More cooling capacity is needed at KWK Budryk
One of the most serious hazards currently facing KWK Budryk is the climate hazard. The high temperature of the rock mass and the heat given off by operating machinery and equipment directly affect the actual working hours and the safety and health of workers. This is especially true of the work carried out in seams 405/1 and 405/2 accessed from level 1290, where the highest quality coking coal is mined. The analysis shows that in order to effectively cool one longwall in these seams, approx. 2.5 MW of cooling capacity is needed. The existing Station's capacity of only 7.2 MW is therefore insufficient.
Central air conditioning system
The surface Central Air Conditioning Station at KWK Budryk is located in the area of Shaft VI, in the immediate vicinity of the headframe. The station is equipped with compressor chillers and cooling towers. The Station produces the so-called “chilled water” which is cold water at a temperature of several degrees Celsius. The water, cooled on the surface, is transported via shaft pipelines to two levels, level 1050 and level 1290, where the water pressure is reduced in the PES-200 three-chamber-pipe feeders to transport it to individual areas. The water is then sent to coolers installed in the mining areas, where it cools down the flowing air. This lowers the air temperature in the workings. Warmed up water is returned through pipelines to the surface, where it again goes to the air conditioning station for re-cooling.
Ice slurry technology for cooling of underground workings
The mine began analyzing the possibility of expanding its air conditioning system already in 2018. Several options for increasing cooling capacity were analyzed. Among other things, expansion of the surface station with more compressor coolers, expansion of the trunk line in the shaft, or drilling wells to install additional trunk pipelines. Eventually, in cooperation with the Department of Energy and Fuels at the AGH University of Science and Technology in Kraków, a decision was made to increase the station's capacity based on ice slurry, a mixture of ice particles and water.
The main advantage of using ice slurry is that it significantly increases the so-called heat capacity of the mixture, without increasing the flow rate. The essence of this phenomenon is that the heat of melting of ice is about 80 times higher than the specific heat capacity of water. Simply put, the ice particles flowing through the pipeline heat up much more slowly than water and can carry the cold over much greater distances.
- Installations using phase conversion heat are the most modern and efficient cooling installations that have been developed to date. Adding even a few percent of ice particles to the water circulating in the central air-conditioning system makes it possible to achieve a significantly lower inlet temperature to the cooler at the end of the supply line than by using only chilled water. This results in significantly higher cooling efficiency in the workings. The air-conditioning installation using ice particles being implemented at KWK Budryk will be the first project of this type in Upper Silesia, and the second in Poland - says Kamil Adamek, project manager.
By using the technology to add ice particles to the water, maximum use will be made of the existing infrastructure, including shaft and level pipelines, and the need to build new mains will be avoided. In the underground area, it will be necessary to adapt the existing PES-200 feeders to feed the ice slurry. The technology of adding ice particles to chilled water or transporting ice as larger pieces is being used successfully in South African and Chinese mines.
- The execution of the project will allow further development of our mine. It will make it possible to mine resources of the highest quality coking coal lying at great depths. The increase in the capacity of the central air-conditioning system will directly translate into the safety and comfort of our miners and will make it possible to work in places where it would have been impossible before - says Krzysztof Baranowski, director of the Budryk mine.
A strong rationale for expanding the existing air conditioning station to include an ice slurry generation section was the air conditioning installation at the Bogdanka mine where, in August 2021, the ice particle generator was commissioned, increasing the installed cooling capacity from 6 MW to 9.1 MW. JSW representatives have visited the installation several times.
The project at KWK Budryk will be carried out by a consortium of SIEMAG Tecberg and DPMtech. Ice particle generators from the German company KTI will be used. They are used, among others, in South Africa, where they cool the gold mines.
Benefits from the implementation of the project
The expansion of the air conditioning station at Shaft VI with the use of ice particles technology will make it possible to attain the level of production assumed in the long-term plans, while maintaining the planned headcount. The comfort of the miners will be significantly improved, especially in the working faces, longwalls, longwall galleries, and air exhaust routes. It also make it possible to avoid additional working shifts. The savings will amount to tens of millions of zlotys already in the two years after the commissioning of the upgraded air conditioning station.
