粒状土壤改良剂制备及其崩解性能研究

发布时间：2018-06-01 13:23

本文选题：土壤改良剂 + 造粒　；参考：《西安建筑科技大学》2017年硕士论文

【摘要】：土壤是人类赖以生存的基础,近年来出现了许多土壤问题,严重地制约了农业的可持续发展。土壤改良剂常用来调理障碍土壤,但粉状改良剂在实际的使用过程中存在不少问题,如难以实现均匀地抛洒,易产生扬尘危害,并且不能根据实际情况快速地按照比例进行调配。因此,解决粉状改良剂在实际使用中的问题,对改良剂的推广具有重大的意义。本次课题采用圆盘造粒机对粉状改良剂进行造粒研究,并通过崩解仪对影响粒状改良剂崩解的相关因素进行探讨,目的是制备具有一定强度的粒状土壤改良剂,并且粒状土壤改良剂能够快速遇水发生崩解,进而对障碍土壤进行改良,主要的研究结论如下:1、磷矿粉经研磨处理,特征粒径减小,比表面积增大,颗粒间发生团聚现象。随着研磨时间的延长,磷矿粉有效磷含量增加,氟磷灰石、石英、羟基磷灰石三类主要矿物相特征峰衍射强度均不同程度减弱,结晶程度降低。2、成粒率与合格率随着圆盘转速的增大而增大,两者随着圆盘倾角和加水量的增加,先增加后减小。当转速为35r/min,倾角为60°,加水量为35%时,造粒效果最好,成粒率、合格率分别为83.34%、69.59%;磷矿粉、白云石造粒效果优于沸石和有机肥;磷矿粉细度越小,成粒率越大,沸石含量越多,成粒率越低;成粒率随凹凸棒土添加量的增加而增大,膨润土添加量对造粒结果没有影响;当凹凸棒土、淀粉、聚乙烯醇添加量均为10%时,相比较凹凸棒土,淀粉与聚乙烯醇的造粒效果更好,且具有显著性差异,成粒率分别增加了10.40%、21.05%。3、磷矿粉细度越小,崩解时间越长。同一研磨时间下不同配比崩解时间排序大致为1:15组1:30组1:0组;不同颗粒大小崩解时间排序为5~10mm组3~5mm组1~3mm组;崩解时间随膨润土添加量的增加而减小,凹凸棒土添加量对崩解特性没有影响;当膨润土、微晶纤维素、羧甲基淀粉钠添加量均为5%时,崩解时间排序为微晶纤维素羧甲基淀粉钠膨润土,三者差异显著。4、不同崩解剂的吸水速度大小排序为膨润土羧甲基淀粉钠微晶纤维素,饱和吸水量排序为羧甲基淀粉钠微晶纤维素膨润土,微晶纤维素与膨润土差别不大,仅为1.75%;三种崩解剂吸水过程均符合吸水动力学方程,吸水滞后时间排序为羧甲基淀粉钠微晶纤维素膨润土,相比较羧甲基淀粉钠,膨润土和微晶纤维素吸水滞后时间分别减少了43.00%、12.33%。吸水速率常数方面,相比较微晶纤维素,膨润土和羧甲基淀粉钠吸水速率常数分别增加了37.20%、4.71%。综上可知膨润土亲水性最好,且吸水速度最快,崩解效果最好。5、干燥试验结果表明,由于升速阶段和恒速阶段时间都比较短或者不存在,所以本部分重点研究降速干燥阶段。选取的四大因素中,干燥温度对湿分比和干燥速度的影响最为显著,其次是加水量,磷矿粉细度和凹凸棒土添加量影响不大。总体而言,随着干燥的不断进行,干燥速度逐渐降低,且到后期各因素对其影响变小。干燥温度对湿分比的影响可以通过Wang经验模型进行模拟,拟合效果较好。
[Abstract]:Soil is the basis of human survival. In recent years, many soil problems have appeared, which seriously restrict the sustainable development of agriculture. Soil amelioration is often used to regulate the obstacle soil, but there are many problems in the practical use of the modifier, such as it is difficult to achieve uniform spraying, easily produce dust hazards, and can not be based on actual conditions. Therefore, it is of great significance to solve the problems in the actual use of powdery improver in practical use, and it is of great significance to popularize the improver. This subject uses a disc granulation machine to study the granulation of powdery improver, and discusses the related factors affecting the disintegration of granular modifier through disintegration instrument. The preparation of granular soil modifier with a certain strength, and the granular soil improver can disintegrate quickly with water, and then improve the barrier soil. The main research conclusions are as follows: 1, the phosphate rock powder is grinded, the characteristic particle size decreases, the specific surface area increases, and the particle agglomeration occurs between the grains. With the prolongation of the grinding time, the phosphate rock powder is extended. With the increase of effective phosphorus content, the diffraction intensity of the characteristics peak of three major mineral phases of fluorapatite, quartz and hydroxyapatite decreased in varying degrees, and the degree of crystallization decreased by.2. The grain percentage and qualified rate increased with the increase of disc speed. Both increased and then decreased with the increase of disc angle and water increase. When the rotational speed was 35r/min, the dip angle was 60 degrees. When the amount of water is 35%, the granulation effect is best, the percentage of granulation is 83.34%, and the qualified rate is 83.34%, 69.59%. The granulation effect