Wyniki wyszukiwania - Biblioteka Nauki

1

AN ASSESSMENT OF INFLUENCE OF SELECTED CHARACTERISTICS OF FEED ON THE RESULTS OF BALL MILL GRINDING PROCESS COURSE FOR POLISH COPPER ORES

100%

Gawenda T. , Saramak D. , Foszcz D. , Krawczykowski D. , Krawczykowska A. , Lewandowski D.

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2

Determination of the nip zone angle in high-pressure grinding rolls

100%

Saramak D. , Naziemiec Z.

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tom Vol. 49, iss. 1

243--253

EN

A proposal of the nip zone angle determination in high-pressure grinding rolls (HPGR) crush-ing process is presented in the paper. Knowledge of the nip zone angle value makes it possible to deter-mine the real maximum pressing force in the high-pressure comminution. Two methods of determination of this maximum pressure were proposed and verified. The first method is based on the roll’s geometry and the change of the HPGR chamber’s volume together with the roll rotation, while the second one considers the outlet gap width. Results of the nip zone angle calculations according to both methods are similar and show that the nip zone angle is around 3o. The verification was carried out in a piston-die press and experimental results show that the product size distributions from HPGR and piston-die press are similar. The methodology of the nip zone angle determination presented in the paper has then its practical confirmation. A proper determination of the nip zone border makes it possible to calculate the comminution probability of given type of material and is a basis for the HPGR crushing process modeling and optimization.

3

Efektywność energetyczna i środowiskowa rozdrabniania

100%

Macko M.

Inżynieria i Aparatura Chemiczna

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2009

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tom Nr 2

90-91

PL

Praca dotyczy zagadnień efektywności energetycznej procesu rozdrabniania, głównie wielokrawędziowego. W pracy podano wybrane wyniki badań zmiennych procesu rozdrabniania realizowanych na świecie, wskazano na możliwości ingerencji konstrukcyjnych, istotnie wpływających na poprawę efektywności energetycznej. W metodyce przedstawiono wyniki badań własnych oraz analizy wpływu cech konstrukcyjnych na końcową efektywność energetyczną.

4

Simulation of a high-pressure water jet structure as an innovative tool for pulverizing copper ore in KGHM Polska Miedź S.A.

100%

Borkowski P. , Shimizu S. , Peng G. , Oguma Y.

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tom Vol. 22

147--159

EN

Effective comminution of copper ore for further processing during flotation is still a challenge, both as a technological problem as well as for the high energy costs of such processing. A high-pressure water jet is one alternative method of preparing copper ore for final flotation, causing distinct enlargement of the surface of micronized particles, which could be profitable for copper production. As a consequence of such innovative processing, particles of copper ore become micronized, ensuring grain fractions directly useful for flotation at the exit of the pulverizing apparatus (the hydro-jetting mill).The paper presents some results of simulation as well as describing an analysis of the phenomena occurring inside the high-pressure water and abrasive-water jets of specific structures, elaborated in the aspect of developing hybrid jets of maximum erosive efficiency, potentially useful for effective pulverization.

5

Rozdrabnianie technologicznych elementów z tworzyw sztucznych

100%

Flizikowski J. , Bieliński M.

Zeszyty Naukowe Politechniki Białostockiej. Budowa i Eksploatacja Maszyn

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1998

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tom Z. 5

125-138

PL

Udzielenie odpowiedzi na pytania o warunki konstrukcyjno-technologiczne niezbędne do zaistnienia postulowanego stanu: minimum jednostkowego zużycia energii, racjonalnej wydajności i pożądanej jakości produktu rozdrabniania technologicznych recyklatów tworzyw sztucznych związanych z przemysłem spożywczym stanowiło podstawowy cel pracy. Wsad tworzyw sztucznych pochodzenia spożywczego i przeznaczonych do rozdrabniania jest bardzo różnorodny, począwszy od kompozytów z włóknami naturalnymi, poprzez kompozycje tworzywowo-papierowo-metalowe, aż do konstrukcji skorupowych. Nie ma możliwości zaproponowania uniwersalnej techniki rozdrabniania elementów z tworzyw o tak zróżnicowanych właściwościach - jako odpowiedzi na postawione pytanie.

EN

The primary aim of the study was to find an answer to questions concerning the necessary constructional and technological conditions which would ascertain minimum energy consumption, reasonable efficiency and desirable quality of recyced plastic elements used in food industry. As there is a great variety of food industry plastic destined for recycling it was found that there can be no universal technique of comminution of various property plastics.

