Dynamics of temperature-strength changes in the immediate roof  and formation of the gasified cavity of an underground gasifier

П.  Саик; В.  Лозинский; М.  Берник; Д.  Климов

doi:10.51301/ejsu.2026.i1.03

Авторы

П. Саик Центр китайско-европейских исследований инициативы «Пояс и путь» (BRICCES), Гуандунский университет нефтехимиче-ских технологий, Китай
В. Лозинский Национальный технический университет «Днепровская политехника», Украина
М. Берник Национальный технический университет «Днепровская политехника», Украина
Д. Климов Национальный технический университет «Днепровская политехника», Украина

DOI:

https://doi.org/10.51301/ejsu.2026.i1.03

Ключевые слова:

подземная газификация угля; выгазованное пространство; температурное поле; горные породы; прочность на одноосное сжатие; огневой забой

Аннотация

Целью работы является установление закономерностей изменения температурного поля и прочности пород непосредственной кровли под воздействием зон химических реакций вдоль огневого забоя, а также определение зависимостей формирования и изменения площади выгазованного пространства во времени в зависимости от продолжительности газификации, давления подачи дутьевой смеси и мощности угольного пласта. Исследования выполнены на лабораторной установке подземной газификации с воспроизведением продвижения фронта огневого забоя и деформаций кровли. Температуру в смоделированной непосредственной кровле регистрировали термодатчиками вдоль реакционного канала. Образцы алевролитов из непосредственной кровли пласта n₇^н шахты «Межиричанская» (ГП «Львовуголь», Украина) подвергали термообработке и испытывали на одноосное сжатие на прессе KL 200/CE-Tecnotest. Геометрию выгазованного пространства определяли по данным реперных датчиков опускания кровли, графической визуализации контуров в различные моменты времени и расчета площади методом трапеций с учетом состава и концентрации генераторного газа. Установлено, что на расстоянии 0,55 м от пласта температура в окислительной зоне (0-9 м) возрастает примерно от 323 до 550℃, в переходной зоне (9-11 м) достигает около 573℃, а в восстановительной зоне (11-30 м) снижается до ~200℃. Прочность алевролитов изменяется вдоль забоя с максимумом в районе переходной зоны и последующим уменьшением в восстановительной зоне, причем для окислительной зоны характерна экспоненциальная, а для восстановительной – логарифмическая зависимость. Показано, что площадь выгазованного пространства изменяется нелинейно, преимущественно экспоненциально, в зависимости от продолжительности газификации и мощности пласта и связана с режимом давления подачи дутьевой смеси и проявлениями обрушения пород кровли. Полученные закономерности могут быть использованы для прогнозирования параметров выгазованного пространства и оценки устойчивости кровли при обосновании управляемых режимов подземной газификации.

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