Identification method of fertilizer:

1. Identification of color and shape

Different fertilizers have different colors and shapes. For example, urea is white or light yellow, with granular, needle-like or prismatic crystals. Ammonium sulfate is a white crystal. Ammonium bicarbonate is white or other variegated powder or granular crystals, and some manufacturers produce large-particle oblate ammonium bicarbonate.

ammonium chloride is white or light yellow crystal. Ammonium nitrate is white powdery crystal or white, light yellow spherical particles. Ammonia is a colorless or dark liquid. Lime nitrogen is grayish black powder. Calcium superphosphate is grayish white or light skin powder.

calcium superphosphate is dark gray, gray-white particles or powder. Calcium magnesium phosphate fertilizer is grayish brown or dark green powder. Calcium magnesium phosphorus potassium fertilizer is grayish brown or dark green powder. Phosphate rock powder is gray, brown or yellow drizzle powder.

nitrophosphate is gray-white particles. Potassium sulfate is white crystal or powder. Potassium chloride is white or reddish particles. Monoammonium phosphate is grayish white or dark gray particles. Diammonium phosphate is white or light yellow particles. Such fertilizers are genuine, otherwise, they can be regarded as fake and shoddy products.

2. odor identification

fertilizers with odor can be identified by odor. For example, the liquid with strong pungent ammonia smell is ammonia water; The fine particles with obvious pungent ammonia smell are ammonium bicarbonate.

The fine powder with sour taste is calcium superphosphate; What has a special foul smell is lime nitrogen. Ammonium sulfate is slightly sour. If the smell of these fertilizers is not obvious, they are not genuine or fake and shoddy products.

3. Identification by hand

Put the tested fertilizer in the palm of your hand, hold it firmly or press it to rotate, and judge the fertilizer according to the feel. It is more effective to distinguish diammonium in the United States by this method. Grab a handful of fertilizer and hold it hard for several times, and the one that feels "oily" is genuine; The dry as before is likely to be fake and shoddy fertilizer upside down.

In addition, there are mainly phosphogypsum, calcium magnesium phosphate, waste cement slag, fly ash, etc. in the market, which can also be judged simply by "feeling".

For example, calcium superphosphate feels soft but not frivolous; Phosphogypsum feels spongy and dry; Waste cement is heavier than calcium superphosphate, and it is not greasy, spongy and dry, and there are hard cement residues.

4. Dissolution identification

Weigh l g of chemical fertilizer suitable for water dissolution test, put it in a clean glass tube (or glass, white porcelain bowl), add 1 m l distilled water (or clean cold boiled water), and shake it well to see its dissolution; All dissolved nitrogen or potassium fertilizer.

calcium superphosphate is soluble in water but has residue; Calcium superphosphate is soluble in water without residue or little residue; Ammonium bicarbonate is soluble in water but has a strong ammonia smell; It is lime ammonia that is insoluble in water, but has bubbles and the smell of calcium carbide.

5. Identification of burning

When the fertilizer sample is heated or burned, the fertilizer can be identified from the flame color, smoke smell and residue. Such as: nitrogen fertilizer-ammonium bicarbonate, directly decomposed, producing a large number of white smoke, with strong ammonia smell and no residue.

The direct decomposition or sublimation of ammonium chloride produces a lot of white smoke, which has a strong ammonia smell and sour taste, and there is no residue; Urea can melt quickly, emit white smoke, and burn in a charcoal fire, or when a glass sheet is exposed to white smoke, a layer of white crystals can be seen on the glass sheet.

ammonium nitrate does not burn, but melts and boils, giving off smoke with ammonia smell. For example, phosphate fertilizer-calcium superphosphate, calcium magnesium phosphate, phosphate rock powder and so on have no change on red charcoal; Bone meal quickly turns black and gives off a burnt smell.

For example, potassium fertilizer-potassium sulfate, potassium chloride, potassium magnesium sulfate, etc. do not change on red charcoal, making a crackling sound. For example, the combustion of compound fertilizer is closely related to its raw materials. When there is ammonia nitrogen or amide nitrogen in its raw materials, it will give off a strong ammonia smell and there are a lot of residues.