The expected demand for hard coal intended for the households will progressively be decreasing. This is directly related to the introduced anti-smog resolutions, as well as the growing level of environmental awareness. However, it should be noted, that the use of the modern home heating boilers will result in an increase in the demand for medium coal sizes. The shortfall of this type of coal is already observed on the market. Therefore, its import is necessary. One of the solutions to increase the supply of the medium coal sizes is the production of coal briquettes. Moreover, their use will consequently lead to reduced emissions.

The paper presents a comparison of emissions from the combustion of coal briquettes and hard coal in home heating boilers. The briquettes were characterized by significantly lower emissions than hard coal (by 52% on average). The particulate matter emissions were lower by 70%. This may significantly contribute to improving air quality in Poland and in addition, limit the occurrence of smog. The possibility of further emission reduction by using low-emission fuels as briquette components was presented. The average relative emission reduction compared to hard coal for the analyzed fuels was estimated as follows: 62% for coal char, 57% for coke, 51% for charcoal/biocarbon, 49% for anthracite, 45% for torrefied biomass, and 33% for peat.

Furthermore, the issue of the mercury content in the analyzed fuels was discussed. The lowest mercury content was found in biomass fuels, in particular biomass after thermal treatment (torrefied biomass, biocarbon, and charcoal). Fuels produced from hard coal in the pyrolysis process (coal char and coke) were characterized by very low mercury content as well.

In the process of determining the content of impurities, including fossil fuels, crude oil, coke, pitch, plastics, glass, slag, rust, metals, and rock dust, in charcoal and wood briquettes via microscopic examination, the question of the use of ashes from the combustion of grill fuels (taking the scale of the new national sport into account, commonly referred to as „weekend grilling”) was raised. Another reason for addressing this issue was the question regarding the use of organic additives to acidified soil (mineral) fertilizers submitted by one of the clients of the bituminous coal and reservoir rocks analysis laboratory. In addition, the manufacturer of gardening soil has also expressed an interest in an unconventional deacidifying agent; the introduction of a new product with a unique ingredient is considered as a chance to stand out from the competition. A review of the literature shows that attempts to use ashes obtained from the biomass combustion in power boilers have been made. However, due to the biomass composition and additives and pollutants used in biomass for energy purposes, the production of such mixtures has been dropped. Based on the data from numerous samples of grill fuel, which meet the requirements regarding the content of impurities set out in the PN-EN 1860-2 standard, the question of the possible use of ash obtained from charcoal and wood briquette grilling as a component for use in the production of acidified soil (mineral) fertilizers was discussed. The article will present the amount of material obtained based on the statistical sales of barbecue fuels based on the experimentally calculated ash mass resulting from the combustion of 1 kg of starting material. In addition, a logistic proposal for obtaining ash from individual grill users will be developed. On the day of the submission of the present work, the results of the chemical analysis of charcoal and wood briquettes subjected to the gasification process have not yet been obtained. However, based on the microscopic analysis, it can be concluded that the content of impurities in the examined samples is highly unlikely to prevent the use of the mentioned ashes in agriculture.

Foundry dust from blasting and grinding of castings contain a high amount of iron, ergo it is possible its recycling in foundry process. Dust was compacted by briquetting, two kinds of briquettes were prepared (A contained 95% magnetic part of dust from casting blasting +5% bentonite and B contained 95% mixture of dust from casting grinding and magnetic part of dust from casting blasting + 5% bentonite) and used as a part of charge into the electric induction furnace. It was found that addition of briquettes has had an influence of a chemical composition of cast iron above all on content of sulphur, phosphorus and silicon. It was not reflected in decrease in tensile strength and in microstructure. Yield of metal from briquettes was not lower then 70%.

Sapropel deposits are widely distributed around the globe. In the Americas area they are adjacent to the Great Lakes region, in Europe sapropel deposits can be spotted in the territory of Scandinavia, France, Switzerland, Germany, Poland, Belarus, Russia and in the northern regions of Ukraine. Use of sapropel as a fertilizer can enhance high and stable yields of crops. However, despite the proven effectiveness of long-term practical researches in this area, nowadays sapropel is almost not used. One of the reasons - lack of developed processing methods of extraction and processing, including dehydration. Material properties as an object of interaction with the working bodies, change of their settings in the processing are crucial in the choice of technologies, development, bringing up to the necessary parameters and subsequent use. Sapropel high humidity (95-98%) is one of the main factor that determines the quality of its properties after the interaction with working bodies. However, in the process of decreasing, in interaction with oxygen, there are significant changes in physical and mechanical properties of sapropel. Decisive in the direction selection process of lake sapropels’ use in the economic sector is their moisture exchange and thermodynamic parameters. The complexity of setting the water apart, if freshly extracted sapropels possess only 15-20% of it, shows their strong water-retaining capacity. The above mentioned phenomenon proves the need for their use as an organic fertilizer during the crops growing, as superficial loss of moisture in the soil creates a new global problem. On the basis of deep analysis of the sapropels’ properties, the authors suggest three areas of freshly extracted lake sapropel application in mixtures with leafy part of the crops: in biogas production with its further use as an organic fertilizer; making a compost mixture of organic origin which physical and mechanical properties are approximate as that of the soil; alternative solid fuels in the form of briquettes.