3 replies to this topic

[cwca81]

we are correcting elevated pH water from a construction related project site. We are using diluted sulfuric acid at 36% and injecting it into a pvc pipe of flowing water. Do I need to be concerned about the exothermic heat produced using the diluted concentration? And other considerations do I need to think about? Thank you

[breizh]

Hi ,

Attached a document about H2SO4 .
Hope it helps

Breizh

[siretb]

36%wt is already diluted, and the amount you'll need will be small, compared to the flow of water.
I think you need not worry about temperature elevation.
I'd pay more care about the whole process control chain, including the probe and the response times, specially if you plan to correct pH with only one injection point.
I like a feedforward / feedback approach , where the acid flowrate is first calculated according to the water flowrate, and adjusted by a feedback (probe located in a small holdup tank).
Unless your water flowrate is very steady, it may be difficult to control the pH with a simple feedback loop. You tend to have big upsets when the flowrate suddenly changes.

[bmk]

[quote name='cwca81' date='18 May 2010 - 12:00 AM' timestamp='1274159450' post='39080']
we are correcting elevated pH water from a construction related project site. We are using diluted sulfuric acid at 36% and injecting it into a pvc pipe of flowing water. Do I need to be concerned about the exothermic heat produced using the diluted concentration? And other considerations do I need to think about? Thank you
[name=b.m.khare may,17,2010.]
The heat of neutralization will cause a rise in water temperature and this is harmless. If you reduce conc.of sulfuric acid to 10 % it will be better. This will ensure that you are not making water acidic rather than neutral. In addition, try to create turbulence at the point of addition for rapid mixing and dissipation of heat by inserting baffles in the flow pipe.