Preserving potash COATING SOLUTIONS FOR POTASH FERTILIZER STORAGE AND TRANSPORT WRITTEN BY ANAND SUNDARARAMAN PHD, TECHNICAL MANAGER OF CROP NUTRITION AT ARKEMA Annually, millions of tons of potash
decreases and temperatures
dust complicates handling and
fertilizer products are exported
cool, re-crystallization leads to
land distribution, as it can become
globally, necessitating intricate
the formation of crystal bridges,
airborne during application in
logistics for transport and storage.
creating salt bonds that bind
the field. Consequently, it leads
This operation encompasses
granules together. These lumps
to uneven nutrient distribution
prolonged storage of potash
and agglomerates typically form
and potential health and safety
within facilities and transfer under
in fertilizer storage facilities or
concerns for users.
non-controlled environmental
because of exposure to harsh
conditions. Bulk potash transport
environmental conditions during
primarily leverages rail cars and
transit. The existence of solid
maritime vessels in combination
clumps within the fertilizer adds
with conveyor belts.
complexity to the handling
One prevalent issue during conventional storage and transportation is the frequent occurrence of potash fertilizer agglomeration, often referred to as “caking”. Caking arises primarily
process during loading and transit. Furthermore, these lumps can impede equipment spreading,
It is important to note that the phenomenon of moisture accumulation within bulk potash occurs at the air-potash interface throughout various stages, commencing with mining processing and persisting until the final application of potash to
leading to uneven nutrient
the soil in conjunction with other
distribution and increased wear on
fertilizers and additives. Figure 1
the equipment.
illustrates the effect of standard potash (KCl) fertilizer after
due to cyclical fluctuations in
In addition, the agglomerated
humidity, influenced by day-to-
fertilizer tends to generate
night temperature changes. When
dust during packaging or
humidity increases, moisture
transportation due to the
Although various methods can
either condenses from the air
mechanical abrasion caused by
be adopted to address these
or migrates out of the granules,
the movement of the fertilizer
challenges, applying a protective
initiating the dissolution of the
particles and/or the migration of
coating on granular fertilizers
fertilizer. Conversely, as humidity
moisture through the fertilizer. This
emerges as an effective strategy.
66 PotashWorks 2024
exposure to 85 per cent RH at 30°C for eight hours.