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1

The role of microbubble dose in combined microflotation of fine particles

Rulyov Nickolaj

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 4

art. no. 190630

EN

Flotation of small particles is one of the global challenges facing the mineral raw materials processing industry. Large amounts of non-ferrous and rare metals are lost in the flotation tailings in the form of mineral particles below 15 μm in size as a result of the low effectiveness of their capture by coarse bubbles generated in conventional flotation machines. The method of combined microflotation, developed in recent years, uses conventional coarse bubbles (CB) and microbubbles (MB) produced in the stand-alone generator of air-in-water microdispersion, which serves as the flotation carriers. Depending on the MB dose, the effect of their application may be positive or negative. The theoretical analysis of various mechanisms of particle transfer onto the surface of coarse bubbles and further into the froth layer allowed to obtain the formula for the optimal MB dose 𝑓 = 𝑑!⁄2𝑑"𝜌", where 𝑑! is MB size; 𝑑" and 𝜌" respectively are the size and the density of particles. Experiments performed on the copper ore flotation tailings at the Atalaya Mining (Spain) and Chaarat Kapan (Armenia) concentrators showed that, besides the optimal MB dose in the range of 1-3 ml/g, there is another optimal MB dose in the range of 10-20 ml/g, where the copper recovery increases by several percent compared to the reference test (𝑓 = 0). The deep minimum in copper recovery is observed in the area between the optimal MB doses, which is by several percent lower than the value in the reference test.

2

Experimental study of quartz classification in the enhanced gravity field using Falcon concentrator

Zhang Ling, Yang Lu, Hou Haochun, Zhao Yan, Lin Jun, Zhang Zeliang, Bu Caiyun, Zheng Xinran, Fu Dong

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 6

art. no. 175242

EN

The classification and separation of minerals happen in the traditional gravity separation simultaneously. This paper focuses on the classification performance of quartz particles in the enhanced gravity field. The classification efficiency of single quartz particles decreased then increased with the increase of rotational angular velocity, while it decreased with the increase of backwash water pressure. The classification efficiency of -0.5 +0.25mm, -0.25 +0.125mm, -0.125 +0.074mm, -0.074 +0.045mm and -0.045mm quartz was higher than the corresponding narrow size of -0.5mm quartz in general. The “fish-hook” phenomenon appeared in the partition curve of -0.5mm quartz under small/large rotational angular velocity and small backwash water pressure, and the dip point could be found in fine particles region, which indicated that the “fish-hook” was closely related with operating parameters and particle size. A medium rotational angular velocity and larger backwash water pressure could be helpful to avoid the appearance of “fish-hook” in fine particles region and achieve a better classification performance. This investigation is beneficial to understand the regularity of particle migration in the enhanced gravity field.

3

Introducing key advantages of intensified flotation cells over conventionally used mechanical and column cells

Hassanzadeh Ahmad, Safari Mehdi, Khoshdast Hamid, Güner Mustafa K., Hoang Duong H., Sambrook Tim, Kowalczuk Przemyslaw B.

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 155101

EN

The present paper introduces the key advantages of ImhoflotTM, JamesonTM, and RefluxTM flotation cells over the conventionally used mechanical and column cells from different perspectives. The impact of slurry mean retention time, bubble size distribution, and energy input was studied for all cell types. The mean retention time of laboratory scale ImhoflotTM (V030-cell) and RefluxTM flotation cells (RFC100) were measured experimentally using KCl as a tracer. Also, initially a statistical and practical overview of previously installed ImhoflotTM, and JamesonTM cells was presented in this work. It was found that more industrial data is available for the JamesonTM cell. The diagnostic results showed that RefluxTM, JamesonTM, and ImhoflotTM functionally operate similarly based on providing intensive turbulence in the downcomer. They were initially applied to the Australian and the UK coal industries and installed in the cleaning stage of flotation circuits, while there are now more applications in a wide variety of minerals across the world in different flotation stages. First pilot trials on a Russian gold ore were reported operating both JamesonTM and ImhoflotTM cells at the rougher-scalper and cleaner stages providing superior results using the ImhoflotTM cell as rougher-scalper and the JamesonTM at the cleaner. Formation of sub-micron and micron-sized bubbles, effective hydrodynamic characteristics, and low capital and operating costs were reported as major advantages of intensified flotation cells over the conventionally used ones in improving the recoverability of ultra-fine particles. Literature data showed that these cells provide greater gas-hold-up values (40-60%) over the mechanical (5-20%) and column cells (5-25%) with substantially lower power inputs. It was indicated that low mean slurry retention time could lead to a potential enhancement in their throughputs, but further industrial measurements are required to prove this statement. The RefluxTM cell showed a plug-flow mixing regime, while ImhoflotTM V-Cell followed the trend of perfect mixing and plug-flow dispersion regimes.

