Screen Bowl Centrifuge Dewatering Process: A Parameteric Study

Screen bowl centrifugation process is widely used for fine coal dewatering due to its relatively low cost, high capacity of providing low-moisture content product as well as relative ease of operation and maintenance. However, screen bowl centrifuge tends to lose a significant amount of ultrafine clean coal to the main effluent and screen-drain streams. This study aims at obtaining a better understanding of the parameter main effects and interaction effects with an ultimate goal of improving the dewatering performance of a screen bowl centrifuge. A three-level factorial experimental design has been utilized to conduct a test program using a continuously operated screen bowl centrifuge having a bowl diameter of 0.5 meter. The results of this study indicate that moisture content of the clean coal product is affected by both feed solid content and the pool depth maintained in the centrifuge. On the other hand, clean coal recovery to the product launder was found to be a function of feed solid content and volumetric feed flow rate but independent of the pool depth. The interaction effect of feed flow rate and feed solid content also appeared to have a significant effect on the clean coal recovery.

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Influence of Hot Bed Spray Dryer Parameters on Physical Properties of Peppermint (Mentha piperita L.) Tea Powder

International Journal of Food Engineering ◽

10.1515/ijfe-2014-0182 ◽

2015 ◽

Vol 11 (1) ◽

pp. 115-125 ◽

Cited By ~ 1

Author(s):

Mohsen Fakher Dizaji ◽

Ali HamidiSepehr ◽

Gholamreza Chegini ◽

Javad Khazaei ◽

Ali Mansuri

Keyword(s):

Moisture Content ◽

Flow Rate ◽

Processing Parameters ◽

Mentha Piperita ◽

Spray Dryer ◽

Feed Flow Rate ◽

Heated Air ◽

Bed Temperature ◽

Rotary Speed ◽

The Cost

Abstract In this study, the effects of some processing parameters on moisture content, drying yield, bulk density, solubility and particle size of peppermint tea powders obtained from a hot bed spray dryer were investigated. In this method of drying, a heated bed is used instead of heated air to simplify spouted bed drying method and lower the cost of drying. A wheel rotary atomizer was employed for spraying of material and a frustum-shaped bed heated by thermal elements was applied around the atomizer. Independent variables were bed temperature (130, 140 and 150°C), feed flow rate (10, 20 and 30 L/h) and rotary speed of atomizer (7,000, 12,000 and 16,000 rpm). The moisture content of dried tea powders ranged from 3.13 to 4.87%. The highest drying yield (87.23%) and solubility (89.6%) were obtained at the bed temperature of 130°C and feed flow rate of 10 L/h.

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Effects Of Variables On The Production Of Red-Fleshed Pitaya Powder Using Response Surface Methodology

Jurnal Teknologi ◽

10.11113/jt.v56.51 ◽

2011 ◽

pp. 15-29

Author(s):

Mohd Azizi Che Yunus ◽

Ching Yaw Lee ◽

Zuhaili Idham

Keyword(s):

Response Surface Methodology ◽

Moisture Content ◽

Bulk Density ◽

Response Surface ◽

Spray Drying ◽

Air Temperature ◽

Flow Rate ◽

Feed Flow Rate ◽

Drying Conditions ◽

Central Composite

Teknik reka bentuk komposit pusat dalam kaedah gerak balas permukaan (RSM), telah dipilih untuk memeriksa pengaruh parameter-parameter pengeringan sembur terhadap kandungan lembapan dan ketumpatan pukal serbuk buah naga. Pemboleh ubah-pemboleh ubah tak bersandar dengan julat seperti yang disebutkan telah diuji kaji: suhu masukan (156-224°C), kadar aliran suapan (16.6-33.4 ml/min) dan kepekatan maltodextrin (31.6-48.4%). Keputusan menunjukkan bahawa data eksperimen dapat diwakili oleh bentuk polinomial tertib kedua. Bagaimanapun, hanya istilah linear mempunyai pengaruh mutlak terhadap keadaan serbuk. Parameter-parameter terbaik untuk mencapai nilai kandungan lembapan terendah adalah suhu masukan 224°C, kadar aliran suapan 22.9 ml/min dan kepekatan maltodextrin 40%, dengan jangkaan 3.88% kandungan lembapan. Nilai ketumpatan pukal yang maksimum iaitu 0.45 g/ml dicapai pada suhu masukan 156°C, kadar aliran suapan 16.6 ml/min dan kepekatan maltodextrin 48.4%. Kata kunci: Kaedah gerak balas permukaan; sembur kering; buah naga Central Composite Design technique from Response Surface Methodology (RSM) was used to investigate the effects of spray drying conditions on red-fleshed pitaya powder moisture content and bulk density. The spray drying independent variables and ranges are inlet air temperature (156-224°C), feed flow rate (16.6-33.4 ml/min) and maltodextrin concentration (31.6-48.4 %). Results showed that the data were adequately fitted to second order polynomial model. However, only linear terms proved to be significant for powder attributes. The best spray drying conditions within the experimental ranges for minimum powder moisture content of 3.88% would be inlet air temperature, feed flow rate and maltodextrin concentration of 224°C, 22.9 ml/min and 40% respectively. The maximum powder bulk density of 0.45 g/ml was obtained at inlet air temperature of 156°C, 16.6 ml/min feed flow rate and 48.4% maltodextrin concentration. Key words: Response surface methodology; spray-drying; red-fleshed pitaya

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CuS2 sheets: a hidden anode material with a high capacity for sodium-ion batteries

Journal of Materials Chemistry C ◽

10.1039/d0tc04946h ◽

2021 ◽

Author(s):

Shaohua Lu ◽

Weidong Hu ◽

Xiaojun Hu

Keyword(s):

Lithium Ion Batteries ◽

Anode Material ◽

Low Cost ◽

High Capacity ◽

Lithium Ion ◽

Sodium Ion ◽

Sodium Ion Batteries

Due to their low cost and improved safety compared to lithium-ion batteries, sodium-ion batteries have attracted worldwide attention in recent decades.

