Application of Demolition Products of Buildings and Structures to Ensure Reduction of Concentration of Heavy Metal Ions in Man-Made Soils at Construction Facilities

Abstract

The article considers the problem of soil contamination in St. Petersburg with heavy metals. It has been shown that the degree of contamination is such that soils lose their ability to self-clean and can be attributed to technologically modified soils. Geochemical barriers are required to reduce the concentration of heavy metals. Based on the principle of A.I. Perelman, it is shown that the most promising wastes of the construction industry for use in geochemical barriers are silicate-containing wastes from demolition of buildings and structures. Capacity of heavy concrete and aerated concrete in relation to some heavy metals is determined in the work. The absence of selectivity of wastes to various heavy metals is shown. The formula for calculation of the life of the geochemical barrier taking into account its size, capacity and amount of contamination coming with melted and rain drains is proposed. The life of the geochemical barrier is calculated to prevent the migration of iron ions in the form of a railway embankment, which amounted to 47 years, provided that granite crushed stone is completely replaced by heavy concrete.