steam canning

billygoat22

salesguy at work wants me to go with him to look at a steam system for cannery.



supposed to be a 15 lb system w/ regulators at each kettle. they want to replace the steam lines in the place. Its a "washdown" setting so there's no insulation on the pipes now. 



Looking to read up on this type system in case can make any improvements while changing out the piping.  Want to insulate if can, and check on steam trap sizing when there.   



Since its 15 lb, I assume there's a condensate pump on the boiler. In one of the books I got here off the site, systems like this in a dry cleaners tend to eat pumps?



Any recommendations?not too much new steam stuff going on down here in the south. Thanks

Steamhead

You may encounter "flash steam"

when condensate that is not hot enough to boil at 15 pounds is discharged into atmospheric pressure. The lower pressure makes it re-boil, or "flash" back into steam. This is very hard on pumps, and since the flash steam is often wasted, jacks up their energy consumption.



The cure is a "flash tank" which, if you do it right, can be used to direct the heat to a secondary use such as heating water.

billygoat22

repl

thanks, steamhead. 

was doing some reading and came across the flashtank idea, also, the steam kettles are called "retorts" 



it seems you manually vent them at a higher steam pressure to ensure no air in the machine, since air won't heat the tops of the cans. them it heats the cans by regulating the supply pressure to the retort. 



other than that, couldn't find any pipng info on them. 

billygoat22

saw the system

went to the place the other day.



has 90# off boiler, and reducers to 15 and 40# lines. open tank for the return line. feeds back into boiler on pump run off water level control.  



they had 7 40# steam kettles, three retorts, two modine heaters and a blancher.



I recommended calling hoffman or an engineer to draw up a system since new stuff is being added during the repipe.  Hard to size when you don't know the lb/hr rate on each appliance. Know any good designers in central Va?

Brad White

Medium and High Pressure

I am not sure what the code is in VA, but I suspect given pressures over 15 psig and it being a commercial venture, you may need a licensed Professional Engineer to design it and stamp it.



Depending on the load and rapidity of demand, you may be looking at a steam generator or process boiler.



As for designers/engineers in your area, I would ask the facilities department of a local hospital (who are likely to know high pressure steam themselves) or of a university, to find out what engineers they use. If they have an engineer they like, they will be happy to recommend them, I bet.



The hard part of any project like this is gathering information, the steam rate in pounds per hour at what pressure, the ranges, all that.



One set of books I use is from Spirax-Sarco called "Hook-Ups".



http://www.spiraxsarco.com/us/pdfs/training/hookup.pdf



It is available on line for the downloading per the link above, but it also is available from your Spirax-Sarco representative, free last time I checked. There is another book on Steam Utilization, both very handy for your own information.

billygoat22

cool

that's a good pdf there, thanks.  saw a few things just glancing through that may need to be changed. 



the relief valves don't have drainage on the outlet side on the one. bypasses on the regulators setups may be in question now, too.



like the idea to check w/ other facilities.

Brad White

Relief Valve Discharge

Piping the relief valve discharge to a safe place is a low-cost and quick task. It is cheaper than skin grafts and hurts less too.



Seems I made more work for you, but in the end, with diligence and always leaving the in-box of information "open and asking", you will do the final system justice.



Keep us posted on your progress?

billygoat22

-

checked in the other day on the call- sales guy said they're going to let that one go- it'll take up too much labor during one of the busiest times of the year. seemed like an interesting job, though. thanks for the help.