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Experimental and Modelling of Aqueous Radioactive Waste Treatment by Ultrafiltration

Revista de Chimie ◽

10.37358/rc.18.5.6278 ◽

2018 ◽

Vol 69 (5) ◽

pp. 1149-1151

Author(s):

Laura Ruxandra Zicman ◽

Elena Neacsu ◽

Felicia Nicoleta Dragolici ◽

Catalin Ciobanu ◽

Gheorghe Dogaru ◽

...

Keyword(s):

Flow Rate ◽

Suspended Solids ◽

Waste Treatment ◽

Operating Pressure ◽

Feed Flow Rate ◽

Permeate Flux ◽

Independent Variables ◽

Opposite Trend ◽

Process Factors ◽

Volumetric Flux

Ultrafiltration of untreated and pretreated aqueous radioactive wastes was conducted using a spiral-wound polysulphonamide membrane. The influence of process factors on its performances was experimental studied and predicted. Permeate volumetric flux and permeate total suspended solids (TSS) were measured at different values of feed flow rate (7 and 10 m3/h), operating pressure (0.1-0.4 MPa), and feed TSS (15 and 60 mg/L). Permeate flux (42-200 L/(m2�h)) increased with feed flow rate and operating pressure as well as it decreased with an increase in feed TSS, whereas permeate TSS (0.1-33.2 mg/L) exhibited an opposite trend. A 23 factorial plan was used to establish correlations between dependent and independent variables of ultrafiltration process.

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Effects of Fe-Doped Electrolyte and Feed Flow Rate Evaluation in Home Made Solid Oxide Fuel Cell

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1143/1/012007 ◽

2021 ◽

Vol 1143 (1) ◽

pp. 012007

Author(s):

Hary Devianto ◽

Isdiriyani Nurdin ◽

Pramujo Widiatmoko ◽

Kafi Adi Prasetya ◽

Basil Pradipta

Keyword(s):

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Flow Rate ◽

Solid Oxide ◽

Oxide Fuel ◽

Feed Flow Rate ◽

Rate Evaluation

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Column Study for Adsorption of Methylene Blue Dye using Azadirachta indica Adsorbent

Asian Journal of Water Environment and Pollution ◽

10.3233/ajw200050 ◽

2020 ◽

Vol 17 (4) ◽

pp. 47-52

Author(s):

Vibha Goswami ◽

Renu Upadhyaya ◽

Sumanta Kumar Meher

Keyword(s):

Methylene Blue ◽

Flow Rate ◽

Azadirachta Indica ◽

Packed Bed ◽

Blue Dye ◽

Feed Flow Rate ◽

Methylene Blue Dye ◽

Packed Bed Column ◽

Bed Height ◽

Percentage Removal

In this study, synthesised Azadirachta indica adsorbent was used for the removal of methylene blue dye using a packed bed column. The effect of feed flow rate, feed methylene blue dye concentration, and bed height of column on percentage removal of dye was studied. It was observed that the column bed exhausted rapidly at a higher flow rate and therefore, a breakthrough occurred faster. However, it was observed that bed exhaustion time increases on increasing the bed height from 2 to 10 inch at 10 mg/L feed dye concentration and feed flow rate of 40 ml/min. It was also found that the breakthrough curve is more dispersed and the percentage removal of dye increases on decreasing the feed methylene dye concentration from 150 to 10 mg/L. The percentage removal was found to be 96.89% at 20 ml/min of feed flow rate under 10 inch of bed height and 10 mg/L of feed dye concentration. The atomic absorption spectrophotometer and scanning electron microscope were used for estimating the effluent dye concentration from the column and morphological study, respectively.

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Improvement of long-term cycling performance of high-nickel cathode materials by ZnO coating

Nanotechnology Reviews ◽

10.1515/ntrev-2021-0020 ◽

2021 ◽

Vol 10 (1) ◽

pp. 210-220

Author(s):

Fangfang Wang ◽

Ruoyu Hong ◽

Xuesong Lu ◽

Huiyong Liu ◽

Yuan Zhu ◽

...

Keyword(s):

Electrochemical Performance ◽

Lithium Ion Batteries ◽

Solid Phase ◽

Low Cost ◽

Specific Capacity ◽

High Capacity ◽

Lithium Ion ◽

Side Reaction ◽

Chemical Route ◽

High Nickel

Abstract The high-nickel cathode material of LiNi0.8Co0.15Al0.05O2 (LNCA) has a prospective application for lithium-ion batteries due to the high capacity and low cost. However, the side reaction between the electrolyte and the electrode seriously affects the cycling stability of lithium-ion batteries. In this work, Ni2+ preoxidation and the optimization of calcination temperature were carried out to reduce the cation mixing of LNCA, and solid-phase Al-doping improved the uniformity of element distribution and the orderliness of the layered structure. In addition, the surface of LNCA was homogeneously modified with ZnO coating by a facile wet-chemical route. Compared to the pristine LNCA, the optimized ZnO-coated LNCA showed excellent electrochemical performance with the first discharge-specific capacity of 187.5 mA h g−1, and the capacity retention of 91.3% at 0.2C after 100 cycles. The experiment demonstrated that the improved electrochemical performance of ZnO-coated LNCA is assigned to the surface coating of ZnO which protects LNCA from being corroded by the electrolyte during cycling.

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