For drain water, how to differentiate the sources of the alkaline drain water, between cement & caustic soda?
The pH for drain water sample at my place is high,>11, we assume the sources is from cement because the construction site is nearby. But now, the construction is finished and they have clean the drain, but the pH is still high, and maybe it’s from other sources, maybe caustic soda because nearby have waste water treatment plant, the plant use caustic soda. So, now, how I want to know which sources? Is there any lab method can differentiate it?
December 12, 2011 @ 1:52 pm
well PH of 11 is not natural. most probably the treatment facility has caused such drastic change in your water, you can ask the local authority to conduct a random test and to check whether the waste treatment plant passed the maximum Ph requirement of their water discharge.
December 12, 2011 @ 2:25 pm
Don’t let the construction site off the hook just yet. Any water passing through any concrete powder or waste may still be contaminated and result in a high pH. It’s possible that there is/was a pile of concrete that was dumped, buried and rain water percolating through it is becoming basic and polluting the water in the drainage line.
December 12, 2011 @ 3:03 pm
Cement will continue to cure and release alkaline substances for some time, so you shouldn’t totally discount that, yet. However, a pH of 11 is very alkaline and a possible cause would be NaOH. Have a lab run a test for calcium and/or sodium. Cement is primarily a calcium compound, caustic soda is based on sodium. That should help to distinguish the potential sources.
RSS feed for comments on this post. TrackBack URL
Leave a comment