Ask Your Boiler and System Questions or Leave Your Comments Here
Steaming crabs
Caution: All drawings are conceptual drawings for illustration purposes only and may be incomplete.In the coastal areas of the Chesapeake Bay and inland waterways, the steaming and selling of crabs is a business, as is a lot of other coastal areas. There is nothing like a good steaming hot Maryland Blue crab. The question is often asked about how to pipe steam boilers for the steaming of these scrumptious crustaceans. There are many ways to pipe the boilers, but here is one of the best piping diagrams I have come across. It came from an old friend, Owen Hartlove, in Baltimore.
We all know that when it comes to using a steam boiler for anything other than steam heating, the condensate gets put down the drain. That means we add a substantial amount of fresh water, which significantly reduces the boiler's life expectancy. I have a list below of what should be done from sizing to piping, which has given us the longest life from a steam boiler than any other diagram I have seen. The original installation may be more expensive, but it works better and lasts longer, making it worth the investment to do a better job up front and save money overall. This gives us the driest steam for better-tasting crabs. Remember, our installations affect the crab's taste and the success of our customers.
1. Calculate 32,000 BTUs or 133.3 sq. ft. per bushel of crabs
If you have 5 - 2 bushel pots, the boiler requirement is 320,000 BTU's net output or 1333 sq ft of steam
2. Preheat feed water through the domestic hot water coil or preferably from a water heater
Adding hot water will get rid of oxygen and dissolved solids before entering the boiler.
I would rather do this from a water heater than a domestic hot water coil in the boiler.
As cold water would be drawn through the coil, it would kill most of the steam in the Boiler.
3. Install at least two boiler risers from the boiler. Make the header as high as possible or use a dropped header on the boiler and system header.
4. Use as high a riser as possible off crab pot
4. Insulate all piping
5. Keep header velocity below 25 fps
6. Keep system piping velocity below 50 feet per second
7. Clean the boiler well by heating it and skimmingthe boiler very well, do not add chemicals.
8. Use a fast feeder for each boiler. Most electronic feeders feed too slowly. Consider an MM 101 feeder.
9. Two boilers are more efficient than one as the steaming load changes constantly.
FT Traps are only required when you have more than one boiler.
Disclaimer: The information found on this website is for informational purposes only. All preventive maintenance, service, and installations should be reviewed on a per-job basis. Any work on your heating system should be performed only by qualified, experienced personnel. Comfort-Calc or its personnel accepts no responsibility for improper information, application, damage to property, or bodily injury from applied information found on this website.