Złoże węgla brunatnego Bełchatów występuje w centralnej części równoleżnikowo przebiegającej jednostki tektonicznej zwanej Rowem Kleszczowa. Główny pokład węgla występuje na głębokości średnio ok. 130 m. Złoże eksploatowane jest metodą odkrywkową na dwóch polach eksploatacyjnych: na Polu Bełchatów i na Polu Szczerców. Pomiędzy polami eksploatacyjnymi znajduje się lokalne wypiętrzenie cechsztyńskiej soli w postaci wysadu solnego „Dębina”. Wysad wypiętrzony jest o około 350-450 m względem dna Rowu Kleszczowa i o około 60-100 m w stosunku do brzegów Rowu. Zwierciadło solne zostało nawiercone na głębokości 170 m, tj. na rzędnej +28 m n.p.m. Odwadnianie złoża, które jest niezbędnym elementem przy prowadzeniu robót górniczych wydobycia kopaliny, realizowane jest systemem studziennym od października 1975 roku na Polu Bełchatów oraz od września 2000 r. na Polu Szczerców. System odwodnienia wgłębnego składa się z barier studni: zewnętrznych, wewnętrznych stałych, wewnętrznych nadkładowych oraz systemu odwodnienia pomocniczego i studni dla odwodnienia najgłębszych partii wyrobiska wierconych na poziomach roboczych. Wystąpiła konieczność ochrony struktury wysadu solnego w związku z tym, że znalazł się na drodze wymuszonego przepływu wód podziemnych przez uruchomiony na Polu Bełchatów system odwodnienia wgłębnego. W celu zmniejszenia gradientu hydraulicznego w rejonie wysadu solnego zastosowano pierścieniową barierę studni, która powstała w latach 1990–1992 i została przebudowana w 2003 r. Zapewnienie bezpieczeństwa robót górniczych w wyrobiskach polega na przejmowaniu stałego dopływu wód spoza wyrobisk oraz utrzymaniu zwierciadła wód na rzędnych poniżej półek stałych i planowanej eksploatacji

The growing importance of using geothermal brine as an alternative source of lithium in the context of the dynamic development of new technologies is currently being pointed out. The various aspects involved need to be analyzed to consider the recovery of any element from geothermal water. The most crucial of these, after the purely technical aspects, is the legal framework of the operation. Poland and other countries have no specific legislative regulations for recovering lithium from geothermal brine, as existing activities have focused mainly on salt and heat extraction. This article presents a brief overview of the worldwide literature and the current status of legal regulations related to lithium recovery from brine in Poland. The paper focuses on selected formal possibilities for the recovery of lithium from the water of the GT-1 BIS borehole owned by Geotermia Pyrzyce sp. z o.o. The study aims to present possible legal pathways for this process. The authors also draw conclusions about the need for new regulations to recover lithium from geothermal brine. The paper contributes to the research on developing lithium recovery from unconventional sources. Furthermore, it highlights the need for an appropriate legal framework for such kind of activity not only in Poland but in other countries as well.

Abstract To study the rock cutting characteristics of spherical-tooth hob, the rock cutting process induced by the spherical-tooth hob is analyzed based on the finite element simulation and the rock cutting experiments.Then the rock breaking states, rock cutting forces and rock cutting efficiency caused by the spherical-tooth hob under different penetrations are obtained.The results show that a cutting groove and a series of pits in the cutting groove will be produced when the penetration exceeds 9 mm.At such penetration, the spherical teeth and the cutter ring can cooperate to cut rock.The cutting forces curves show obvious fluctuation and the peak va

1. ANDERSON E.M., 1951, The Dynamics of Faulting and Dyke Formation with Applications to Brit-ain, Oliver and Boyd, Edinburgh. Google Scholar

In order to solve the application problem of gob-side entry retaining formed by roof cutting (GERRC) technology of working face under goaf in close-distance coal seams, the 9101 working face and its return air roadway of Xiashanmao Coal Mine were taken as engineering background.The key parameters of GERRC were studied by means of theoretical analysis, numerical simulation and field test.The results show that: The roof cutting height (RCH) should be not less than the height of stope caving, meanwhile, when the rock strata collapsed, broke and expanded within RCH, it should meet the support effect on basic roof.And the RCH should be less than the distance between coal seams.The roof cutting angle (RCA) should meet the mechanical conditions of rock mass failure along the structural plane, and it should meet the geometric condition of not squeezing the roadway roof during the rotation and subsidence of the stope basic roof.When the RCH was 7.5m, the RCA was 15 degrees and the blasting charge structure was 4+3+3+2, the stress distribution and roof subsidence were most optimal.Three rows of constant resistance with large deformation (CRLD) anchor cables were used to strengthen roadway roof.The unit support, hydraulic prop and -shaped beam were carried out as temporary support in roadway.The surrounding rock of roadway tended to be stable when lagged behind 100m, and the effect of GERRC was good after the temporary support measures were withdrawn.

The role of flotation frothing agents in the flotation process is generally known, especially due to the size of bubbles and the stability of the foam formed.In recent years, a number of new reagents have been introduced.The purpose of this article is to present a comprehensive database containing the characteristics of surfactant families discussed using the parameter of the so called the Critical Coalescence Concentration (CCC).This article presents an analysis of the experimental data set by the author and the experimental data published in the literature.

Due to the special structures and geographical environments of the main transport roadway of underground coal mines, it is difficult to deal with accidents and rescues in cases of fire and it is easy to cause casualties and structural damage of the roadway.In this study, a roadway fire model was established using FDS software on the basis of theoretical analysis.The smoke diffusion, temperature distribution, and CO concentration distribution in a fire period were simulated under four working conditions.The results showed that the time required for the smoke layer to descend to human breathing height was positively correlated with the distance between the position and the fire source.Under the most unfavorable conditions, the smoke reached human breathing height at 15.11 s and 100 m away from the fire source.After the fire broke out, the ambient temperature in the roadway rose rapidly, and the highest temperature in the area adjacent to the fire source reached 340 .The farther away from the fire source, the lower the temperature, but it was still higher than the human body's optimum temperature (25 ) until 200 m away.The results of this study can provide a basis for the preparation of roadway fire emergency plans.