Patent · US Expired

Process for the reducing emissions during prilling of material such as ammonium nitrate

US5514307A · kind A · utility

9Cited by
15References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 25, 1994
Grant dateMay 7, 1996
Priority date
Expiry dateJul 25, 2014

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC05G5/12
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

This invention relates to an improvement in prilling whereby water is atomized into a prill tower to affect faster solidification of the prill, and in particular, the outside surface of the prill by providing an increased rate of surface cooling while reducing the required air flows in the tower. This results in a major reduction in air pollution potential in the form of both fume and particulate while at the same time allowing substantial production rate increases. Specifically, the invention relates to quick freezing the outside surface of the prill by flash evaporation of finely atomized water particles on the surface of the prill or in extremely close proximity to the prill to greatly lower the vapor pressure at the prill's surface and by continued flash evaporation to enhance cooling so as to allow upward flowing air to be reduced to a point where micro-prills which are formed in prilling can settle in the prill tower while obtaining the same or increased production rates. More specifically, the present invention relates to an improvement in melt prilling of water sensitive materials, in particular, ammonium nitrate, urea, potassium nitrate and other water soluble melts which …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.