The purpose of the research is to analyze the possibilities and features of using the laser diffraction method for studying the particle-size distribution of soils. This method is relatively new and has several advantages compared with the classical pipette method, namely: high velocity, accuracy and automation of the analysis, the ability to use trace amounts of the sample, the determination of the particles fractional composition in a wide range of sizes, including using any classification scales. To understand correctly the results obtained by laser diffraction, it is necessary to be convinced that they correspond to the substance nature and reflect accurately the fractional composition of elementary soil particles (ESP) that form the soil solid. The particle-size distribution of ordinary carbonate chernozem, natural river quartz sand, standard samples used to calibrate the analyzer, as well as powders of titanium and zinc oxides was identified on an Analysette 22 NanoTec analyzer. The data obtained with the laser diffraction method are presented in comparison with the pipette method and the results obtained by electron microscopy. Determination of the fractional composition of the daily sample obtained from a sample of chernozem by the Kachinsky method showed that even after applying ultrasonic exposure, the amount of silt particles does not exceed 15.2 %, whereas by using the pipette method, the content of particles less than 0.001 mm is 36.84 %. Thus, the results of the assessment of the fractional composition of the ESP obtained by laser diffraction and the pipette method have significant differences. At the same time, a high convergence of the data obtained using the methods of laser diffraction and electron microscopy was found.
Keywords: laser diffraction analyses, particle-size distribution, sedimentation, pipette method, chernozem, elementary soil particles.
DOI: 10.31774/2222-1816-2019-1-184-194
V. E. Boldyreva, O. S. Bezuglova, I. V. Morozov ON THE QUESTION ON DETERMINATION OF PARTICLE-SIZE DISTRIBUTION OF SOIL USING THE LA-SER DIFFRACTION METHOD Scientific Journal of Russian Scientific Research Institute of Land Improvement Problems. 2019. No 1. P. 184-194 DOI: 10.31774/2222-1816-2019-1-184-194
