1/2015
Product characterization of coal pyrolysis with added mixed plastics
Sub-bituminous hard coal (Maghara, Egypt) and its mixtures with mixed plastic wastes were pyrolyzed. The main objective of the study was to produce coke and to see how the ratios of the input raw materials affect its structure. Main product yields (coke, tar, gas) were characterized by petrological and chemical methods. The prepared cokes exhibited influence of the added mixed plastics. The most advanced carbonaceous polycrystalline structure was observed in the cokes prepared from the input raw materials with the coal-to-plastic wastes ratios 90/10 and 95/5. The increasing addition of mixed plastics positively influenced composition of the produced gas and increased its calorific value.
The conversion of hydrogen and carbon dioxide to methane
In this work the theoretical foundations of the catalytic hydrogenation of carbon dioxide with hydrogen to methane, are described. Additionally the laboratory experiments carried out aiming to assess the ability of nickel-based catalyst to catalyse hydrogenation reaction as well as to assess the sensitivity of the catalyst to sulphur compounds that may be present in the reaction gas mixture, are reported. A laboratory apparatus, which was used to test nickel based catalyst for the methanation of hydrogen and carbon dioxide under different experimental conditions, was constructed. The catalyst was than deactivated using SO2 containing gas and subsequently tested in the apparatus under the same reaction conditions applied for the catalyst before deactivation. After deactivation a substantial decrease on catalytic activity for the methanation reaction, was observed. However, the catalyst can gradually regenerate in a hydrogen atmosphere. The created sulphur compounds are then gradually released along with the produced gas.
Flue gas desulphurization and denitrification using activated coke
In the process of coal treatment is produced the coal sludge. One of the usage options of this sludge is their thermal treatment and conversion to the activated coke. The options for the conversion of coal sludge on activated coke and the testing of its properties was investigated in the laboratory research, whose results are presented in this article. Waste from coal flotation was used for the laboratory production of activated coke. The obtained samples were tested for SO2 adsorption and NO removal from flue gas. The results achieved were compared with those of industrial activated coke. The wastes from coal flotation represent very good raw material for activated coke production. The activated coke samples prepared from these raw materials under laboratory conditions show similar properties as the industrially produced activated coke by Rheinbraun and Carbo Tech.
Methods of coal beds stimulation
Mining coal seam gas with high methane content requires, due to low permeability of coal seams, employment of fracturing-stimulating technologies, which ensure long-term discharge of the mined gas. In the paper, a method of hydraulic fracturing has been described, which can be realized using various fracturing fluids depending on conditions of a mined locality. Although the development of fracturing fluids and their utilization has started several decades ago, their investigation and development continues.