M. Popczyk

Changing the mining industry in the heart of Silesia

The development of coal mining in the Upper Silesian region began in the seventeenth century. Along with the development of this branch of industry, they began to form the new villages, towns and entire agglomerations in the surroundings. Even before the First World War the Polish mining industry employed over 150 thousand miners. This sector is characterized by a high degree of mechanization of work and technical progress. Miner profession from its inception was set on a pedestal by giving it a number of privileges. Mining industry introduced earliest pension and health insurance, and normalized length of the working day. Expansion of class consciousness, trade unions and political parties, resulted that the Silesia from the start was ahead of other mining and industrial regions at least by one generation. There have passed many generations from bloom years of mining to its current form of activity. At present, the global reorganization and restructuring of the industry hit also Polish mining industry.

The impact of changes in the rheological parameters of fine-grained hydromixtures on the efficiency of a selected industrial gravitational hydraulic transport system

Polish hard coal mines commonly use hydromixtures in their fire prevention practices. The mixtures are usually prepared based on mass-produced power production wastes, namely the ashes resulting from power production [1]. Such hydromixtures are introduced to the caving area which is formed due to the advancement of a longwall. The first part of the article presents theoretical fundamentals of determining the parameters of gravitational hydraulic transport of water and ash hydromixtures used in the mining pipeline systems. Each hydromixture produced based on fine-grained wastes is characterized by specified rheological parameters that have a direct impact on the future flow parameters of a given pipeline system. Additionally, the gravitational character of the hydraulic transport generates certain limitations concerning the so-called correct hydraulic profile of the system in relation to the applied hydromixture characterized by required rheological parameters that should ensure safe flow at a correct efficiency [2]. The paper includes an example of a gravitational hydraulic transport system and an assessment of the correctness of its hydraulic profile as well as the assessment of the impact of rheological parameters of fine-grained hydromixtures (water and ash) produced based on laboratory tests, depending on the specified flow parameters (efficiency) of the hydromixture in the analyzed system.