论文部分内容阅读
尿素是我国重要的氮素化肥之一。由于某些厂家在尿素造粒过程中温度失控(>133℃),能分解出氨和缩二脲 133℃ 2H_2NCONH_2→(CONH_2)_2=NH+NH_3↑ △国内外公认,缩二脲含量过高时,对农作物有毒害作用。一般要求缩二脲含量不超过1.5％,农用二级品应不高于1.8％。用作根外追肥的尿素中缩二脲含量不超过0.5％。 我市盐亭县1986年播种冬小麦时,由于施用了超标缩二脲的尿素作为基肥,导致16,700亩小麦严重缺苗,并出现大量白化苗(图1),造成粮食减收167万公斤,经济损失66.8万元。
Urea is one of the important nitrogen fertilizers in our country. Due to the temperature control (> 133 ℃) of urea granulation process in some manufacturers, ammonia and biuret can be decomposed 133 ℃ 2H_2NCONH_2 → (CONH_2) _2 = NH + NH_3 ↑ △ It is recognized at home and abroad that the biuret content is too high When toxic to crops. General requirements biuret content of not more than 1.5%, agricultural secondary products should not be higher than 1.8%. Urea biuret for top dressing should not exceed 0.5%. Yanting County in 1986 when we planted winter wheat, due to the application of biuret urea as a base fertilizer, resulting in a serious shortage of 16,700 acres of wheat seedlings, and the emergence of a large number of albino seedlings (Figure 1), resulting in 1.67 million kilograms of grain, the economy 668,000 yuan loss.