Treatment of waste soln. contg. ammonium nitrate - originating from prepn. of nuclear combustible material, by thermal decomposition of the ammonium nitrate

摘要

The treatment of waste solns. contg. ammonium nitrate and possibly urea, originating from the prodn. of combustible and/or fertile materials for nuclear reactors, involves injecting the relatively conc. soln. as a fine spray, into a zone of thermal decompsn. of ammonium nitrate. The decompsn prods. are sepd. by condensn. into a liq. phase and a gaseous phase. In this process, the waste soln. is first concd. in a thin film evaporator equipped with a vacuum pump. The concentrate then passes through a filtration apparatus and is fed into a cooled storage reservoir, from which it is introduced into a heated decompsn. tube. The decompsn. prods. pass through a condenser, and the condensate is collected in a reservoir. The process can be carried out continuously, and allows relatively conc. solns. to be treated without risk of explosion.