ZEOLITES: LIMITATIONS, ADVANTAGES AND DISADVANTAGES

 

ZEOLITES:

Zeolites are naturally occuring hydrated sodium alumino silicate minerals.

LIMITATIONS of Zeolite Process:

  • If the supplied water is turbid, the suspended matter must be removed first by coagulation, filtration, etc. Otherwise, the turbidity will clog the pores of zeolite bed making it inactive.
  • If the water contains coloured ions (Mn2+, Fe2+), these ions should be removed first because these ions produce manganese and iron zeolite, which cannot be regenerated.
  • If any mineral acid present in the water, it will destroy the zeolite bed, therefore it is neutralised first with soda (Na2CO3).

ADVANTAGES of Zeolite Process:

  • Water quality of below 5 ppm hardness is obtained.
  • This equipment is compact and occupies small space.
  • It requires less time for softening. 
  • It requires less skill for maintenance and operation.
  • No sludge is formed during this process.
  • Its operation is also easy.

DISADVANTAGES of Zeolite Process:

  • This process cannot be used for turbid and acidic water as they will destroy the zeolite bed.
  • This treatment replaces only cations leaving all the anions in the soft water.
  • The zeolite process cannot be used for softening brackish water because brackish water also contains Na+ ions. So the ion exchange reaction will not take place.


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