4

Application of magnetic separation and reverse anionic flotation to concentrate fine particles of iron ore with high sulfur content

Dehghani Fahimeh, Khosravi Rasoul, Pazoki Amir, Kebe Moustapha, Jahanian Reza, Siavoshi Hossein, Ghosh Tathagata

Physicochemical Problems of Mineral Processing

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2022

|

Vol. 58, iss. 3

art. no. 145420

EN

The sulfur content in iron ore causes technical problems in the process of sintering iron ore in steel and alloys, and environmental problems in discharging the tailing. The major challenge in the iron ore processing plant is handling the finer particles. The key objectives of this research included the concentration of Band Narges Mine iron ore (< 150 μm) as well as the reduction of the sulfur content to achieve a marketable product. First, the mineralogical characterization of iron ore was established, which showed that Fe3O4, SiO2, and CaO were the predominant minerals in the ore body. Moreover, magnetite particles with a size of < 150 μm were mainly locked into the associated gangue mineral. Second, metallurgical experiments were conducted, including magnetic separation and froth flotation. To increase the iron grade and recovery and decrease the sulfur content, two separate process flowsheets were tested, three steps of magnetic separation with a magnetic field strength of 2000 G were used in the first process flowsheets, followed by regrinding to < 74 μm and application of a three-stage reverse flotation. The overall iron grade and recovery were 76.38% and 67.9%, respectively, from this flowsheet. A five-stage successive reverse flotation followed by three stages of magnetic separation at 1000 G was carried out in the second flowsheet. The final recovery and grade of iron for this flowsheet were 77.15% and 64.3%, respectively. The ultimate content of sulfur was estimated at 0.74%.

5

Influence of particle size on flotation separation of ilmenite, olivine, and pyroxene

Yang Yaohui, Xu Longhua, Liu Shujun, Deng Jian

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 5

106--117

EN

The rock type in Panxi area is changing from gabbro type to olivine pyroxene type, which makes it difficult for enterprises to obtain better beneficiation indexes at present. In order to solve this problem, we use a variety of modern test techniques, such as zeta potential measurements, Fourier-transform infrared (FTIR) spectroscopy, adsorption amount measurements, and mineral-reagent interaction energy simulation to analyze the influence of particle size on mineral flotation behavior and the interaction of fine-grained minerals in this paper. The experiments results indicate that the presence of fine-grained (-19 um) mineral particles is deleterious to the flotation of ilmenite, the ilmenite recovery decreases as the microfine grade content of pyroxene and olivine increases, distribution of narrow size minerals is beneficial to the minerals flotation performance, and the order of sodium oleate (NaOL) adsorption strength on different ilmenite crystal planes is (1011) > (0001). The research results of this paper deepen the understanding of the olivine type ilmenite resources in Panxi area, enrich the theoretical system of flotation separation of refractory ilmenite, and provide theoretical support for the key technical problems of flotation separation of ilmenite in Panxi area.

6

Improving separation efficiency of galena flotation using the Aerated Jet Flotation Cell

Li Si, Wang Yuhua, Lu Dongfang, Zheng Xiayu, Li Xudong

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 3

513--527

EN

The low separation efficiency of traditional mechanical flotation cells for galena flotation primarily was caused by the low collision probability between bubbles and fine particles and high detachment probability of coarse particles. A flotation device named Aerated Jet Flotation Cell (AJFC) was adopted to improve the separation efficiency of galena flotation. Reducing bubble size and optimizing turbulence distribution were respectively confirmed as effective ways to improve fine galena-bubble collision efficiency and decrease detachment probability of coarse galena. In AJFC, micro-bubbles in diameter of 0.1-0.3 mm were generated by forcing compressed air to pass through porous high-density polyethylene tube, and high shear rate and appropriate turbulence were provided by installing a sparger with holes at the end of downcomer. The key parameters, including sparger hole number, turbulent kinetic energy (TKE), air-slurry ratio and superficial gas velocity (Jg) were optimized to achieve a desired separation performance of galena flotation. Separation efficiency of 62.54 % at a residence time of 2.25 min was achieved by AJFC, while separation efficiency of 59.12 % at a residence time of 7.5 min was achieved by mechanical flotation cell. Besides, AJFC had less loss of Pb in tailings than mechanical flotation cell in the whole particle size range, especially for fine (-25 µm) and coarse (+74 µm) size fractions.

