part A- Mechanical - Semester 1, 2017

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Figure 18: SEM image, a top view of the membrane single flakes
Based on SEM Quanta image, the surface of a single GO membrane flakes shown in figure 18, demonstrates
continuity and conformity of shear alignment method
...
The nematic phases of flakes can be randomly distributed in the direction
of shear stress at higher shear rates which produce less physical cooperation of the flakes between each
other (Akbari, 2016)
...
2

Shear alignment by Vacuum filtration

In vacuum filtration process, 10 mg/ml of GO and methyl red solution has been test it and then it reduce via
hydrazine vapour using the same method as used in SAM
...
89 nm (Priyamjeet)
Comparing the thickness of the two samples, the molecules are almost the same but in vacuum filtration the
membrane thickness is different
...


OENG 1074 Final Year Research Project part A- Mechanical - Semester 1, 2017

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Figure 20: Membranes surface images taken by optical microscope
Based on optical microscope image shown in figure 20, the surface of the membrane produced by vacuum
filtration is not highly aligned; there is some abnormal behaviour between the flakes
...


3
...
1 Reduced GO membrane
In order to get a good permeability and salt rejection, two membranes were annealed in a furnace for up to
4 hours at a temperature of 180
to make GO membrane more stronger and it can minimize the
mechanical strains which were used by to Graphene on substrates; therefore the transferred Graphene has a
relatively uniform morphology that has less defective structures as represented in figure21- (A) and (B)
...

3
...
The system does not require any degasification since it declines contaminants depending on both
size and ionic charge
...
As shown in figure 22, we set up the RO system according to the lab procedure
...
After that, using 2 litres of water at 2
...
8
...

Pumping the salt water into membrane with a pressure of 1
...
Since there are

some inter layer spacing between the Membrane particles, the molecules of water can flow
through these spaces
...
Repeating the trails for three times we can get more accurate result
...
Finally all the experimental result has been clearly
recorded
...
43%

Vacuum Filtration (300 µL) (13mg/mL) S

45%

42%

40%

42%

1
...
19%

40%

1
...
The last column on the table 1- percentage salt rejected- represents the amount of salt reduced from
water
...
5 %
...
5 % to 1
...
The following formula was used to calculate the amount of salt rejected:

Similarly, for nano filtration

Graph 1

Salt Rejection
70%

63%

58%

60%

52%

57%

52%

42% 48%
40%

47%
42%

2nd

3rd

Average

Column1

Percentasge (%)

45%

1st

50%

Column2

Column3

Column4

40%

44%

40%
30%
20%
10%
0%

No of Attempts
Shear Alignment Method(800µL)(15mg/mL) L

Vacuum Filtration (300 µL) (13mg/mL) S

Vacuum Filtration(800 µL) (13mg/mL) S

Nanofiltration(500 µL) (13mg/mL) S

Figure 23:The blue colour represents the % of salt rejection of shear alignment method, light gray and orange colour represent the % of
salt rejection of vacuum filtration method and yellow colour bar represents the % of salt rejection of nano filtration method

Based on our investigations, we obtained the result in Figure 23 which we can clearly see that for the shear
alignment method we obtained an average of 57 % salt rejection comparing to vacuum filtration which is 42
% salt rejection
...
5% to 1
...

However, the salinity of membranes fabricated by vacuum filtration method was decreased from 2
...
44% and 1
...
We also compared our result to nano filtration
method that had only 40% salt rejection, which is shown in yellow colour in figure 23
...
5 to 1
...
Another reason for
OENG 1074 Final Year Research Project part A- Mechanical - Semester 1, 2017

Page 20

higher salt rejection compared to vacuum filtration is that the concentration of GO solution used in shear
alignment method is higher than vacuum filtration process
...
Therefore, when there is a higher salt rejection of the brackish water for thicker film
...

Table 2

Permeability (L/m2hr)
GO membranes

1st

2nd

3rd

Average

Shear Alignment Method(800µL)(15mg/mL) L

47

33

18

32
...
0

Vacuum Filtration(800 µL) (13mg/mL) S

19

16

15

16
...
0

Graph 2

Permeability (L/m2hr)

Water Permeability
47

50
40

32
...
0

22

16
...
0

10
0

0

0

0

0

No of Attempts
Shear Alignment Method(800µL)(15mg/mL) L

Vacuum Filtration (300 µL) (13mg/mL) S

Vacuum Filtration(800 µL) (13mg/mL) S

Nanofiltration(500 µL) (13mg/mL) S

Figure 24: The orange colour represents the permeability of shear alignment method, light gray and yellow represent
permeability of vacuum filtration and blue colour bar represent permeability of nano filtration method
...
So as the time interval is increased for each 20 mins, the permeability
rate is decreasing as such which confirms the degradation of the membrane for every 20 mins
...
Therefore the correlation between thickness and water permeation is usually
insignificant
...

