Study On Nutrient Release And Nutritional Effect Of Compound (Mixed) Fertilizer Made By Different Processes

The compounding of function, fluidization and functionalization of fertilizer are important directions for fertilizer development, the recombination rate of fertilizer has reached to70%-80%in developed countries. Though compound fertilizer industry in our country started very late, fertilizer industry developed very fast. The recombination rate is32%in our country. With the rapid development of compound (mixed) fertilizer industry, process of compound fertilizer has been developed from single granulating method in80s to pulp method, aggregate method, melt granulation method, mixing method, coating method and so on. However, rapid development of fertilizer industry and agricultural demand are incoordinate. Lack assessment of agricultural effect with different process fertilizer products is the main problem. Research on production and application of compound (mixed) fertilizer is focus on the compound (mixed) fertilizer production technology and the effect of different formulations compound (mixed) fertilizer on increasing the yield of crops at home and abroad. There are little research on nutrient release characteristics, effects of applying different process compound fertilizer and environmental effects of compound fertilizers made by different processes. Therefore, combined field experiment and laboratory analysis to study the influence of compound (mixed) fertilizer (15-15-15) made by different processes on yield, growth and development, nutrient absorption and fertilizer use efficiency of corn.. Used the soil sylinders of aerobic culture-intermittent leaching methods to study the nutrient release features. The purpose of this research was to make sure the agricultural effects of compound (mixed) fertilizer made by different processes, provide useful evidence for choosing proper process and applying them with high production and high efficiency in agriculture.The results showed that there were obvious differences between compound (mixed) fertilizer made by different processes on nutrient release. The order of amount of nutrient release and rate of nutrient release was:Urea-formaldehyde process compound fertilizer<tower agglomeration process compound fertilizer<AZF process compound fertilizer<agglomeration process compound fertilizer<Spraying granulation process compound fertilizer<the mixed fertilizer. Urea-formaldehyde process compound fertilizer released nutrient slowly, the amount of nitrogen release was stable in the entire training period. On the second day of training,12.88%nitrogen released. According to the "slow controlled release fertilizer" industry standard, the initial nutrient release rate was less than15%which meant that this fertilizer had slow-release features. However, Spraying granulation process compound fertilizer, agglomeration process compound fertilizer and content of compound fertilizer released nutrient fast. On the second day of training, nutrient release rate reached to the peak, the amount of nitrogen release accounted for52.8%,59.6%and71.8%respectively. On the13th day of training, amount of nitrogen release accounted for more than80%. The amount of nutrient release and the rate of nutrient release in the prophase of cultivation of AZF process were significantly lower than that of mixed fertilizer. The rate of nitrogen, phosphorus, and potassium release rate was49.6%,29.8%and42.8%lower than that of mixed fertilizer respectively. Nutrient release peak of Urea-formaldehyde process and tower agglomeration process compound fertilizer granulation processes achieved later than other compound fertilizer which indicated that the nutrient release rate of urea formaldehyde technology, compound fertilizer granulation process of compound fertilizer tower was slowest, nutrient release rate of AZF process compound fertilizer was a bit faster. Nutrient release rate of spray granulation process compound fertilizer was equal to the rate of aggregate method technology compound fertilizer and mixed fertilizer. Different process (mixed) composite fertilizer nutrient about nitrogen, phosphorus, potassium release rules could be fitted by level1dynamic equation (y=No(1-e-kx)) and Logistic equation (y=k/(l+a*e-bx)). Useing level1dynamic equation to fit nitrogen and potassium release had the best effect, the next equation was Logistic equation.Field test results in2010showed that there was significant difference on increasing corn yield between compound fertilizer (15-15-15) made by different processes. Increasing corn yield effect of Urea formaldehyde technology compound fertilizer was the most significant, yield of this treatment was8.8%higher than that of mixed fertilizer. The better two fertilizers were the tower of compound fertilizer granulation process and AZF process compound fertilizer, yield of them was5.7%and5.8%higher than that of mixed fertilizer. Yield of spraying granulation process and agglomeration process compound fertilizer was equal to the yield of mixed fertilizer. The trend of increasing yield of compound fertilizer in2011was the same to that in2010, however, the increasing effect was less significant than that of2010and there was no significant difference between treatments. The reason might be that the test was positioning, nutrient left in the soil in2010influenced the effect of fertilizer in2011.Nutrient release and supply, the absorption and utilization of nitrogen, potassium and phosphorus of corn was significantly different between compound fertilizer made by different processes. NPK nutrient release of Urea formaldehyde technology, towers granulating process and AZF process compound fertilizers was slower than other process while it released fast during the later period and the amount of release was also lager which promoted the absorption of nutrient of corn in huge bellbottom and filling stage, promoted the dry matter accumulation in the late growth stage of corn, increased the Hundred-seed weight and the number of kernels, as a result, increased the yield of corn and fertilizer use efficiency. Compared with mixed fertilizer, the amount of nitrogen absorption of tower of granulating process and AZF process compound fertilizer was4.9%and19.8%higher than that of mixed fertilizer in Bell-mouthed stage. The amount of phosphorus absorption was2.7%and12.6%higher than that of mixed fertilizer. The amount of nitrogen, potassium and phosphorus of Urea formaldehyde technology compound fertilizer was3.91%,0.7%and4.2%higher than that of mixed fertilizer in filling stage of corn respectively, the Hundred-seed weight increased by1.7%,1.4%and3.0%in the late stage of corn, the number of kernels increased by6.1%,3.9%and2.3%. The utilization ratio, agricultural efficiency, nutrient partial productivity and harvest index of urea formaldehyde technology, towers granulating process compound fertilizer and AZF process compound fertilizer were better than other technology. Phosphorus utilization rate was21.2%,19.6%and22.7%under three processes which was8.0%,0.1%and15.8%higher than blend fertilizer. Utilization rate of potassium under three processes were43.0%,46.3%and50.8respectively and38.8%,63.9%and49.4%higher than that of blend fertilizer. NPK nutrient release of compound fertilizers with Spraying granulation process and agglomeration process and blend fertilizer was fast, corn needs less fertilizer in the early stage of growth, fertilizer was easily flown away by the rain which led to low utilization ratio of nutrient uptake, influenced corn kernels, decreased dry matter accumulation and Hundred-seed weight, as a result, yield of corn decreased.. Therefore, choosing compound fertilizers with slow release features for corn and other grain crops which need long time for growing could benifical to growth of crops. It could increase the absorption and utilization of nutrient, finally increase the yield of crops. In this test, urea formaldehyde technology and towers granulating process and AZF process of compound fertilizer had the best effects on achieving high yield and high efficiency utilization of fertilizer.