- Product : Urea 46% N
- Categories : Mineral Fertilizers
- Origin : Azerbaijan, Russia
- Loading Ports : Several options
- Acceptability :
Urea 46% N
Urea, also known as carbamide, is an organic compound with chemical formula CO(NH2)2. This amide has two –NH2 groups joined by a carbonyl (C=O) functional group.
Urea serves an important role in the metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals.
It is a colorless, odorless solid, highly soluble in water, and practically non-toxic (LD50 is 15 g/kg for rats). Dissolved in water, it is neither acidic nor alkaline. The body uses it in many processes, most notably nitrogen excretion.
Urea is an inexpensive form of nitrogen fertilizer with an NPK (nitrogen-phosphorus-potassium) ratio of 46-0-0. Synthetic urea is manufactured with anhydrous ammonia.
Although urea often offers gardeners the most nitrogen for the lowest price on the market, special steps must be taken when applying urea to the soil to prevent the loss of nitrogen through a chemical reaction.
Urea was first produced industrially by the hydration of calcium cyanamide but the easy availability of ammonia led to the development of ammonia/carbon dioxide technology. This is a two-step process where the ammonia and carbon dioxide react to form ammonium carbamate which is then dehydrated to urea.
In the process, ammonia and carbon dioxide are fed to the synthesis reactor which operates around 180-210oC and 150 bar pressure. The reaction mixture containing ammonia, ammonium carbamate, and urea is first stripped of the ammonia and the resultant solution passes through a number of decomposers operating at progressively reduced pressures. Here the unconverted carbamate is decomposed back to ammonia and carbon dioxide and recycled to the reactor.
The urea solution is concentrated by evaporation or crystallization, and the crystals can be melted to yield pure urea in the form of prills or granules. Prills are made by spraying molten urea from the top of a high tower through a counter-current air stream. Granular urea is formed by spraying molten urea into a mixture of dried urea particles and fines in a rotating drum.
Urea processes fall into two categories: external solution recycle systems, and internal solution stripping systems. In the former, energy is saved by high carbon dioxide conversion rates while the latter reduces net energy requirements by optimizing heat recovery.
- Product : Di-Ammonium Phosphate
- Categories : Mineral Fertilizers
- Origin : Azerbaijan, Russia
- Loading Ports : Several options
- Acceptability :
Di-Ammonium Phosphate - DAP
It is the most widely used phosphorus fertilizer worldwide. It is made from two common constituents in the fertilizer industry, and its relatively high nutrient content and excellent physical properties make it a popular choice in farming and other industries.
Ammonium phosphate fertilizers first became available in the 1960s, and DAP rapidly became the most popular in this class of products. It is formulated in a controlled reaction of phosphoric acid with ammonia, where the hot slurry is then cooled, granulated and sieved. DAP can be handled and stored well. The standard nutrient grade of DAP is relatively high, at 18-46-0, so fertilizer products with lower nutrient content may not be labeled DAP.
DAP fertilizer is an excellent source of P and nitrogen (N) for plant nutrition. It is highly soluble and thus dissolves quickly in soil to release plant-available phosphate and ammonium. A notable property of DAP is the alkaline pH that develops around the dissolving granule.
The ammonium present in DAP is an excellent N source and will be gradually converted to nitrate by soil bacteria, resulting in a subsequent drop in pH. Therefore, the rise in soil pH surrounding DAP granules is a temporary effect. This initial rise in soil pH neighboring DAP can influence the micro-site reactions of phosphate and soil organic matter.
Di-Ammonium Phosphate also acts as a fire retardant. For example, a mixture of DAP and other ingredients can be spread in advance of a fire to prevent a forest from burning. It then becomes a nutrient source after the danger of fire has passed. DAP is used in various industrial processes, too, such as metal finishing. And, it is commonly added to wine to sustain yeast fermentation and to milk to produce cheese cultures.
- Product : Monoammonium Phosphate
- Categories : Mineral Fertilizers
- Origin : Azerbaijan, Russia
- Loading Ports : Several options
- Acceptability :
Monoammonium Phosphate - MAP
Monoammonium phosphate (MAP) is a widely used source of phosphorus (P) and nitrogen (N). It is made of two constituents common in the fertilizer industry and contains the most phosphorus of any common solid fertilizer.
The process for manufacturing MAP is relatively simple. In a common method, a one-to-one ratio of ammonia (NH₃) and phosphoric acid (H₃PO₄) is reacted and the resulting slurry of MAP is solidified in a granulator. The second method introduces the two starting materials in a pipe-cross reactor, where the reaction generates heat to evaporate water and solidify MAP. Other methods exist as well.
An advantage of manufactured MAP is that lower-quality H₃PO₄ can be used compared with other P fertilizers often requiring a more pure grade of acid. The phosphorus pentoxide (P₂O₅) equivalent content of MAP varies from 48 to 61 percent, depending on the amount of impurity in the acid. The most common fertilizer composition is 11-52-0.
MAP has been an important granular fertilizer for many years. It is water-soluble and dissolves rapidly in adequately moist soil. Upon dissolution, the two basic components of the fertilizer separate again to release ammonium (NH₄⁺) and phosphate (H₂PO₄⁻), both of which plants rely on for healthy, sustained growth. The pH of the solution surrounding the granule is moderately acidic, making MAP an especially desirable fertilizer in neutral- and high-pH soils. Agronomic studies show that, under most conditions, no significant difference exists in P nutrition between various commercial P fertilizers under most conditions.
MAP is used in dry chemical fire extinguishers commonly found in offices, schools and homes. The extinguisher spray disperses finely powdered MAP, which coats the fuel and rapidly smothers the flame.