New Orleans Pumps 2

[unclesyd]

I caught the tail end of an interview where it was mentioned that the electric motors that run the drainage pumps are 50 cycle and they have to have a special power plant up and running. I have a lot of information on the drainage system but no mention of the type motors except that the last pump installed had a synchronous motor.
I was just wandering if this true.

This is curious as my home near coal and ore mines and steel mills had a lot of 50 cycle equipment. In fact the company towns around the mines and mills had 50 cycle power, free, so everything electrical had to came from the company store.

 

[rmw]

Unclesyd,

You bet me to the punch on this one. I was going to post a thread today asking a related question.

When I was just a pup of an engineer, I was a service engineer for a major turbine OEM, and while I never visited the stations I will mention, I did have co-service entineers who had describe them to me.

The question I was going to post pertained to seeing if this was still the case, since it has been 30+ years ago that I gleaned this information, and the stations were old at the time. They were said to be 1920 vintage stuff.

The pumps that drained the city of NO of that day were part of an entity known as Sewage and Water Board, and were driven by 25 cycle motors which had their own 25 cycle generator at a power station devoted to that application. (Yes, I am that old, and I do know that it is hertz now, I just don't think that way.)

Again, depending on my older memory, as I do remember it, it was stated that this was all used stuff brought in from way up north somewhere, Detroit as I remember it, and it was obsolete equipment wherever it came from. Some how the whole 25 cycle set up; generators and pumps and motors came in under that umbrella.

So, my question was going to be: (recognizing that anyone who might be able to answer it is probably not on line right now-dealing with their own particular personal or professional tradedy) were the old S&WB 25 cycle pumps/generators of the 1970's still in place, or had they been upgraded to something more modern.

Would a 25 cycle motor be upgradable to a 50 hertz application or is the 50 hertz statement just a typical news media situation of getting technical information botched up as they broad cast it. If it is still 25 cycle, they probably had never heard of that.

As I have been watching all this, I have been wondering about the S&WB situation, and how they were going about doing what they do. I shudder to think that they will have to be trying to start up 80 year old boilers. But, I note that Entergy, the power company in the area (NOPSI is part of Entergy) returned some late '40's vintage units to service several years ago at their patterson station, as well as some other old boat anchor stations throughout their system. (We ratepayers paid for it all.)

If anybody has any updated information about the pump situation in NO, at least Unclesyd and I are intereested.

rmw

 

[rmw]

And, of course, any sites that google finds that might have information are off line (possibly flooded) right now.

rmw

 

[itsmoked]

Speaking of poor New Orleans, what about all those sub(marine)stations. Are those big pad mounted oil filled xfmrs vented? Hence now water polluted? Or do they just pressure wash them and wait for them to dry?

 

[dpc]

The 25 Hz system was still in operation in the mid-1980s. At that time they were looking at converting over to 60 Hz as part of a major upgrade. I believe that this was done, but I'm not sure. The Board indeed had it own power plants and power distribution system and I believe they planned to do the same for the 60 Hz system, but with provisions for interconnection with the grid for backup.

I really doubt that they converted 25 Hz to 50 Hz.

The transformers generally have relief valves. If they are submerged, they can probably be salvaged if they are cleaned off and dried out (after re-filling probably).

It's a huge mess, but one that everyone knew was possible, so the lack of preparedness surprises me a little (but it probably shouldn't).

 

[unclesyd]

SlideRuleEra has posted a link to the history of these pumps in thread769-133181.

Also ASME has an article on the pumps.

http://www.asme.org/history/brochures/h003.pdf

 

[davidinindy]

I think a bigger question, perhaps not for this forum, would be "Who decided it would be a good idea to build a city below sea level, surrounded by water?"
Not that I don't have sympathy. I truly am sorry and saddened by the scenes unfolding on the news, but it seems like this catastrophe was inevidable.

David

 

[itsmoked]

Even worse... Can they/should they rebuild in such a spot.

 

[unclesyd]

You have a bigger problem if you want to restrict building along the coast. If you take out NO you would then have to take out all of coastlines from Texas up to NJ if you are trying to eliminate damage caused by a hurricane with the magnitude of Katrina.

Where would you put the ports?
Where would you put the refineries since no one wants them in their backyard?
Where altitude would be the cutoff?
Would we remove San Francisco before the big one or maybe LA?
What about the Washington or Oregon, maybe a Tsunami or volcanic eruption ?

NO has been there for over 300 yrs. Though it has admittedly been over developed which should be corrected. The failure in NO was the engineering in the levees, the pumping system, the electrical system, communications and last but not least p-ss poor planning by the officials. This didn’t fit their models so they have no idea which direction to turn. As stated in another post it is unconscionable that a double general states that we have several plans to plug the levees, but we can’t get to leak. To me it seems that it wasn’t a very good plan. Then someone from COE get up and says that through the efforts of a lot of people the water level has crested. I think the only person who influenced this was fellow by the name of Archimedes. Later newscast showed water still flowing through the 17th St break. I understand that they are trying to shut off the water in the canal from Lake Pontchartrain with sheet piling.
You know they are in deep when the FEMA man includes the press when he says it will take patience while they “think out of the box”.

Another rant by unclesyd

PS:
They waited until the price jump at the pumps to release some oil from the SPR.

 

[dpc]

New Orleans was not always below sea level. It has been sinking for quite a while. NO has a lot of inherent problems - the Mississippi River is trying to change course, being restrained only by the US Army Corps of Engineers (and $$billions in federal tax money)

No one would locate a city where NO is if they were starting from scratch today. It would make a lot of sense to re-build somewhere else. But I suspect the political reality is that it will be re-built and we will all be helping to pay for it.

