Anti-Caking Agents for Low Density Ammonium Nitrate (LDAN)

Ammonium nitrate (AN) is widely used as a low-cost blasting agent. It has a high tendency to absorb moisture leading to degradation through several processes, including surface recrystallization, which results in crystal bridging and can generate severe caking if the product is not protected from moisture ingress.

Not only is the moisture itself detrimental to explosive ammonium nitrate’s use as a blasting agent (loss of sensitivity), generation of caked product results in a loss of porosity and air voidage. This, in turn, results in poor oil absorption and eventual reduction in the performance of the ammonium nitrate for its intended function, i.e., as a blasting agent. Moreover, severely caked ammonium nitrate in warehouses may lead to an increase in sensitivity.

Arkema’s Galoryl^® ATH range of anti-caking agents is applied to explosive ammonium nitrate, also known as low-density ammonium nitrate (LDAN) or industrial grade ammonium nitrate (IGAN) at the end of the ammonium nitrate production process, usually in a rotating coating drum. Our custom-made formulations are designed with high anti-caking and hydrophobic properties. They are designed to adhere to the porous prilled ammonium nitrate’s surface and provide a hydrophobic barrier against moisture. Galoryl^® anti-caking agents are also very effective at impeding the formation of crystal bridges and preventing recrystallization at the substrate surface.

Unlike other more traditional anti-caking agents, Galoryl^® products are neutral, resulting in no ammonia release upon application. Our coatings are available in a range of melt points and can be adapted for specific processes.