Hot well volume

[Lopez Mike]

I've been struggling with the search function to no avail so I'll just open up a topic.

I'm going to build a new hot well (or hotwell if you like). With my failure to be able to search the forum, I'll put it out for discussion.

The only consideration that comes to mind for sizing said well would be how rapidly the level responds to flow variations. Too narrow and the float valve might have to be opening and closing too often. That, of course, assumes that the valve has some hysteresis. If not, even then, if there was to be some malfunction in the system, the well might overflow before I have to react.

I loath any unnecessary need for any quick reaction to power plant regulation (else why would I have a float valve!). So given the flow rate through the condenser, any thoughts as to well volume? Or any decent guesses as to the volume given other specs like boiler water volume or engine specs.

Of course, any advice to why the search engine is upset by the notion of a hot well or hotwell will gratefully accepted!

Mike

[TahoeSteam]

Hi Mike,

If you have the room for it, I would think something close to at least half the capacity of your boiler will allow for some settling and filtration. Could also help reduce some panic, and allow for some time to get to safety if you have an unforeseen condensate recovery problem.

On the ' George H. Sandin' we have about 10 gallons capacity for a Semple VFT. 'Wayward Belle' has 2 gallons for about 1/2 gallon capacity mono tube. 'Persistance' has 30 gallons for our 30 gallon capacity boiler (admittedly there's a bit more space on 'Persistance'). 'Ben My Chree' will have about 10 gallons for the Mentzer 40sqft watertube.

Hope that's of some help.

How's the trailer and boat rebuild/repair coming along?

[PeteThePen1]

Hi Mike and Friends

I a not able to offer anything useful in answer to the technical question, since for the current project the hotwell is based on a bain marie 'basin' that I picked up free from the local Dump.

However, in relation to the search function, one can persuade it to do things by 'cheating' it. Searching for Hotwell just gets rejected as too common a term, but I tried 'Columnar Hotwell' and got 338 results. I put that in as I has a fuzzy memory of one of our corespondents posting a picture of a very well engineered square section but very tall hotwell. Sadly that did not come up, but there was some interesting stuff in the other answers.

All good wishes for the Festive Season from a very damp Cymru.

Pete

[fredrosse]

In large utility power plant practice, the hotwell storage volume is typically 3 minutes storage volume at maximum power. That is USA practice, and generally in Canada 5 to 8 minutes storage is typical.

For our steamboats, where feedwater flow at full load is around 100 PPH (Pounds Per Hour), a six minute storage would be 10 pounds of water, or about 1-1/4 US gallons. Depending on the size of the steam plant, these numbers can be adjusted accordingly.

[Lopez Mike]

Thanks to all for your advice and help.

As too the problems I was having with the search engine, Simon has most graciously changed the search engine parameters such that it will accept pretty much anything!

As to the hot well subject, I find that the various methods seem to converge. And for no particular reason. Hmm.

One way is to use reaction time. How much time to disaster. Another is to sort of average out what has worked in the past. I call this the statistical method. Yet another is to design around how rapidly the well level will react to load changes based on the surface areas of the well and boiler (My contribution).

No serious calculations to back all of this up but I seem to be coming up with a 4 to 1 ratio whether it be surface area or volume.

Over thinking this all as usual. Since I plan on building this new well out of plywood and epoxy, I think I'll just build to suit convenience and build another if needed.

What I thought was the sound of nesting turns out to be the wrapping of presents. Time to flee to the hills on my dirt bike! Wintering in Baja has its up sides.

Mike