养猪场沼渣制备包膜缓释肥理化性质表征

文章以分散式养猪场沼渣为应用研究对象,以8%聚乙烯醇为包膜材料,改性斜发沸石为肥料载体和缓控释材料调理剂,通过添加不同沸石量制备3种复混包膜缓释肥。利用红外光谱、扫描电镜及三维荧光对3种缓释肥的进行表征。结果表明:添加改性沸石的复混包膜肥除了增加显著的沸石红外特征谱外,其余红外光谱图差异不明显,表明添加沸石对有机质(富里酸和腐殖酸)结构和化学键型并未产生明显的影响,即不影响沼渣理化性质;添加改性沸石可以使聚乙烯醇完整的覆盖在肥料表面,膜壳更加平整光滑,膜层更加致密;三维荧光光谱显示复混包膜肥Ⅰ浸出富里酸和腐殖酸浓度最大,复混包膜肥Ⅲ浓度最低,表明添加沸石有减缓肥料养分释放的效果。该研究对于利用养猪场沼渣制备包膜缓释肥有一定的参考价值。

Characterization of Physicochemical Properties of Coated Slow-release Fertilizer Prepared from Pig Farm Biogas Residue

In this paper,the biogas residue of pig farm was used to produce slow-release fertilizer by 8%polyvinyl alcohol as the coating material,modified clinoptilolite as the fertilizer carrier and release controlling conditioner.By adding different amounts of clinoptilolite,three kinds of compound coated slow-release fertilizers were prepared.The three fertilizer structures were characterized by infrared spectroscopy,scanning electron microscope and three-dimensional fluorescence.The results showed that the adding of clinoptilolite except made the coated fertilizer increase the infrared characteristic spectrum of clinoptilolite,the other infrared spectra were not significantly different,indicating that the addition of clinoptilolite had no obvious effect on the structure and chemical bond of organic matter(fulvic acid and humic acid),that is,it does not affect the physicochemical properties of biogas residue.The addition of modified clinoptilolite could make the polyvinyl alcohol completely cover the surface of the fertilizer,and the membrane shell was smoother,the membrane layer was denser.The three-dimensional fluorescence spectrum showed that the concentration of fulvic acid and humic acid was the highest in compound coated fertilizer I,and that was the lowest for compound coated fertilizer III,indicating that the addition of clinoptilolite had the effect of slowing the release of fertilizer nutrients.