Browsing by Subject "grinding"

Now showing 1 - 5 of 5

Access status: Open Access ,
Analiza mechanizmu rozdrabniania ziaren w młynie strumieniowo-fluidyzacyjnym
(2007) Zbroński, Daniel
The basis of comminution mechanism of grains in the fluidized bed opposed jet mills aren't satisfactory explained. It results from the difficulties to determine the influence of all parameters process on the evolution of particle size distribution of milling product. The theoretical analysis and experimental results for grinding tests of limestone on the laboratory fluidized bed opposed jet mill are presented in the paper. The aim of research was to explain the influence of initial graining fed material on the comminution mechanism of grains in the grinding chamber of mill. The analysis showed that comminution in the mill takes place as a result of superficial attrition of grains, dynamic breakage of grains and cleavage of grain agglomerates.
Access status: Open Access ,
Analiza zależności prawdopodobieństwa rozpadu kryształu od jego rozmiaru w symulacji ultradrobnego rozdrabniania kryształów
(Wydawnictwa AGH, 2006) Łukasiak, Krzysztof; Przybyszewski, Krzysztof
We can use the algorithms base on the probabilistic methods for the simulations of the ultra fine wet grinding process of the solid state particles, which are built out of the crystals, agglomerates or aggregates, which is a stochastic process that we can call collective process, as it been proved in earlier publications (Przybyszewski et al. 2004, Łukasiak et al. 2005). In those papers, we pointed out how to use algorithms for the simulations of materials with non one-size distribution. In this paper we present the results of the simulations in which we considered relationship between a probability of the grain disintegration at its diagonal, cross section, volume and without any relationship.
Access status: Open Access ,
Energetyczne wskaźniki oceny procesu mielenia rudy miedzi i ich modelowanie
(Wydawnictwa AGH, 2005) Trybalski, Kazimierz; Krawczykowski, Damian
The paper concerns the energy consumption problem and copper ores grinding processes evaluation in grinding and classification system of one of KGHM »Polska Miedź« SA ore enrichment plants. The costs analysis of grinding and classification center was conducted, what identified its highest energy consumption. The energetic-technological factors evaluating grinding and classification processes were then proposed and calculated. On their basis the examples of models were constructed, which were regressive ones and neural networks forms, taking into consideration dependencies between process evaluation factors and energetic-technological data of investigated process. The comparison of given models was carried out.
Access status: Open Access ,
The evaluation of grinding process using MODSIM©
(2012) Umucu, Yakup; Deniz, Vedat; Bozkurt, Volkan
Istnieją programy do komputerowego projektowania systemów przeróbki surowców mineralnych zawierające również modele symulacyjne służące do projektowania młynów kulowych. Popularne są techniki symulacyjne ponieważ umożliwiają one rozwiązywanie skomplikowanych problemów bez dużej bazy danych. Jednym z takich symulatorów jest program MODSIM©, który oblicza szczegółowy bilans masowy dla jakiegokolwiek zakładu wzbogacania. MODSIM© może symulować zintegrowane systemy przeróbcze, zawierające w sobie podsystemy rozdrabniania. W artykule przedstawiono równania dla $S_i$ oraz $B_{ij}$ (funkcje rozkładu selekcji i rozdrabniania) określone dla składów ziarnowych otrzymanych po różnych czasach rozdrabniania i przy zastosowaniu parametrów modelu ($S_i$, $a_t$, $\alpha$, $\gamma$, $\beta$ i $\Phi_{J}$) dla różnych stosunków wypełnienia materiałem komory młyna. Dane eksperymentalne zostały statystycznie porównane z danymi otrzymanymi z programu MODSIM© przy zastosowaniu parametrów modelu.
Access status: Open Access ,
Wpływ prędkości obrotowej wirnika klasyfikatora przepływowego na osiągi młyna strumieniowo-fluidyzacyjnego
(2006) Zbroński, Daniel; Górecka-Zbrońska, Aleksandra
The necessity of applying materials with high degree of fineness in the contemporary technologies require used to modern technology in mechanical comminution of different substances, which will assure demanded particle size distribution of grinding product. The scientific performances are mostly aimed at the search for new work conditions of industrial grinding devices, which should guarantee parameters and fineness of grinding products and should decrease energy consuming of grinding and improve environmental protection. All the above seems to be met in the researches of granular materials grinding in the high-energetic fluidized bed. The fluidized jet grinding relies on keeping up a turbulent fluidization in the grinding chamber of mill, which is a result of collisions of air counter-fluxes. They make it possible to obtain high-energetic fluidized bed, which in turn ensures an effective comminution of tested granular material. The state of pulsatory fluidization is created in the certain surroundings of an axial zone of the fluidized bed. The state of fountain fluidization is created in the axial zone of the fluidized bed, which is characterised by carryover of grains in the zone of high velocities in the centre core of grinding chamber, then by gravitational falling of coarse fraction near walls and by carrying away of the small fraction by the flowing gas into the separation system. The theoretical basis and experimental results for the fluidized jet grinding of granular materials are presented in the paper. The researches were performed on a laboratory fluidized bed opposed jet mill. The experiment contained grinding tests of selected narrow size fraction of limestone in turbulent fluidized layer conditions. The aim of researches was to explain the influence of the values of rotational speed of flow classifier rotor on the efficiency of mill and the particle size distribution of grinding product. The determined masses and particle size distribution of grinding products make it possible to estimate the quality and the efficiency of the carried out fluidized jet grinding tests.