bbk 000000

UDC 628.16.087

FESENKO L. N., Skryabin A. Yu., Bessarabov S. Iu., Pchel'nikov I. V., Ignatenko S. I.

Utilization of concentrate from reverse osmosis units  in the production of electrolytic sodium hypochlorite


Owing to high efficiency and minimum chemical consumption reverse osmosis and nanofiltration have been widely used in process flow schemes of drinking water demineralization and softening and water preparation for industrial use (in steam boiler-houses, recycling cooling circuits, heat network make up etc.). However, the methods of membrane separation are accompanied by concentrate generation which is very difficult to process and utilize. The data on utilization of concentrates of membrane separation units with obtaining chloride-sodium raw material for the production of electrolytic low-concentrated sodium hypochlorite is presented. Since the waste stream of reverse osmosis units contains elevated concentrations not only of chloride ions but also of Са2+, Mg2+, НCO3- and SO42- ions it would be reasonable at the first stage to reduce the amount of process concentrate by repeated concentrating as per flowchart «nanofiltration-reverse osmosis». Further on the concentrate of nanofiltration containing mainly Са2+, Mg2+ and SO42- divalent ions is subject to chemical treatment as per flowchart: at the first stage with barium compounds; at the second stage with sodium carbonate and hydroxide. This will allow separating practically insoluble BaSO4 from the solution with its precipitation in a vortex reactor or first-stage lamellar separator; then CaCO3 and Mg(OH)2 low-soluble in alkaline environment are precipitated in the second stage reactor. BaSO4, CaCO3 and Mg(OH)2  insoluble salts removed from the mass balance are dewatered in a filter-press and sold as commodity or raw products. Aqueous solution of sodium chloride is repeatedly concentrated by three-stage reverse osmosis to obtain 2–2.5% aqueous solution of table salt – high-grade raw material for the production of electrolytic sodium hypochlorite with 6–8 g/l chlorine equivalent concentration. Chlorine-containing product can be used for drinking and waste water disinfection, biocidal processing of cooling to­wers, heat exchanging units for preventing and removing biofouling, washing ultra-and microfiltration membranes, disinfecting water treatment facilities and equipment, pipelines and other components used in the production of drinking and process water.

Key words

, , , , ,

The further text is accessible on a paid subscription.
For authorisation enter the login/password.
Or subscribe


  1. Fesenko L. N., Pchel’nikov I. V. [Evaluation of the economic efficiency of sodium hypochlorite production by sea water electrolysis]. Book of reports of XII International Scientific and Technical Conference Dedicated to the Memory of S. V. Iakovlev, Academician of RAS. Moscow, MGSU Publ., 2012, pp. 59–67. (In Russian).
  2. Kudriavtsev S. V. Sovershenstvovanie tekhnologicheskikh parametrov ustanovok polucheniya elektroliticheskogo gipokhlorita natriya dlya obezzarazhivaniya vody [Improving the process parameters of the units for electrolytic sodium hypochlorite production for water disinfection. Ph. D. thesis in Engineering Science. Novocherkassk, 2009, 161 p.].
  3. Vider B. L., Gorshenin A. P., Itkin G. E. [Advanced method of electrolytic sodium hypochlorite production and its application]. Vodosnabzhenie i Sanitarnaia Tekhnika, 2005, no. 1, pp. 26–27. (In Russian).
  4. Fesenko L. N., Denisov V. V., Skriabin A. Iu. Dezinfektant vody – gipokhlorit natriya: proizvodstvo, primenenie, ekonomika i ekologiya [Sodium hypochlorite – water disinfectant: production, use, economics and ecology. Under the editorship of Denisov V. V. Rostov-on-Don, Publishing House of the North-Caucasus Scientific Centre of the Higher School of the South Federal University, 2012, 246 p.].
  5. Medrish G. L., Teisheva A. A., Basin D. L. Obezzarazhivanie prirodnykh i stochnykh vod s ispol’zovaniem elektroliza [Disinfection of natural and waste water with the use of electrolysis. Moscow, Stroiizdat Publ., 1982, 81 p.].
  6. Pervov A. G., Andrianov A. P., Gorbunova T. P., Iurchevskii E. B. [The technology of reverse osmosis concentrate disposal in water treatment systems]. Vodosnabzhenie i Sanitarnaia Tekhnika, 2012, no. 8, pp. 20–26. (In Russian).
  7. Pervov A. G., Andrianov A. P., Gorbunova T. P. [Development of membrane techniques with reduced water consumption for own needs]. Vodosnabzhenie i Sanitarnaia Tekhnika, 2010, no. 6, pp. 13–21. (In Russian).
  8. Skriabin A. Iu., Fesenko L. N., Pchel’nikov I. V., Ignatenko S. I. [Addressing the problems of ecological compa­tibility and zero-discharge technologies of electrolytic sodium hypochlorite production for drinking water disinfection]. Vodo­ochistka, 2014, no. 3, pp. 9–16. (In Russian).

vstmag engfree 200x100 2

mvkniipr ru