SU1503582A1 - Method of purifying solutions from radioactive iodine - Google Patents

Abstract

The invention relates to methods for decontamination of drinking water by sorption methods involving the use of sorbents modified with additives that increase the selectivity of sorption, and can be used at municipal water supply stations for cleaning iodine from radioactive iodine. The method can also be used in waste decontamination schemes NPP. The aim of the invention is to increase the degree of purification from all inorganic forms of radioactive iodine and increase the time of the protective effect of the sorbent layer without its regeneration. The goal is achieved by the fact that the solution contaminated with radioactive iodine is passed through a layer of highly basic anion exchanger in mixed I-C1-form with an I content of 15-25% of the full exchange capacity of the sorbent at 1 height of its layer 1.5-2 m and speed passing a solution of 2.9-4 m / h;, 1 tab. WITH

Description

The invention relates to methods for decontamination of drinking water by sorbent methods involving the use of sorbents modified with additives. The public is highly sensitive to segregation of sorption, and can be used at urban iodine, an industrial station for purification of radioactive iodine of drinking water. The method can also be applied to a scheme for deactivating nuclear radioactive waste.

The aim of the invention is to increase the degree of clearing from. all inorganic forms of radioactive iodine and an increase in the protective times of the sorbent layer without its regeneration.

The essence of the method lies in the fact that the solution, contaminated with radioactive iodine, is passed through a layer of highly abundant anion exchange resin in a mixed I -Cl-form with a content of 1-15-25% of the total exchange capacity of the sorbent.

When radioactive iodine gets into natural fresh water, along with J and J, oxygen-containing pnyosh is formed. , 10, 10 ,,

sh

YU.

The formation of these forms is associated with the occurrence of hydrolysis and oxidative-reducing processes. These forms of iodine are characterized in neutral media (decontaminated water) by the slow kinetics of isotope exchange with G and 1.

To implement the radiochromatographic regime, which allows the process to be carried out without regeneration of the sorbent, when cleaning the mixtures containing other oxygen-containing anions, it is necessary that the sorbent change the chemical state of the oxygen-containing iodine anions, i.e. possessed dostagochny restorative action. This is achieved by impregnating the sorbent with iodide ions reducing JOn to free iodine. The resulting free iodine is either sorbed on the 1 or C1 forms of the anion exchanger with a high rate (1)} by the distribution target, LI enters the process of isotope exchange.

The significance of the intervals given in the formula is due to the following ib, i: ir .-; mon. Ugsley: s:; 11th content of NII 1 in a sorbent of 25% of the full exchange capacity of the sorbent increases the cost of the sorbent without increasing efficiency, with a content of 1

- less than 1 5% dramatically increases overshoot

I. In case of pyso gss slogan

At the same time, 1.5 m and the transmission rates of the races more than 4 m / h, the decontamination factors are reduced. Reducing the flow rate to values below 2.9 m / h leads to an unjustified drop in process performance.,

Below are examples of the implementation of the proposed method.

Example 1. Anion exchanger AB-17 is produced by the industry in 01 form, treated with a solution of potassium iodate at the rate of 8.8 per I kg of air-dry sorbent. The duration of treatment is up to I day. The treated anion exchange resin contains I in the amount of 15% of the total exchange capacity of the sorbent. Water contaminated with radioactive iodine in the form of a mixture of forms 1, 1 ,, HI, 10, and 10 is passed through a prepared sorbent of a feusote of 2 m) at a flow rate of A m / h. Coefficient of water purification from radioactive iodine 83.

Examples 2-9 are performed as example 1, the results are shown in the table.

The iodine content is less than 155J from the total exchange capacity of the sorbent (examples 5,6) or more than 75 (example 7), as well as a decrease in the layer’s kystoy below 1.5 m (npiiMep 8) and an excess flow rate (example 9) do not provide effect) cleaning of solutions from radioactive iodine.

Thus, the proposed method provides effective cleaning of the solution from all inorganic fluorescent filters, TooT 1Vnogo-iodine

Ф о р м

3 o b e g e i u

The method of cleaning solutions from radioactive iodine, includes passing a contaminated solution through a layer of a highly basic anion exchanger, so as to increase the degree of purification from all inorganic forms of radioactive iodine and increase the protective time of the sorbent layer without regenerating it, Anisnite is used in a mixed I-CV-form with a G content of 15–25% o1 of full exchange capacity at a sorbent layer height of 1.5–2 m and a transmission rate of the solution of 2.9–4 m / h.

Claims (1)

F about r m at. G; but inventions A method of purifying solutions of radioactive iodine, including passing a contaminated solution through a layer of highly basic anion exchange resin, characterized in that, in order to increase the degree of purification of all inorganic forms of radioactive iodine and increase the time of the protective effect of the sorbent layer without its regeneration, anion exchange resin is used in mixed I * - C1 ~ form with a G content of 15-25% of the total exchange capacity at a sorbent layer height of 1.5-2 m and a solution transmission rate of 2.9-4 m / h. At- Content I to KI consumption Speed g ------- Length Time Coef Production Prime measures anionite for re- FLOW, LAYER con Finn- vodi- chakne ----------- -----—. poda ashyu- m / h m So- ent 'gel- 7. from half- mEq nita a the one deac nost Noah g given form FROM type- 1 n ‘ valuable mu, g / kg tions filter capacities m ³ 7h ----. J L -——---_ 3 one 0,035 5.8 four 2 1800 8.3 four No cleaning 6 fifty 1/5 290.5 four 2 1800 31,2 four Also 7 95 3.32 552 four 2 1800 8.3 four one fifteen 0.525 87 four 2 1800 83 four Efficient cleaning