Chapter 6: Fertilizer Formulation, Storage, and handling Three systems available: Bulk Blend or Prescription mix nutrients. Direct application of homogeneous product. Fluid fertilizer (from clear liquid solutions to suspensions

Bulk Blend or Prescription mix nutrients May use homogeneous products as part of the blend, along with other granular, prilled, or crystalline fertilizer materials to meet desired nutrient requirements. Should use uniformly sized products to minimize segregation in storage & handling.

Direct application of homogeneous product. Benefit is that each pellet has the same chemical make up. Can be in bulk form or ordered in bagged form.

Fluid fertilizer Its main benefits are the ease of handling, uniform composition, and compatibility with crop protection chemicals. Suspension can have a twice the nutrient content than clear. Large amounts of secondary nutrients and micronutrients can be used in suspensions.

Formulations Bulk/Bagged Blends Are physical mixes of two or more dry products. Examples of products used are: ammonium nitrate, ammonium sulfate, urea, diammonium phosphate, monoammonium phosphate, potassium materials, and elemental sulfur.

Bulk/Bagged Blends Problems Segregation or separation of one component or raw material from another. Segregation may happen when storing finished products in cone shape piles or when loading in a truck or trailor.

Homogeneous product problems One problem is that specific grades are not produced to meet every soil or plant condition.

Fluid fertilizer problems (Clear) Although high N-P grades can be produced, the addition of other fertilizer material raises the salting-out temperature, thus limiting the nutrient content. As the salting-out temperature is raised. The solution becomes unstable.

Fluid fertilizer problems (Suspension) Applications can be hampered by the clogging of the nozzles Failure to agitate the tank

Storage and Handling Refer to Table 6-3 for humidity and temperature data on each fertilizer.

Storage and Handling Ammonium nitrate Keep it away from open flames Avoid contaminating it with foreign matter. Sweep up & dispose of all contaminated material. Do not store it in close proximity to steam pipes or radiators. Keep it separate from other materials stored in the same warehouse, especially combustible organic materials and urea.

Urea Keep it away from open flames Avoid contaminating it with foreign matter. Sweep up & dispose of all contaminated material. Do not store it in close proximity to steam pipes or radiators. Keep it separate from other materials stored in the same warehouse, especially combustible organic materials and ammonium nitrate.

Why keep the two apart? Urea is less hygroscopic than ammonium nitrate. It will absorb moisture at 18% relative humidity if stored with ammonium nitrate.

Ammonium sulfate Easy to store due to its high critical relative humidity of 79% at 860F It is corrosive, so store in concrete or wood structures.

Phosphorus and potassium materials By the most part they require no specialized storage. Use common sense. It is corrosive, so store in concrete or wood structures.

Fluid Materials Anhydrous ammonia Potentially hazardous due to the high pressures that it is stored under.

Aqua ammonia Since ammonia vapor is constantly leaving the solution a pressure-vacuum relief value must be installed on storage tanks.

Urea-ammonium nitrate solutions Store in mild steel or poly tanks with appropriate secondary containment. Brass, copper, or galvanized materials should not be used for handling systems.

Ammonium nitrate solution Store in mild steel or poly tanks with appropriate secondary containment. ***NOTE that this is more corrosive to mild steel. Brass, copper, or galvanized materials should not be used for handling systems.

Urea solutions Store in mild steel or poly tanks with appropriate secondary containment. Brass, copper, or galvanized materials should not be used for handling systems. Have a higher salt-out temperatures.

Phosphoric & superphosphoric acids Corrosive acids that require rubber or plastic lined stainless steel or plastic tanks and plumbing are required. A silica-gel breather should be installed to prevent moisture from entering the tank due to superphosphoric when it absorbs moisture produces a more corrosive acid.

Cont. External jacketing or steam tracing will prevent freezing in long lines. Prevent contact with skin and eyes due to the fact that it is a strong dehydrating agent that can cause blistering.

Clear liquid & fluid suspensions If neutral solutions – mild steel or poly storage can be used.

Sulfuric Acid Storage tanks must be vented to maintain the tanks atmospheric pressure. When added to water it becomes more corrosive and the use of non-reactive liners are suggested. Should not be stored near other organic materials. It may cause ignition.

Urea-acid combinations Storage tanks must be vented to maintain the tanks atmospheric pressure. When added to water it becomes more corrosive and the use of non-reactive liners are suggested. Should not be stored near other organic materials. It may cause ignition.

Sulfur materials for formulation of liquids These types of fertilizers are corrosive. Thus one should use storage facilities that are not degraded when they come in contact with these substances.