Fertilizer prills and granules are hygroscopic products, MAP and NPK more than AN or Urea, but for all products it is important to store and package at the appropriate temperature to prevent caking during storage or long term bulk transportation. Caking can be a severe quality issue, resulting in breakage, fines, handling difficulties, a lower selling price and ultimately unhappy customers. The Solex Heat Exchanger is a simple piece of equipment designed for cooling fertilizer prills and granules. This technology combines mass flow of bulk solids with conventional plate heat exchanger design.
Several case studies show that a installed capital cost will be approximately 2/3 of the cost of a comparable fluid bed system. For the operation, a fluid bed cooler requires large horsepower fans. Additional energy requirements in a fluid bed system are for the air chiller, recompressing ammonia, and steam for the air pre-heater. The Solex Cooler eliminates the majority of this energy demand, with small horsepower requirements for the cooling water pump, bucket elevator and purge air system. Typically a urea granulation plant fitted with a Solex Cooler will save 4 –5 kW.h/tonne