The article deals with the problem of disposal of the sludge formed after the treatment of wastewater at the production of chemical fibers. Sludge after sedimentation is stored in storages and pollutes the environment. We carried out a comparative analysis of existing methods of disposal of sewage sludge from chemical production, which showed that the most environmentally friendly way is pyrolysis. We have analyzed the chemical and fractional composition of ash sludge after pyrolysis. The analysis revealed that the resulting ash waste is similar to ash from coal-fired power plants, which makes it possible to use it as a microfill for paving roads or sidewalks. By selling the ash waste it is possible to reduce the payback period of the pyrolysis unit installation and reduce the ecological load on the environment.

Keywords: pyrolysis, sludge, sediment, ash, disposal

One of the most massive polymer waste of consumption is car tires that are going out of service. The disposal of such tires at a solid waste landfill is an extremely inefficient way of their disposal, entailing an increase in the area of landfills and an increase in negative environmental impact. The least financially and labor-intensive way of processing automobile tires is grinding into fractional crumbs. To reduce the costs of sorting and further grinding of tires, a shredder with a dispersion of 3 mm is used. The article suggests the use of rubber crumbs as a binder when laying highways. Studies of indicators affecting the operational parameters of asphalt pavement at different values of the mass of rubber crumbs in comparison with a clean sample were carried out and the optimal specific mass of the added crumbs was determined, which was 15-20%.

Keywords: rubber crumb, tires, asphalt mix, optimal weight

The article considers the possibilities of using a large fraction of coal industry enrichment waste in road construction. The use of waste rock as a large aggregate in the composition of road concrete is proposed, because the enrichment waste is not disposed of properly, but is sent to the tailings dump. These dumps occupy large areas of land, thereby causing damage to the environment. The fractional composition of coal waste from the enrichment of the Gukovo-Zverevsky coal-bearing area is analyzed. From the results of sieving, it was seen that the structural composition satisfies the size of the fractions of a large aggregate for the concrete mixture. Analytical studies of the composition of the concrete coating were carried out. Based on the analysis of the composition of the concrete mixture, we came to the conclusion that tailings waste can be used as a major substitute. A comparative characteristic of the requirements put forward for the resulting mixture is presented. In our work, one of the main qualities of the road concrete pavement was tested - strength. The results of experimental strength tests of control samples of concrete with various types of aggregate are presented. Based on the results obtained, it is possible to draw a positive conclusion about the possibility of using enrichment waste as a large aggregate of concrete mixture in road construction according to technical and economic criteria.

Keywords: road construction, concrete mix, enrichment waste, coal rock

The increasing problem of the formation of ash dumps in the Rostov region dictates the need to search for environmentally friendly methods of waste disposal in the heat and power sector. In this article, the ash and slag waste of the Novocherkassk GRES is considered. We analyzed the chemical and fractional compositions of the ash-slag mixture formed at a coal-fired thermal power plant and proposed the use of ash waste with a size of 10-100 microns in road construction as a micro-filler. To study the strength of the road surface using ash microparticles, we manufactured and tested cubes of modified concrete mixture for compression using a press machine. The obtained result showed that the use of ash as a micro-filler in concrete does not affect its strength in any way. The tests of control samples with the use of ash wastes showed an improvement in the water resistance and frost resistance of concrete while maintaining its strength.

Keywords: ash and slag waste, micro-filler, concrete mix, road construction