熔融造粒腐植酸尿素的缓释性能研究

运用碱处理风化煤得到水溶性腐植酸和沉淀混合物以及未处理的风化煤细粉（80目）分别与熔融尿素混合造粒，制得3种类型的腐植酸尿素产品，利用土柱淋洗方法研究不同腐植酸尿素产品的缓释性能。结果表明，除添加10%的未处理风化煤处理外，其余腐植酸尿素产品与普通尿素相比，均表现出具有氮缓释性能。其中，以添加水溶性腐植酸的产品缓释性最强；且当水溶性腐植酸与尿素比例为3∶7时，肥料的缓释效率最高。在本试验条件下，风化煤类腐植酸熔融造粒工艺下制成腐植酸复合尿素的缓释性能，与添加腐植酸的数量呈正相关；水溶性腐植酸添加比例与腐植酸复合尿素缓释性能相关性较低。3种类型的腐植酸复合尿素，以添加水溶性腐植酸的肥料质量最稳定。对风化煤进行活化后提取水溶性腐植酸，适量添加到熔融尿素中进行造粒，可生产出具有较好缓释性能的腐植酸尿素产品。

Study on slow release property of melting granulating humic acid urea

Weathering coal was treated with alkaline to get water soluble humic acid and deposition. Weathering coal, humic acid and deposition were compounded with melted urea respectively to produce the three kinds of compound ureas. Slow release properties of the ureas were studied by using the nitrogen soil leaching method. The results show that nitrogen release capacities of all compound ureas are slow except for the urea of adding 10 percent weathering coal, and the release capacity of urea of adding humic acid is lowest. The slow release efficiency of the compound urea of adding 30 percent humic acid is the highest. The slow release capability of weathering coal are different among three kinds of compound ureas, and there is a positive correlation between the slow release capability and the adding amount of humic acid. However, there is poor correlation between the slow release capacity and humic acid adding percent. The compound urea of adding water soluble humic acid has stable quality as a fertilizer. To use water soluble humic acid extracted from weathering coal, and introduce a suitable proportion of the acid and urea could produce humic acid compound urea with a better slow release property.