of phosphorite powder and dolomite is superior to that of zeolite and organic fertilizer; the smaller the size of the phosphate ore, the greater the grain yield, the more the zeolite content, the lower the percentage of the granulation, and the increase of the grain percentage with the increase of the amount of attapulgite soil, and the amount of bentonite added to the granulation result. When the amount of palygorskite, starch and polyvinyl alcohol is 10%, the granulation effect of palygorskite is better than that of palygorskite, and the granulation effect of starch and polyvinyl alcohol is better, and there is a significant difference. The grain percentage increase by 10.40%, 21.05%.3, the smaller the fineness of the phosphate rock, the longer the disintegration time. The sort of disintegration time of different proportions is roughly 1 under the same grinding time. 15 groups of 1:0 group at 1:30 group, the disintegration time of different particle size is 5~10mm group 3~5mm 1~3mm group, and the disintegration time decreases with the increase of bentonite addition, and the amount of attapulgite soil addition does not affect the disintegration property. When bentonite, microcrystalline cellulose and sodium carboxymethyl starch are added to the amount of sodium carboxymethyl starch, the disintegration time is ordered to be microcrystalline cellulose Suo Jiaji The difference between the three kinds of sodium starch bentonite is.4, the water absorption rate of different disintegrating agents is bentonite Carboxymethyl Starch Sodium Microcrystalline Cellulose, the saturated water absorption is sorted by Carboxymethyl Starch Sodium Microcrystalline Cellulose bentonite, and the difference between microcrystalline cellulose and bentonite is little, only 1.75%. The water absorption process of the three disintegrating agents all conforms to the water absorption kinetics. The water absorption lag time was sorted by Carboxymethyl Starch Sodium Microcrystalline Cellulose bentonite, compared with sodium carboxymethyl starch, the water absorption lag time of bentonite and microcrystalline cellulose decreased by 43% respectively, and the water absorption rate constant of 12.33%. was compared with microcrystalline cellulose, and the water absorption rate constant of bentonite and carboxymethyl starch sodium increased by 37.20%, respectively. It is found that the hydrophilic property of bentonite is the best, and the water absorption speed is the fastest and the disintegration effect is best.5. The drying test results show that, because of the short or non existence of the speed and the constant speed, this part focuses on the study of the effect of drying temperature on the wet fraction ratio and the drying speed of the four major factors. The most significant, the next is the amount of water, the fineness of phosphate rock and the amount of attapulgite have little effect. As a whole, the drying speed gradually decreases with the continuous drying, and the influence of various factors on it is smaller in the later period. The effect of the drying temperature on the wet fraction can be simulated by the Wang empirical model, and the fitting effect is better.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S156.2

【参考文献】