Urea+Ammonium-Sulphate Fertilizers (UAS)
Sulphur (S) deficiency occurs widely in many parts of the world, due to a combination of factors: reduced use of Single Super Phosphate, which contains gypsum (CaSO4), more S being removed from fields due to increasing yields, and declining soil reserves due to erosion and leaching. In addition, emissions of sulphur dioxide from burning fossil fuels have historically provided a large S input to soil, as both rain and deposition of dust. As these emissions reduce, so soil deficiencies are increasing. Fertilizers enriched with S are now increasingly used to correct sulphur deficiencies. A better source of S may be ammonium sulfate (AS), which makes the S available in a form that can be directly taken up by plants.
A N plus S fertilizer can enhance the utilisation rate of N due to their well-known synergy; plants need sufficient levels of S to be able to utilise N efficiently. Together, N and S are vital building blocks for protein, so N and S should be applied at the same time.

Urea+Gypsum Fertilizers (UCS)
Phosphoric acid is a major feedstock for phosphate fertiliser, but, for every tonne of acid produced, an average of 5.4t of phosphogypsum (PG) is created. The outcome is that the annual PG output of International Fertiliser Association (IFA) members is in the range ~225-245 million tonnes. This amount and its contaminants pose a significant challenge for the industry to achieve better sustainability performance.
Urea is the most widely used nitrogen fertiliser with some 200 million tonnes sold annually but suffers from significant nitrogen losses through ammonia volatilisation, CO2 loss, as well as N2O emissions and nitrate leaching. The emissions of CO2 and N2O contribute significantly to the carbon footprint of urea fertilisers.
These two issues form possibly the two major environmental challenges in our industry.
Urea with gypsum represents a potential next-generation fertiliser. It can deliver improved agronomic performance and higher nitrogen use efficiencies. And, because of the large volume of urea use, it can potentially contribute significantly to the reuse of PG. By recycling industrial gypsum wastes and reducing nitrogen losses, the use of urea-gypsum fertilisers aligns with global goals for climate-smart, resource-efficient agriculture.

By adding Gypsum and/or AS to your Urea Prills you will gain a lot of benefits like:

• Significant higher plant production capacity
• Nitrogen and Sulfur (and Calcium) as Nutrients in one prill (Higher Nitrogen Use Efficiencies)
• Significant higher Crushing Strength
• Large particle size
• Negligible additional heat load on prilling tower
• Smaller Product Size Distribution with Kreber PrillTech
• No formaldehyde but coating will be required
• Ammonia and Dust emissions reduce
• Pay Back Times are a few months! (Read our UAS UCS Revamp Proposal below)

Together with our worldwide recognized team of Experts, UreaKnowHow.com can support you to produce Higher Value UAS and/or UCS in your plant:

• Feasibility Study (complete the Questionnaire below)
• Delivery of Mixing Units (test and commercial scale)
• Delivery of Finishing Section Test Plants
• Supply of and/or advise on Coatings
• Advice of dust and ammonia scrubbers (dry and wet)
• Advice on prill coolers
• Advice on storage in silos
• Commissioning and Start-Up Services