6

Badanie wydajności młyna strumieniowo-fluidyzacyjnego

100%

Zbroński D. , Otwinowski H.

Inżynieria i Aparatura Chemiczna

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2006

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tom Nr 4s

158-160

EN

The theoretical basis and experimental results for fluidized fine jet grinding of granular substances are presented in the paper. The experiments consisted of grinding tests of selected narrow size fractions of limestone in turbulent fluidized layer conditions. The aim of research was to explain the influence of selected process parameters such as the initial graining and mass of the fed. working air overpressure and the rotational speed of classifier rotor on the efficiency of the fluidized bed opposed jet mill.

7

Effects of operating pressure and stand-off distance on coal comminution by waterjet

100%

Li Y. , Galecki G. , Şen G. A. , Şen S.

Physicochemical Problems of Mineral Processing

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2017

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tom Vol. 53, iss. 1

394--401

EN

Comminution of coal to ultrafine sizes by high-pressure waterjet coupled with cavitation cell provides a novel method for preparation of coal-water fuels for next generation, near-zero emission electric power generation. To establish the fundamental performance of the waterjet mill, the effects of the operating pressure and stand-off distance were comprehensively investigated using a high ash bituminous coal. The comminution products were evaluated in terms of the particle size, particle size distribution, and surface area change. The experimental results indicated that the waterjet-mediated comminution of coal was strongly affected by all these operating parameters. Higher operating pressure led to finer products, while the efficiency of the waterjet mill in terms of particle size strongly depended on the stand-off distance. This research provides a deeper insight into the high-pressure waterjet for coal comminution and a basis for process parameter optimization.

8

Influence of Copper Ore Comminution in HPGR on Downstream Minerallurgical Processes

100%

Saramak D. , Wasilewski S. , Saramak A.

Archives of Metallurgy and Materials

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2017

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tom Vol. 62, iss. 3

1689--1694

EN

Crushing processes taking place in high-pressure grinding rolls devices (HPGR) are currently one of the most efficient methods of hard ore size reduction in terms of the energy consumption. The HPGR products are characterized by a fine particle size and the micro-cracks formation in individual particles, which appears in downstream grinding processes, decreasing their energy consumption. The purpose of the paper was to analyze the effectiveness of a ball mill grinding process and flotation operations depending on the changeable conditions of run of the HPGR crushing process. The research programme carried out included crushing tests in the laboratory scale HPGR device at various settings of the operating pressure volume and selected qualitative properties of the feed material (i.e. particle size distribution). On the basis of obtained results the models, defining the grinding process effectiveness as a function of changeable conditions of HPGR process run, were determined. Based on these models the optimal grinding time in a ball mill was specified which is, in turn, the basis for optimization of operation the technological comminution circuits for a given material type. The obtained results proved that the application of HPGR devices in given copper ore comminution circuit may improve the effectiveness of downstream grinding process what leads to improvement of the entire circuit work efficiency through decreasing the process energy consumption and enhancing the product size reduction.

9

Badania użyteczności rozdrabniacza wielokrawędziowego i żyletkowego

88%

Macko M. , Tyszczuk K.

Inżynieria i Aparatura Chemiczna

|

2013

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tom Nr 2

47-48

PL

W pracy zaprezentowano koncepcję stanowiska badawczego rozdrabniania wielokrawędziowego i żyletkowego. Systemy rozdrabniania oparte o własne patenty realizują funkcję rozdrabniania z wysoką skutecznością. W układzie pomiarowym wykorzystano momentomierze i rejestratory prędkości obrotowej, dzięki czemu możliwe jest oszacowanie zapotrzebowania energetycznego na proces. Zaprezentowano wybrane wyniki badań próbek polimerowych.

EN

A concept of experimental setup for testing the multi-edge and razor-blade comminution is presented in the paper. Comminution systems based on our own patents perform the comminution with high effectiveness. Torque measure systems and the record of rotatory speed were used in the measuring arrangement. Thanks to that, it is possible to estimate the process energetic requirements. Selected results of comminution process of polymer samples are shown.

10

Economics of flotation plant against different size reduction alternatives and flotation grades

88%

Tuzcu E. T. , Demirtaş Z.

