Nitrogenous Fertiliser

Infobox on Nitrogenous Fertiliser
Example of Nitrogenous Fertiliser
Facts
Origin	-
Stowage factor (in m3/t)	-
Angle of repose	-
Humidity / moisture	-
Oil content	-
Ventilation	-
Risk factors	-

Nitrogenous Fertiliser

Description

Over the last few years various problems have been encountered, associated with coagulation and compaction of prilled nitrogenous fertilizer in bulk. The majority of fertilizer carried is in the form of urea, ammonium nitrate or sodium/potassium nitrate. The fertilizer can be shipped in 50 kg bags, in flexible intermediate bulk containers (FIBC) up to one tonne or in bulk for bagging on completion of discharge.

On arrival at the discharge ports it is not uncommon for the prilled fertilizer to be found in a compacted state. This condition may easily be identified if the product is in pure bulk form; however, it may not so easily be identified if carried in bulk bags or palletised bags.

Compaction or coagulation may occur prior to discharge due to one or more of the following reasons:

• Insufficient drying carried out prior to loading. If the product is dried utilizing a blown air system there should be sufficient volume of air to carry out the drying process.
• Insufficient anti-caking agent applied. If anti-caking agent is used it is most important that the correct application rate should be applied.
• Insufficient priming/curing time prior to loading. Anti-caking agents require time to act before loading or bagging.
• Loading/bagging in conditions of high humidity. During times of high humidity many prilled fertilizers become remarkably hygroscopic and will absorb moisture from the atmosphere.
• Water ingress during sea passage. This may occur either due to leaking hatches or ingress via the bilge system.
• Moisture due to condensation. If the passage is subject to variable temperatures, condensation may form on the ship’s structure and fall on to the cargo. Ventilation on passage may have to be considered but instructions should be sought from shippers.
• Natural compaction due to motion of the vessel whilst on passage.
  
  

The problems encountered by the farmers as end users may be listed as follows:

• Time factor:
  the time taken to break down the lumps manually to a free flowing state may greatly increase the time taken to spread a given acreage.
• Uneven spread rate:
  if the lumps are not completely broken down, blocking of the spreader outlet may occur, reducing the application rate or even cutting off the flow completely. This results in uneven spread of the product. Crop reduction may be a direct result.
• Spillage:
  a considerable amount of spillage may occur when large lumps drop into free flowing prills. This has an effect of increasing time taken and also wastage.
• Damage to machinery:
  the unexpected dropping of large lumps of product into hoppers may result in damage being occasioned to the hopper sides or distortion of the filter grid.
• Safety implications:
  various comments have been made to surveyors concerning this aspect. Where bags are suspended over the spreader hopper and the bottom of the bag slit to allow product to flow into the hopper, some party of the human body will of necessity be partially below the bag during this operation. If the bag is slit and the weight of the solid lump splits the bag further and suddenly drops, injury may result.
  
  

It should be pointed out that the compaction or coagulation does not impair the quality of the product once it has been broken down to a usable free-flowing condition. However, this saving is not sufficient to compensate farmers for the additional time taken to break down the lumps to a useable condition.

Late deliveries may aggravate the problems, forcing the farmers to accept the product rather than reject it and await fresh delivery.

Full information on this product is in the process of completion.