Presentation on three favourite technologies.

1. Topic 1: Mining metals from desalination brine

2. Seawater contains large quantities of valuable minerals, some of which are very scarce and expensive in
their land-based form. However, only a few minerals, the ones in high concentrations, are currently mined
from the sea.
Due to recent problems associated with land-based mining industries as a result of depletion of high-grade
ores, sustainable water and energy demand and environmental issues, seawater mining is becoming an
attractive option.
Oceans and seas cover nearly three-quarters of the earth's surface and contain about 1.3 × 1018 tonnes
of water.
They are composed of 96.7% water and 3.3% dissolved salts. This concentration of salts works out to be
approximately 5 × 1016 tonnes of salts which constitutes much more than most minerals that are available
as land-based reserves and annually mined from lands (Fig. 1).
Almost all elements in the periodic table can be found in seawater although many are at very low
concentrations.
The main ions which make up 99.9% of the salts in seawater in decreasing order are: Na+ > Mg2+ > Ca2+,
K+ > Sr2+ (for cations) and Cl− > SO42− > HCO3− > Br− > BO32− > F− (for anions).

4. Minerals have been mined from seawater since ancient times. It has been recorded that common salt (NaCl)
was extracted even before 2000 BC in China and also in the Old Testament period. Currently the four most
concentrated metals – Na, Mg, Ca and K – are commercially extracted in the form of Cl−, SO42−, and
CO32−. Mg is also extracted as MgO. Mineral elements with low concentrations have not been recovered
from seawater because their market values are much lower than the capital and operational costs of
extraction.
However, this situation has changed in recent times with the presence of many seawater desalination plants.
Rapid population growth and industrialisation have drastically increased the demand for fresh water. Although
abundance of seawater is available, the dissolved salt concentration of 33–37 g L−1 in seawater is too high
for drinking, industry or agriculture and for this reason the water needs to be desalinised. This has resulted in
the emergence of desalination plants in many parts of the world to produce fresh water mainly using
seawater reverse osmosis (RO) technology.
During the seawater extraction process, many minerals occur as by-products in the exhausted brine. If these
minerals are economically recovered, not only would the water production cost decline, but also the pollution
problems associated with the brine disposal would to some appreciable extent abate. For example, it was
estimated that the market value of Na, Ca, Mg, and K, if they are successfully extracted from the rejected
brine of a desalination plant in Saudi Arabia, would be approximately $US18 billion per year.
1. Increased demand for clean water in many countries has necessitated cost reductions in desalination. The
cost of desalination can fall further if additional income is able to be generated from the recovery of valuable
minerals in the brine concentrate by-product of desalination.

5. 2. Developing nations can obtain affordably priced fertilisers containing plant nutrients (K, Mg, Ca, S, and B) from
seawater compared to commercial fertilisers available on the market.
3. The availability of high grade mineral ore deposits located on lands that can be easily mined is depleting
steadily, leaving more of the low grade ores found deeper in the lands and socio-economically sensitive areas.
This has increased the cost of mining. As the ore grade degrades, the production costs (water and energy costs)
increase. Some countries have restricted the mining industry's operations to protect their scarce water resources.
The advantage of seawater mining of minerals is that seawater is homogeneous and there is no mineral grade
difference as there is in the land. Energy intensive processes of extraction and beneficiation are not required for
mining minerals from seawater.
4. Land-based mining results in environmental problems that are a consequence of wastes generated and pose
health hazards to miners. Strict environmental regulations that may be imposed by governments in the future can
restrict land mining.
5. New advances in extraction methods can be applied to mining of valuable minerals from seawater.
Although methods of mining valuable minerals from seawater and seawater desalination brine have been reported
in the literature on an individual mineral basis, to our knowledge, in recent times, only the study by
Shahmansouri et al. reviewed the extraction methods of a large number of minerals in a single paper. However,
the emphasis in their paper was mainly on cost-benefit analysis for individual minerals and not between different
methods of mineral extraction. Another review of mining minerals from seawater by Bardi considered the feasibility
of extraction of minerals on the basis of the energy needed and concluded that the amounts of minerals in the sea
were much higher than those in the land reserves.

