Determining wasted energy due to blowing traps

Alaska Joe

This past week my employer allowed me to proceed with a trap maintenance program, (a program the Corporation has never established in its 50+ years), it's been amazing! My superiors think that damage and a lack of heat in structures may be now occuring because, my work has created a situation where big plumes of steam are no longer rocketing from vents throughout the property, as they have been blowing for years. When I stated to them them that plumes were an indication of problems, and they're now gone because of my work, I was told,"Well it's been an unusually warm winter, that's why the plumes went away!" I tried to explain that a blowing trap doesn't know how cold it is outside, to no avail. ANYWAYS, this week I repaired and or replaced 45(rebuilt/upgraded/corrected the install) F&T traps, (30#, 3/4") that were blowing. 22 more were actually still functioning after a dozen years of neglect, a half dozen 70# traps were removed (imploded floats) and replaced with thirty pounders. How can I compute the 45 blowing traps into a savings?

Doug Wagoner

Finding Money

Joe, you wont have to compute. With that many traps blowing the money will show up in the accounting office on the fuel line next month. See if someone in accounting will give you the fuel cost from last year. Compare the cost after the traps have been repaired and maintained for a year. The money will be there. I use to make a game of trying to pay my yearly salary with the savings from various maintenance activities I am in charge of; but after 15 years I have run out and am just trying to maintain status quo. But don't think accounting didn't notice and so did the company president.

Ken_3

Trap Savings

Send me the trap orifice size, System steam pressure, and the cost of an MCF or CCF of gas and i can give you a ballpark savings.

Jerry Boulanger

Bell & Gossett's software

ESP Plus has a calculator in it for estimating the losses through failed traps. Call your local B & G rep and see if you can get a copy.

Joe Lambert

Steam Through Blowing Traps

I have spent much time on this subject. There is no exact way to determine this, because there is always also condensate in the line, and some traps have anular orifice that restrict a gas flow. HOWEVER...

A rule of thumb that provides a conservative steam loss is to take 10% of the rated flow through the trap at your actual pressure at the trap (get this from the catalog cut-sheet)

Unknown

Computing losses

The best way to compte lost steam is a barrel test. Typically what happens is you collect all the wasted steam as condensate and weight it. Each pound of water equals one pound of steam lost.

Assume you collected 1000 pounds of water a day that means that an additional 100 pounds of water entered the system and that that has to be heated up to steam temperature too.

The actual losses work look this.

1000 pounds of steam a day lost

1000 pounds of new water that has to be heated

1000 divided by 8.33 equals water that you need to pay for

1000 pounds of water that registers on the building water meter, you pay for sewage disposal

How many boiler tubes were replaced in the boilers
If you have a chemical treatment program how much extra chemical had to be used

All kidding aside a barrel test is a bit much .

Is there a water meter supplying water to the boilers?

If there is and a log is kept on the water usage the savings can be calculated fairly accurately.

If the meter reads in gallons, convert to pounds of water.

Each pound of water that has to heated to steam at 5 psig has an btu input of about 1150 BTUH.

If you lost a 1000 lbs of water a day that translates to 1,312,000 BTU times 2= 2,624,000 BTUS or about 18+gallons of oil a day.

Do not forget all the other listed items.

I donot know how large your buildings are so the I gave the easiest example possible.

Jake

[Deleted User]

man your boss

sounds like an idiot.

Tony Conner

I'd Recommend Using...

...Joe Lambert's method - it's as good as any. There's really no way to definatively calculate this, but that knife cuts both ways. If you get challenged on your number, just ask "Well, what do YOU think it is?" This is usually answered by varing degrees of sputtering and stuttering. If someone does actually give you a number (this is highly unlikely), and it's very different from yours, just ask how they calculated it. This is normally answered by even MORE sputtering and stuttering

You saved these people a lot of money, and there will be things working now that haven't worked properly in years. And you now have a handy way to check if there are traps blowing through - you can just look at the vents. You'll know about how much of a plume you normally see, and if it gets bigger, start checking the traps that dump into it. You still need to actually check the trap function to make sure it's not failed shut, but unless it's a drip trap, you'll know because somebody will be complaining that either their process isn't working right, or they're cold.