Chinese name: 屎素
English name: urea
Quality Index:
Industrial urea quality indicators: (GB 2440 a 2001)
First-class index of qualified products
Appearance of white particles or crystallization
Total nitrogen (N) content (dry basis) mass fraction /% ≥ 46.3 46.3
Biuret content /% ≤ -0.50 1.00
Iron (Fe) content /% ≤ 0.0005 0.001
Alkalinity (NH3 content) /% ≤ O.015 0.030
Water insoluble content /% ≤ 0.01 O.04
Moisture /% ≤ 0.50 1.00
Particle size (φ0.8 ~ 2.5mm) /% ≥ 90 90

Agricultural Applications:
    Urea is a high concentration of nitrogen fertilizer, is a neutral quick-acting fertilizer, can also be used to produce a variety of compound fertilizers. In the soil does not leave any harmful substances, long-term use without adverse effects. Livestock can be used as feed for ruminants. However, granulation in the high temperature will produce a small amount of biuret, also known as biuret, the crop has inhibited. China's regulation of urea biuret fertilizer content should be less than 0.5%. Biuret content of more than 1%, can not do kind of fertilizer, Miao Fei and foliar fertilizer, urea content of other applications should not be too much or too concentrated.
    Urea is an organic nitrogen fertilizer, after the role of urease in the soil, hydrolysis into ammonium carbonate or ammonium bicarbonate, the crop can be absorbed and utilized. Therefore, urea should be applied 4 to 8 days prior to the fertilizer-needed period of the crop.