Households are the most significant group of consumers in the municipal and household sector in Poland. In 2010-2016, households consumed annually from 8.9 to 10.8 million Mg of coal (77-81% share in this sector). As of the beginning of 2018, seven voivodships in Poland have already introduced anti-smog resolutions, one has its draft, three are considering introduction of such resolutions. In the face of introducing anti-smog resolutions, the analysis of coal consumption by households was conducted for a situation where anti-smog resolutions will be introduced in all voivodships in Poland. A forecast of hard coal consumption by Polish households in 2017-2030 was presented in the article. Two scenarios differentiated in terms of calorific value of coal were taken into account: (i) concerned coal with a calorific value of 24 MJ/kg (min. Q for eco-pea coal: grain size 5.0-31.5 mm), (ii) – coals with a calorific value of 26 MJ/kg (Q recommended for use by producers of class 5 boilers). In the perspective of 2030, the largest decrease in hard coal consumption can be expected (jointly) in the voivodships of Śląskie, Dolnośląskie, Opolskie and Lubuskie. Under the assumptions made, in relation to 2016, it may be reduced by half and fall from 2.8 to the level of 1.4-1.5 million Mg. The smallest decreases in consumption may occur (jointly) in the Małopolskie, Lubelskie, Podkarpackie and Świętokrzyskie voivodships – decrease by 16-22% and fall from 2.6 to approximately 1.9-2.0 million Mg. On a national scale, coal consumption may decrease from the current 10.4 (2016) to around 6.3-6.8 million Mg (a decrease of 30-35%). Despite the decrease in hard coal consumption in the 2030 perspective, one should expect an increase in demand for high quality coal dedicated to modern boilers (usually pea assortments) as well as qualified coal fuels (mainly eco-pea coal).
The aim of this paper is two-fold. First, some basic notions on acoustic field intensity and its measurement are shortly recalled. Then, the equipment and the measurement procedure used in the sound intensity in the performed research study are described. The second goal is to present details of the design of the engineered 3D intensity probe, as well as the algorithms developed and applied for that purpose. Results of the intensity probe measurements along with the calibration procedure are then contained and discussed. Comparison between the engineered and the reference commercial probe confirms that the designed construction is applicable to the sound field intensity measurements with a sufficient effectiveness.