6. Nevertheless, with reference to most minerals, especially those which occur at low concentrations, the
energy requirement for their extraction was reported to be very high. This was based on the reasoning that:
firstly, the total volume of water that needed to be processed to meet the annual requirement of minerals in
relation to the total volume of water desalinated at that time (2007) (1.6 × 1010 tonnes per year) was high;
and secondly, it involved enormous amounts of energy which was expensive. However, the desalination
capacity in the world has rapidly increased in the last decade because of the increase in clean water
demand and a marked reduction in desalination cost due to significant advances in the reverse osmosis
technology.
The cost of desalinated water has fallen below US $0.50 per m3 for a large-scale seawater desalination
plant in 2010 compared to nearly US $10 per m3 50 years ago. It was estimated that, by 2030, the world
production of desalinated water would grow to reach levels up to 345 × 106 tonnes per day or 1.2 ×
1011 tonnes per year and continue to grow thereafter.
Therefore, extraction of some minerals that were not economical in the past would become economical in
the near future. Also, while the process is energy intensive and expensive for extracting minerals from
seawater, it might be economically feasible to extract minerals from nanofiltration (NF) and RO brines where
the mineral concentrations are roughly twice that of seawater and in doing so the waste stream from NF and
RO can be transformed into resources.

7. Several methods have been used to mine minerals from seawater. Recent technology advancements in these
methods have led to more promising potential of mining minerals. A detail examination is carried out on the
mechanisms, advancements and limitations of the four main mining methods:
(1) Solar or vacuum evaporation, (2) ED, (3) MD/MDC, and (4) adsorption/desorption/crystallisation.
In all these methods the mineral concentrations are increased to the level of supersaturation to enable their
crystallisation. The first three methods have proven to be suitable only for the recovery of minerals having high
concentrations in seawater where the ionic product of the constituent ions of the salt can be easily manipulated to
exceed the solubility product of the salt. Minerals which are commonly mined using these methods are NaCl,
MgSO4, Mg(OH)2, CaCO3, and Br.
The fourth method is used for minerals which can be selectively adsorbed by specific adsorbents in the presence
of other minerals and the adsorbed minerals are quantitatively desorbed and crystallised. Examples of minerals
which can be mined by this method are Li, Sr, Rb and U.
The minerals are mined directly from seawater or from the concentrated brine produced as a by-product in the
desalination process using ED, RO, NF, and membrane filtration (MF). The brine can be further concentrated by
membrane distillation (MD) and salts can be crystallised by an integrated MDC process when the concentrations
of the minerals reach the saturation point of crystallisation. The minerals' concentrations in the brine are 2.5 times
higher than that in the sea water which favours their crystallisation before or after adsorption for further
concentration. However, the competition from other minerals in the brine for adsorption will also trigger a high
reduction in adsorption.

8. There are much more minerals in the sea compared to those in land-based reserves. Given the difficulties
facing land-based mining industries such as sustainable energy and water demands, depletion of easily
available high-grade ores and environmental issues related to waste disposal and miners' health, mining
minerals from the sea is becoming more attractive. The increasing demand for clean water has led to the
installation more desalination plants worldwide. This process generates enormous amounts of brine. The
brine contains all the minerals present in the sea at nearly twice the concentration of that in seawater.
Mining minerals from these brines can offset part of the desalination cost as well as solve the brine disposal
problem.
The main methods of recovery of minerals are solar evaporation, ED, MDC, and adsorption/desorption. Of
these, the first three can recover only minerals which are found at high concentrations (Na, Mg, Ca). The
centuries-old solar evaporation method is limited in its use, in that it is mainly employed in arid regions
requiring high solar evaporation and where land is available at low cost. The new WAIV is a promising
method that may overcome these limitations. The application of ED for mineral recovery has increased with
the developments of monovalent cationic and anionic permeable membranes to separate Na, Cl, and Br
from Ca, Mg and SO4. Further, new research is in progress to develop membranes permeable to specific
individual metals such as Li. MDC is a relatively new method which has been shown to recover NaCl and
MgSO4 in laboratory studies. New membrane developments with anti-scaling and other beneficial properties
and pre-treatment of the feed water are expected to increase the applicability of this method to other mineral
recoveries. Studies have shown that using MDC has the potential to recover Li, Sr, Ba, and Ni.

