Sulfides “Re-appearing” After G.A.C. Towers?
asked 29 August 2017 asked by Novaangle18 (390 points)
Hi First of all, I would use the GAC towers in series. Much more efficient with respect to effluent quality as you can load the carbon in the first fitler to a maximum. Check if the sulfides is not orginating from the GAC? It could be of low quality, contaminated...etc. From here it looks like the sulfides are originating from the GAC. Take several samples, chrush the activated carbon to a fine powder, and stirr it overnight. Measure the sulfides concentration in the aqueous phase. Use double distilled water (or at least a water source which is free of sulfides) and check the sulfide concentration before adding the crushed GAC. Finally, before starting, make sure that you are using correctly your sulfides measuring kit and for interferences...one never knows :-)
Is it possible that your reaction time is not long enough, or that you have more naturally occurring iron than you are accounting for in your titration and it's killing the peroxide ? Possibly there is some other solvent in the water that the GAC isn't effectively removing. I agree with the above statement that series is the way to go Best of luck