Urea.

Fertilizer Urea

Urea, a white crystalline solid containing 46% nitrogen, is widely used in the agricultural industry as an animal feed additive and fertilizer Here we discuss it only as a nitrogen fertilizer. Export of Urea/ Seller Of Urea or Manufacture, they still follow the same procedures.

Physical Forms of Urea Commercially, fertilizer urea can be purchased as prills or as a granulated material. In the past, it was usually produced by dropping liquid urea from a “prilling tower” while drying the product. The prills formed a smaller and softer substance than other materials commonly used in fertilizer blends. Today, though, considerable urea is manufactured as granules. Granules are larger, harder, and more resistant to moisture. As a result, granulated urea has become a more suitable material

for fertilizer blends.

  
  • 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.

UREA DETAILS:

Urea, a white crystalline solid containing 46% nitrogen, is widely used in the agricultural industry as an animal feed additive and fertilizer Here we discuss it only as a nitrogen 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.

Urea Losses to the Air

Urea breakdown begins as soon as it is applied to the soil. If the soil is totally dry, no reaction happens. But with the enzyme urease, plus any small amount of soil moisture, urea normally hydrolizes and converts to ammonium and carbon dioxide. This can occur in 2 to 4 days and happens quicker on high pH soils. Unless it rains, urea must be incorporated during this time to avoid ammonia loss. Losses might be quite low in the spring if the soil temperature is cold. The chemical reaction is as follows:

CO(NH2)2 + H2O + urease 2NH3 +CO2
(urea)

The problem is the NH3, because it’s a gas, but if incorporated the NH3, acts the same as incorporated anhydrous ammonia. Also, half of 28% liquid N is urea and the same thing happens with this half as with regular urea.

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.

Table 1. Percent of surface-added urea volatilized as ammonia at different temperatures and days on the surface.

Temperature (F)
Days 45 degrees 60 degrees 75 degrees 90 degrees

(% of added N volatilized)
0 0 0 0 0
2 0 0 1 2
4 2 2 4 5
6 5 6 7 10
8 5 7 12 19
10 6 10 14 20

Data abstracted from curves in SSSP 24, pages 87-90, 1960. Urea was added on a silt loam soil at 100 lbs N.

 

Table 2. Percent of surface-added urea volatilized as ammonia at various soil pH levels and days on the surface.

Soil pH
Days 5.0 5.5 6.0 6.5 7.0 7.5

(% of added N volatilized)
0 0 0 0 0 0 0
2 0 0 0 0 1 5
4 1 2 5 10 18 20
6 4 5 7 11 23 30
8 8 9 12 18 30 33
10 8 10 13 22 40 44

Fall Application Comparisons

Urea can be readily nitrified—that is, converted to nitrate (NO3)— even when applied late in the fall, and can be quite susceptible to denitrification or leaching the following spring. Anhydrous ammonia (AA) applied in the fall does not nitrify as quickly, due to the stunting of microorganisms in the AA application band.

A two-year study conducted at Waseca compared late-October applications of both AA and urea for continuous corn (Table 3). These data show a 6 bu/A advantage for AA over urea when applied in the fall without a nitrification inhibitor. But when N-Serve was added, a 16 bu/A advantage was shown with AA. This indicates that the inhibitor has a better degree of contact with the AA mix than is possible with urea.

Spreading of Urea

Urea can be bulk-spread, either alone or blended with most other fertilizers. It is recommended that the spreading width not exceed 50 feet when combined with other fertilizer materials.

Urea often has a lower density than other fertilizers with which it is blended. This lack of “weight” produces a shorter “distance-of-throw” when the fertilizer is applied with spinner-type equipment. In extreme cases this will result in uneven crop growth and “wavy” or “streaky” fields.

Blending Urea with Other Fertilizers

Urea and fertilizers containing urea can be blended quite readily with monoammonium phosphate (11-52-0) or diammonium phosphate (18-46-0).

Urea should not be blended with superphosphates unless applied shortly after mixing. Urea will react with superphosphates, releasing water molecules and resulting in a damp material which is difficult to store and apply.

Fluid Urea

Uniformity of particle size is important with dry solid urea, whether applied directly or in blended formulations. Some imported urea appears to be below U.S. quality standards on granule uniformity. Dissolving urea and marketing the liquid solution is an attempt to overcome this lack of uniformity and still take advantage of the favorable urea price.

The liquid mix of urea and ammonium nitrate (UAN 28% N) has been on the market for a long time. The characteristics of this solution, however, are not the same as when urea alone is dissolved in water. A solution of 50% urea by weight results in 23-0-0 and has a salting-out temperature of 60 degrees F. In order to store and handle liquid urea during cooler temperatures, the nitrogen concentration must be lowered to reduce salting problems. There are several possible formulations that can be used for this, such as adding small amounts of ammonium nitrate, ammonium sulfate, or anhydrous ammonia.