9. Unlike the other methods, the adsorption/desorption method can concentrate minerals that exist at low
concentrations by selectively adsorbing a mineral and quantitatively desorbing it for evaporative
crystallisation. Though adsorbents with high adsorption capacities have been developed (MnO2-based
materials for Li, potassium metal hexacyanoferrate for Rb, and amidoxima-based materials for U), they are
not completely selective to the mineral of interest. This has led to the use of several other adsorbents to
specifically remove the minerals competing for adsorption with the mineral of interest and removal of the
competing mineral by selective precipitation. Only Li appears to have been recovered in the pure crystalline
form using the adsorption/desorption method.
The technology advancements of each method show promising potential for its application in mining
minerals from seawater brine. Nevertheless, it is still a challenge to use a single method to selectively
extract valuable minerals from complex brine matrices. An integrated approach of combining a number of
methods may be necessary to extract a specific valuable mineral of seawater brine. A similar observation
was made by Jeppesen et al. and Le Dirach et al. on the potential of mineral extraction from seawater brine
and nuclear desalination brine.80,81 In this regard, MDC appears to show promising potential in its capacity
to simultaneously produce fresh water while recovering major salts from the brine. In an integrated
approach, selective valuable minerals, even those present at very low concentrations in seawater, could be
extracted from concentrated MDC brine with a post treatment of adsorption/desorption method.

10. Topic 2: Screenless Display

11. Nowadays, advanced technologies are growing faster
wherein each technology is renewed with
implementation of new one. The current trending
display technology most commonly used in gadgets
such as tablets, smart phones, etc., is the touch-screen
display, which will become outdated in the near future.
Screenless display is the advanced display technology,
which replaces the touch screen technology to resolve
the problems and to make lives more comfortable.
Therefore, this article is intended to give an idea of the
screenless display, which transmits or displays the
information without using a projector or the screen.
By using this screenless display technology, we can
display the images directly on the open space, human
retina and also to the human brain.
Screenless Display

12. What is Screenless Display?
Screenless display is an interactive projection technology developed to solve the problems related to the
device miniaturization of the modern communication technologies. The lack of space on screen based
displays provides an opportunity for the development of screenless displays. As the name indicates
screenless display has no screen and it can be defined as a display used to transmit any data such as
pictures or videos without the help of screens.
Screenless display technology is divided into three main categories:
• Visual Image Display
• Retinal Display
• Synaptic Interface
The first category, visual image is defined as the things that can be seen by the human eye such as
holograms. The second category, retinal display – the name itself- indicates the display of image directly
onto the retina. The third category , synaptic reference which means sending information directly to the
human brain. Let us look on in detail about these three display types.

13. Visual Image Display
The visual image is a type of screenless display,
which recognizes any type of image or thing with
the help of the human eye.The following are few
examples of the visual image display: holographic
display, virtual reality goggles, heads up display,
etc. The working principle of this display states that
the light gets reflected by the intermediate object
before reaching the retina or the eye. The
intermediate object can be a hologram, Liquid
Crystal Displays (LCD)s or even windows.
Visual Image Screenless Display

14. By using the components like Helium Neon Laser,
an object, a Lens,a holographic film and mirror, the
Holographic Displays display the three
dimensional (3D) images. A 3D image will be
projected and appears to be floating in the air
whenever the laser and object beams overlaps with
each other. This display can supply accurate depth
cues and high-quality images and videos that can
be viewed by the human eyes without any need of
special observation devices. Based on the colors of
the laser projector, images are formed in three
distinct planes. Holographic displays are commonly
used as an alternative to screens.
Holographic Display

15. Heads up display are also named as transparent
displays. These displays are applied in different
applications such as aeroplanes, computer games
and automobiles, etc. Many of the users do not
need to look away from their field of view because
the device displays the information on a
windshield. An orginary heads up display
comprises of following components: a projector
unit, combiner and a computer. The projector unit
projects the image, and the combiner redirects the
displayed image by that projected image, and the
field of view are seen simultaneously. The
screenless computer acts as an interface between
the projector and the combiner (data to be
displayed).
Heads up Display

16. Retinal Display
The second category of advancement in display
system, retinal display as the name itself indicates
the display of image directly onto the retina.
Instead of using some intermediate object for light
reflection to project the images, this display directly
projects the image onto the retina.The user will
sense that the display is moving freely in the
space. Retinal display is commonly known as
retinal scan display and retinal projector. This
display allows short light emission, coherent light
and narrow band color. Let us know about this
display with the help of the following block diagram.
Block Diagram of Retinal Screenless Display

17. The block diagram of the virtual retinal display
consists of following blocks: photon generation,
intensity modulation, beam scanning, optical
projection and drive electronics. Photon generation
block generates the coherent beam of light; this
photon source make use of the laser diodes as
coherent source with retina display to give a
diffraction onto the retina of the human eye. The
light generated from photon source is intensity
modulated. The intensity of the light beam gets
modulated to match the intensity of the image.
How Vision Works