7

Jak szybko opada drobne ziarno?

Nad A.

Surowce i Maszyny Budowlane

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2018

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nr 5

58--61

PL

Poniższy artykuł jest analizą zjawiska sedymentacji grawitacyjnej zawiesiny ilasto-pylastej. Dokładnie omówiona została kwestia wpływu zawartości części stałych na prędkość opadania.

8

Biały proszek dla kruszywa

Nad A., Podsiadło K., Doan M. H.

Surowce i Maszyny Budowlane

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2018

|

nr 6

54--57

PL

Poniższy artykuł przedstawia analizę zjawiska sedymentacji grawitacyjnej zawiesiny gliniasto-pylastej pod wpływem działania środka chemicznego w postaci flokulanta. Dokładnie omówiona została w nim kwestia wpływu ilości flokulanta na prędkość opadania drobnych ziaren przy stałej zawartości części stałych na poziomie 5%.

9

Nanobubbles effect on the mechanical flotation of phosphate ore fine particles

Pourkarimi Z., Rezai B., Noaparast M.

Physicochemical Problems of Mineral Processing

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2018

|

Vol. 54, iss. 2

278--292

EN

Froth flotation is one of the main methods for processing of phosphate ores. However, flotation of fine particles, especially phosphate ores, has always been one of the fundamental problems. For example, about 10% of Esfordi phosphate processing plant ore with a grade of more than 16% P2O5 and d80 of less than 30 μm is sent to the tailing dam. Flotation using nanobubbles generated by hydrodynamic cavitation is one of the latest industrial techniques to recycle fine particles of minerals. A significant recovery increment in flotation of fine particles using nanobubbles has been one of the main topics of flotation science in recent years. Fine bubbles have important effects on the gas holdup, which is necessary in the froth flotation cell of mineral based process industries. At a given gas holdup, using finer bubbles can reduce frother consumption. An exclusive nanobubble generation system has been developed at Iran Mineral Processing Research Center (IMPRC) for evaluating the effect of nanobubbles on froth flotation. This device enhances venturi tubes and works based on cavitation phenomena. In this study, a comparison of conventional flotation and nanobubble enhanced flotation in mechanical cells was carried out on two types of phosphate ore samples. As a result, the flotation recovery had a significant increment of more than 30% in the case of using nanobubbles versus conventional flotation in the same grade of P2O5.

10

Experimental investigations of preparation of calcite particles by ultrasonic treatment

Toraman O. Y.

Physicochemical Problems of Mineral Processing

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2017

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Vol. 53, iss. 2

859--868

EN

This paper investigates breakage of calcite powder (d50 = 25.23 μm) to fine particle sizes using an ultrasonic generator (400 W, 24 kHz). The present study focuses on comminution of calcite powder in water media by ultrasonic treatment and the effect of some operational parameters such as treatment time (5–30 min), ultrasonic power (30-100% as amplitude), solid ratio (5-30% w/w), probe positions (0.5-2 cm) and cycle on the product size. Experimental results were evaluated on the basis of average particle size (d50). Sonication of calcite produced a drastic particle-size reduction (d50=12.89 μm) under optimal conditions.

11

Characteristics of cationic red x-grl adsorption by raw diatomite and diatomite concentrate

Ren Z., Guan J., Gao H., Tian J., Wen Y., Zheng R.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 1

44--55

EN

Raw diatomite (RD) and diatomite concentrate (DC) were used for the adsorption of cationic Red X-GRL from aqueous solutions. Mono-factor experiments were carried out to investigate the effects of the operation factor, and adsorption kinetics, isotherms, thermodynamics and mechanisms were explored. Similar trend for X-GRL adsorption onto RD and DC was observed. The adsorption capacity of dyes increased slightly with temperature, and the neutral pH was the optimum level. The adsorption processes occurred in accordance with the pseudo second-order model and were well fitted by the Langmuir isotherm model. The main driving forces of the physical adsorption on the diatomite were electrostatic attraction and van der Waals force. The RD could uptake more X-GRL than DC due to its higher content of fine particle and therefore, due to higher surface area available for adsorption. Raw diatomite as a cheap absorbent for X-GRL removal can be suggested as a promising supplement to activated carbon.

