A New Composite Material with Environmental Implications for Sustainable Agriculture.

Sewage sludge, also referred to as biosolids, consists of the by-products of wastewater treatment, which are a mixture of the water and organic and inorganic materials eliminated from wastewater sourced from domestic sewage industries during physical, biological, and/or chemical treatments. Biosolids are nutrient-rich organic materials resulting from the treatment of domestic wastewater in treatment plants. Sewage sludge can be considered a significant biological resource for sustainable agriculture. A new composite has been made consisting of soil, sewage sludge collected from the Galati Wastewater Treatment Plant, and slag from the Galati Steel Plant. This study aimed to investigate the structural, morphological, and chemical parameters of this composite through FTIR, SEM-EDX analysis, and XRF analysis. The samples had values of potential toxic elements that were within normal limits according to Directive 86/278/CEE, and, in terms of the iron-to-calcium ratio (I/C), all samples were of a low grade. This is the first time that slag has been added in a sewage sludge-soil combination, which can be an effective fertilizer replacement. Sewage sludge contains substantial amounts of organic matter, and slag reduces the contents of potentially toxic elements. In addition to these attributes, they may provide an opportunity for the beneficial re-use of sewage sludge and slag as resources in agriculture.

Detection of reed using cnn method and analysis of the dry reed (phragmites australis) for a sustainable lake area.

BACKGROUND: Common reed (Phragmites australis L.) is a highly productive wetland plant and a possible valuable resource of renewable biomass worldwide. For a sustainable management the exploitation of reed is beneficial because the increasing demand for sustainable biomass which presents reed bed areas and wetlands. Knowing the properties of plant biomass obtained from reeds is essential both for the effect on combustion equipment and for the impact on the environment. Brates Lake, situated in Galati, Romania is a natural watershed with reed plantations. RESULTS: We used the convolutional neural network method combined with the cropped image techniques represent a powerful tool for high-precision image-based biomass detection in lake areas. The study aimed to investigate the morphological and chemical parameters through SEM-EDX analysis and pH, conductivity, nitrate anion, nitrite anion, total nitrogen, sulphate anion, sulphide anion, phosphate anion concentrations were determined from reed extract. The samples have a moderately acidic reaction pH 4.91-4.98. The number of soluble salts in the reed extract is in the range of 3.24-4.70 g/L, the values are within normal limits, providing the plant with the necessary nutrients. CONCLUSIONS: This is the first time that neural networks are used for the detection and prediction of areas at risk for biodiversity (reduction of water gloss until it disappears, imbalances caused by keeping reeds dry in water) caused by the aggressive and uncontrolled growth of reeds.

Recycling micro polypropylene in modified hot asphalt mixture.

One of the objectives of the circular economy is solving the world's plastic pollution crisis and recycling of materials by ensuring less waste. The motivation of this study was to demonstrate the possibility of recycling two types of wastes with a high risk of pollution, such as plastic based polypropylene and abrasive blasting grit wastes in asphalt roads. The effects of adding together polypropylene based microplastics and grit waste in asphalt mixture for wear layer performance have been shown in this study. The morphology and elemental composition of the hot asphalt mixture samples before and after freeze-thaw cycle were examined by SEM-EDX and the performance of the modified asphalt mixture was determined with laboratory tests including Marshall stability, flow rate, solid-liquid report, apparent density, and water absorption. A hot asphalt mixture suitable for making wear layer in road construction, containing aggregates, filler, bitumen, abrasive blasting grit waste and polypropylene based microplastics is also disclosed. In the recipe of modified hot asphalt mixtures were added 3 proportions of polypropylene-based microplastics such as 0.1%, 0.3% and 0.6%. An improvement of the mixture performance is shown at the asphalt mixture sample with 0.3% of polypropylene. In addition, polypropylene-based microplastics are bond with aggregates from mixture well, so the polypropylene-modified hot asphalt mixture can effectively decrease the appearance of cracks during sudden temperature changes.

Waste slag benefits for correction of soil acidity.

The global trend is to find new materials with improved environment friendly. The sustainable development of 2030 AGENDA and Waste Management Legislation sustain the disposal of a large quantity of slag at landfill sites by causing environmental consequences which has drawn attention to the need for its more effective recycling. Heavy industries have been operating in the Galati area for over 30 years and an ecological education is necessary for an efficient management of waste slag. The agricultural land resources are an issue world-wide and through this investigative study we showed that the mixture of blast furnace slag and waste slag dumped in landfill can help remediation of the soil acidity and increasing the crop yield. The chemical, structural and morphological properties of three investigated different slag samples are evaluated for recycling in agriculture. Results indicated that the obtained mixture of the slag waste dumped in landfill and of granulated metallurgical slag shows its usage in saving the affected lands. Therefore, by elemental analysis determined by X-ray fluorescence analytical equipment, the optimum weight ratio for the composition of soil-slag mixture were achieved. The obtained mixture presents a balance between soil pH = 5.2 corresponding to a medium acid soil and slag pH = 12.5 which corresponds as strongly basic character which is beneficial in amelioration process of acidic soils for the improving of soil characteristics.

Important Contributions to Reducing Nitrogen Oxide Emissions from Internal Combustion Engines.

Nitrogen oxides are considered significant pollutants because of their effects on ecosystems and human health. The amount of NOx emitted by internal combustion engines can be reduced, mostly by acting on the conditions in which combustion takes place, respectively by lowering the peak flame temperature, reducing the excess of oxygen, etc. The homogeneous charge compression ignition (HCCI) engine represents a new technology that can simultaneously reduce NOx emissions and fuel consumption. This article presents these benefits of the HCCI engine by comparing the emissions and fuel consumption of a monocylinder engine when it is operated in a conventional way, with spark ignition, with those obtained when the engine is running in the HCCI mode. Moreover, since engine simulation has become an important tool for investigating the HCCI process and for developing new control strategies for it, this was used in this study to determine the effects of the exhaust gas recirculation on the combustion quality, respectively, on emissions.