Physicochemical Problems of Mineral Processing

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2022

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tom Vol. 58, iss. 5

art. no. 154813

EN

This paper quantitatively shows the effect of run-of-mine (ROM) feed grade on flotation plant capacity, and also the combined effects of different feed grades and the size reduction alternative combinations on the project economics. Project economics are defined as CAPEX and OPEX The project profitability was estimated based on a “Cash Flow Model” along the life of the mine, which is ten years. The parameter for tracking project return or profitability is called NPV and IRR (internal rate of return), respectively. These parameters are standard parameters for control of project return in all engineering studies. In the scope of the study, there are a series of case studies including three different comminution alternatives in combination with three different ROM feed grade alternatives. Therefore, the nine case studies were compared based on economics which resulted from different equipment combinations and as well as the different types/amounts of process consumables. Among all the cases, Case 1 (Conventional circuit with 0.1% feed grade) gave the lowest CAPEX whereas Case 9 (High Pressure Grinding Rolls_HPGR circuit with 0.3% feed grade) gave the highest CAPEX. OPEX wise, Case 7 (HPGR circuit with 0.1% feed grade) produced the lowest whereas Case 6 (Semi-Autogenous Ball mill Crusher_SABC circuit with 0.3% feed grade) gave the highest value of OPEX. The NPV of the HPGR circuit with 0.3% feed grade case was found as maximum, which showed the quantitative effect of feed grade and equipment combination on flotation plant economics.

11

A quantitative study between HPGR and cone crusher aided ball mill grinding: mathematical modeling by evaluating the possible microfracture effect produced by HPGR technology and cone crusher

88%

Rodríguez-Torres I. , Tuzcu E. T. , Reyes I. A. , Rosales-Marín G.

Physicochemical Problems of Mineral Processing

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2024

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tom Vol. 60, iss. 1

art. no. 177620

EN

High Pressure Grinding Rolls (HPGR) have been used in the mining industry for decades. However, there are limited quantifications of the particle properties after comminution. Furthermore, the influence of microcracks in grinding provided by this technology has not been extensively quantified. In the recent work, there were two comminution paths tested: 1 (Jaw crusher + cone crusher + ball mill) and 2 (Jaw crusher + HPGR + ball mill). The possible weakening effect aiding ball mill grinding due to microcracks of HPGR path was shown via specific energy, fines generation and breakage rate measurements. To achieve a quantification about the impact of microcracks and the high rate of reduction rate of HPGR technology, first the product was reconstructed using Rosin Rammler's Weibull double formula and the similar particle size distribution was obtained by a conventional cone crusher. By this way the feed size distribution to the grinding stage remained constant regardless of the type of crushing process (HPGR or cone crusher). The results showed that the microfractures generated by the HPGR technology influence the specific energy consumption, fines generation and breakage rates. Ball mill after HPGR consumed 12.46 kWh/t of specific energy, however ball mill after cone crusher consumed 14.36 kWh/t of specific energy. The experimental methodology proposed in this paper maintains a consistent feed size range (-1500 to +41.31 μm) to show that the size reduction observed in the sample undergoing HPGR grinding is not the primary factor contributing to reduced energy consumption and increased fines generation. Instead, it is predominantly associated with the microfractures generated through the compression in HPGR technology; the energy reduction (optimization) of a grinding path is shown in the study.

12

Relationships between comminution and chemical, petrographic and mineralogical properties of ores, and their effect on concentration

88%

Deniz V.

Physicochemical Problems of Mineral Processing

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2022

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tom Vol. 58, iss. 5

art. no. 149892

EN

Especially in terms of energy costs, data on chemical, petrographical, and mineralogical analyses of ores or minerals can provide very important information for their production in the desired size distribution. Therefore, suitable crushing and grinding machines can be selected, taking into account the data affecting the comminution such as grain size, texture, metamorphism, and mineral or element contents. However, in most mineral processing plants, these data are rarely used to understand the response of ores or minerals to comminution. Analysis of the relationships between the chemistry, petrography, and mineralogy of ores and the breakage mechanism during crushing or grinding has been the subject of researchers in the comminution field in recent years. This study is a review of studies done so far on the relationships between the comminution and the chemical, petrographic, and mineralogical properties of different ores and minerals, and their effect on concentration.

13

De-agglomeration in high pressure grinding roll based crushing circuits

88%

Saramak D.

Physicochemical Problems of Mineral Processing

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2012

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tom Vol. 48, iss. 1

219-226

EN

The problems of possible application of de-agglometration operations into industrial HPGR-based crushing circuits, were presented in the paper. The HPGR technology has the potential to provide a significant circuit efficiency increases from technological (better comminution efficiency) and economic (lower energy- consumption of crushing process) scopes. However, the HPGR product is usually compressed into a flake product, what may constitute a technical challenge in effective classification of crushing product and the overall efficiency of the circuit. Three methods of flakes disintegration were investigated in the paper: an impact de-agglomeration, drum de-agglomeration and the wet one. Results showed that the wet and drum de-agglomeration operations are the most favourable methods of flakes disintegration. Additionally the wet process is especially beneficial for material with lower moisture content.