12

The investigation of effect of wet-dry grinding condition and ball types on kinetic model parameters for kaolin

Umucu Y., Haner S., Tunay T.

Inżynieria Mineralna

|

2015

|

R. 16, nr 1

205--211

EN

Ceramics are products made from inorganic materials that are first shaped and subsequently hardened by heat. Many ceramic raw materials require crushing or disintegrating followed by dry or wet grinding to various degrees. Most of the energy is consumed in the grinding operations for the ceramic industry. As it is known, some of the energy during grinding is converted to heat that is fully not utilized in the grinding process. Thus, grinding is not a very efficient operation and it needs to be paid attention in detail. However, it is possible to set up a grinding system with a low energy consumption and higher efficiency of fineness before they can be used in ceramic manufacture. The type of grinding media exerts significant influence on milling performance in terms of product size and energy consumption. In recent years, various shapes of grinding media including rods, pebbles, and cylinders have been used as an alternative to balls. Cylinders have received particular attention because they have a greater surface area and higher bulk density than balls of similar mass and size. The objective of this study is to compare the wet and dry grinding of most frequently used ceramic raw materials namely, kaolin with the grinding of alumina ball type and cylbebs (pebbles).

PL

Produkty ceramiczne wykonane są z materiałów nieorganicznych, które najpierw się kształtuje, a następnie utwardza przy użyciu ciepła. Wiele surowych materiałów ceramicznych wymaga miażdżenia lub dezintegracji przy pomocy suchego lub mokrego mielenia w różnych stopniach. W przemyśle ceramicznym najwięcej energii zużywa się do reakcji mielenia. Jak wiadomo, część energii w trakcie mielenia zmienia się w ciepło, które nie jest w pełni wykorzystywane w procesie mielenia. Co oznacza, że mielenie nie jest zbyt opłacalną operacją i wymaga szczegółowej uwagi. Niemniej jednak, można ustawić system mielący z niższym wykorzystaniem energii i większą wydajnością rozdrabniania, zanim zostanie użyty w wytwórstwie ceramicznym. Rodzaj medium mielącego wywiera znaczący wpływ na proces mielenia w odniesieniu do rozmiaru produktu i konsumpcji energii. W ostatnich latach, jako alternatywę do kul wykorzystywano różnego kształtu medium mielącego, wliczając w to pręty, kamyki i cylindry. Największą uwagę zwrócono na cylindry, ponieważ posiadają większą powierzchnię właściwą i wyższą wielkość objętościową niż kule o podobnej masie i rozmiarze. Zamiarem badań jest porównanie mokrego i suchego mielenia najczęściej stosowanych materiałów ceramicznych, czyli kaolinu z mieleniem aluminiowymi kulami oraz przy użyciu cylbebu (kamyczków).

13

Masowy rozkład pierwiastków w próbkach pyłu zawieszonego pobranych w obszarze tła miejskiego: wyniki ośmiomiesięcznych badań w Zabrzu

Rogula-Kozłowska W., Klejnowski K., Rogula-Kopiec P., Błaszczak B., Mathews B., Szopa S.

