A study of the transport of activated corrosion products in the heat transport circuit of pressurized water-cooled nuclear reactors using an in-reactor loop showed that the concentration of particulate and dissolved corrosion products in the high-temperature water depends on such chemical parameters as pH and dissolved hydrogen concentration. Transients in these parameters, as well as in temperature, generally increase the concentration of suspended corrosion products. The maximum concentration of particles observed is much reduced when high-flow, high-temperature filtration is used. Filtration also reduces the steady-state concentration of particles. Dissolved corrosion products are mainly responsible for activity accumulation on surfaces. The data obtained from this study were used to estimate the following rate constants for some of the transfer processes involved in the contamination of the primary heat transport circuit in water-cooled nuclear power reactors:

Crud generation rate:2 × 10−8g/m2·s
In-core deposition:(1 to 2) × 10−2 kg/m2·s
In-core release:(1 to 1.8) × 10−6S−1
Out-core contamination:6.4 ×10−3 kg/m2·s
Out-core release:5.2 ×10−8s−1 without filtration, 8.0 × 10−8s−1 with filtration.