18. The modulated beam gets scanned by the beam
scanning. By using this scanning block, the image
is placed onto the retina.In this beam scanner, two
types of scanning modes takes place: raster mode
and vector mode. After the scanning process,
optical projection takes place for projecting a spot-
like beam onto the retina of the eye. The spot
focused on the eye is sketched as an image.A
drive electronics placed on the photon generator
and intensity modulator is used for synchronization
of the scanner, modulator and coming video signal.
These displays are made available in the market
by using MEMS technology.
Retinal Projection

19. Synaptic Interface
The third category, synaptic interface means
sending information directly to the human brain
without using any light. This technology is already
tested on humans and most of the companies
started using this technology for effective
communication, education, business and security
system. This technology was successfully
developed by sampling the video signals from
horse crab eyes through their nerves, and the other
video signals are sampled from the electronic
cameras into the brains of creatures.
Synaptic Interface

20. The brain computer interface allows direct interaction between the human brain and external
devices such as computer. This category can also be known by different names such as human
machine interface, synthetic telepathy interface, mind machine interface and direct neural
interface.
These are the three types of latest Screenless displays which replace the current use of touch
screen technology to fill the lack of space in the screen-based electronic displays.We hope that
the future definitely looks promising for this technology.

21. Topic 3: Body-adapted wearable electronics

22. The field of body-adapted electronics has been around for quite some time. People have been
wearing calculator watches, mobile phones, music players, ear phones and the like for many years
now. I was intrigued by the new ideas that have developed within the last few years in the way of
health monitoring devices.
There is a wristband available for you to monitor your exercise, health, behavior, and blood pressure.
It helps you to understand your exercise and sleep patterns. Also out there for you to detect your
blood pressure are ear buds. Some of the health monitoring devices are able to be embedded under
your skin or worn as a tiny patch under clothing. The sensors provide feedback for you or your doctor
to tract your vital statistics.
The vital measures include heart rate, muscle tone, body temperature, sweat, motion and the amount of
oxygen in your system. The environmental measures include location, illumination, ambient temperature,
humidity, toxicity.
A body posture detection sensor is worn to determine whether a person is exercising or performing a sport
correctly. Along with this device, another can provide calculations of how many calories you have
consumed, or your average speed and distance. This allows you to get the best performance in what you
are attempting. For those suffering chronic disease or pain management, their doctor will be able to receive
real-time information about the person’s health, so as to be able to prescribe
medications properly.

23. Alerts systems can be applied for drivers on the road to inform them of dozing off at the wheel. Firefighters have a
polo shirt with sensors that collects their vital signs, so supervisors will know when to get them out of a disastrous
situation.
The Eye Tap, which is worn in front of the eye, or Smartglasses are for wearers to use as a camera or to view
computer imagery, is being explored as a tool for people with visual disabilities to have the information directed to
parts of their retina that does not function well. Google Glass has been using them since 2013 in operating rooms,
ambulances, trauma helicopters, doctors’ offices, and also for the visually impaired on public transportation. It is
also being used in several countries during operations, to broadcast the actual surgery to other locations, and on
TV, for many doctors to be able to watch how the procedure is being performed. In Australia, the Small World
Social Breastfeeding Support Project created the first hands-free breastfeeding application for new mothers.
Wearing the Google Glass, the mothers call a consultant to have any questions they might have, answered. In a
few months, 100% of the mothers were breastfeeding with confidence.
Several more emerging technologies are currently being developed. A brain-computer interface, for people with
disabilities who can type by controlling their brainwaves, and eventually being able to operate wheelchairs using
only their thoughts. The Haptic shoe soles, using sense of touch feedback and GPS technology, these soles will
give the blind wearer vibrations to tell them when to turn or lift their feet via a voice-programmed app that reads
GPS maps planned routes. The soles have sensors to let the wearer know when to stop, and read the walkers
gestures, example, two taps means “take me home.”

24. All of these new products are a great advantage for the medical, health, and disability fields. Along
with them goes the disadvantages, until everything can be worked out. The trials that are necessary
in order to make sure the products are fit for use is the biggest hurdle. Sensors miss firing; wrong
data being sent and received; expertise needed around the eyes; missed directions for the blind
walkers; battery-life needing to be extended; the cost of research and development and of purchase;
and the right to privacy are all issues that need to be addressed.

25. References:
https://pubs.rsc.org/en/content/articlehtml/2017/ew/c6ew
00268
https://www.elprocus.com/introduction-to-screenless-
displays-and-their-types/
Body-Adapted Wearable Electronics. (2016, Apr 15).
Retrieved from https://studymoose.com/body-adapted-
wearable-electronics-essay

26. THANK YOU
FOR YOUR TIME