Pressurized Water Reactors
Pressurized Water Reactors
(OP)
I do not work in the nuclear industry. However, I work with a district heating system that uses pressurized hot water. I would like to know if there is a similar experience base in the two industries. Specifically, in a typical district heating system, one might be dealing with 380 F pressurized water at an operating pressure of about 265 psi. In the nuclear industry, are pressures and temperatures much higher?





RE: Pressurized Water Reactors
RE: Pressurized Water Reactors
The district heating system where I work handles thermal expansion and contraction with an expansion tank that is pressurized by nitrogen. Level control in the tank is accomplished by sensing both liquid level and pressure. I have heard that in at least some nuclear plants, liquid expansion is handled by pressurization of an expansion vessel with steam, and that water sprays are used to modulate steam conditions, thus accomodating the expansion.
I thought that subsystems in a nuclear power plant might use the same type of expansion control that we use, and that it might be worthwhile to exchange operating experience. Our system was designed by Black & Veatch in Kansas City, and I feel that the overall design is excellent.
RE: Pressurized Water Reactors
RE: Pressurized Water Reactors
Most likely, the reason the control sys takes input from both the press and level trans is because as level increases or decreases, you don't want your process filled with N2 and you don't want water backflowing into your nitrogen system.
In a PWR nuc, the pressurizer is also uesd for pressure control and as an expansion tank but uses water and heaters to control press as level changes. Also due to the temp and rad flux in a nuc plant, N2 would not be a good thing to put in your water. Besides chem reactions with the reg water chem you probably would form nitric acid or some other chem just from the heat and rad field which would not be good for plant equip life.
eugene.decker@srs.gov
RE: Pressurized Water Reactors
Coal fired plants that can also operate at very high tempeartures & pressures may have conditions more similar to the water plant described in the inquiry. Might want to inquire among fossil plant engineers & chemists for info.
RE: Pressurized Water Reactors
RE: Pressurized Water Reactors