Desalination apparatus and method of desalination

A desalination apparatus is one equipped with multiple-effect evaporation unit; multiple heat-transfer pipes; a scale component removing means for removing at least portion of the scale component in raw water to thereby produce descaled water; mixed water feeding means for feeding a mixed water consisting of a mixture of raw water and descaled water as a water to be treated to the heat transfer tube of each of the evaporators of the first evaporator group disposed on the most anterior stage side among the multiple evaporator groups; and dilution water feeding means for feeding a dilution water consisting of a mixture of concentrated water and mixed water as a water to be treated to the heat transfer tube of each of the evaporators of the second evaporator group disposed on one low temperature side among the first evaporator group.