Characterization and Application

Characteristics of Ammonium Nitrate and the Necessity of Modification Fertilizer grade ammonium nitrate contains 33% to 34% nitrogen (N) and is a commonly used nitrogen fertilizer species in Europe, North America and some countries in temperate regions. Evaluated from the crop nitrogen nutrition on the demand for fertilizer, ammonium nitrate has the advantages of fast fertilizer effect, can simultaneously supply ammonium and nitrate two different forms of nitrogen source, which is undoubtedly beneficial to the growth of many crops. A large number of application facts have shown that, in addition to rice and a few other crops grown in paddy fields, the majority of crops, especially fruit trees, melons and vegetables, tobacco and other cash crops in dry crops prefer ammonium nitrate. However, to evaluate the chemical characteristics of fertilizer, ammonium nitrate is a very soluble in water, with strong hygroscopicity, caking and flammable and explosive nitrogen fertilizer varieties. These characteristics not only bring great difficulties in agricultural use, but also determines the ammonium nitrate in storage, transportation, if not properly managed, will cause fire or explosion. In fact, many countries in the world, including China, have had major accidents caused by ammonium nitrate. For this reason, China has banned ammonium nitrate into the fertilizer market. In recent years, with the expansion of irrigation and fertilization area, the demand for agricultural ammonium nitrate has increased. Some producers will improve its performance and quality as the goal of their efforts, and modified ammonium nitrate products have appeared on the market. In the way of technical modification, the following three types of approaches are used: first, the production of granular ammonium nitrate, and before granulation to add low hygroscopicity stabilizers or add insoluble inert substances, such as bone meal, phosphorite powder, dolomite, kaocenite and diatomaceous earth, etc.; second, the use of film-forming agent, ammonium nitrate particles coated with a layer of protective film on the surface of the air to isolate the air, the commonly used film-forming agent are vegetable oil, mineral oil, resin and paraffin, etc.; Third, appropriate change the composition of ammonium nitrate, the production of calcium ammonium nitrate, ammonium sulphur nitrate and phosphorus ammonium nitrate and so on. Earlier period in some European countries in the agricultural application of a single ammonium nitrate is expressly prohibited, some producers in ammonium nitrate to join ammonium sulfate, magnesium nitrate, potassium chloride, calcium nitrate, etc. made of compound fertilizer application. All of the above technical ways can improve the bad properties of ammonium nitrate. Calcium ammonium nitrate is a kind of ammonium nitrate modified products commonly used at home and abroad.

Characteristics and application of calcium ammonium nitrate Calcium ammonium nitrate (molecular formula NH4NO3+CaCO3) is made of molten ammonium nitrate and limestone powder mixed and molten at the ratio of 60:40, or manufactured with dolomite (a mixture of calcium carbonate and magnesium carbonate) and ammonium nitrate. It contains about 20% nitrogen. As for the detailed composition, there will be some differences in the products produced by different manufacturers. Now take De Potash Group Company Lion Horse brand calcium ammonium nitrate as an example, containing 27% nitrogen (N), of which 13.5% ammonium nitrogen, 13.5% nitrate nitrogen, 12% calcium (CaO), the average particle size of 3.0 to 3.6mm, the capacity of the weight of about 1.0 tons / cubic meter. The appearance color of calcium ammonium nitrate is usually gray or gray-brown particles, there are also green. In which ammonium nitrogen and nitrate nitrogen each accounts for half, containing much less nitrogen than the original ammonium nitrate. But it has small hygroscopicity, not easy to agglomerate, good dispersion and good physical properties.

Calcium ammonium nitrate contains a large amount of calcium carbonate, which is used as a chasing fertilizer on acidic soil with good effect and effect. When applied in paddy field, its fertilizer effect is slightly lower than ammonium sulfate with equal nitrogen amount, while when applied in dry land, the fertilizer effect is similar to ammonium sulfate. The cost of nitrogen in calcium ammonium nitrate is higher than that in common ammonium nitrate. Calcium ammonium nitrate is a physiologically neutral fertilizer as a low-concentration fertilizer, and long-term application plays a good role in soil properties. It can be used as a trailing fertilizer on cereal grain crops.

Nitrogen in calcium ammonium nitrate granules can be released more quickly, whereas lime dissolves slowly. The results of field trials on acidic soils have shown that calcium ammonium nitrate is agronomically effective and increases the overall level of yield.