Specialfeatures of operation of the high-temperature filter of the nwt-1

Abstract

The features of operation of the bypass cleaning system of the first circuit coolant (NWT 1), in particular high-temperature mechanical filter with granular loading of titanium crumb are considered. Attention is paid to high mechanical, thermal and chemical resistance. It has been stated that today there is a greater 30 years increase in the use of high-temperature sorbents in terms of positive and negative power, and a constant supply of heat to the temperature of the heating and cooling cycle. It’s not possible to give a viscous mixture to a conglomerate of products in a corroded construction material with a perpetual sorbent, and it is not permissible to add an additional sorbent. More than 30 years of experience in the operation of high temperature sorbents have revealed their positive and negative properties. In particular, the significant effect of the number of cycles of sorption-desorption on the ability of the filter layer of titanium crumb to retain impurities of the coolant. The sufficiently high adhesion strength of the conglomerate of corrosion products of structural materials of the first contour with the sponge sorbent does not allow to fully utilize the advantages of the sorbent. The equations that take in to account the simultaneous deposition processes of the dispersed particles on the sorbent and their separation, which can be caused by low efficiency of coolant cleaning.The main problems and disadvantages of accumulation of residual contamination of the sorbent layer during its backwashing are described. The reasons of decrease of sorption capacity at accumulation of residual pollution of a layer are considered. The effect of residual sediment remaining after pre-washing on the filtration characteristics is analyzed. The intensity of sorption capacity loss is considered depending on the number of performed sorption-desorption cycles. The equation of dependence of the sorption capacity of the layer on the number of cycles of sorption-desorption was obtained. It is confirmed that the criterion of exhaustion of the sorption capacity of the filtering layer should not be an increase in pressure drop on it, but a decrease in the efficiency of purification of radionuclides of corrosive origin.