Determination of the Technological Parameters of Borehole Underground Coal Gasification for Thin Coal Seams

AbstractA flow injection analysis method for spectrophotometric determination of ammonium in waters produced during underground coal gasification (UCG) of lignite and hard coal was described. The analysis of UCG water samples is very difficult because of their very complicated matrix and colour. Due to a huge content of organic and inorganic substances and intensive colour of samples (sometimes yellow, quite often dark brown or even black), most analytical methods are not suitable for practical application. Flow injection analysis (FIA) is based on diffusion of ammonia through a hydrophobic gas permeable membrane from an alkaline solution stream into an acid-base indicator solution stream. Diffused ammonia causes a colour change of indicator solution, and ammonia is subsequently quantified spectrophotometrically at 590 nm wavelength. The reliability of the results provided by applied method was evaluated by checking validation parameters like accuracy and precision. Accuracy was evaluated by recovery studies using multiple standard addition method. Precision as repeatability was expressed as a coefficient of variation (CV).

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Conditions of Suitability of Coal Seams for Underground Coal Gasification

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.844.38 ◽

2020 ◽

Vol 844 ◽

pp. 38-48

Author(s):

Gennadiy Pivnyak ◽

Volodymyr Falshtynskyi ◽

Roman Dychkovskyi ◽

Pavlo Saik ◽

Vasyl Lozynskyi ◽

...

Keyword(s):

Coal Gasification ◽

Mining Area ◽

Underground Coal Gasification ◽

Technical Documentation ◽

Gas Generator ◽

Coal Seams ◽

Experimental Development ◽

Coal Mining Area ◽

Underground Gasification ◽

National University

Results of evaluating the suitability of certain sections of Western Donbas coal seams, based predominately on properties of coal material, for their further experimental development by means of underground gasification method are represented. Criteria to evaluate both expediency of underground gasification and specific conditions of that process are substantiated basing upon the methodology developed at the National Mining University (Dnipro, Ukraine) together with representatives from National University of Saint Augustine (Arequipa, Peru). The methodology has been industrially approved with the confirmation of its efficiency while developing technical documentation for underground gasification projects: “Project of experimental section of Pidzemgaz station of Pavlogradvuhillia association”, “Feasibility study of the expediency of the construction of Pidzemgaz station” FS 3858-PZ”, Synelnykovo deposit; “Project on experimental underground gas generator”, Monastyryshche deposit, FS of experimental module of UCG station of Solenovske coal-mining area, Donbas. Also, they contain the researches, which were conducted within the project GP – 489, financed by Ministry of Education and Science of Ukraine.

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The Temperature Features of the Thermal-explosion Oxygen-steam Underground Coal Gasification in Approximately Horizontal Coal Seams

Energy Sources Part A Recovery Utilization and Environmental Effects ◽

10.1080/15567030903397933 ◽

2011 ◽

Vol 33 (16) ◽

pp. 1483-1492 ◽

Cited By ~ 4

Author(s):

L. H. Yang ◽

X. Zhang ◽

S. Q. Liu

Keyword(s):

Thermal Explosion ◽

Coal Gasification ◽

Underground Coal Gasification ◽

Coal Seams

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Preliminary modeling for module estimation on the underground coal gasification project

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/882/1/012041 ◽

2021 ◽

Vol 882 (1) ◽

pp. 012041

Author(s):

Zulfahmi ◽

M Huda ◽

B Sirait ◽

A Maulana ◽

A Lubis

Keyword(s):

Feasibility Study ◽

Coal Gasification ◽

Soil Surface ◽

Reduction Factor ◽

Underground Coal Gasification ◽

The Finite Element Method ◽

Strength Reduction Factor ◽

Maximum Deformation ◽

2D And 3D

Abstract Designing the module is one of the initial works of the underground coal gasification (UCG) feasibility study, consisting of the coal area to be gasified as panels and the coal to be left as pillars. Three models have been designed with each panel dimension 380 m in length, 150 m in width and 18 m thick. The finite element method is used in the study and the 2D and 3D geotechnical simulations have been carried out with variations of the pillars. As a result of 2D modeling, the critical strength reduction factor (SRF) is 0.25 with the highest deformation on the surface is 0.04 m (SMA-C) and 0.03 (SM-D) if the pillar is 50 m width. If SRF is increased to 0.37, the deformation on the surface is 0.36 (SMA-C) and is 13.5 (SM-D), respectively. From the 3D modeling results, if it is assumed that the velocity of the UCG reactor hole rate is 0.24 m/day until it reaches the final target length of the reactor hole 380 m, the maximum deformation of the soil surface at the SMA-C and SM-D locations is 0.074 m and 0.096 m, respectively. Determination of the module is important in the feasibility study and evaluation of the UCG site.

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