REC «Mekhanobr-Tekhnika» (St. Petersburg, Russia):
Korovnikov A. N., Director for sales of equipment for ore materials processing, Candidate of Engineering Sciences, korovnikov_an@ npk-mt.spb.ru
Trofimov V. A., Chief Trend Designer, trofimov_va@npk-mt.spb.ru

Main current trends in development of vibratory screens for dry disintegrated materials classification have been considered. The urgency of searching the ways for intensification of these processes is shown. Material process classification on a screen may be represented as a combination of three simultaneous processes: material transportation on screening surface from charge zone to discharge zone; particle size segregation on vibrating screen surface; passing of small size fractions through material layer and their screen sizing through sieve openings. In view of the complexity of studying the three simultaneous processes, the problem of improving main processing parameters still continues to be a pressing challenge, notwithstanding the extensive experience in development and operation of screens. One of the possible ways to increase throughput rate and efficiency of dry disintegrated materials classification by 0.1–5 mm size is application of inclined vibratory screen with modified screening surface. Modified sieve is designed with vertical longitudinally-oriented perforated baffle plates, dividing functional zones of material classification and express-discharge of material into undersize through screening openings in baffle plates. Operation of vibratory screen with modified sieves is compared with that of vibratory screen with flat perforated sieves. Screening efficiency on modified sieves is at an average of 1.8 % higher, than on perforated sieves. Specific throughput of modified sieves, if compared with perforated sieves, is at an average of 26 % higher. A possibility in principle to achieve dry disintegrated materials classification process intensification through application of modified screening surface on vibratory screens is shown.
The work was performed with the financial aid from the Ministry of Education and Science of the Russian Federation for the Project No. 14.579.21.0133 dated 03.10.2016. (UIPNI RFMEFI57916X0133).

1. Vaisberg L. A. Design and calculation of vibrating screens. Moscow: Nedra, 1986. 144 p.
2. Verbesserte Siebeffizienz. Enhanced screening efficiency. AT Mineral Processing. 2013. Iss. 07–08. p. 38.
3. Schutz S. «Green Screens». AT Mineral Processing. 2015. Iss. 07–08. pp. 58–62.
4. Höhere Leistungen und sicherer Betrieb. Higher capacities and safer operation. AT Mineral Processing. 2016. Iss. 07–08. pp. 44–45.
5. Mineral excitement. International Mining. 2016. October. pp. 26–38.
6. Bortnikov А. V., Vasilkov V. B., Samukov А. D., Romashev А. О. A vibrating sizing screen model (wedge wire screen) study. Obogashchenie Rud. 2011. No. 4. pp. 33–36.
7. Vaisberg L. A., Ivanov K. S., Melnikov A. Ye. Improvement of approaches to vibratory screening process mathematical modeling. Obogashchenie Rud. 2013. No. 2 (344). pp. 22–26.
8. Vaisberg L. А., Demidov I. V., Ivanov K. S. Mechanics of granular media under vibration action: the methods of description and mathematical modeling. Obogashchenie Rud. 2015. No. 4 (358). pp. 21–31. DOI: 10.17580/or.2015.04.05.
9. Pat. 155723 Russian Federation.
10. Pat. 139262 Russian Federation.
11. Pat. 2550607 Russian Federation.
12. Blekhman I. I., Blekhman L. I., Vaisberg L. А., Vasilkov V. B. Gradient vibratory segregation in loose materials size classification processes. Obogashchenie Rud. 2015. No. 5. pp. 20–24. DOI: 10.17580/or.2015.05.04.
13. Blekhman I. I., Blekhman L. I., Vasilkov V. B., Yakimova K. S., Vaisberg L. A. On vibrational diffusion segregation in granular media. Doklady Physics. 2016. Vol. 61, No. 1. pp. 8–10.
14. Mikhaylova N. V. Ecological effect of granitic rocks processing screenings’ dust fractions utilization. Obogashchenie Rud. 2016. No. 6. pp. 57–62. DOI: 10.17580/or.2016.06.10.
15. Arsentiev V. A., Vaisberg L. A., Samukov A. D. Nonwaste production of mass use building materials out of volcanic rocks. Gornyi Zhurnal. 2014. No. 12. pp. 55–63.