A process for the harmful substance immobilization by temporally and / or spatially controlled crystallization and precipitation of barium sulfate

摘要

This invention concerns a process for immobilizing hazardous material by temporally and/or spatially controlled crystallization and precipitation of barium sulfate (BaSO4) in porous and/or fissured stones and/or stone debris, the external and internal surfaces of which containing hazardous material are contacted with a super-saturated solution of a practically insoluble material. After suppression of the super-saturation, the practically insoluble material of the solution precipitates and covers the external and internal surface containing the hazardous material, which renders impossible the mobilization of the hazardous material via chemically and biologically or by dissolving. The aim of the invention is to develop a simple and comprehensive process for immobilizing hazardous materials, particularly heavy metals, in porous and/or fissured stones and/or stone debris and thereby to permanently avoid damage to ecosystems from mobilization of the hazardous materials. This aim is achieved by the invention in that a solution of a temporarily acting inhibitor and components of a material of low solubility flow through the porous and/or fissured stones and/or stone debris, whereupon the material of low solubility precipitates because the effect of the inhibitor is cancelled out. The low-solubility material used in the invention is BaSO4.