14

Influence of some mechanical properties of seed on energy requirement for their comminution

88%

Grochowicz J. , Nadulski R. , Bilanski W. K.

International Agrophysics

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1994

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tom 08

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nr 2

15

Energetyczna efektywność rozdrabiania w badaniach podstawowych i przemyśle

75%

Malewski J.

Kruszywa : produkcja - transport - zastosowanie

|

2020

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tom Nr 3

48--55

PL

Artykuł jest krótkim przeglądem rozwoju nauki o rozdrabianiu skał w kierunku zwiększenia efektywności procesów produkcyjnych na drodze doskonalenia narzędzi analitycznych do projektowania technologii, doboru odpowiedniej wielkości maszyn oraz kontroli procesów w instalacjach przemysłowych przeróbki kruszyw mineralnych.

EN

The article is a short review of the development of the science of comminution towards increasing the efficiency of production processes by improving analytical tools used for designing technologies, selecting the adequate size of machines and process control in industrial installations for mineral aggregate processing.

16

Optimizing the performance of high-pressure grinding roll based ore enrichment circuits

75%

Saramak D.

|

2012

|

tom T. 28, z. 4

87-99

EN

This article concerns the issues of modeling and the optimizational approach for the performance of ore comminution circuits. A typical, multi-stage comminution circuit was analyzed with the high-pressure grinding rolls unit operating at a fine crushing stage. The final product of the circuit under investigation was, at the same time, a flotation feed in which particle size distribution initially determined the effectiveness of flotation operations. In order to determine the HPGR-based comminution circuit performance, a suitable mathematical model was built wherein the target function was linked directly with the effectiveness of the flotation processes. The target function in the presented model considers the issue in terms of the flotation operation's effectiveness. The particle size distribution of individual comminution products and resulting from the weight recoveries of individual size fractions were criteria determining the quality of the comminution product. Weight recoveries of individual size fractions, in turn, were tied with the technical operating parameters of individual comminution devices. In the first model, profit maximization was the target function, while the second variant of the model took into account maximization of the useful mineral weight recovery in the concentrate. The HPGR application into ore processing circuits also results in energy saving benefits which were presented in a comparative analysis of the energy consumption of two comminution circuits - the first based on conventional crushing devices, and the second on the HPGR unit application which replaced the rod mills. The main benefit of such a modernization was almost two times lower energy consumption by the fine crushing stage and a decrease in the ball mills' grinding operations load through bypassing a part of the material directly for the rough flotation operations.

PL

Artykuł dotyczy zagadnień związanych z modelowaniem i optymalizacją pracy układów rozdrabniania rud. Przeanalizowano typowy kilkustopniowy technologiczny układ rozdrabniania rud, w którym wysokociśnieniowa prasa walcowa została zainstalowana na drugim stopniu rozdrabniania. Produkt końcowy analizowanego układu był jednocześnie nadawą do procesów flotacji, a skład ziarnowy nadawy determinował wstępnie efektywność procesów flotacyjnych. Aby określić efektywność pracy układu technologicznego przeróbki rud zbudowano odpowiedni model matematyczny pracy układu rozdrabniania, w którym funkcja celu została powiązana z efektywnością procesów flotacyjnych. Kryterium decydującym o jakości produktów rozdrabniania była wielkość ziarna i związane z tym wychody poszczególnych frakcji ziarnowych. Wychody poszczególnych frakcji produktów rozdrabniania zostały uzależnione od technicznych parametrów pracy urządzeń rozdrabniających. W pierwszym wariancie funkcja celu maksymalizowała efekt ekonomiczny, czyli zysk, natomiast drugi wariant zakładał maksymalizację odzysku składnika użytecznego w koncentracie. Aplikacje przemysłowe wysokociśnieniowych pras walcowych pozwalają na osiągnięcie wymiernych oszczędności energetycznych w modernizowanych układach rozdrabniania rud, co zostało przedstawione poprzez analizę porównawczą energochłonności dwóch układów rozdrabniania rud. W skład pierwszego układu rozdrabniania wchodziła kruszarka na etapie kruszenia wstępnego, młyn prętowy na etapie kruszenia drobnego oraz młyn kulowy na etapie mielenia. W drugim, zmodernizowanym układzie młyny prętowe zostały zastąpione wysokociśnieniowymi prasami walcowymi. Korzyści osiągnięte przy takiej modernizacji polegały na obniżeniu energochłonności etapu kruszenia drobnego prawie o połowę oraz zmniejszenie przerobu na etapie mielenia w młynach kulowych poprzez skierowanie części produktu prasy walcowej do procesu flotacji wstępnej.

