Development of energy-efficient technical solutions for modernization of rotating furnaces of electrode production with partial replacement of natural gas with syngas
The gasification method with the highest value of the syngas calorific value and the prototype of equipment for calcining carbon-containing bulk material are substantiated. A mathematical model of the process of gasification of bulk carbon containing material in a drum-cooler of a rotary kiln was developed, based on a continuous-discrete formulation of the interaction of a mixture of reacting gases with a discrete solid phase, taking into account the turbulent flow regime and thermal radiation. The formulated mathematical model includes thirteen global reactions, of which four are heterogeneous and nine are homogeneous. A mathematical model has been developed for the combustion of synthesis gas together with natural gas in the working space of a rotary calcining furnace in a continuous formulation, which is necessary to determine the energy efficiency of the gasification process. Using the developed mathematical models, the regularities of the processes of gasification in a drum-cooler and combustion of synthesis gas together with natural gas in the working space of a rotary kiln were obtained. Technical solutions have been developed for the heat treatment of the carbon-containing filler of the electrode industry in rotary kilns with partial replacement of natural gas with synthesis gas and recommendations for modifying the designs of thermal equipment and technological regulations for its operation. The developed technical solutions include draft designs of a rotary kiln gasifier-cooler, which is a modernized operating equipment for a calcined material cooler drum, and a water-cooled burner for burning synthesis gas together with natural gas without preliminary mixing in a rotary kiln. On an industrial rotary kiln for calcining bulk carbon-containing materials (anthracite, petroleum or shale coke), experimental data were obtained, confirming the effectiveness of the developed technical solutions.