On the Efficiency of Soil Crushing Plant for Soil Dressing by Hydraulic Power

Abstract

Large-scale soil dressing by hydraulic power requires various soil crushing devices not only to crush soil by water jet, but to disperse, sort, and crush soil in mud water so that mud may be smoothly transported to remote places.Precise knowledge of their performances is thus considered as important as their installation itself.
In the present work, the performance of the soil crushing plant in Akasobu area of the Tonami (Toyama Prefecture) soil dressing project with mud water, the largest project of its kind in this country, was closely watched for the period of three years;the results were examined on the basis of newly defined effective pass percentage of grain size (C_n) and difference in effective pass percentage of grain size (f_n, f'_n).
Using cn, the concentration of mud (m) and the grain size distribution can now be uniquely correlated; the relationship between the input and output flows is obtained unambiguously from comparison of the corresponding m-c_n plots.The use of f_n and f'_n enables one to quantitatively assess the performance of each soil crushing device.
The results obtained indicate that the soil crushing performance depends greatly on the mud concentration; data relating to the performance and mud concentration necessary for designing various soil crushing devices have thus been obtained.