介绍用磷铁尾矿、硫酸、尿素直接加工成含有缓释作用的氮磷钾硫多元粒状复合肥,没有磷石膏排放。该工艺可处理反应活性较低的磷矿。产品对水稻、花生、玉米等作物经大田试验,获得较好的增产效果。产品经XRD物相分析,尿素与石膏形成了新结构,尿素降溶,石膏增溶,是一种具有较好应用前景的新复合肥料。 Introduced with phosphorus iron tailings, sulfuric acid, urea directly processed into a slow release of N, P and K sulfur granule compound fertilizer, no phosphogypsum emissions. The process can deal with less reactive phosphate rock. Products of rice, peanuts, corn and other crops tested in the field, get a better yield. XRD phase analysis of the product, urea and gypsum formed a new structure, urea solution, gypsum solubilization, is a promising new compound fertilizer.