Concentration of Salt Stream 2

[Volunteer]

I am looking for a recommendation to concentrate a liquid stream with the following characteristics:

Sodium Chloride 10-25%
Sodium Sulfate 1 - 5%
Sodium Sulfite 1%
Sodium Phosphate 5%
Sodium Bromide .5%

Currently, it is shipped offsite via a waste hauler to the tune of 4-6 tanker trucks per week. Cost about $350K/year. I want to look at the economics of evaporation / drying and dealing with a concentrated slurry or cake. Flow is 5,000 gal/day, 5 day/week.

Maybe you have an idea, or even a piece of equipment that would work well.

 

[buzzie]

I have installed several 3-5 gpm calandria type crystallizers that take very similar streams to dryness for disposal. Crystallized mixed salts would be directed to a small pressure filter providing a salt cake with 5-15% moisture. Only question I might have is the presence of the sulfite as it may affect filterability - but not sure without checking further. Due to nature of corrosive brine crystallizer metalurgy requires Ti heat exchange surfaces and high (super) grade stainless for vessel construction. My first guess at installed cost should provide payback in 18 months or less. Need 30 psig steam or so to drive crystallizer. If you are interested I can provide you a contact of a previous employer that provides such equipment.

Regards

 

[saxon]

Volunteer, You may want to take a look into Ultra-filtration/RO. Based on your flow rate, you're only looking at approx. 3.5 gpm which is well into the range of smaller UF/RO units. As for crystallizers, this is awful far down in their operating range.

Hope this helps.
saxon

 

[cub3bead]

The 10-25% NaCl will kill RO as a means of concentrating this waste; the osmotic pressure will be too great to realize any significant concentration increases.

A small crytallizer is the way to go for this application.

 

[TrevorP]

Depending on where you are in the world, i.e. how temperate the climate is and how expensive land is, you could try digging a large lined shallow pit. It might seem a bit off the wall, but I've seen this used for extracting salt from sea water, the composition of which will not be too different from what you're talking about (though less concentrated!). You let the sun do the work, hope it doesn't rain, then dig it out! There's nothing you've told us about that sounds too hazardous to allow you to do this.

 

[usdesal]

Buzzie,

How do I contact you for the recommendation on your previous employer for calandria type crystallizer equipment?

usdesal

 

[bimr]

You should contact the RCC division of ionics for this equipment.

http://www.ionics.com/technologies/brineconc/

 

[buzzie]

usdesal,

bimr reference to Ionics RCC is correct. Note that Ionics was recently absorbed into GE Infrastruture but web addresses have not changed yet. RCC phone in Seattle is 425.828.2400.
Regards

 

[bewdley]

I believe the RO way worth to investigate, but I suspect the liquor too strong to be treated.
FYI, a concentrator/crystallizer to bring such a liquor to solid state should cost some 750K, installed, and would use some 300 kg/h of live steam at 6 bar or more. 6 m x 4 at base, some 13 m high.
Product would be something like a 90 % s. s. cake, probably from a filter press. Condensate could be recovered as good water (say, 50 ppm tds max.)