Urea 46

Description

Urea (46% N)

This is the most concentrated solid nitrogen fertilizer and it is marketed in the prilled form. It is sometimes used for aerial top-dressing. In the soil, urea changes to ammonium carbonate which may temporarily cause a harmful local high pH. Nitrogen, as ammonia, may be lost from the surface of chalk or limestone soils, or light sandy soils when urea is applied as a top-dressing during a period of warm weather. When it is washed or worked into the soil, it is as effective as any other nitrogen fertilizer and is most efficiently utilized on soils with adequate moisture content, so that the gaseous ammonia can go quickly into solution. In dry conditions in the height of summer it is probably better to use ammonium nitrate. Chemical and bacterial action changes it to the ammonium and nitrate forms. If applied close to seeds, urea may reduce germination.

Urea 46, Main Specification

Normally Specification:

Specifications	Urea Prilled	Urea Granulated
Mass portion of nitrogen (N) on a dry basis, %min	46.2	46.2
Mass portion of biuret, %, max	1.0	1.0
Moisture (determined by Fischer method), % max:	0.5	0.5
Color	white	white
Static Strength	–	2.5 kgs/granule

Product free-flowing, free from dust and harmful substances Urea is a non-combustible, fire and explosion-proof substance

Granulometry

About the Granulometry:

Specification		Urea Prilled	Urea Granulated
Granulometry, %	2-5 mm	–	95
	1-4 mm	90	–
	less than 1 mm	–	2
	more than 6 mm	None	None

Urea is an inexpensive form of nitrogen fertilizer with an NPK (nitrogen-phosphorus-potassium) ratio of 46-0-0. Although urea is naturally produced in humans and animals, 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 is widely used in the agricultural sector both as a fertilizer and animal feed additive. The main function of Urea fertilizer is to provide the plants with nitrogen to promote green leafy growth and make the plants look lush. Urea also aids the photosynthesis process of plants.

Advantage of Fertilizer Urea

can be applied to soil as a solid or solution or to certain crops as a foliar spray.
Urea usage involves little or no fire or explosion hazard.
Urea’s high analysis, 46% N, helps reduce handling, storage and transportation costs over other dry N forms.
Urea manufacture releases few pollutants to the environment.
Urea, when properly applied, results in crop yield increases equal to other forms of nitrogen.
Incorporate urea for best use

Nitrogen from urea can be lost to the atmosphere if fertilizer urea remains on the soil surface for extended periods of time during warm weather. The key to the most efficient use of urea is to incorporate it into the soil during a tillage operation. It may also be blended into the soil with irrigation water. A rainfall of as little as 0.25 inches is sufficient to blend urea into the soil to a depth at which ammonia losses will not occur.

If properly applied, urea and fertilizers containing urea are excellent sources of nitrogen for crop production. After application to the soil, urea undergoes chemical changes and ammonium (NH4 +) ions form. Soil moisture determines how rapidly this conversion takes place.

When a urea particle dissolves, the area around it becomes a zone of high pH and ammonia concentration. This zone can be quite toxic for a few hours. Seed and seedling roots within this zone can be killed by the free ammonia that has formed. Fortunately, this toxic zone becomes neutralized in most soils as the ammonia converts to ammonium. Usually it’s just a few days before plants can effectively use the nitrogen. Although urea imparts an alkaline reaction when first applied to the soil, the net effect is to produce an acid reaction.

Urea or materials containing urea should, in general, be broadcast and immediately incorporated into the soil. Urea-based fertilizer applied in a band should be separated from the seed by at least two inches of soil. Under no circumstances should urea or urea-based fertilizer be seed-placed with corn.

With small grains, 10 lb. of nitrogen as urea can generally be applied with the grain drill at seeding time even under dry conditions.

disadvantage of Urea

Urea has several advantages, including cost per pound of nitrogen, higher nutrient density, and good handling and storage properties.

The biggest disadvantage is the potential for volatilization. This occurs when urea is surface-applied and converted to ammonium carbonate by urease.