PROSPECTS FOR THE USE OF EXCESS ACTIVATED SLUDGE FOR THE RECLAMATION OF SPENT QUARRIES

Abstract

Kemerovo region – Kuzbass occupies a leading place in Russia in the accumulation of non-recycled waste. At the same time, being a leader in open-pit mining, the region is in dire need of effective reclamation of disturbed areas. The use of large-tonnage secondary material resources as a recultivant will contribute to solving two acute environmental problems at once.

The construction and launch of its own sewage treatment plants by Kuzbass, the largest waste paper processor in the Kemerovo Region, will lead to the formation of a multi–tonnage waste – excess activated sludge generated at the stage of biological wastewater treatment. Therefore, already at the stage of construction and start-up of sewage treatment plants, it is necessary to develop an effective technology for the disposal of this type of waste.

The article presents an analysis of information sources on the problem of disposal of excess activated sludge, ways to bring it to standard indicators and the possibility of using it as a secondary material resource for the reclamation of disturbed lands.

The purpose of our research was to find the best available technology for Kuzbass Scarab LLC for the disposal of excess activated sludge from wastewater treatment plants by using it for the technical stage of reclamation of spent quarries. The object of the study, the results of which are presented in this article, was IAI from the sewage treatment plants of the CBP enterprise (an analog facility) as part of substrates with inert materials (excavation soil (clay) and construction debris (scrap bricks and concrete)). The selection of the optimal composition of substrates based on IAI and inert materials for the technical stage of reclamation of disturbed lands was the subject of research. The result of the analysis of scientific publications and regulatory documents was the selected component composition of substrates based on IAI for the technical stage of land reclamation disturbed by mining.

Laboratory studies of samples of excess activated sludge from the sewage treatment plants of the CBP enterprise (analog facilities) have shown that the sample taken from sludge maps (mass fraction of dry matter 44%, pH of salt extract 5.8) according to these indicators meets the regulatory indicators established for such materials when used at the technical stage of reclamation, and the IAI sample after decanter centrifuge (mass fraction of dry matter 14%, pH of salt extract 6.8) – may be suitable for the intended purpose only after additional treatment.