Purpose. To reduce natural gas consumption in the technological process of high-temperature processing of coal-containing bulk materials in rotary kilns.
Specifications. Experimental testing of the developed technical solutions for the production and use of synthesis gas on modernized industrial equipment showed: – at a ratio of O2/C = (40–53)% in the developed gasifier-cooler of a rotary kiln, the quantitative composition of combustible gases of synthetic gas in molar fractions is: CO = (32-38)%, H2 = (17-19)%; – direct generation of synthesis gas and its combustion in a rotating calcination furnace by supplying water vapor into its working space allows saving up to 40% of natural gas consumption in maintaining the desired temperature level of the process of calcination of carbon-containing raw materials in the furnace.
Application area. Electrode and metallurgical industry.
Advantages. Compared with existing technologies for producing synthetic gas, the new technology for partial or complete replacement of natural gas with syngas in rotary calcining furnaces of the electrode industry has the following advantages: – for the production and combustion of synthetic gas, existing modernized equipment is used, rather than expensive specialized equipment used in existing technologies; – due to partial or complete replacement of natural gas with synthetic gas, it is possible to reduce the consumption of natural gas by (10.5–26.3) nm3 per ton of product; – partial replacement of natural gas with synthesis gas reduces the cost of carbon-containing material – a filler for carbon-graphite products, the main consumer of which is the ferrous metallurgy.
Technical and economic effect. The factors for creating an economic effect from the introduction of technology are: first – generation of synthetic gas with productivity in the cooling drum of a rotary kiln and its combustion in the working space of the rotary kiln with partial or complete replacement of natural gas; the second is the direct generation of synthesis gas and its combustion in a rotating calcination furnace by supplying water vapor into its working space, which allows saving up to 40% of natural gas consumption in maintaining the required temperature level for the process of calcination of carbon-containing raw materials in the furnace. The economic effect of introducing developments into industry is to reduce natural gas consumption (10.5–26.3) nm3 per ton of product.
Description. Technical solutions have been developed for the heat treatment of carbon-containing filler in the electrode industry in rotary kilns with partial or complete 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 preliminary designs of a gasifier-cooler for a rotary kiln, which is a modernized existing equipment of a cooling drum, a water-cooled burner device for burning synthesis gas together with natural gas without pre-mixing, and a device for supplying atmospheric air to the calcination zone. On an industrial rotary kiln for calcination of bulk coal-containing materials (anthracite, petroleum or shale coke), experimental research data were obtained confirming the energy efficiency of the developed technical solutions.