{{short description|Small aggregate or globule of a material}} {{Wiktionary}} {{Other uses|Prill (surname)|Prill School}} A '''prill''' is a small aggregate or globule of a material, most often a dry sphere, formed from a melted liquid through spray crystallization.<ref name="Van'T Land 117">{{cite book |last1=Van'T Land |first1=C.M. |title=Industrial Crystallization of Melts |date=2004 |publisher=Taylor & Francis |page=117 |isbn=9780203021132 |url=https://books.google.com/books?id=Xo4zhU9DbJsC&dq=prilling&pg=PA117 |access-date=10 October 2022}}</ref>
'''Prilled''' is a term used in mining and manufacturing to refer to a product that has been pelletized. ANFO explosive typically comprises ammonium nitrate prills mixed with #2 fuel oil.<ref name="Jimino, Jimino, & Carcedo 113">{{cite book |last1=Jimino |first1=C. Lopez |last2=Jimino |first2=E. Lopez |last3=Carcedo |first3=Ayala |title=Drilling and Blasting of Rocks |date=1995 |publisher=Taylor & Francis |isbn=9789054101994 |page=113 |url=https://books.google.com/books?id=ebNArd17TH0C&dq=prilled+aluminium+ANFO&pg=PA113 |access-date=10 October 2022}}</ref> The pellets are a neater, simpler form for handling, with reduced dust.
The material to be prilled must be in a solid state at room temperature and a low-viscosity liquid when melted. Prills are formed by allowing drops of the melted prill substance to congeal or freeze in mid-air after being dripped from the top of a tall prilling tower. Certain agrochemicals such as urea are often supplied in prilled form. Fertilizers (ammonium nitrate, urea, NPK fertilizer) and some detergent powders are commonly manufactured as prills.<ref name=FertEncyl>Vasant Gowariker, V. N. Krishnamurthy, Sudha Gowariker, Manik Dhanorkar, Kalyani Paranjape (2009). ''The Fertilizer Encyclopedia''. John Wiley & Sons. {{ISBN|9780470410349}}. {{doi|10.1002/9780470431771}}.</ref> However prilling of ammonium nitrate and urea has in recent years been replaced by fluid bed granulation as this gives strong and more abrasion-resistant granules.<ref name="Van'T Land 117" />
Melted material may also be atomized and then allowed to form smaller prills that are useful in cosmetics, food, and animal feed.
==See also== * Shot (pellet)
==References== <references />
Category:Agricultural chemicals Category:Metallurgy
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