Preparation Organic Multi-fertilizer Contain Silicon From Coal Gangue/coal Ash And Crop Straw

In this thesis, the organic compound fertilizer containing silicon was studied by using coal gangue / fly ash and straw as main raw material. In achieving the reasonable use of waste solid, this study will also contribute to the sustainable development of agriculture.In preliminary test of the straw's hydrolysis, the amount of straw, the alkali amount and the timing of accession, reaction time and other factors were studied using orthogonal test. The results indicate that the hydrolysis rate is influenced by the reaction time, temperature; the amount of H₂O₂ added, and the amount of KOH added.Blank tests show that: under the production condation at room temperature, silica conversion rate in straw were not be very high, it remained at 3 percent in general. The conversions of various straws were not very different to each other. However, at higher temperature, the silicon conversion of straw will impact the final active silicon outcome prodigiously. So, the active silicon from straw should be taken into account in evaluation of the actual producing process.In the fertilizer production process, both solid wastes, fly ash, or coal gangue were reacted with crop residues respectively. A series of orthogonal test show that: in the fly-ash- silicon fertilizer testing, the experiment process occur a greater influence on the conversion of silicon in ash or gangue, and best result was obtained with the fly ash, KOH, straw and H₂O₂ were added simultaneously; and at this moment, fly ash reacted with straw at once under the existent of KOH and was transferred into active silicon. From testing data, H₂O₂ must play a facilitating role in the conversion of silicon, but its accession time should be further studied. The reaction time affects the conversion rate of silicon, too.In the gangue fertilizer experiment, the process of fertilizer greatest affected the rate of silicon conversion in coal gangue, and the pre-hydrolysis in the first experiment is helpful for heightening the silicon content in fertilizer. Reaction time is also affect the silicon conversion in gangue at some extent, the highest conversion of silicon from coal gangue was obtained at the longest time; But the law of time affecting on silicon conversion was not found now. The gangue size is also affect the silicon conversion, and the smallest size of gangue responses to the best effect.In the experiments at high temperature, silicon conversion is increasing ceaselessly with the temperature rising.