high pressure + high TDS = corossion ?

[TominTunis]

Hi folks,
Given:
Pumping water
TDH - 286 m
flow - 300 lps
water quality (concentration of dissolved solids - high)
ph - ?
concentration of CO2 - ?
temp - 18 - 28C
pipe material - concrete lined DI

Wanted:
rate at which my pipes are going to lose cross sectional area

Have any of you done such a calculation, or can you indicate a reference. I checked AWWA and a 2010 pump handbook and have come here next. By the way, it's a site in East Africa. Thx.

 

[BigInch]

Since the solids are dissolved, there will not be any mechanical abrasion and it should be more a function of fluid velocity than anything, discounting corrosion at least until you know the PH.

Generally velocities below 10 fps will be on the safe side of erosion limits and erosion rates would normally not even need to be calculated.

Velocities much higher than that for pipelines of any significant length may have too much of a power cost to be economical anyway.

 

[vpl]

I'd also try to keep velocities above 3 feet per second to avoid settling and any possible microbiologically induced corrosion.



Patricia Lougheed

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[TominTunis]

I think i was misleading and should have said "high pressure + high TDS = calcification".

if my first year chemistry comes back to life, i recall that under increasing pressure dissolved calcium products precipitate out of solution. i have a groundwater with high concentration of calcium products and want to see at what concentration and duration the calcification of the pipe becomes too costly.