Determination of bubble size distribution in a laboratory mechanical flotation cell by a laser diffraction technique

• Autorzy: Mazahernasab R. , Ahmadi R.

Identyfikatory

DOI

10.5277/ppmp160214

• Języki publikacji: EN

Abstrakty

EN

In this study, a laser diffraction technique (LDT) was used to measure size distribution of bubbles generated in a two-phase system in a laboratory mechanical flotation cell. In LDT, a laser light beam passed through the bubbles inside the measurement cell and the scattered light was recorded by detectors. In order to show the effectiveness of LDT, an image analysis technique (IAT) was applied in parallel to measure the size of bubbles. To determine the bubble size by IAT, around 200 images were taken in each test. In addition, the important operating parameters of the mechanical flotation cell affecting the bubble size distribution, including the impeller speed, aeration rate and frother concentration, were investigated. The response parameter in this study was Db(50) which represent the size of bubble at which there is 50% of the distribution. The results of this study showed that the LDT and IAT techniques were in a good agreement when Db(50) was in the range of -800+400 μm and there was a discrepancy for Db(50) in the range of -400+100 μm. Furthermore, Db(50) decreased from 727 to 284 μm when impeller speed increased from 700 to 1200 rpm. Additionally, an increase in the aeration rate from 1 dm3/min to 2.5 dm3/min led to a rise in Db(50) from 418 to 456 μm. Finally, increasing the frother concentration from 10 to 60 ppm reduced the Db(50) from 704 to 387 μm.

Słowa kluczowe

EN

bubble size distribution; mechanical flotation cell; laser diffraction technique (LDT); image analysis technique; effective parameters

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Physicochemical Problems of Mineral Processing
• Rocznik: 2016
• Tom: Vol. 52, iss. 2
• Strony: 690--702
• Opis fizyczny: Bibliogr. 27 poz., rys., tab.

Twórcy

autor

Mazahernasab R.

• Faculty of Engineering and Technology, Imam Khomeini International University (IKIU), Qazvin, Iran

autor

Ahmadi R.

• Faculty of Engineering and Technology, Imam Khomeini International University (IKIU), Qazvin, Iran

Bibliografia

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