Complex fertilizers are products containing two or three basic nutrients: nitrogen, phosphorus and potassium and may also contain secondary nutrients and micronutrients.

Manufacturing process of complex fertilizers consists on the chemical reaction of different raw materials that compose them, obtatining a slurry that is afterwards granulated, dried, classified and packaged. The nitrogen content in this type of fertilizers can be under nitric, ammoniacal or urea from, depending on the raw materials used in the manufacturing.

In the case of the NPK fertilizers manufacturing essentially two types of facilities are used: production plants via acidic mixture and production facilities via nitrophosphate.

Gas emission and treatment

The main areas of emissions come from the granulator and the drier and contain high quantity of dust mixed with NH₃ at high temperatures. In this case, the TECNIUM solution is to install a recovery system formed by a venturi followed by a multi-venturi, which provide high efficiency without clogging the equipments. The result is an efficient decontamination facility, a simple maintenance and the obtention as well, of a recyclable byproduct in form of ammonium salts (usually ammonium phosphate).