DM Plant in Coal based power plants - Can it be located outdoors 2

[RRaghunath]

DM plants are part of power plants catering to the water requirements of the steam generator. In India, I have always come across DM plants located indoors.

Any one who has seen the same located outdoors? I think technically the same should pose no problem but am looking for some examples.

Thanks in anticipation.

 

[MikeJefferies]

No reason why they can't be outside, you just need to take extra care over the instrumentation and valves - make sure everything is weather proof. I guess the other issue will be loading / unloading resin in bad weather.

 

[cub3bead]

They have been located outdoors before if you don't have a freezing problem. Outdoor installations do tend to have more problems with the instrumentation and valves. You also have to paint them more frequently.

Biggest potential problem is disbonding of the rubber linings from the steel shell if they are not atleast shaded.

In very hot climates be careful with possible overheating of the anion resins in standby units especially if Type II resin has been used. Strong base functionality will be lsot quickly.

 

[xabproject]

Dear RRN,
One DPR/Feasibility Study/Basic Study done by the erstwhile TCE-Bombay, forgot which office it was, has done a good evaluation of such considerations in respect of a project "Khammam Chemical Refineries" - first being an Outdoor design - later changed to Indoor, all in the context of Coal Fired station. One was that the DM Plant had to be run using a state of the art PLC (dust protection / controlled ambience etc for this PLC demanded a clad building anyway!!) and was to house an elaborate WTP MCC / DM PLANT MCC...Also the assigned "Station Chemist" was a close relative of the big boss ;-)
and ...Interesting fact was there was another DM plant just across the battery limit 1.2 km away vended by same party with very same features and it was outdoor!! The Station Chemist of that Main Process Plant (with higher through put of DM Water though) was not... yes yes you are right ;-)
CEGB Plant layouts also discusses these issues...not exactly all;-)
Can you get hold of any one??

cub3bead's post it quite thrilling!!!

 

[sbush]

I have personal experience with only one plant where the entire process is located outdoors. It is located at a power generating plant on the coast of North Carolina where seasonal temperatures range from -6.6 C to 43.3 C, and there have been at least two hurricanes pass over the plant since the 1990 start-up date. In addition to four treatment vessels, there are electric actuated valves (with small integral heaters) and a PLC-based control panel, blower, and compressor. Only the piping is insulated.

In all this time, there has only been a few control panel problems due to lightning strikes, but they were not catastrophic. All in all, the outdoor environment has not presented any major problems and everyone at the plant is quite satified.

As I said, this is the only completely outdoor system we have experience with. However, there are many more installation where only the pressure vessels are installed outdoors while the face piping, valves, instrumentation and controls are located inside an adjacent building. This method affords the best of both worlds, because the more sensitive components are protected from the elements while the much larger, space consuming, vessels are outside. This can cut down, substantially, on the size of the building required. Painting issues and the effects of warming or cooling on the contents of the vessels can be mitigated by insulating the vessels. Having the vessels outside makes it much easier to access the manways for load media when using a forklift and for personnel entering and exiting the vessel, especially when a tripod setup is necessary for safety and plenty of headroom is required.

S. Bush

http://www.water-eg.com