Municipal Solid Waste Incineration Furnaces (Review)

The basic data on the global volumes and composition of red mud, which is a highly alkaline waste of the aluminum industry, namely the Bayer process – technology for the extraction and purification of alumina (aluminum oxide) from bauxite are presented. The analysis of the current state of red mud management allows to distinguish the following main directions: physical-mechanical, physical-chemical, biological and combined methods of handling it, which are used in agriculture (chemical land reclamation (increasing soil pH), use as fertilizers); building materials industry (cement, construction mortar, expanded clay, fireclay, bricks, building blocks, ceramic tiles, concrete alkali-acid-resistant products, refractories); road construction (soil strengthening for the lower layers of the road surface, asphalt); production of other materials (sorbents, catalysts, flocculants, pigments, caustic soda, filler for polymer composites); ferrous and non-ferrous metallurgy. Currently, the most common methods of red mud utilization are its direct use, use in the construction materials industry, as well as pyrometallurgical technologies, as a result of which iron or its alloys are obtained, as well as slag, from which alumina, titanium, rare earth metals can be extracted or which is processed into various building materials. The most expedient method of red mud disposal is either direct use of red mud with minimal changes in its properties, or complex processing with maximum yield of target components and minimization of new waste generation. At the same time, one of the promising ways of red mud management can be its biological processing with the help of plants and microbes, which will help reduce the dangerous man-made load from red mud in the territory adjacent to bauxite processing plants. Bibl. 113, Fig. 2.

A State of Art and Prospects of Red Mud Management

Mikulionok

2024

Prospects of the Application of Low-Temperature Pyrolysis Processes for the Thermal Destruction of Hydrocarbon-Containing Waste of Various Origins

Sezonenko,

Aleksyeyenko,

Trotsenko

et al. 2024

A generalized analysis of the existing methods of utilization of hydrocarbon-containing waste of various origins and practical data on the existing experience of using low-temperature pyrolysis processes for the thermal destruction of hydrocarbon-containing municipal and oil waste are presented. A series of studies of thermochemical processes of waste destruction were conducted for both municipal solid waste and industrial waste. The common feature that unites the objects of research is their wide morphology, the presence of the predominant proportion of hydrocarbons and their derivatives. To implement the process of low-temperature pyrolysis of hydrocarbon-containing waste of various origins, a universal installation with a rotating reactor is proposed. The features of its operation, technical characteristics and advantages are presented. The prospects for further development of low-temperature pyrolysis technology for the utilization of unsorted waste groups from sorting complexes are substantiated. Bibl. 30, Fig. 2, Tab. 2.

Conversion of Carbon-Containing Raw Material Using Plasma Technologies

Zhovtyansky,

Dudnyk,

Ostapchuk

et al. 2023

The state of development of plasma gasification technologies of carbon-containing raw materials in Ukraine is analyzed. It is shown that despite some pessimistic domestic assessments of the prospects for their development, the state of research and development in this field at the global level indicates the inevitable breakthrough directions for the development of such technologies and, first of all, in the field of hydrogen energy. In particular, this concerns the prospects of using such difficult-to-process raw materials for hydrogen production as, for example, sewage sludge or worn automobile tires. This will create an additional powerful effect from their implementation, bearing in mind the solution of complex environmental problems of modern Ukraine. The experimental part of this work is devoted to the study of the prospects of such processing, using the example of a laboratory version of a plasma chemical reactor, made according to the scheme of the process of inverted gasification of solid organic raw materials with the introduction of a plasma jet into the pyrolysis zone. The output of hydrogen depended on the raw material: the lowest one was from sewage sludge pellets, and the highest one was from rubber crumb of worn automobile tires; in the case of gasification of a mixture of sewage sludge pellets and rubber crumb, an intermediate value of this indicator was observed. It is important that the output of hydrogen was determined not so much by its content in the raw material, but by the reactivity of the latter, which also corresponded to the degree of use of water vapor. The level of reactivity determined the degree of use of water vapor in the case of pellets up to 29 %, and rubber crumb up to 56 % and, accordingly, the chemical efficiency of gasification reached 39 % and 55 %. It follows from the results of the research that in the conditions of relatively low temperatures in the experimental reactor, the mixing of pellets of sewage sludge and rubber crumb does not create a synergistic effect of advantages regarding the energy efficiency of the process. Bibl. 58, Fig. 4, Tab. 4.