The treatment of medical wastewater by the peroxone (AOP) and electro-peroxone (E-peroxone) processes was analyzed. The E-peroxone process is based on the production of hydrogen peroxide electrochemically from an O₂ and O₃ gas mixture produced in sparged ozone generator effluent using graphite-polytetrafluorethylene cathodes. The electrogenerated H₂O₂ reacts with sparged ozone to produce hydroxyl radicals. All advanced oxidation processes presented in this study effectively removed chemical oxygen demand (COD) by up to 87%. The use of E-peroxone showed 15% better results in COD reduction than conventional peroxone. The research suggests that E-peroxone is more sufficient at removing pollutants in wastewater than peroxone. Hence, E-peroxone was found to be more cost-effective than AOP in this case.

Effective recovery of materials from construction and demolition waste (CDW) remains a major problem and a real challenge in terms of implementing the circular economy. In many countries, this waste is landfilled due to the lack of modern technological lines for its recovery and recycling, including the sorting of materials suitable for reuse. Understanding the environmental impact of the CDW treatment process is important as it constitutes the final stage of building life cycle assessment and the basis for eco-design of construction processes. In addition, the recovered materials can be used as raw materials for construction, thereby closing the waste loop and aligning with the circular economy concept. The purpose of this study is to compare the environmental impact of three different CDW recovery technologies in order to identify the optimal option. The analysis was performed using the life cycle assessment (LCA) methodology, SimaPro 8.1 software, and the Ecoinvent v3.8 database. 1 Mg of processed CDW was adopted as the functional unit. It was found that the process of recovering materials from CDW allows for sorting over 13% of materials for recycling and approx. 40% of raw materials for reuse (stone aggregates). The conducted analyses showed that all three installations exert a negative impact on the environment. Solution No. 2 had the lowest total environmental impact (15.96 Pt) under the assumptions and datasets used in this study, presenting average electricity and fuel consumption and average weight of sorted materials for recycling. Installation No. 3, which sorts the largest volume of materials for recycling, also used the most electricity; therefore, it could not be considered as the solution with the minimal overall environmental impact. The research revealed that the treatment of CDW in a crusher, applied at all installations, is the process stage resulting in the greatest environmental pressure (16.92 Pt). The high level of sorted recyclable waste enabled a relatively low carbon footprint for processes No. 2 and No. 3, 18.7 and 17.6 kg CO₂ eq, respectively (more than four times lower than for installation No. 1). Future analyses should focus on optimizing the CDW recovery process by avoiding the use of impact crushers, as adding more waste sorting equipment does not significantly enhance environmental benefits.

Most of the fuels used in internal combustion engines are liquid fuels. The magnetic behavior of fuel leads to a change in the interaction of hydrocarbon and oxygen molecules. This study aimed to evaluate the fuel consumption and engine vibration (time domain) of the Perkins A63544 diesel engine using magnetized fuel. The vibration of an internal combustion engine can cause failure in engine components and discomfort and injury to users. Engine vibration behavior changes due to changes in fuel types and engine combustion. Therefore, in this study, the vibration behavior of the tractor engine (Perkins model, four-stroke, direct injection diesel) was evaluated in stationary mode at different engine speeds due to changes in fuel types. Three accelerometers (CTC AC102 model) were used to measure the vibration acceleration. The fuels used included diesel as a normal control and fuels that had been subjected to magnetic field intensities of 1000, 2000, 3000, and 4000 gauss. The longitudinal, vertical, and lateral vibration signals with 5 levels of engine speed were measured. The results illustrated that the vibration root mean square (RMS) values were essentially (p < 0.01) affected by the engine speed, fuel type, and their interactions. It was found that for the 4000-gauss magnetized fuel, the average vibration acceleration using the five velocity settings reduced by 15%, 15.30%, 12.40%, 12.35%, and 15.38% compared to the respective control fuels. The results showed that engine fuel consumption and specific fuel consumption decreased by 2.3% using the 4000-gauss magnetized fuel compared with the normal control fuel.

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.