一、引言为了实现农业现代化、大幅度地提高农作物的产量,必须进行科学施肥,而科学施肥向化肥工业提出的最基本要求之一,就是要使N、P、K化肥的生产比例适宜于农业生产发展的需要,以及发展含有多种营养元素的高浓度混合、复合肥料。世界各国普遍重视的这一原则,不仅有农业上的因素, I. INTRODUCTION In order to realize the modernization of agriculture and greatly increase the output of crops, scientific fertilization must be carried out. One of the most basic requirements put forward by the scientific fertilization to the fertilizer industry is to make the proportion of N, P and K fertilizer suitable for agriculture The need for production development, and the development of high concentrations of mixed and compost fertilizers containing various nutrients. This principle, which is universally regarded by all countries in the world, has not only the agricultural factor,