Thermolysis waste processing in hydrolysis production

One of the urgent tasks of rational environmental management concerns the recycling of large-tonnages of industrial waste. Occupying significant landfill areas, accumulated waste acts as a source of environ-mental pollution, resulting in a decline in human living conditions. The great quantity of some carbon-containing wastes leads to their consideration as secondary technogenic raw material resources. In particular, since comprising an integral part of the structure of wood and accumulating in large quantities in the wastes of paper pulp and hydrolysis plants, lignin potentially forms a promising basis for producing a wide range of products, including aromatic aldehydes, alcohols, mineral fertilisers and feed additives. However, due to its high resistance to microbiological decomposition and propensity to spontaneous combustion (in dry form), the utilisation of lignin for such purposes presents certain difficulties. Additional limitations affecting existing technologies for lignin processing include the inability to efficiently process large volumes, as well as the remoteness of processing enterprises from storage sites. In the present article, the decomposition of lignin in a microwave thermolysis pilot plant comprising part of an existing waste recycling plant (Tombov, Russia) is investigated in connection with its disposal and extraction of target products. Under the applied microwave radiation, the decomposition time of lignin is reduced in comparison with the traditional method. This is combined with a decrease in volume of utilised substance complemented by its neutralisation and cleaning of pathogenic microorganisms. Based on the results of the study, the technological parameters of the process are determined and the average estimated yield of thermolysis products is provided. The resulting carbon residue can be ap-plied in the production of catalysts and carbon sorbents, while the liquid component can be used as a raw material for low-combustible fuel fractions. The existing gas cleaning system makes the process more environmentally friendly.

hydrolysis production, lignin processing, pilot plant, thermolysis, environmental safety, target products