Том 59, № 3 (2016)

The variation in the maximum fluidity F_max is determined by the Gieseler method for multicomponent blends, as a function of their composition and the fluidity of the individual components. The fluidity F_max may be predicted on the basis of a theoretical curve plotted by analogy with the known curves for blends whose components have similar F_max values.

Ash basicity of coal concentrates and factory furnace charges is defined for the long period of time. Four groups of the coal concentrates that are discriminated by value and stability of ash basicity are identified. The basicity of furnace charges is shown to be sometimes nonadditive relative to basicities of components. This should be taken into consideration when basicity of components is used for corrections of composition of furnace charges.

The paper describes modern requirements on the quality of carbonaceous materials used in the direct iron reduction process. Complex investigations of the quality of brown coals of Kazakhstan with regard to the direct iron reduction process included study of the material composition of the general and mineral parts, petrographic composition, and physicochemical characteristics (density, porosity, CO₂ reactivity, structural strength, and heat resistance). Recommendations and ranking of the studied coals for use as carbon reducing agents are provided.

The industrial introduction of ammonia removal from coke-oven gas by the circulatory phosphate method at byproduct shop 2 in coke production at PAO Severstal’ is considered. The ammonia removed undergoes thermal decomposition. The system consists of three channels (including a backup) and is designed to process coke-oven gas at a rate of 170000 m³/h. The phosphate method is selected after comparing methods of ammonia removal. The startup and operation of the system are analyzed. Operating conditions corresponding to specified ammonia removal are selected. Data are presented regarding the ammonia absorption, the regeneration of the absorbing solution, the thermal decomposition of the steam–ammonia mixture, and the utilization of the smokestack gas from the combustion of the steam–ammonia mixture. With a design productivity of 85000 m³/h for a single channel, the system operates satisfactorily when the throughput of coke-oven gas is in the range 60000–130000 m³/h per channel.

On the basis of the newest metrology concepts formed around the term “uncertainty” and introduced by RMG 29 and GOST P 54500.3 standards, it is the first time when metrological models used in GOST 10742, GOST 27379 and ISO 13909—all devoted to coal sampling, are studied from uniform positions. Ways for effective income quality control and claims management regarding modern mechanical samplers are considered.

The prospects for biotechnology in wastewater processing at coke plants are considered, in conditions of nitrification and denitrification. Wastewater-processing systems employed at Russian and foreign coke plants are compared. The degree of purification is about the same in Russia and elsewhere. However, the treated water does not meet Russian standards for delivery to municipal treatment plants and reservoirs from which fish are taken to be cooked. The single-phase AO VUKhIN biotechnology permits the removal of 80–90% of the nitrate present without the addition of organic reagents, in contrast to classical nitrification and denitrification technology.