| Summary: | 碩士 === 中國文化大學 === 應用化學研究所 === 86 === Abstract The secondary coolant system of
nuclear pressurizedwater reactor(PWR) includes the following
subsystems or components:steam generator(SG), main steam line(
MSL),high pressure turbine(HPTB), moisture separator reheater(
MSR), low pressure turbine(LPTB) and condensed water system(
CWS), condensed polisher dimineralizer, feed water system (FWS)
etc. From MSL to turbine, there are steam/liquid coexisted
regions; the other subsystems belong to single liquid phase.
The water treatment or water chemistry control of PWR secondary
coolant system additional with ammonia and hydrazine for all
volatile treatment, since 1970 thismethod had been emphasis for
most PWRs all over the world. This treatment indicates that
injection of ammonia and hydrazine before final feed water
keeping the pH(25℃) in the range of 8.8~10.0(the lower range
8.8~9.2 for the copper containing plants; the higher range
9.2~10.0 for the ferrous containing plants). However, owing to
the higher volatility of ammonia in the steam/liquid coexisted
regions causes the pH ofliquid phase decreased to lower Value
where local corrosion mainly erosion-corrosion happened.
Therey,the new concept of adopting the alkanolamines having the
property "Basicity in higher and volatility in lower than of
ammonia" instead of ammonia as water treatment reagents after
1990. This concept is expected to get the optional condition
for secondary water chemistry of PWR. In this thesis, four
alkanolamines including ethanolamine(ETA), morpholine(MH),
3-methoxyl propylamine(MPA), 2-ammino-2-methylpropylamine (AMP)
were selected for the study of reacting with nuclear grade ion
exchange resins(Dowex, Amberlite, Purolite, Ionac) that expect
to find out the best amine having the lowest selectivity
coefficient with ion exchan resins i.e. lowest consumption may
achieve good cost/benefit effect. The study of volatility in
the secondary water condition at 300℃,1400psig was performed
also that expects to find out the best amine having the lowest
volatility. The conclusion results of these studies were that
the best potential alkanolaminewere ETA and MH. The analytical
methods for alkanolamine were investigated. It was found that
the ion chromatography(IC) and total organic carbon
determination(TOC) were the advanced handling, availiable
methods.Keywords: alkanolamines, ion exchange resins,
volatility, total organic carbon, ion chromatography.
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