卷 61, 编号 9 (2018)

The flotation of low-quality Russian and Mongolian coal by means of spent motor oil is investigated. Ozonization is used to improve the flotational properties of the spent oil. The optimal ozonization depth of oil used to enrich coal of poor metamorphic development is 5–6 g/kg. Ozonization increases the oil’s content of oxygen-bearing heteropolar compounds, which determine its flotation properties. In addition, the viscosity declines. The use of ozonized spent oil improves the flotation of gas coal by 24%. Flotation of naturally oxidized gas coal by spent oil, before and after ozonization, is poor and requires large quantities of reagents.

The hot strength of coke, i.e., coke strength after the reaction and cold strength of coke, i.e., M40 are foremost aspects for assessing the quality of coke for the smooth operation of the bigger blast furnaces. The hot strength of coke measured in terms of coke CSR is a time-consuming process and lengthy. The repeatability of the process for determining the coke CSR is itself high (as per ASTM 5341). Therefore, the effort is being made worldwide to develop methodology for prediction model to predict the coke CSR which can reduce the analysis time of reporting the coke CSR to blast furnace operator. In the present study, authors have developed a technique for predicting the coke strength after reaction with the help of its physical properties. The laboratory data (electrically heated 7 kg carbolite oven and 25 kg mini pilot oven) have been used for developing the model. The same has been validated with the actual recovery and non-recovery/heat recovery stamp charge coke plants data and the study confirms the inter relationship between the coke CCS and coke CRI/CSR. The newly developed technique predicts the coke CSR and CRI for recovery and non-recovery stamp charge coke plant with the help of physical properties of coke especially cold compressive strength.

Analytical methods are used to derive data regarding the yield and composition of liquid semicoking products from coal of limited metamorphic development (D, DG, and G coal). With greater metamorphic development of the coal, the yield of liquid semicoking tar increases, and the content of tar–asphaltene components in the tar rises. Chromatography combined with mass spectrometry shows that, in low-temperature pyrolysis, the liquid product formed consist of a complex mixture of saturated and aromatic hydrocarbons and heteroorganic compounds. In all the tars, normal and branched n-alkanes and n-alkenes are identified. The aromatic hydrocarbons include mono-, di-, and trisubstituted n-alkylbenzenes and alkylated naphthalenes. The heteroorganic compounds consist predominantly of oxygen-bearing compounds in the form of phenols with alkyl substituents. The different quantities of these components in the liquid products may be attributed to differences in the chemical structure of the coal’s organic mass.

Approaches to the introduction of automated coke-machine operation in coke batteries are presented.

The influence of additional inert-gas pressure on the sorptional methane capacity of Kuznetsk Basin coking coal is studied in the laboratory and in mine conditions. Creating pressure by means of a mixture of methane and helium increases the coal’s sorptional methane capacity.