Index Geophysics

hrv SITNJENJE - PRVI STUPANJ U OPLEMENJIVANJU MINERALNIH SIROVINA

eng COMMINUTION - THE FIRST STEP IN MINERAL DRESSING

hrv Sitnjenje je proces u kojem pod djelovanjem mehaničkih sila mije¬njamo disperzno stanju čvrstih tvari. Disperzno stanje jednoznačno je određeno granulometrijskim sastavom. Do sitnjenja dalazi uslijed de¬formacije zrna, pri čemu deformacija ovisi o načinu nanošenja sile, njezinoj brzini i veličini. Drobljenje pojedinačnog zrna najučinkovitija je metoda sitnjenja, jer su gubici energije uslijed trenja i neproduktiv¬nog naprezanja u trenutku drobljenja izbjegnuti. Najveći gubici ener¬gije su u mlinovima s kuglama i to uslijed trenja između novostvorenih zrna i tih zrna s kuglama i oblogom mlina. Nove spoznaje dovele su do boljeg razumijevanja sitnjenja. u realnim uvjetima, te inovacijskih zahvata s kojima je povećana učinkovitost pojedinih uređaja i to kako u pogledu grano-sastava i raščina zrna tako i u pagledu utroška ener¬gije. Konstruirano je nekoliko novih drobilica od kojih se u praksi najčešće spominju visokotlačna drobilica s valjcima i inercijske konus¬ne drobi lice.

eng Comminution is the process in which by activity of mechanical forces the dispersion state of solid material is being changed. The dispersion state is definitely determined by the granulometric compo¬sition particle (size distribution). The comminution is a consequence of the particle deformation, in what this deformation is dependent on the force offering mode, its velocity and size. The breaking of individual particles is the most efficient comminution method because the energy losses owing to friction and unproductive tension in the instant of breakage are avoided. The greatest energy losses occur in ball mills and that because of the friction between the newly-formed particles and of these particles and the balls and the mill lining. New insights have led to a better understanding of comminution in real conditions and to innovative interventions which increased the efficacity of the individual devices, and that with regard to particle size distribution and particle dislocation degree as well as to energy consumption. Some new kinds of crushers have been invented, of whose most mentioned are the high pressure roll crusher and the inertial cone crusher.

Salopek, Branko

Bedeković, Goran

hrv sitnjenje;drobljenje zrna;energija;drobilice

eng comminution;particle breakage;energy;crushing machines

Faculty of Mining, Geology and Petroleum Engineering University of Zagreb

2000

text

info:eu-repo/semantics/article

info:eu-repo/semantics/publishedVersion

application/pdf

https://hrcak.srce.hr/13425

hrv https://hrcak.srce.hr/file/20586

Rudarsko-geološko-naftni zbornik

ISSN 1849-0409 (Online)

Volume 12

Issue 1

hrv

info:eu-repo/semantics/openAccess

The author and publisher rights are visible during the submission process, and ethical codex is available at http://hrcak.srce.hr/ojs/index.php/rgn/about/editorialPolicies#custom-0 .

The Bulletin is open access (OA, green model, CC-BY) journal what means that electronic versions of articles are accessible to readers, without any fees or registration.When use, please refer to Creative Commons license (BY type, http://creativecommons.org/licenses/by/4.0/ ).

Publisher copyright policies & self-archiving is also described at Sherpa organisation web (RoMEO service) based at the University of Nottingham (http://www.sherpa.ac.uk/romeo/pub/2374/).

All volumes of the Bulletin (from 1989) are available at Hrčak journal pages (http://hrcak.srce.hr/rgn-zbornik?lang=en).