Rocznik Ochrona Środowiska

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2013

|

Tom 15, cz. 2

1022--1040

EN

The analysis of elemental composition of ambient dust can help not only evaluate the environmental and health effects due to the air pollution but also identify emission sources. However, the whole number of projects and studies on concentrations and elemental composition of ambient (especially fine) dust hardly concern these issues in Eastern Europe. Neither is the chemical (and elemental) composition of the submicron ambient dust in Poland well recognized. There is also a shortage of data from long-term and parallel studies of the elemental composition of separate dust fractions. In the heavily polluted areas, the elemental composition of atmospheric aerosol and the dependence of elemental composition of particles on their size can appear essential for analyzing the toxicity of dust and its environmental effects. This study presents the results of determination and comparison of the elemental composition of four fractions of ambient dust in Zabrze (Poland), an urban area typical of the exposure of the Upper-Silesian Agglomeration population to the polluted air. The samples of the four dust fractions (fine: ≤1 µm – PM1, 1–2.5 µm – PM1-2.5, coarse: 2.5–10 µm – PM2.5-10, and 10–40 µm – PM10-40,) were collected during eight months (January–August 2009) with the use of a DEKATI-PM10 cascade impactor. All the dust samples (204 samples) were analyzed using a PANalytical Epsilon 5 spectrometer (EDXRF – energy dispersive X-Ray fluorescence spectroscopy). The minimum, maximum and average concentrations, for winter (January–April, heating season) and summer (May–August, non-heating season), of 38 elements from each of the four examined dust fractions were calculated. The influence of anthropogenic sources on the ambient concentrations of elements from each dust fraction was determined by analyzing the enrichment factors (EF). The strength of linear relationships (Pearson’s linear correlation coefficients) between each pair of elements was determined separately for fine and coarse dust. The highest ambient concentrations were assumed by two nonmetals – sulfur and chlorine; their concentrations were significantly lower in summer than in winter. Both sulfur and chlorine were mainly bound onto the finest particles. Their share in the coarse dust, even in summer, was small. They came from anthropogenic sources. Ambient, typical crustal, Si, Al, Fe, Mg, K, Ca, Ti, Sr, Rb in Zabrze came from natural sources regardless of the fraction they were bound to. Small seasonal variations in ambient concentrations of these elements or some of the concentrations higher in summer than in winter confirmed the fact. A significant portion of the mass of the crustal elements, especially of Al, Si and Fe, was concentrated in the coarse fractions. However, the mass distribution among the dust fractions indicates some of them (K, Ca, Mg, Rb, Sr) as coming partly from anthropogenic sources. It particularly concerns their part bound to fine dust in winter. The mass contribution of crustal matter to ambient dust was about 6.8 in winter and 9.7% in summer; the contribution to PM1 was half of it. Almost all remaining 27 elements (except for Mn, Zn, Ge, Sb, La) had the ambient concentrations not greater than 100 ng m-3, usually higher in winter. The average mass shares of each of these 27 elements in PM1, PM1-2.5, PM2.5-10, and PM10-40, were different and depended on the season of a year. Co, Cu, Zn, Pb and As were cumulated mostly in fine dust, while V, Mn, Co, Cr, Ni, Ag, Cd and Ba in coarse dust. The former, in fine dust, were assumed to be rather of anthropogenic origin and closely associated with combustion. The later originated partly from combustion (especially in winter) but their greater part was secondary and came from road dust. The largest contributors to the mass of the elements in fine dust in Zabrze are domestic furnaces and car engines, i.e. combustion of fossil fuels, biomass, and waste. The possible effect of industrial sources was also identified. The elemental composition of coarse dust is due to re-suspension of soil and road dust, and to a lesser extent, to municipal emission.

14

Utilisation of pressure filtration using filter presses for the dewatering of the finest particles of mineral concentrates

Piechaczek B., Gruszka G., Pyc A., Iero E.

AGH Journal of Mining and Geoengineering

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2013

|

Vol. 37, no. 2

53--62

EN

This paper presents the utilisation of pressure filtration using horizontal filter presses for the dewatering of the finest particles of mineral concentrates. This paper also presents the results of a successful application of a filter press to dewater the finest grains (sediment) of coal at Jas-Mos coal mine in Jastrzębie Zdrój, Poland.

PL

Artykuł prezentuje zastosowanie filtracji ciśnieniowej z użyciem poziomych pras filtracyjnych do odwadniania najdrobniejszych ziaren mineralnych. Artykuł zawiera ponadto wyniki udanego wdrożenia prasy filtracyjnej do odwadniania najdrobniejszych ziaren (osadu) węgla dla materiału z kopalni Jas-Mos w Jastrzębiu Zdroju, Polska.

15

Analysis of efficiency of grinding in ball and rod mills dependably on contents of fine particles in feed

Foszcz D., Gawenda T.

AGH Journal of Mining and Geoengineering

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2012

|

Vol. 36, no. 4

17-30

EN

The paper presents the analysis of efficiency of the work of ball and rod mills dependably on granulation of the feed, particularly on fine particles contents. The analysis was conducted on the basis of the laboratory and industrial results realized as the part of research works for O/ZWR KGHM PM SA. The efficiency of grinding process was evaluated by the factor describing increase of certain chosen particle size fractions in mill yield. The issue of determining fine particle fractions before operations of comminution is crucial from the point of view of economics of conducting processing process. The liberation of fine particle fractions, so-called "ready" for further operations not requiring comminution on certain level influences on comminution costs and expected capacity of comminuting devices. It is very important to determine the efficiency of comminuting operations dependably on fine particles contents for correct determination of comminution system scheme. It allows determination of expected efficiency of classification process and optimization of investments costs connected with purchase of devices of certain capacity as well operative ones connected with energy consumed by designed technological system.