17

Energetyczno-ekologiczna mapa rozdrabniania elementów recyklingu

75%

Macko M.

Inżynieria i Aparatura Chemiczna

|

2008

|

tom Nr 4

49-50

PL

Przedstawiono propozycję oceny procesu rozdrabniania wielokra-wędziowego nie tylko od strony wpływu cech konstrukcyjnych roz-drabniacza, ale z uwzględnieniem energetyczno-ekologicznych następstw projektowania, uwzględniającego docelowo strumienie surowców i materiałów, paliw i energii oraz urządzeń i obiektów.

EN

Some suggestions of precise evaluation of multi-edge comminu-tion arę presented in the paper. An essential difference between this and previous proposałs lies in the consideration of energeti-cally-ecological outcomes of the design. Raw materiałs, energy usage and appropriate devices arę considered.

18

Metoda doboru rozdrabniaczy do materiałów nie-kruchych

75%

Macko M.

Inżynieria i Aparatura Chemiczna

|

2010

|

tom Nr 5

75-76

PL

Dobór odpowiedniego rozdrabniacza dla materiałów nie-kruchych jest zagadnieniem ważnym. Od odpowiedniego doboru zależy nie tylko jakość produktu rozdrobnienia, ale również zapotrzebowanie energii na proces. W pracy wykorzystano aplikację SolidWorks do oszacowania wartości sił i naprężeń przy różnych wartościach kąta ostrza i wzajemnej prędkości elementów roboczych. Przeprowadzono analizę porównawczą otrzymanych wyników.

EN

A selection of proper grinder for non-brittle materials is an important iss Product quality and energy consumption depends on a suitable choice grinder. The SolidWorks application was used in the estimation of values forces and strength for different velocities and wedge angles. A comparat analysis of results was performed.

19

Analysis of the mechanics of the comminution process of minerals in crushers and high-pressure grinding rolls

75%

Brożek M. , Naziemiec Z. , Brożek M. , Naziemiec Z.

|

nr 3

20

Symulacja efektów rozdrabniania w prasie walcowej dla materiału o zmiennej zawartości ziaren drobnych

75%

Saramak D.

Gospodarka Surowcami Mineralnymi

|

2015

|

tom T. 31, z. 2

123--136

PL

W artykule przedstawione zostały wyniki badań dotyczących procesów rozdrabniania w prasie walcowej dla rud miedzi. Przeprowadzono próby kruszenia w laboratoryjnej prasie walcowej dla materiału o zmiennej zawartości najdrobniejszych klas ziarnowych, mianowicie: od 0 do 6 mm, od 0,3 do 6 mm, od 1,5 do 6 mm oraz od 2,5 do 6 mm. Próby przeprowadzono dla materiału o wilgotności naturalnej (tj. blisko 0%) oraz 2%. Uzyskane w tym zakresie wyniki pokazują, że dla materiału wilgotnego efektywność rozdrabniania nieznacznie się zmniejszyła, również pozbawianie nadawy kolejnych drobnych klas ziarnowych miało swój efekt w mniejszym stopniu rozdrobnienia produktów HPGR, jednak w miarę dalszego zwiększania wilgotności nadawy wskaźniki wydajności oraz energochłonności procesu uległy pogorszeniu. Analizując parametry pracy wysokociśnieniowej prasy walcowej można stwierdzić, że zwiększenie wilgotności nieznacznie zwiększa wydajność procesu, również w niewielkim stopniu redukując jego energochłonność. [...]

EN

The article presents the results of investigations over the comminution processes in HPGR for copper ore. Crushing tests were run in a laboratory HPGR device for the material with a variable content of fine particles in following size fractions: from 0 to 6 mm, from 0.3 to 6 mm, from 1.5 to 6 mm and from 2.5 to 6 mm. The tests were performed for the material with moisture content of 0 and 2%. The obtained results show that comminution effectiveness for material with an increased moisture content decreased slightly. Also the removal of individual finest particle size fractions from feed had its effect in a lower comminution efficiency, and increasing the feed moisture caused deterioration of the energy and capacity indices for the process. Analyzing the HPGR operating parameters it can be concluded that together with increasing the moisture content the process productivity slightly increases, together with some reduction of its energy consumption. [...]