Using Geiger Dosimetry EKO-C Device to Detect Ionizing Radiation Emissions from Building Materials.

The purpose of the article is to check and assess what radiation is emitted by particular building materials with the passage of time. The analysis was performed with the EKO-C dosimetry device from Polon-Ekolab. The scope of the work included research on sixteen selected construction materials, divided into five groups. The analysis of the results showed that samples such as bricks (first group) and hollow blocks (second group) emit the highest radiation in the tested objects. When comparing these materials, the highest value was recorded when measuring the ceramic block of 15.76 mSv·yr-1. Taking into account the bricks, the highest value of radiation was shown by a full clinker brick, 11.3 mSv·yr-1. Insulation materials and finishing boards are two other groups of building materials that have been measured. They are characterised by a low level of radiation. In the case of materials for thermal insulation, the highest condition was demonstrated by graphite polystyrene of 4.463 mSv·yr-1, while among finishing boards, the highest value of radiation was recorded for the measurement of gypsum board of 3.76 mSv·yr-1. Comparing the obtained test results to the requirements of the Regulation of the Council of Ministers on ionizing radiation dose limits applicable in Poland, it can be noted that the samples examined individually do not pose a radiation risk to humans. When working with all types of samples, the radiation doses are added up. According to the guidelines of the regulation, the total radiation dose does not exceed 50 mSv·yr-1 and does not constitute a threat to human health.

Possibility of Using Waste Materials as Substitutes for Gravel or Water in Concrete Mix.

Analyzing the global waste management sector, we can see that some waste, due to its specificity, is a major challenge when it comes to its management. This group includes rubber waste and sewage sludge. Both items pose a major threat to the environment and human health. The remedy for this problem may be the solidification process, in which the presented wastes are used as substrates in the production of concrete. The aim of this work was to determine the effect of waste addition to cement in the form of an active additive (sewage sludge) and a passive additive (rubber granulate). An unusual approach to sewage sludge was used, which was introduced as a substitute for water, and not, as in most works, sewage sludge ash. In the case of the second waste, commonly used tire granules were replaced with rubber particles resulting from the fragmentation of conveyor belts. A wide range of the share of additives in the cement mortar was analyzed. The results for the rubber granulate were consistent with numerous publications. For the addition in the form of hydrated sewage sludge, the deterioration of the mechanical properties of concrete was demonstrated. It was found that the flexural strength of the concrete in which water was replaced with hydrated sewage sludge was lower than that of the sample without the addition of sludge. The compressive strength of concrete with the addition of rubber granules was higher than the control sample and did not significantly depend on the amount of granulate used.

Effect of the Application of Sunflower Biochar and Leafy Trees Biochar on Soil Hydrological Properties of Fallow Soils and under Soybean Cultivation.

Soils enriched with biochar are recommended as a cultivation grounds, especially in case they contain significant amount of sand. However, the interactions between biochar and plants, as well as the influence of the biochar on water retention, cultivation and air properties of soils, are still not obvious. The present study aimed to determine the impact of various biochar doses on soils used for soya cultivation, in comparison to soils maintained as black fallow soil, on their water retention and productivity, for the period of two years. Sunflower husk biochar (BC1) and biochar of leafy trees (BC2), in doses of 0, 40, 60, 80 t·ha-1, were used for field experiments. The water retention was investigated with porous boards in pressure chambers by a drying method. No differences in the hydrological properties of the soils that were differently managed (black fallow soil, crop) were observed following biochar application. Addition of BC1, in the amounts of 40, 60, and 80 t·ha-1, caused an increase in the plant available water capacity (AWC) by 15.3%, 18.7%, and 13.3%, respectively, whereas the field capacity (FC) increased by 7.4%, 9.4%, and 8.6% for soils without biochar. Application of BC2 analogously resulted in higher AWC, by 8.97, 17.2%, and 33.1%, respectively, and higher FC by 3.75, 7.5%, and 18.3%, respectively. Increasing the doses of BC1 and BC2, both on black fallow soils and soils enriched with soya, caused a rise in total porosity (TP) and drainage porosity (DP), and a decrease in soil bulk density (SBD). Biochar with a higher total area and higher porosity (BC1) applied to soils with soya cultivation resulted in lower reductions in AW and FC than BC2 in the second year of investigation.

Impact of digestate addition on the biostabilization of undersized fraction from municipal solid waste.

Biostabilization is a commonly applied method in mechanical-biological treatment (MBT) plants to process municipal solid waste. In many ways, e.g. by applying additives to waste, MBT plant operators strive to enhance the effectiveness of biostabilization, which leads to reducing the time and energy outlays necessary for the process, as well as to minimizing the amount of final stabilized waste directed to landfills. This paper deals with the impact of digestate waste from agricultural biogas plants used as additive to the biostabilization process of undersized fraction from municipal solid waste (UFMSW) on the intensive phase of the process and properties of stabilized waste. The aim of this study was to assess whether, and if so to what extent, the application of digestate waste affects the process. Five different input compositions were tested (without digestate and with the addition of digestate at: 2.5; 5; 7.5 and 10 wt%). Waste treatment time was 2 weeks. Changes in moisture content, organic matter (OM), respiration activity (AT4), bulk density, air-filled porosity, heavy metal content, pH, carbon to nitrogen ratio, as well as composition of process gases emitted were evaluated. Additionally, microorganisms (including pathogens) inhabiting the processed waste in the aspect of waste sanitation were analyzed. It was found that the addition of digestate at 2.5, 5 and 7.5 wt% extended the duration of the thermophilic phase and decreased the CO2 content in process gases. The addition of digestate at 2.5 wt% and 5 wt%, decreased also OM by approx. 25% of the initial value and AT4 by approx. 30%. It was also proved that the addition of digestate favors the limited sanitation of UFMSW. As a result of the research, it was found that the addition of digestate at 2.5 wt% and 5 wt% is sufficient to accelerate the aerobic biological degradation of UFMSW.