PL

W artykule przedstawiono analizę efektywności pracy młyna kulowego i prętowego w zależności od uziarnienia nadawy a w szczególności udziału klas drobnych. Analizę przeprowadzono na podstawie wyników badań laboratoryjnych oraz przemysłowych wykonanych w ramach prac badawczych dla O/ZWR KGHM PM SA. Efektywność procesu mielenia oceniano wskaźnikiem przyrostu określonych wybranych klas ziarnowych w wylewie młyna. Zagadnienie wydzielania drobnych klas ziarnowych przed operacjami rozdrabniania jest niezwykle istotne z punktu widzenia ekonomiki prowadzenia procesu przeróbki. Wydzielenie drobnych klas ziarnowych tzw. "gotowych" do dalszych operacji nie wymagających rozdrabniania na danym stadium wpływa na koszty rozdrabniania oraz oczekiwaną wydajność urządzeń rozdrabniających. Niezwykle istotne dla prawidłowego określenia schematu układów rozdrabniania jest wiec ustalenie efektywności operacji rozdrabniania w zależności od zawartości ziarn drobnych. Pozwala to określić oczekiwaną efektywność procesu klasyfikacji i umożliwia optymalizację kosztów inwestycyjnych związanych z zakupem urządzeń o określonej wydajności i operacyjnych związanych z energią elektryczną zużywaną przez zaprojektowany układ technologiczny.

16

Fine particle emissions from combustion of wood and lignite in small furnaces

Branc M., Horák J., Ochodek T.

Environment Protection Engineering

|

2011

|

Vol. 37, nr 2

123-132

EN

Assessment of household combustion emission was carried out based on data on meteorological conditions in heating season (outdoor temperature) and the emission factors. Available emission factors, both for various fuels and for various combustion devices differ markedly. The results of experimental determination of particle matter emissions, including dividing total suspended particulate matter into various fractions (PM10 and PM 2.5) have been presented in the paper. Various combustion devices to burn wood and lignite were used in experiments. Samples were taken in a dilution tunnel with the help of an impactor. It was found that specific emissions differ significantly during the combustion cycle. Compared to the used emission factors, differences are evident. It was found that TSP specific emissions depend mainly on the type of construction not its age.

17

Mixing system for highly concentrated fine-grained suspensions

Moravec J., Jirout T., Rieger F., Krátký L.

Polish Journal of Chemical Technology

|

2009

|

Vol. 11, nr 4

52-56

EN

The mixing equipment for highly concentrated fine-grained suspensions must be designed differently from the equipment in which a suspension with a low concentration of the solid phase or bigger particles is mixed. It is due to the different rheological properties of the suspensions. In this work we are trying to find a suitable mixing system for a highly concentrated fine-grained suspension. The aim was to determine an effect of particular geometrical parameters of the tested mixing systems on a suspension process, especially from the energetic viewpoint. The energetic costs of all the used mixing systems were compared on the basis of the power consumption which was necessary for reaching the state of sufficient suspension movement in the whole mixed bulk. As a result, it was confirmed that multistage impellers can be used even in standard vessels (with a liquid level height equal to a vessel diameter) with a profit. During experiments, the state of sufficient movement was determined by a visual observation of the suspension at the vessel bottom, at the wall and also at the suspension level.

18

Measurements of aerosol size distribution in urban areas of Upper Silesia

Skubacz K.

Archives of Environmental Protection

|

2009

|

Vol. 35, no. 4

23-34

EN

Deposition of aerosols in the respiratory tracts depends on their size distribution. Investigation of such distribution has therefore great meaning for appropriate assessment of risk caused by hazardous pollutants that appear in environment both as a result of human activities like industry, emission from motor vehicles, municipal emission due to house furnaces and natural phenomena. The results of screening measurements of size distribution performed in several places located on highly populated areas in Upper Silesia, Poland are described in this paper. The applied equipment makes it possible to cover the range from several nanometers up to 20 žm, practically all particles that belong to the respirable class. Obtained results prove that a lot of particles having a size of the order of submicrons are produced close to high density traffic roads. This concentration strongly changed in time.

