Study On Slow Release Effect And Fertilizer Efficiency Of Value-added Urea

At present, China urea utilization below 30%, not only resulted in substantial economic loss, but also serious harm to the environment. How to improve nitrogen use efficiency in agriculture be solved become a reality. Today, natural, pollution-free, easily degradable industrial waste and other material or develop new types of fertilizers have become popular. The test selected weathered coal, humic acid and monosodium glutamate factory waste of three organic materials, development of value-added urea products, through laboratory experiments and outdoor experiments explore the performance of its release, on soil properties and nitrogen use efficiency. The main results are as follows:1 With the density 2% KOH, withdraws 20min, from decency coal system high extraction rate humic acid; Carries on the pelleting experiment separately together with the decency coal and the monosodium glutamate factory waste liquid with the urea. The result indicated that the different organic matter anticipates the increase proportion, its fusing and the granulation effect had obviously different; Along with the humic acid and decency coal recruitment's increase, the fusing time lengthens gradually, the melt fluid tended sticks thickly, when the recruitment achieves 10%, the granulation was difficult; But the monosodium glutamate factory waste liquid displays the opposite effect, when the recruitment reached 10%, a grain of intensity reduced obviously.2 After traditional process urea fusing, the biuret content reaches as high as 3.43%, and time-consuming is 50min. The biuret reducing test indicated that when the additive amount used was 7%, not only obviously reduced the biuret content and the fusing time, moreover may maintain the good grain and a grain of intensity. After using the improvement the craft, according to the different organic material increase proportion, the most completion of three year mourning period for one's parents can under the fertilizer type:Decency coal class (1F and 5F), humic acid class (1H and 5H), monosodium glutamate factory waste liquid class (1T and 5T) and mix class (M).3 The value-added urea got good effect in reducing ammonia volatilization losses of urea and inorganic nitrogen leaching from the soil had a marked effect. At 15℃and 25℃, the high volume of weathered coal ratio of urea and ammonia volatilization category decreased 32.9% and 41.8%, followed by high levels of humic acid; other types of value-added urea reduction rate of 16.9%～40.5%; while value-added urea can significantly delayed the time of maximum value of ammonia volatilization. High levels of humic acid reduced the NH4+-N and NO3--N leaching capacity of the cumulative 18.5% and 14.5%, a significant effect; other value-added urea to reduced the rate at between 2.96%-8.89% and 3.63%-9.09%, respectively.4 The value-added urea enhanced the soil organic matter and the total nitrogen content, reduced the soil pH value, suppressed the soil urease activeness obviously; Obviously increased the content of SMB-C and the SMB-N, caused it to maintain the high content in the long time, and postponed the its peak.5 The value-added urea improved the corn the agronomic characters, the promotion crops' growth and the nitrogen use factor. The employment increment urea enhanced the corn and the rape output separately reached 3.42%～24.41% and 2.04%-28.7%; The value-added urea nitrogen use factor increased the scope on the corn and the rape separately between 1.3～10.5 and 0.73～6.05 percentage point, was good by the high quantity organic material increment urea effect, the monosodium glutamate factory waste liquid class was most superior, next for humic acid class and decency coal class.