N***r
发帖数: 2539 | 1 //////////////////////////////
Sorry I don't have Chinese input here.
I am lack of knowledge of Chemistry....
This question was raised when I read a journal paper, A model of chemistry
and thermal hydraulics in PWR fuel crud deposits, Journal of Nuclear
Materials 353 (2006) 1–11
//////////////////////////////
As a background, in PWR (pressurized water reactor), certain chemistry species are added into the coolant system to control reactivity, pH value, etc. Two common these species are H3BO3 and LiOH, the concentrations of which have orders of magnitude of 1000ppm and 1ppm, respectively.
As time goes by, a porous crud layer from corrosion products (not H3BO3 and LiOH) forms on the fuel caldding surface and these species accumulate in this crud layer so that the concentrations become high. This high concentration depends on how deep it penetrates into the porous crud layer
and their diffusivity, shown in the attached figure. As these concentrations become really high, precipitation may happen, e.g., solid LiBO2 may appear due to the high concentration of Li+ and H3BO3, as shown in the attached figure.
The thing really bothers me is that how come there's a concentration of the solid LiBO2 phase? Does it have anything to do with the balance of the concentration of those species shown in the figure? | N***r
发帖数: 2539 | 2 can someone give a hint?
baozi appreciate
species are added into the coolant system to control reactivity, pH value,
etc. Two common these species are H3BO3 and LiOH, the concentrations of
which have orders of magnitude of 1000ppm and 1ppm, respectively.
and LiOH) forms on the fuel caldding surface and these species accumulate in
this crud layer so that the concentrations become high. This high
concentration depends on how deep it penetrates into the porous crud layer
concentrations become really high, precipitation may happen, e.g., solid
LiBO2 may appear due to the high concentration of Li+ and H3BO3, as shown in
the attached figure.
【在 N***r 的大作中提到】
: //////////////////////////////
: Sorry I don't have Chinese input here.
: I am lack of knowledge of Chemistry....
: This question was raised when I read a journal paper, A model of chemistry
: and thermal hydraulics in PWR fuel crud deposits, Journal of Nuclear
: Materials 353 (2006) 1–11
: //////////////////////////////
: As a background, in PWR (pressurized water reactor), certain chemistry species are added into the coolant system to control reactivity, pH value, etc. Two common these species are H3BO3 and LiOH, the concentrations of which have orders of magnitude of 1000ppm and 1ppm, respectively.
: As time goes by, a porous crud layer from corrosion products (not H3BO3 and LiOH) forms on the fuel caldding surface and these species accumulate in this crud layer so that the concentrations become high. This high concentration depends on how deep it penetrates into the porous crud layer
: and their diffusivity, shown in the attached figure. As these concentrations become really high, precipitation may happen, e.g., solid LiBO2 may appear due to the high concentration of Li+ and H3BO3, as shown in the attached figure.
| s****s
发帖数: 66 | 3 个人猜测啊，不是我的方向呵呵。
就像灰尘飘空中一样，用concentration表示应该没问题吧？
这个沉淀是不是没有聚集起来，只是形成类似浊液的表面层啊？
当然肯定会有一些理由来解释为什么这层浊液能吸附上去啦，就像你说了的那些离子的
存在。
species are added into the coolant system to control reactivity, pH value,
etc. Two common these species are H3BO3 and LiOH, the concentrations of
which have orders of magnitude of 1000ppm and 1ppm, respectively.
and LiOH) forms on the fuel caldding surface and these species accumulate in
this crud layer so that the concentrations become high. This high
concentration depends on how deep it penetrates into the porous crud layer
concentrations become really high, precipitation may happen, e.g., solid
LiBO2 may appear due to the high concentration of Li+ and H3BO3, as shown in
the attached figure.
【在 N***r 的大作中提到】
: //////////////////////////////
: Sorry I don't have Chinese input here.
: I am lack of knowledge of Chemistry....
: This question was raised when I read a journal paper, A model of chemistry
: and thermal hydraulics in PWR fuel crud deposits, Journal of Nuclear
: Materials 353 (2006) 1–11
: //////////////////////////////
: As a background, in PWR (pressurized water reactor), certain chemistry species are added into the coolant system to control reactivity, pH value, etc. Two common these species are H3BO3 and LiOH, the concentrations of which have orders of magnitude of 1000ppm and 1ppm, respectively.
: As time goes by, a porous crud layer from corrosion products (not H3BO3 and LiOH) forms on the fuel caldding surface and these species accumulate in this crud layer so that the concentrations become high. This high concentration depends on how deep it penetrates into the porous crud layer
: and their diffusivity, shown in the attached figure. As these concentrations become really high, precipitation may happen, e.g., solid LiBO2 may appear due to the high concentration of Li+ and H3BO3, as shown in the attached figure.
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