ABSTRACT

The use of thermochemical methods for the disposal of sewage sludge is becoming the main way to prevent environmental harm. This chapter discusses the main reasons why thermochemical methods become the optimal solution: the content of heavy metals in sewage sludge and the associated alkylation processes, the presence of pathogenic and specific microflora and the content of persistent organic pollutants. The basic technological schemes of combustion, pyrolysis and gasification of sewage sludge are considered separately. Comparative characteristics of technologies and devices (furnaces) for heat treatment of waste are discussed. The prospects of using the products of thermochemical treatment of sewage sludge for the commercialization of ash from the combustion of sewage sludge and the production of value-added products are considered. Ash and slag wastes contain a large amount of silicates; a similar elemental composition is available in the materials of the silicate industry, which means that there is a possibility of using ash in the production of glass materials. It becomes possible to use a new type of glass materials as thermal insulation materials. It is shown that the incineration of sewage sludge along with the incineration of a hard-to-recycle fraction of municipal solid waste can be organized into a closed-loop chain.