The Active Mechanism Of Phosphate Microstallization And Its Application For Anaerobic Digestion And Soil Phosphorus Supplement

Three typical phosphorus minerals were selected as research materials to be crystallized,and then the physical and chemical properties and phosphorus release characteristics of microcrystalline mineral material were analyzed by using advanced detection method.The change of production of biogas,biogas composition in the anaerobic fermentation as well as the content of VFA,COD,p H,and nutrients N,P,K in the biogas slurry with microcrystallized phosphate or potassium mineral powder as a catalyst was studied.The role of microcrystalline mineral powder in the growth of different crops,nutrient uptake and amendment of soil physical and chemical properties was also verified in the study.(1)The variation of particle size,specific surface area,surface morphology,and lattice structure of microcrystallized phosphate mineral powder in the machining process was dissected through the evaluation of microcrystalline physical and chemical properties,which demonstrated the role of mechano-chemical effect in terms of physical activation.Three typical phosphate rocks were processed into highly active microcrystalline phosphate powder as water insoluble phosphate fertilizer by mechanochemical force of high energy.The study realized the optimization of crystallization process and analyzed the effect of microcrystallization of different milling times on mineral compositions and crystal structure of three phosphate powders by X-ray diffraction method.It showed that the main mineral compositions of the Yunnan phosphate powder was Ca₅(PO₄)₃F and Si O₂,that of Hubei phosphates powder was Ca₅(PO₄)₃F and Ca CO₃,and that of Henan phosphates powder was Ca₅(PO₄)₃F,Si O₂ and Fe₂O₃.The profiles of X-diffraction peak of the main minerals of three phosphate rocks were changed by the microcrystallization.The heights of X-diffraction peak gradually decreased.The internal lattices distort.The crystallization degree decreased,disordered and amorphous degree increased.The abrasive amorphous contents increased.The changes of phosphates rock were significantly different.With the processing time prolonged,mechanical activation degree of phosphate powders were increased.The impact of lignite as an activator on Hubei phosphate powder by microcrystalline process was studied.The results showed that with the increase of milling time,the diameter(D₅₀,D₉₇)demonstrated the overall downward trend,while the specific surface area showed a rising trend,both of which were negatively correlated.With the increasing amount of added activator,ultrafine particles(d?1.0?m)and fine particles(d?10?m)firstly increased and subsequently decreased after 25 min when ultrafine particles and fine particles accounted for 48.31%and 92.66%,respectively with addition of 2%activator.(2)The synergistic role of activator and mechanical force chemistry in the process of crystallization in improving release amount and rate of available phosphorus was confirmed by biological effects analysis.The catalytic activity of phosphorus and potassium mineral powder were verified by anaerobic fermentation,which increased bioavailability.The phosphorus release and its release effect in weakly acidic environment were studied.The results showed that with the extension of milling time,the dynamic change of available phosphorus content of Hubei and Henan phosphate powder showed the overall upward trend,while Yunnan phosphate powder showed the overall decreasing trend.The amount of available phosphorus in Henan powder was greater than Hubei and Yunnan.In order to improve the efficiency of biogas fermentation and biogas yields,the phosphorus and potassium powder as the functional catalysts of biogas fermentation,as well as to explore its influence on anaerobic fermentation of cow dung.Eight treatments were contained as follows:no addition(CK),the addition of Yunnan microcrystalline phosphate powder of 2.5%(T1),5.0%(T2),7.5%(T3),10.0%(T4),as well as Henan microcrystallization phosphate powder 5.0%(T5),Yunnan common phosphate powder5.0%(T6),and Henan microcrystalline muscovite powder 5.0%(T7).With the increase of microcrystalline phosphate powder concentration,the ultimate production of biogas was improved significantly.Adding 7.5%microcrystalline phosphate powder treatment started the fastest,produced gas most efficiently,CH₄ volume fraction was up to 62.5%,the removal rate of whose VS reached 61.99%,and at the same time it effectively removed of COD in biogas slurry,reduced the content of VFA respectively.However,the ultimate production of biogas was inhibited by 317.63 m L/g·VS when microcrystalline phosphate powder concentration was as high as 10.0%.Adding microcrystalline phosphate powder 7.5%was the appropriate additive amount to improve the anaerobic digestion of cow manure.This study provided a theoretical basis for developing a highly efficient biogas catalysts formula.(3)The role of the microcrystalline mineral in the growth of crop and soil ecological transformation was verified by agronomy effect analysis.The application of microcrystalline phosphate mineral activated by different activators(lignite,bentonite,zeolite,phosphate-solubilizing bacteria,citric acid,furfuralresidue)was studied with potted carrots as materials.The results showed that application of various activated microcrystalline phosphate powders,to varying degrees,improved the absorption and utilization of phosphorus,promoted the growth and improved the yield and plant biomass yield of carrots.The activation of phosphate solubilizing bacteria powder worked best.With potted red amaranths as research materials,the effects of high ash potassium,mica and ceramics of mica,feldspar and feldspar powder of ceramics,microcrystalline powder of potassium-rich shale on red amaranth growth,yield and soil available K and slowly available potassium content were studied.The results showed that application of different kiln ash potassium and potassium ore can promote the growth and production of red amaranth.Under the same effective nutrient condition,kiln ash potash had the best yield-increasing effect on red amaranth.Microcrystalline minerals can promote red amaranth yield,but less effective than rapidly available potassium.The kiln ash potash as one of different types of potassi?m ore can significantly improve soil available potassium levels.Except slag,the feldspar,mica,and potassi?m-rich shale can significantly improve slowly available potassium level in soil.Microcrystallization grinding can promote the release amounts of feldspar,mica and other insoluble potassium minerals potassium,and improve the content of acid-soluble potassium.