In 2013, EnviroCare was approached by a European engineering firm to provide ultra-low (< 5 mg/dNm3) emission technology for two new greenfield urea plants to be constructed in the USA. After months of vetting, which included extensive pilot testing on a similar process, EnviroCare’s solution was selected, fabricated and installed.

The urea manufacturing process normally utilizes either a granulator, which uses a fluidized bed approach or a prill tower, which is common over much of the world. The prill tower atomizes the urea melt at the top of the tower and the urea drops crystallize as they descend to the bottom of the tower. Fine urea dust and ammonia are the emission byproduct of the process.

EnviroCare’s design utilizes a staged approach, therefore the ability to scrub ammonia and urea separately (U+AS, U+AN) in the same unit or combined (UAS, UAN). The urea dust is scrubbed initially by quenching and the MMV stage; then the acid stage scrubs the ammonia. The high concentration urea liquor is recycled back the the evaporators and returned to the process. Our design also allows for the addition of a top-mount WESP, if required.