Saltwater Corrosion on Pipes 4

[cobaltman]

For a Chemical Engineer -

Project: Building a saltwater distribution lake in the mountains for fighting fires, such as the fires in California.
Water source is seawater to be piped into mountain lakes. Need to know what type of pipes will resist salt water corrosion. Thanks for your reply.

 

[SJones]

thread723-249509

Steve Jones
Materials & Corrosion Engineer

http://www.linkedin.com/pub/8/83b/b04

 

[BigInch]

The problem is likely to be a material required for corrosion resistance for long term exposure to salt water being a total waste of expensive corrosion resistant properties, but while not actually doing something you need to be doing, like pumping water. It would also be nice to find some other use for the pipes when not being used for salt water distribution, such as irrigation etc. That may be dreaming, but it might help the funding of such facilities too. Think about it.

I'd also consider a cheaper carbon steel material, perhaps lined, or carbon steel pipe and using an environmentally friendly corrosion inhibitor during layup, or a combination of flushing and filling with fresh water and/ or a bit of inhibitor too, for adding to the pipe contents after you have distributed and stored all the salt water you need for fire fighting purposes.

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[BigInch]

Look specifically at Driscopipe and HDPEs suitable for higher pressures you may experience in mountainous terrain.

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[MJCronin]

Forget the salt water and the expensive corrosion resistant coatings and materials....

The fire fighters will ruin thier equipment after the first use

Why don't you, over time, gather the little bit of rainwater available, put a cover on the pond/container and use that ?

Saltwater is, in the long term, expensive...

 

[BigInch]

excellent point although for some reason salt water seems to be somewhat suitable for firefighting aircraft.

**********************
"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[StoneCold]

You can't pump seawater into mountain lakes. You will kill the aquatic life in the lakes. You could make your own holding ponds filled with sea water but if it is stagnant it is going to begin stinking badly real fast.


regards
StoneCold

 

[ApC2Kp]

cobaltman,

The small to medium size Nps-24 pipe lines for saltwater service could be in ductile iron material.

Some coastal cities have seawater piped in DIron to the fire hydrants and the seawater also used for street washing.

The entry level piping material for shipboard desalination units would be ductile iron. The Navy has a different situation on their submarines, and uses titanium for those desalination units. It is a matter of how much maintenance is needed and how much down time is acceptable for repair. The seawater materials of construction range upward to naval bronze, Cu-Ni, nickel alloys AL6XN, Hastelloy, etc. depending on temperature requirements.

Power plants at coastal locations use ductile iron pipe, or now use fiberglass pipe for cooling by seawater. Some larger diameter Nps-36+ use rubber lined steel pipe, but must deal with lining failures and eventual replacement.

Most underground mains are still ductile iron pipe, but the residential distribution potable water supply piping is now PVC or HDPE plastic piping. These could also handle seawater, as BigInch suggested. It will depend on pipe size, pressure, and length of line as to the economical choice.

Recycled water or effluent from waste water treatment plants might be more environmentally acceptable for storage lakes, as compared to seawater.