When membrane thickness is increased, water permeation is expected to decrease because the water will
have to travel over a longer distance, and vice versa
...
The SAM system had a better
water permeability of 47
which is almost better than vacuum filtration (Akbari, Sheath et al
...
We also could get a better water permeability and salt rejection if we used small crystal Graphene
oxide in shear alignment method (SAM) to produce membrane for RO system
...
By utilizing these methods, though we cannot provide all
amount of necessary water for all the people around the world, we can at least solve the problem of millions
people around the world and decrease the treat of water scarcity in some places
...
The thickness of Graphene-based membranes produced by
vacuum filtration is very small compared to the shear alignment method and likely the separations of
individual layers of GO larger
...
However, water permeation is expected to be inversely proportional to membrane thickness
(Akbari, 2016)
...

From the experimental result, it was found out that the permeability of shear-alignment membrane is much
higher than of vacuum filtration process, regardless higher thickness of the membrane
...


6

REFERENCE
1
...
, et al
...
"Large-area graphene-based nanofiltration membranes by shear alignment
of discotic nematic liquid crystals of graphene oxide
...

2
...
S
...
(2017)
...
" Desalination 408: 13-24
...
AS-1403 (2004)
...
pdf>
...
, A
...
(2010)
...
"
Organic Electronics 11(12): 2037-2044
...
Dervin, S
...
(2016)
...
" Nanoscale
8(33): 15115-15131
...
Eykens, L
...
(2017)
...
" Separation and
Purification Technology 182: 36-51
...
Fasel, M
...
(2016)
...
" Environmental Science & Policy 66: 140-150
...
Macedo Reference and reviewed literature nio, F
...
Drioli (2017)
...
4 Fundamentals in Reverse
Osmosis
...
Oxford, Elsevier: 79-94
...
Marques, P
...
(2017)
...
" Mechanism and Machine
Theory 113(Supplement C): 126-140
...
Sanmartino, J
...
, et al
...
Chapter 4 - Desalination by Membrane Distillation A2 - Hankins,
Nicholas P
...
R
...
Boston, Elsevier:
77-109
...
Seera, M
...
(2017)
...
" Applied
Soft Computing 57(Supplement C): 427-435
...
Simmons, C
...
, et al
...
Chapter 16 - Nuts, bolts, screws and washers
...
Oxford, Butterworth-Heinemann: 117-130
...
Szentgyörgyvölgyi, R
...
12 - Gravure Printing
...

14
...
, A
...
" ...
"
15
...
A
...
11 - Fasteners
...

16
...
, et al
...
"A thin film nanocomposite reverse osmosis membrane containing
amine-functionalized carbon nanotubes
...

17
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...
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...
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Vornbrock, A
...
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Shenvi, Seema S
...
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...


OENG 1074 Final Year Research Project part A- Mechanical - Semester 1, 2017

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Title: Design and fabrication of small scale gravure printing machine for composite membrane synthesis
Description: The purpose of Nano materials such as Graphene oxide layers to make composite membranes for water purification is currently an intense area of research that could advance current membrane technologies. It is important to find out some approaches to be able to use Graphene based membranes in large areas. Despite, scaling up those composite membranes to large area is still a challenge for researchers. In consequence, more research and investigations are needed on the approaches that can be used to produce large- area Graphene based membranes. If these issues are solved, there will be an increased interest from the government sector as well from different organizations and companies who could invest on this technology. Generally, to achieve the desired viscosity of Graphene oxide solution in order to be able to fabricate Nano-composite membrane, it is required to reduce the concentration of the water as much as possible. Once we reduce the viscosity of the GO, a gravure printing machine can be applied to Nano’s viscous Graphene oxide flakes to obtain highly uniform, continuous, thin films of multi-layer Graphene oxide on a support membrane providing a final composite membrane. A single Graphene layer thickness is below nanometre and can only be seen by electron microscopes. Consequently, for durability and strength of the GO flakes & alteration it is required to use another porous membrane that we chose to be a thin Nylon substrate of micro size pores used for fabricating the GO membrane composite. The aim of this research is implement the design, manufacturing of a small gravure printing machine for composite based membrane fabrication, where shear alignment of the GO is achieved. The as such fabricated membranes are then experimentally tested as finale composite membrane in nanofiltration and RO system to compare their performances. Based on our experimental investigation, we can say that shear alignment method has better salt rejection compared to vacuum filtration (an alternative method to deposit GO on the support membrane) in regards to nano filtration and reverse osmosis capability. However, water permeation is expected to be inversely proportional to membrane thickness. When membrane thickness is increased, water permeation is expected to decrease because the water will have to travel over a longer distance, and vice versa. From the experimental result, it was found out that the permeability of shear-aligned membrane is much higher than of vacuum filtration process, regardless of the increased final thickness. So as the time interval is increased for each 20 mins, the permeability rate is decreasing as such which confirms the degradation of the membrane over time.

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