Preparation Organic Multi-Fertilizer Contain Silicon From Ash And Crop Straw

Silicon fertilizer is a new mineral fertilizer of high quality, high efficiency and no poison. At present, the silicon fertilizer generally contains very low soluble silicon content, and its price is too high. So, it is difficult to be extensively used. If the problem of how to increase the soluble silicon content can be solved, and its price can be down, the application of silicon fertilizer will be unfolded the wide foreground.This thesis introduced a new way of using activated silicon compound as a useful element added to organic fertilizer; other useful elements, such as K, was added or existed in the fertilizer essentially. So, when this organic fertilizer used, activated silicon, N, and K are imposed simultaneously, which will increase the crop's yields and farmer's income.In the thesis, organic fertilizers were produced from two solid wastes, viz. coal ash and crop straw. While reusing the ash and straw, this thesis could make contribution to the sustainable development of agriculture.In this thesis, the effects of the amounts of straw and KOH on silicon conversion, and the reaction time were meticulously tested by using orthogonal test at the initial time. The results showed: Hydrogen peroxide can promote the hydrolysis of crop straw but can't promote the conversion of silicon, and the effect of K₂CO₃ on the silicon conversion was not very evident, so, in the later tests, KOH solution was only considered to be used in hydrolyzing of crop straw. Conditions testing showed: With the increasing amounts of straw and KOH added, and with the protracting of reation time, the total amount of effective silicon was gradually increasing in the fertilizer. Considering the later operation, the optimized amounts of these two materials were selected. Additives tests indicated: Many additives were no use in increasing the silicon transformation, only seldom additives could increase the effective silicon content in fertilizers, and the effects were not very noticeable. So, their amounts added could be determined according to the actual situation.To determine the optimum value of all the factors, a series of single-factor tests had been done in this thesis. Temperature test showed increasing total effective silicon content in fertilizer with the increasing of reaction temperature gradually. Granularity tests indicated that the smaller size of raw materials, the higher total effective silicon content can be obtained in the fertilizer. And the optimized value of materials could be selected according to the change curve of them. In boiling conditions, the effective silicon contents in the fertilizers were increasing at the beginning then decreasing with the increasing amounts of straw and the optimum value of crop straws were selected; and with the increasing amount of KOH, the content of effective silicon in...