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There are three main problems in MSF :

1- High power consumption, usually MSF needs a power plant to provide the
necessary power.

2- Low efficiency, the maximum efficiency of MSF is around 25%.[9]

3- environmental impact, high GHG emissions.

to solve these problems we will demand solar collectors to provide the required heat
to brine and then circulate it to get higher efficiency to use MSF as the future of
desalination technologies.

2- Multi-effect desalination ( MED):

MED is the development version of MSF. In MSF hot seawater enter the flush vessel
and evaporate due to a pressure drop. In MED cold seawater is sprayed via nozzles
or perforated plates over bundles of heat exchanger pipes in a flush vessel, this
causes to evaporate seawater and the collected like in MSF.

seawater

Fresh water
steam

Figure 2.9 MED single-stage process.
The main difference between the MED and MSF processes is that while vapor is
created in an MSF system through flashing, evaporation of feed water in MED is
achieved through heat transfer from the steam in the condenser tubes into the source
water sprayed onto these tubes. This heat transfer at the same time results in
condensation of the vapor to freshwater.

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