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Bubbling properties of frothers and collectors mix system

Batjargal Khandjamts, Guven Onur, Ozdemir Orhan, Karakashev Stoyan I., Grozev Nikolay A., Boylu Feridun, Çelik Mehmet Sabri

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 152890

EN

This paper studies the effect of the type and concentration of selected frothers and collectors mix system on the bubble sizes (Sauter mean diameter, SMD) of bubbling flow produced in a micro flotation cell and the determination of bubble size distribution (BSD). The usage of dodecyl amine hydrochloride (DAH) collector on the critical coalescence concentration of commercial frothers PPG200, PPG400, and PPG600 was investigated in detail. The results of these studies showed that the usage of DAH decreased the CCC of these frothers. Each frother + collector mixing system exhibited its unique ability in preventing coalescence of the bubbles in the order of PPG200 < PPG400 < PPG600. The factorial experiments established that the type of the frother, collector, and their concentration had a major effect on the size of the bubbles. The BSD in the presence of PPG600 + DAH mix system resulted in a little bit wider BSD which indicated the effect of frother type in mixed systems.

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Critical coalescence concentration (CCC) of various surfactants used as flotation reagents in mineral

Szyszka Danuta

Mining Science

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2022

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Vol. 29

221--232

EN

The role of flotation frothing agents in the flotation process is generally known, especially due to the size of bubbles and the stability of the foam formed. In recent years, a number of new reagents have been introduced. The purpose of this article is to present a comprehensive database containing the characteristics of surfactant families discussed using the parameter of the so called the Critical Coalescence Concentration (CCC). This article presents an analysis of the experimental data set by the author and the experimental data published in the literature.

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Frother critical coalescence concentration and dose in flotation of copper-bearing carbonaceous shale

Szyszka Danuta

Mining Science

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2019

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Vol. 26

289--295

EN

The paper presents the yield of carbon-and-cooper-bearing shale from the Legnica and Glogow Copper Basin flotation also called Kupferschiefer in the presence of ethylene, diethylene and trithylene glycol butyl ethers (C4E1, C4E2, C4E3) frothers characterized by frother normalized concentration that is ratio of the frother concentration, and its critical coalescence concentration expressed in different units. It was found that the oucome of flotation is identical provided that the frother concentration is expressed in milimoles per Mg.

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Wpływ zastosowania chlorku chlorocholiny na zawartość wybranych mikroelementów w nasionach komosy ryżowej (Chenopodium quinoa Willd.)

Gęsiński K., Majcherczak E., Gozdecka G., Żary-Sikorska E., Wichrowska D.

Inżynieria i Aparatura Chemiczna

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2015

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Nr 5

235--236

PL

Analizowano wpływ zastosowanego terminu oprysku i dawek retardanta Antywylegacza Płynnego 675 SL chlorku chlorocholiny (CCC) na zmiany akumulacji wybranych mikroelementów (Fe, Cu, Mn, Zn) w nasionach komosy ryżowej. Zbadano dwa terminy wykonania oprysku na etapie fazy rozwojowej roślin Sili par liści. Dawkę retardanta oceniano na trzech poziomach: l, 2 i 3 dm3•ha-1, które porównano z badaniem kontrolnym - bez zastosowania preparatu. Stwierdzono istotny wpływ badanych czynników na zawartość wybranych mikroelementów w nasionach komosy ryżowej. Najwyższą zawartość Fe i Mn zaobserwowano na obiektach z dawką 3 dm3•ha-1 CCC i była ona wyższa w fazie 8 par liści. Jednocześnie zastosowanie CCC w uprawie komosy ryżowej stymulowało nieznaczne zmniejszenie zawartości Cu i Zn.

EN

An influence of spraying time and chloromequat chloride (CCC) retardant doses on changes in the accumulation of selected micronutrients (Fe, Cu, Mn, Zn) in quinoa seeds was analyzed. Two time deadlines for retardant spraying at the stage of 8 and 11 pairs of leaves plant development phase was checked. The retardant dose was evaluated in three levels at l, 2 and 3 dm3 ha-1, which was compared to the control test without the use of preparation. A significant influence of examined factors on the content of selected micronutrients in seeds of quinoa was confirmed. The highest content of Fe and Mn was observed on objects with a dose of 3 dm3-ha"' CCC and was higher in the 8 pairs of leaves stagc. At the same time the use of CCC in the cultivation of quinoa stimulated a slight reduction of Cu and Zn content.

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Improvements in the Structural Integrity of Resin Based Combustible Cartridge Cases (CCC) at Elevated Temperatures

Dey A., Athar J., Gogoi S., Navle P. B., Sikder A. K.

