ABSTRACT
The article deals with an innovative light technogenic soil obtained by utilization of sulfur-alkali desulfurization waste. The environmental safety of the lightweight technogenic soil has been proved. The granulometric composition of the product, its density, moisture and compaction ability in comparison with natural soils have been studied. Based on the determination of physical and mechanical characteristics, the conclusion about the possible use of the obtained material as a technogenic soil was made. The most important advantage of the product is its density, which is on average 30% lower than the density of natural disperse soils. Also noteworthy is the increased strength properties of the lightweight soil established in laboratory tests.
Sulfur-alkali wastes are formed during cleaning of pyrolytic gases from hydrogen sulfide and carbon dioxide with sodium hydroxide solution. The effluents are formed in a number of processes: during the purification of liquefied gases, the production of lower olefins, the purification of kerosene and gasoline fractions and some other petrochemical processes. The resulting sulfur-alkali wastes are aqueous solutions of usually yellow-brown color with a pungent bad smell and alkaline reaction of the medium. From the chemical point of view, sulfur-alkali waste contains, in addition to sodium sulfide, a complex mixture of polysulfide, mercaptide and carbonate sodium salts, sodium phenolates, as well as mechanical impurities and various oil products in the dissolved or colloidal form.
Thus, sulfur-alkali wastes pose a dual environmental hazard: they contain toxic sulfur (II) compounds, mainly of the sulfur-organic type, and have a high pH due to the high content of sodium hydroxide in the solution
