Conversion of limestone-limestone mining waste by impregnation with polysulfide solutions

Abstract

The data of studies on the effectiveness of impregnating Aquastat waste generated as a result of the development of limestone-shell rock deposits are presented. As a result of sand impregnation, the water absorption coefficient as a result underwent a significant decrease from 7 to 17 times, while the water absorption coefficient decreases from 32.5% for the initial to 1.9% impregnated. Even treatment with low concentrated (ρ = 1.17 g / cm 3) calcium polysulfide solution made the water absorption coefficient to decrease to a value of 4.5%. As a result of impregnation of crushed stone from limestone-limestone with a solution of calcium polysulfide, the water absorption coefficient decreases from 25.0% for untreated to 5.2% for treated, and the decrease in the coefficient of water absorption is greater for concentrated solutions. It was found that a solution density of 1.24 g/cm 3 is sufficient to reduce the water absorption coefficient to a value of 5.2%, the same as for a density value of 1.35 g/cm 3. Comparison of the results of impregnation with «Aquastat» solution and sulfur melt showed that as a result of treatment with sulfur melt, the water absorption coefficient decreases by 13.3 and strength increases by 2 times, and as a result of impregnation with «Aquastat» solution decreases by 4.62%, strength increases by 1.35 times. Despite the high efficiency of sulfur melt processing, such treatment has drawbacks associated with the use of autoclave technology and high temperatures. The results of the modification of sand and crushed stone from shell rock by impregnating it with the «Aquastat» solution, a significant decrease in the water absorption parameter, an increase in compressive strength, revealed the possibility of using impregnated crushed stone as the layer material lying at the base of the road structures of local roads in the form of crushed stone and sand instead of the more expensive imported crushed stone.

Biological activity of sulfur nanoparticles in the sulfur-dimethyl sulfoxide-water system

“…Thus, we propose a new and easy method for obtaining stable colloidal solutions of sulfur. The nanosulfur in a system with water can be used for antifungal and antimicrobial treatment of cultivated plants [ [13][14][15][19][20][21][35][36][37][38][39], and can make it possible to use nanosulfur in this system for hydrophobization of porous materials [16,19,21,55,56].…”

Influence of Dynamics of Changes in the Physical Properties of Osteoconductive Granulated Biopolymers on Scafold Stability in the Postoperative Period

“…Limestone is an organic (biogenic) sedimentary rock with calcite and calcite fossils [41]. Besides, an inorganic limestone component, i.e., calcium carbonate, can slowly dissolve in water into carbon dioxide and the corresponding basic oxide [42]. If we analyze basic limestone physical properties, we see that shell limestone density is about 800 kg/m3, tensile strength is about 0,4 MPa, water absorption capacity ranges from 0,1% to 2,1%, and porosity ranges from 0,5% to 35%.…”