Central European Journal of Energetic Materials

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2015

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Vol. 12, no. 1

117--127

EN

An advanced, solvent-less resin based Combustible Cartridge Case (CCC), designed to resolve the inherent problems of shrinkage and limited mechanical strength associated with the gelatinisation of nitrocellulose, has already been developed. The felt-moulded components contain thermoplastic polyvinyl acetate (PVAc) resin as the binder and the enhanced mechanical strength is achieved by carrying out hot compaction of dry felts at an elevated temperature (105 ± 2 °C). Presently, resin based technology is adopted for tank gun ammunition and also for the developed modular CCCs, i.e. the Modular Combustible Case (MCC) for different types of artillery gun ammunition. However, during exhaustive trials conducted with the resin based CCCs in 120 mm tank gun ammunition at three temperatures, i.e. -10, 27 and 55 °C, severe geometrical deformation was noticed when the rounds were conditioned at 55 °C for 24 h., adversely affecting the loading of rounds into the gun chamber. This was attributed to the combined effects of softening of the resin at that temperature and the load of the projectile/ shell (14.4 kg) experienced by the CCC region during conditioning of the round in the horizontal mode. In order to resolve this problem of deformation, PVAc resin was required to be modified. The PVAc resin was modified to the form of a nanocomposite. PVAc nano composite was prepared by dispersing organically modified nano clay, i.e. Cloisite 30B, into the resin before making the CCCs. The nanocomposite of PVAc resin was characterized by FTIR, DMA, softening point measurement etc. The results showed a remarkable improvement in the glass transition temperature (Tg) and in the softening temperature of the modified PVAc resin. This modified PVAc resin was used to prepare CCCs. Furthermore, these CCCs were coated with hexamethylene diisocyanate (HMDI) on the inner and the outer surfaces. The isocyanate coating becomes crosslinked in the matrix, thereby improving the softening point as well as the mechanical properties of the CCCs. These modified CCCs were repeatedly tested at 55 and 60 °C for 24 h. After testing, it was found that no deformation had taken place and the assembled rounds were easily loaded into the gun chamber. The use of the PVAc nanocomposite in the preparation of resin based CCCs, followed by isocyanate coating, is an effective means of achieving the required improvement in structural integrity of the resin CCCs at elevated temperatures.

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Quant Ω Bridge MI 6010Q as an alternative to CCC in the development of the Czech Primary Quantum Standard of electrical resistance

Chrobok P., Svoboda P.

Elektronika : konstrukcje, technologie, zastosowania

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2008

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Vol. 49, nr 5

44-46

EN

In order to establish a Czech national quantum standard of electrical resistance, commercial Quantum Hall measuring system (Cryogenic QHR 2010) has been operated in CMI since 2003. In the years 2003-2007, the built-in reference standard resistor (TINSLEY 100 Ω) had been successfully linked twice a year to the Quantum Hall Device using the CCC and/or a room temperature resistance bridge (MI 6010C). Recently, a new method based on the Quant Ω Bridge MI 6010Q has been developed, that seems to be quite comparable to the CCC as to both the uncertainty and absolute precision. This room temperature bridge therefore offers a simpler and more user-friendly alternative to CCC as a part of the quantum primary resistance standard.

PL

W celu ustanowienia państwowego kwantowego wzorca oporu elektrycznego w Czeskim Instytucie Metrologicznym (CMI) od 2003 r. stosowano w CMI komercyjne stanowisko pomiarowe z kwantowym wzorcem Halla (Cryogenic QHR 2010). W latach 2003-2007 dokonywano dwa razy w roku porównania wzorcowego opornika odniesienia (TINSLEY 100 Ω) z kwantowym wzorcem Halla za pomocą kriogenicznego komparatora prądowego CCC i/lub mostka oporowego (MI 6010C) działającego w temperaturze pokojowej. Ostatnio opracowano nową metodę z kwantowym mostkiem oporowym Ouant Ω Bridge MI 6010Q, która daje podobne wyniki w dokładności i rozdzielczości pomiarów jak metoda z użyciem CCC. Mostek pracujący w temperaturze pokojowej może być częścią składową kwantowego, pierwotnego wzorca oporu elektrycznego, a jego użycie stanowi zatem alternatywę dla komparatora kriogenicznego CCC, prostszą w budowie i w obsłudze.

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Zastosowanie kriogenicznego komparatora prądowego do przekazywania jednostki miary rezystancji

Mosiądz M., Orzepowski M.

Pomiary Automatyka Kontrola

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2007

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R. 53, nr 9

19-22

PL

Przedstawiono zastosowanie kriogenicznego komparatora prądowego w procesie przekazywania jednostki miary rezystancji. Omówiono jego zasadę działania oraz możliwości pomiarowe w odniesieniu do innych metod transferu jednostki rezystancji.

EN

Article presents role of cryogenic current comparator in the process of resistance unit transfer. Its working principles and measurement possibilities in the comparison to other resistance unit transfer methods are described.