This paper represents the results of experimental studies of physical modeling of the underground coal gasification process in terms of implementation of design and technological solutions aimed at intensification of a gasification process of thin coal seams. A series of experimental studies were performed in terms of a stand unit with the provided criteria of similarity to field conditions as well as kinetics of thermochemical processes occurring within a gas generator. Hard coal (high volatile bituminous coal) was selected as the raw material to be gasified, as that coal grade prevails in Ukrainian energy balance since it is represented by rather great reserves. Five blow types were tested during the research (air, air–steam, oxygen–steam, oxygen–enriched, and carbon dioxide and oxygen). As a result, the effect of tightness of a gas generator on the quantitative and qualitative parameters of coal gasification while varying the blow by reagents and changing the pressure in a reaction channel has been identified. Special attention was paid to the design solutions involving blow supply immediately into the combustion face of a gas generator. The experimental results demonstrate maximum efficiency of the applied gas generator design involving flexible pipelines and activator in the reaction channel and a blow direction onto the reaction channel face combined with blow stream reversing which will make it possible to improve caloricity of the generator gas up to 18% (i.e., from 8.4 to 12.8 MJ/m3 depending upon a blow type). Consideration of the obtained results of physical modelling can be used with sufficient accuracy to establish modern enterprises based on the underground coal seam gasification; this will help develop more efficiently the substandard coal reserves to generate heat energy as well as power-producing and chemical raw material. The research conclusions can provide technical reference for developing a new generation of underground coal gasification technology.
Bibliographical noteFunding Information:
2.3.1.The Experimentalexperimental standStand Unitunit is designed and patented at Dnipro University of Technology, and manufactured by Naftomash RMA under financial support of the Ministry of The experimental stand unit is designed and patented at Dnipro University of Tech- Education and Science of Ukraine. nology, and manufactured by Naftomash RMA under financial support of the Ministry of A gas generator model consists of four systems (Figure 1): – AAn expergas generatorimental modelstand; consists of four systems (Figure 1): A system of supply of separated and mixed blow mixture (blow reagents, see Section A2.s3y.3s)t;em of supply of separated and mixed blow mixture (blow reagents, see Section 2.3.3); A gas outlet system; A system of control and measuring equipment (temperature control and control of input and output gas mixtures). input and output gas mixtures).
Funding: This study was carried out as part of the project “Belt and Road Initiative Institute for Chinese-European studies (BRIICES)” and was funded by the Guangdong University of Petrochemical Technology.
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- Coal gasification
- Coal seam
- Heat balance
- Material balance