PL

Depozycją aerozoli w układzie oddechowym zależy od rozkładu ziarnowego aerozoli. Badanie rozkładu ma zatem duże znaczenie dla właściwej oceny zagrożenia spowodowanego przez szkodliwe substancje pojawiające się w środowisku bądź to w następstwie ludzkiej aktywności takiej jak produkcja przemysłowa, komunikacja i paleniska domowe bądź też w wyniku naturalnych procesów. W pracy opisano i oceniono wyniki pilotażowych pomiarów rozkładów ziarnowych aerozoli wykonanych w kilku miejscach zlokalizowanych na terenach zurbanizowanych. Zastosowana aparatura pomiarowa umożliwiała wykonanie badań rozkładów ziarnowych w szerokim zakresie od kilku nanometrów do 20 žm obejmującym praktycznie całą frakcję cząstek respirabilnych. Uzyskane rezultaty wskazują, że w miejscach położonych blisko dróg o dużym natężeniu ruchu pojawiają się duże liczny nanometrowych aerozoli, których liczba ulega w czasie dużym wahaniom

19

Ocena rozkładów gęstości i współczynników dyfuzji w biofilmie immobilizowanym na materiale drobnoziarnistym

Tabiś B., Siudzińska R.

Przemysł Chemiczny

|

2005

|

T. 84, nr 4

250-253

PL

Omówiono sposób określania rozkładów dwóch podstawowych wielkości wpływających na szybkość procesu mikrobiologicznego w biofilmie immobilizowanym na materiale drobnoziarnistym, a mianowicie gęstości biofilmu i współczynników dyfuzji reagentów. Wielkości te w zasadniczym stopniu decydują o wartościach współczynnika efektywności biofilmu, czyli o ogólnej szybkości procesu. Wykorzystano w tym celu opublikowane dane doświadczalne otrzymane w dwufazowym i trójfazowym złożu fluidalnym.

EN

The av. reactant diffusivity and biofilm av. d. data detd. in a series of biofilms varying in thickness enable their distribution patterns to be established as functions of a current coordinate in the biofilm. The resulting equations take on the form related to the geometry of the film-growing substrate and to the functions adopted to describe the av. d. and diffusivity in relation to film thickness. Lin. regression suffices to det. the correlation parameters. The diffusivity and esp. the av. d. varied considerably in the biofilms grown on small spherical particles used in 3-phase fluidization bioreactors. The data reported on Pseudomonas putida microorganisms applied in a 2- and a 3-phase fluidization bioreactor were used to show how the biofilm efficiency and thus the overall process rate was affected.

20

Multivariate statistical modeling of urban aerosol monitoring data

Tsakovski S., Barbieri P., Bauer H., Puxbaum H., Simeonov V.

Chemia i Inżynieria Ekologiczna

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2004

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Vol. 11, nr 6

489--496

EN

The present communication represents the advantages of the multivariate statistical treatment of environmental data (aerosol data collection from an urban region). The fine aerosol particles (PM 2.5) from a site with heavy traffic and from a semi-rural sile ale treated by cluster and principal components analysis in order to identify pollution sources. Five latent factors determine the data structure in the first site and four in the second. They represent the influence of vehicles, road dust, mineral salt content or secondary aerosol emissions and explain over 80% of the total variance. The apportioning procedure reveals the impact of each source on the total mass or on the total concentration of the chemical species. The major part to the formation of the total mass or concentration is based on the contribution of traffic factors or secondary aerosol emissions.

PL

Zbiór danych monitoringowych dla aerozoli o drobnych cząstkach (PM 2.5) pochodzących z terenu miejskiego (o dużym nasileniu ruchu samochodowego oraz z obszaru półrolniczego) poddano statystycznej analizie wielu zmiennych. Dla identyfikacji źródeł zanieczyszczenia wykorzystano analizę klasterów (grup) oraz analizę głównych składowych (komponentów). Pięć ukrytych czynników charakteryzowało dane dotyczące struktury pierwszego obszaru, a cztery pozostałe drugiego obszaru. Przedstawiają one wpływ pojazdów, pyłu drogowego, zawartości soli mineralnych lub wtórnej emisji aerozoli i wyjaśniają około 80% całkowitej wariancji. Procedura rozdziału określa wpływ każdego źródła na całkowitą masę lub stężenie związków chemicznych. Główna część tych zanieczyszczeń (określoną ich masą lub stężeniem) jest spowodowana ruchem drogowym lub wtórną emisją aerozoli.