Prilled porous ammonium nitrate (explosive grade)
INCRO has technology for Ammonium nitrate (explosive grade) production. The process is divided into two clearly defined sections, Liquid and Solid. The liquid section, where ammonium nitrate solution is manufactured, is common for fertilizers and explosives, being the solid section the one setting the main differences between both grades.
LIQUID SECTION
INCRO has two processes to manufacture concentrated ammonium nitrate solution by reacting nitric acid 52-60% and ammonia. Depending on final use, solution can be manufactured with 80-96% concentration.
P-R PROCESS
It relies on the use of a small Pipe Reactor to react nitric acid and ammonia. It is a low to medium pressure (2.-4 barg) process and specially suitable for small plants, or batch production. Main advantages:
- Equipment small size.
- Added safety related to small solution holding volumes
- Easy start-up and shut-down
- Investment reduction
- Operating pressure allows using reaction steam for cost free concentration of obtained solution till 96%
MT-R PROCESS
Main reaction takes place at relatively low pressure (0.5-1.5 barg) in a solution loop, where ammonia, nitric acid and solution are thoroughly mixed in a multitubular reactor to ensure a smooth efficient reaction. Main advantages:
- A patented heat integration scheme allows getting 96% solution without imported steam, in spite of the low operating pressure
- The loop mixing scheme allows operating the plant in a wide capacity rage (20-120%)
- The low operating pressure / temperature greatly increases intrinsic process safety
- Extremely low ammonia / nitrate emissions thanks to the low temperature and mixing arrangement
- Low operating pressure allows using ammonia as free cooling agent
SOLID SECTION
POROUS LDAN
The 95-96% Ammonium nitrate solution is mixed with a prilling and porosity enhancing additive and the resulting mixture is sprayed, using INCRO’s specially designed buckets, from the top of the prilling tower.
Prills are collected at tower bottom and advanced to the pre-dryer / dryer, where humidity is reduced and porosity obtained.
Dry prills are screened, to separate oversizes and fines, which are melted and recycled to solution concentration, whereas on-size product is cooled down below 30ºC, using conditioned air. Finally product is coated before storage.
INCRO has designed a full integration / recycling / recovery of gases, including prilling tower gases, to recover nutrients, stabilize prilling tower conditions regardless of ambient conditions and reduce final washing step size.
INCRO’s process allows getting high quality porous ammonium nitrate, with very low moisture and high porosity (even 15%), suitable for high fuel absorption, producing ANFO explosive with excellent velocity of detonation, ignition capacity and propagation stability.
Both reaction systems are energy self-sufficient and incorporate high efficiency scrubbing systems, fully integrated with the reaction and concentration equipment.
Resulting solution has many uses:
- Raw material at 95-96% concentration to manufacture low density porous ammonium nitrate (explosive grade LDAN / PPAN) in a prilling tower
- To be directly dispatched for fertilizers production or explosive emulsions, at the concentrated required by Enduser (80-90% typically).
- To feed an attached granulation plant (90-97%), for NPKs or CAN production.
- To be concentrated till 99.5-99.8% for AN / CAN fertilizers grade prilling.
INCRO has carried out a continuous research to improve process safety, control and environmental efficiency, resulting in additional safety features / equipment, improved pH control systems and upgraded scrubbers that allow fully recovery of dirty condensates, as well as draining of clean condensates fully complying with the most strict legislation.