Since a levee failure and/or a major hurricane have long been known to have major consequences for NO, I am amazed at the apparent complete lack of realistic contingency planning for this event.

I suspect this will be a major turning point in emergency planning and preparedness in the US, at least I hope so. It also provides a reminder of how much we depend on electric power. As emergency batteries run down and emergency generators go under water, NO has essentially no communications with the outside world. Even police radios do not work without their linked repeaters and base stations. And forget about your cell phone for quite a while - although I've heard some landlines were still working at some hotels.

OK - enough off-topic ranting and raving from me.

 

[electricpete]

I couldn't find many links on the subject. Has anyone seen links with good details on the pumping setup and the levees?

Are the pumps motor driven or diesel driven?



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[jraef]

There are a lot of pumps all over the area. Electric motor driven for the most part, but there are a few diesel and natural gas. But even those are not going to work submerged.

I read some great stuff on the pump systems in the past because we bid on some of the upgrade work, but all of the links I kept were from Tulane or Loyola Universities, and sadly right now none of them are working. I fear that much has been lost.

Found some info on the pumps themselves, but not much on the electrical system. I do know they have been doing major upgrades since 2002 at least, but I don't think it was complete. Some of the oldest systems were 25Hz (not 50 AFAIK), because they were begun near the turn of the century. With Westinghouse and Tesla's success in Niagra using a 25Hz alternator system, NO jumped right on the bandwagon and went that route too. The Woods Screw Pump motors were 25Hz because they wanted high efficiency. 25Hz is fairly good for that on motors, but we don't use it because it makes for flickering lights. Most of the oldest have all been upgraded to 60Hz power AFAIK. Knowing the news media, they probably jumped all over the story of the few stations left that had not yet been upgraded because it makes it more sensational, especially if they can hint at some sort of scandal.

Pump info:

http://www.asme.org/history/brochures/h003.pdf

http://www.ittfluidtechnology.com/scripts/news_JeffParish.asp?BT=N

http://www.feedscrews.com/shownews/329

Intersting related NOLA info:

http://margaretsaizan.typepad.com/photos/uncategorized/neworleans5.gif

Check out this eerie blog prediction from 2004!

http://www.freerepublic.com/focus/f-news/1215775/posts

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[rmw]

That explains the "way up north" connection that I had in my mind. After I posted, I remembered that it might be associated with Niagra. I think I remember it being said that some of the equipment currently in service (this was the early '70's) had been relocated from the Niagra projects, not the pumps, but the generators or motors. I do remember the particular electrical engineer who related a lot of that to me talking about the generators, and/or the turbines as that is what we worked on. A 25Hz turbine generator even in 1970 was an odd duck.

rmw

 

[dpc]

I don't think the pumps will help much, even if they can run, until the levees are repaired. Otherwise, anything pumped out will just run back in. I doubt if they could make too much headway against that, although these are very large pumps.

Now that the water levels have equalized, levee repair might go a little better than it has been.

 

[jraef]

I agree. The rumored pumping rate (from that blog link I posted above) seems to be 1-2 inches per day? 20 feet (240") of water then would take 4 months! And that assumes you get them all running at the same time and it never rains, which we know is not going to happen.

I venture to say that most of them will be turned on as soon as they can get them (and their power sources) "somewhat" dry, and whatever damage or contamination they suffered will be left to allow final destruction in short order. The problem will continue for a long time.

Speaking of contamination, I fear that their entire electrical grid will be down a lot longer than the pundits want to admit publicly. That "toxic soup" that is the aftermath of the trapped water is full of chemicals and solvent that were never meant to come in contact with insualting materials. I expect to see some major fireworks when they start to go back on line.

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[TheBlacksmith]

Navy always taught "plug the holes first and then start the pumps"; otherwise you're just moving more water back outside to come back in. Equalization of the water levels (i.e. the city is full) should make it easier to repair the levees.

Blacksmith

 

[electricpete]

With levels equalized there is a relatively little flow through the breach.

With pumps working, the flow rate through the breach would be roughly equal to pumping capacity.

This would provide an erosive force which may further degrade the breach and also interfere with repair efforts. My vote (not that anyone cares) is to leave the pumps off until major breachers are repaired.

Interesting comment about the electrical system jraef. I hadn't thought of that.

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[unclesyd]

TheBlacksmith,
You are correct in that respect if the leak is large as in this case, but I have been in a situation where the pumps kept the engine that was running the pumps from going under water.
They had a catch 22 in this case where as you say if they started the pumps they would be circulation pumps not the dewatering pumps as needed as a number of the pumps discharge into the 17th Street Canal where the major break was.
Just heard a good one. The reason that they couldn’t get to the big break in levee was that a new low bridge that blocked the canal had just opened and they couldn’t remove it.

 

[itsmoked]

From what I have heard there is a large tidal flow which is a problem not usually associated with levy breaches. This will make repairs more dificult than the usual "plow a bunch of dirt into the hole until it's plugged" technic.
Because any fill placed will be washed away. I wonder if they could switch on pumps in sequence to counter the tidal motion. (if they had functional pumps)

 

[unclesyd]

I heard again that the COE was still having trouble getting the Super Sacks of sand to levee as they did have enough slings. This was because they lost a sling every time they dropped a sack. It got the things that the military likes, a squib release if you want it.

I just sent this link to several websites hoping it would get to someone close to the action.

http://www.seacatch.com/index.htm