Milling separator

Mixing proceeds in the following way The ingredients, milled separately or in binary form, are weighed out into wooden boxes or barrels fitted with grips, and following the addition of ca. 8% of water (10% on hot and dry summer days) they are mixed by hand with a wooden paddle. The damp material is spread evenly over the tray of the runner. The layer of the material should not be less than 1 cm thick. 

High ranked bituminous coals like those of the Pittsburgh seam contain a distribution of discrete mineral matter particles in the size range from 50 to 1 pm which can be released and physically separated from the coal by normal fracture mechanisms experienced in wet ball milling. Separation of the product coal from the mineral matter dispersed in water was achieved by agglomeration methods. 

Sample Preparation. Cellulose powders, Whatman CFll, short fibrous cellulose powder with mean particle size 50-350 pm (Whatman International, Ltd.) and microcrystalline cellulose Avicel, mean particle size 27.6-102 pm, crystallinity index 0.60 (Avicel PHlOl, obtained from FMC, Ireland), were milled separately in a vibratory mill filled to 80% of volume with steel balls for 0 to 60 min. After milling, the samples were rubbed gently through a 50 pm sieve. All the treatments were performed at room temperature which is far below Tg temperature. The PAL temperature dependence data up to 200 do not show Tg onset Detailed information about sample preparation was described elsewhere(i0). 

Starch is obtained from crops by refining in several steps, depending on the crops source. For instance, corn starch is extracted from kernel by wet milling in order to split the kernel and remove the oil-containing germ. Finer milling separates the fibre from the endosperm, which is then centrifuged to separate the less dense protein from the densest starch. 

A trunnion at the discharge of the ball mill separates balls from slurry. The balls are then conveyed back to the feed. Balls gradually wear out through repeated feeding to the mill and must be replaced. 

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