Municipal Solid Wastes-to-Energy Conversion: Global and Domestic Experience (Review)

Abstract

Data are presented on the dynamics of development and current state of the municipal solid wastes (MSWs)-to-energy conversion in Europe, the United States, Japan, and China and on the prospects for its implementation in Russia. The European and domestic approaches to the definition of the term “energy recovery” are examined. Note that the mandatory requirement of the Russian legislation for the preparation of wastes before incineration (there is no such criterion abroad) can be a serious obstacle to the development of the MSWs-to-energy recovery industry in Russia. According to the global experience, the facilities engaged in energy recovery from MSWs are, in fact, thermal power plants (TPPs) fired basically with solid municipal wastes (TPPs operating on MSWs). The factors affecting the energy efficiency of such TPPs are determined. It is noted that the grate combustion of MSWs, as compared to other technologies, offers maximum energy efficiency with a comparable environmental impact. The connection of an MSW-fired TPP to a continuous consumer of heat, such as a municipal heat-supply system, has been demonstrated to considerably increase its energy efficiency. Examples are presented of such TPPs operating under cogeneration conditions. It is noted that, for modern MSW-fired TPPs, the semidry treatment of flue gas is the best solution as to the attainment of the required harmful emission level and the energy efficiency of the overall TPP. The options are examined for increasing the electrical efficiency by raising the superheated steam pressure and temperature, reducing the steam temperature (or pressure) at the turbine outlet, and cutting down heat losses in the boiler. It is noted that the advisability of introducing measures to improve the energy efficiency of MSW-fired TPPs should be determined on a case-by-case basis using the results of a feasibility study as applicable and considering local conditions. It is critical that these measures would not prevent the safe and efficient disposal of the wastes at these TPPs. A description is presented of four MSW-fired TPPs being constructed in the Moscow oblast that are designed for energy recovery from approximately 2.8 million t of wastes per year.