الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The present work summarizes a practical study of seawater membrane distillation procedures. This procedure has been carried out using exhaust energy or solar energy, leading to pure water completely free of waste and
salt. All the experiments have been done in the labs of the Shoubra faculty
of engineering in full simulation of reality.
For this purpose, many transactions were accomplished. First of all, a
module containing cooling and heating was designed and manufactured in
order to obtain the desired temperature difference at the exchanger. The
last one contains a chamber for passing the salt water (red sea water;
12,000 ppm), which was heated to 40 to 80 °C. This hot water enters the
hot chamber through a locally designed chemical membrane
polyvenyldeen fluride (PVDF ). The membrane can withstand a high
temperature of up to 260
oC, with hydrophobic pores that repel wastes and
salts and allow only water vapor to pass. After passing the membrane, the
water vapors are condensed on the cold-water chamber surface. A coldwater tank that has a cooling unit is the one responsible for supplying the
cold chamber with cold water (10 to 30 °C). The condensed vapors are
collected and analyzed to determine their eligibility for human use.
Furthermore, the following variables were utilized and taken into
consideration in the present work: Temperature effect on the hot water (the
salt water) that enters the hot chamber for distillation, as well as its effect
on the water entering the cold chamber. Taking into consideration the
water flow rates on both sides and the effect of changing the membrane
type and thickness on the permeability. All of that was studied and utilized
very carefully, leading to the following results.Increasing the hot water temperature intended to be distilled (seawater)
achieved the best findings, especially around 80 °C. Moreover, decreasing
the cold-water temperature to the least accomplished temperature of 10 °C
led to the best results. Furthermore, the higher the temperature difference
between the cold and the hot chamber, the higher the water permeability
through the membrane that is achieved and condensed.
In addition, various membranes with different characteristics made
different chemical substances, were clearly studied. polyvenyldeen fluride
( PVDF ) membrane is the most focused on during the experiences with
different thicknesses and different permeabilities to see the effect of these
variables on the passing vapours and the amount of condensed and
collected water. The rate of the pumped water underneath the cold and hot
water tanks is fully studied, leading to the best flow rate between the two
chambers without causing any obstacles inside the heating chamber of 6
L/min. Therefore, different (locally made) chemical materials were added
to reach the best membrane and enhance its effect, including (PVDF +
graphene) and (PVDF + zeolite nanoparticles (Z)). The obtained results
were in favour of (PVDF + graphene), which achieved the best results
with the highest temperature difference, 6 L/min flow rate, and 0.45 μm
permeability. The final obtained results of all experiments were compared
in addition to changing all the variables, leading to the best operating
circumstances of (PVDF + graphene) membrane, 70 °C temperature and 6
L/min flow rate. With the best achieved result of 13.95 L/hr.m 2 .