Methods of water desalination and using water as source of renewable energy

الملخص EN

As it is known, the water resource can be classified as one of the sources of renewable energy; that is being renewed and never vanishes until specific time.

For example, Ocean water and the water from the deep wells are expected last for a long time into the future and it is difficult for anyone to predict the disappearing time of these resources.

This fact opens ways to the industries that depend on renewable energy such as electricity, and it is considered that this industry is the important for humans.

Generation of electricity using renewable energy reduces the cost of raw materials dramatically.

There are two famous methods to produce electricity by using water; the first one is water turbine and the second one is steam turbine.

Though this paper outlines specific details about the principle of operation of the water turbine, the main idea is to rotate the blades that are fixed at the end of shaft by using water energy.

When the amount of water pass through these blades, the acceleration rotates the shaft to generate magnetic field due to flux magnetic and produces electricity.

There are some accessories that should be connected to control speed of turbine shaft, because the high speed generates huge electric power that leads to side effects such as damage of mechanical parts and high temperature.

Furthermore, this paper focuses on water desalination by using reverse osmosis method to get dam water to use in industrial field.

The water treatment unit is chosen as the case study at Asphalt Benghazi plant and this paper illustrates steps to treat water from well to RO.

It is observed that the design capacity reaches 350m /day of dam water whose source is from the well.

With respect to the Mediterranean Sea, the properties such as the contents of total dissolved solid "TDS" peaked up to a high amount of 63500 ppm.

This salty water passes through two reverse osmosis stages to produce dam water amounted to 2.54 ppm and this amount of dam water is fed to two boilers to produce 14 ton / hr of steam this water to produce about 14 ton/h.

In addition, the study focused on the process of using dam water or well water to rotate blades of water turbine while transferring water to product tank and then at least to the electrical source to feed water treatment unit by electricity.

As it is known, for the water plant that depends on reverse osmosis, the consumption power is very high, and costs of production increases incredibly.

Hence this case study focusses on how to raise the production and keep the consumption power at low level by using renewable energy.

In addition, attempts were made to recycle some amount of water discharged from the Benghazi Asphalt plant to reduce the working hours of water treatment unit.

For example, blow down for boilers and the amount of water rejected from cooling tower might be sufficient to make boilers run for few more hours.