Research, particularly on liquid urea, is very limited. Generally, where dry urea functions successfully, the fluid urea should perform equally well and may have the advantage of better uniformity over some dry urea sources.

SPECIFICATION

NPK 15-15-15 (GRANULE) fertilizer

NPK 15-15-15 is high effective granular compound homogeneous fertilizer, including all elements necessary for development of plants (nitrogen, phosphorus and potassium). All substances contained in the fertilizer are soluble in water. 
Appearance :             pink-grey granules. 
Origin :                       Europe/Russian/Egypt

Parameter

15-15-15

Total nutrients content  (N+Р2О5+К2О+S), %, min

45

Total nitrogen content, %, min

15±1

Total phosphates content, %, min

15±1

Total potassium content (in terms of K2O), %, min

15±1

Sulphate Sulfur as S, %

8 ± 1

Granulometry, % mass portion of granules sized

less than 1 mm, %, max

3

from 2 to 4 mm, %, min

90

less than 6 mm, %

100

Static strength of granules, MPa (kgf/cm2), min

3,0 (30)

Friability, %, min

100

Vietnam considers exporting urea, from 2012

VietNamNet Bridge – Vietnam, which once had to rely on urea imports to develop agriculture, now can satisfy the domestic demand itself. Especially, it is considering exporting urea from this year.

The Fertilizer Association of Vietnam FAV has said that from 2012, Vietnam would become self-sufficient in urea, when the 800,000 ton per annum Ca Mau Fertilizer Plant of the Vietnam National Oil and Gas Group (PetroVietnam) and the 560,000 ton per annum Ninh Binh Fertilizer Plant of the Vietnam Chemical Group become operational, raising the total capacity to 2.36 million tons, double that of 2011.

Meanwhile, it is estimated that the demand for urea would be 1.8 million tons only in 2012. As such, Vietnam now can not only satisfy its demand, but also has products in excess for export. With the current production capacity, the supply may be higher by 560,000 tons per annum than the demand.

Meanwhile, analysts have forecast that the domestic urea output would keep rising. The output would exceed the 3 million ton threshold by 2015. The Ha Bac Fertilizer Plant is expanding the production to increase the capacity from 200,000 tons to 500,000 tons by 2015. Meanwhile, Cong Thanh group is also considering making nitrate from coal dust with its 560,000 ton per annum plant located in Tinh Gia district of Thanh Hoa province.

According to FAV, exporting fertilizer is the solution for Vietnamese manufacturers to ease the competition on the domestic market. However, in the export markets, Vietnamese products would have to compete fiercely with the products from China, Thailand, the Middle East and Russia.

Analysts have pointed out that Africa proves to be a good market for Vietnamese fertilizer exporters. However, there are latent risks on the market, because African banks in the countries do not ensure the payment. Therefore, if the government of Vietnam can sign the agreement on payment guaranteeing with the African governments, the exports to the markets would increase very rapidly.

According to FAV’s Secretary General Nguyen Dinh Hac Thuy, the fertilizer price much depends on the coal and gas prices, and the apatite prices as well, because these are the input materials for fertilizer production.

Therefore, Thuy has called on the fuel suppliers to apply reasonable policies on fuel prices, and called on the Ministry of Finance to set up reasonable tax policies in order to facilitate fertilizer exports.

According to the Ministry of Agriculture and Rural Development MARD, Vietnam would need some 9.8 million tons of fertilizer of different kinds in 2012. This includes 3.5 million tons of NPK, 2 million tons of urea, 1.8 million tons phosphate, 950,000 tons of DAP, 920,000 tons of kali and 710,000 tons of SA.

Of these products, Vietnam will be self-sufficient in NPK, phosphate and urea by 2012. Meanwhile, as for DAP, the 330,000 ton Dinh Vu DAP Plant in Hai Phong City can only satisfy 35 percent of the total demand, while the other 65 percent will still be fed by imports.

The Vietnam Chemical Group is speeding up the project on building a DAP plant in Lao Cai province which has the same capacity with the Dinh Vu’s plant.

As such, after some more years, the DAP imports would decrease significantly. Meanwhile, Vietnam will still to import SA and kali, because no domestic plant can make these two kinds of products.

Vietnam now has everything needed to make ammoniac, the material for SA production. Meanwhile, if the project on exploiting and processing mine salt in Laos is implemented, Vietnam will be able to produce kali for the domestic market.

Source: TBKTVN

 

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