SU1213569A1 - Method of processing washing solutions - Google Patents

Description

The invention relates to the cleaning of detergent solutions and can be used mainly in the nuclear power industry, where liquid waste containing surfactants and inorganic detergents, as well as radioactive contaminants, are formed in special laundry.

The aim of the invention is to provide the possibility of re-using a washing solution containing radioactive contaminants due to the selective separation of these contaminants.

When water-soluble polymers with carboxyl and crown ether functional groups are added to waste detergent solutions, the complexation reaction with ions of radioactive isotopes takes place. The resulting large MOLC complex is delayed by a semipermeable ultrafiltration membrane, and the remaining components of the solution surfactant and detergent substances penetrate the semipermeable membrane. Potka that has passed through the membrane can be returned for reuse, most of the surfactant and all inorganic detergents are not lost, are used many times. The concentrate contains a complex of radioisotopes, micellar surfactants, mechanical suspension in the form of suspensions.

Example. The treated washing solution coming from the laundry room, contains as washing substances, g / l: surfactant 7, hexametaphosphate

Table

The results of the processing of spent laundry detergent solutions

Volume, l, 100

Concentration, g / l:

PAV7

g xamet phosphate5

sodium 5, soda 3, oxalic acid 1.5, suspended particles 0.1, and radioactive contamination in the form of Cs isotopes, and, each specific activity, CI / l: 1.5-10, 1.510 and 1-10, respectively .

Acid, mol.m., is added to the solution before processing. 10 in the amount of 1. MG / L and a polymer with a crown ether functional group of 24-crown-8 mol.m. 10 in the amount of 1 mg / l. Then the solution is passed through an ultrafiltration UMA-200 cellulose acetate cellulose membrane with an average size of under 20 nm under a pressure of 15 MPa. The results of the treatment solution are presented in table. one.

The purified solution contains radioactive isotopes in an amount less than the permissible concentration. About 100% of inorganic detergents and 85% of surfactants are returned for reuse.

Mol.m. the polymeric complexone is closely related to the parameters of the ultrafiltration process, its lower limit is 5 10 10 because the pores of the branes for the maximum possible retention of the complex must have a size of not more than 10 nm, membranes with smaller pores have low specific productivity. The upper mass limit of 1-10 is associated with an increase in the viscosity of the solution, the pumping of which requires more energy.

The lower limit of the polymer concentration of 1 mg / l provides a high degree of purification, which does not change significantly with increasing amounts of added polymers.

99.5

6 5

0.5

.00

The specific activity

Ci / l:

Cs

Cs

1L

With

60

Number of suspensions, g / l Oh, 1

Table 2

The dependence of the purification coefficient for Y-radioactivity on the concentration of polymers (membrane UAM-150)

Cobalt Coefficient

Polymer concentration with 24-crown-8, mg / l

Radioactive cleaning ratio

Editor O. Fedotov

Compiled by N.Kekishev

Tehred M. MarginTal Proofreader M. Sharoshi

Order 5268/2 Circulation 663 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, .Raushska nab. 4/5

Production and printing company, Uzhgorod, st. Project, 4

; Continuation of Table I

10 10

-eight

-eight

3.6 10

3,

ten

-eight

3.4-10 O

-ten

3-10

-b

3-10- 2 10 20

25 30 30

0.5 3

ten

35 40 40

Claims (1)

METHOD FOR PROCESSING WASHING SOLUTIONS containing surface active and inorganic substances by ultrafiltration by adding water-soluble organic compounds containing carboxyl groups to the solution to be processed, followed by passing 4e ^J washing solutions to cut a semipermeable membrane, characterized in that, in order to allow reuse of the washing a solution containing radioactive contaminants, due to the selective selection of these contaminants, add hydrogen to the solution soluble polymers mol, m 5 x 10 ³ - ⁶ 1yu containing crown ether functional groups in an amount of not less than 1 mg / l, and as organic compounds containing carboxyl groups are used polymeric organic acid molecular weight 5-U ³ - 1 * 10 ⁶ in an amount of not less than 1 mg / l. W SP 05 ζ ©