We have a brackish water RO plant with its reject stream having 30000 ppm of TDS. Mechanical Spray Evaporation Pond is now being proposed to concentrate the brine before it is sent to Crystallizer. The point is - till what concentration the brine needs to be concentrated without having any pumping problems? My concern is, if we allow it to reach typical NaCl saturation concentration in sea water - about 26%, lower soluble salts like calcium and magnesium salts will have reached their saturation levels and forms crystals which may pose probelm for pumps and spray nozzles.

Anyone has any experince (Design/Operation) in this earlier? Thnaks in advance for sharing.

The answer to your question will be site specific and will vary with the water quality. You may also have a particulat water quality parameter that is peculiar to the site that will cause problems.

You may also have problems with scaling before the salt concentration reaches that of the sea.

I have looked into the use of spray ponds. Unless your project is an a very arid region, spray ponds are not very practical.