DENITRIFICATION OF MEDIUM LEVEL LIQUID RADIOACTIVE WASTES, WITH CATALYTIC BREAKDOWN OF NITROGEN OXIDES
The catalytic abatement by means of NH-3 of the NO-x produced in the radwaste conditioning has been studied. With reference to the gas produced in a bituminization plant, the thermodynamics and the chemistry of the NO-x catalytic reduction to nitrogen and H-2O have been evaluated. The following operational parameters have been experimentally studied: the catalyst bed temperature; the gas residence time; the vapour concentration; the NO-x concentration; the gas velocity; the catalyst grain size distribution; the catalyst time life. In order to obtain abatement yields of the order of 99,5 %, the following experimental conditions must be selected: gas residence time = 0,18 +- 0,02 sec. NH-3/NO-x = 1,0 +- 0,1 gas velocity = 1,5 - 2,0 m/sec / H-2O / gas <= 60 % V/V In the case of a bituminization plant, a NO-x catalytic reactor, if installed between the evaporator denitrator and the condenser, could reduce to less than 1/100 the volume of the NaNO-3 secondary wastes produced by the gas scrubbing.
Bibliographic Reference: EUR 9594 IT (1984) MF, 105 P., BFR 240, BLOW-UP COPY BFR 525, EUROFFICE, LUXEMBOURG, POB 1003
Availability: Can be ordered online
Record Number: 1989123061900 / Last updated on: 1987-01-01
Available languages: it