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The Role of Mineral Phases in the Biogas Production Technology

Abstract

In the field of electric power industry, renewable energy sources, fertilisers, reclamation, and waste management, biomass is widely studied and used. Minerals are present in every step of biogas transformation, but their forms, occurrence, and composition have not been studied yet. However, there is no comprehensive study research that would address the presence of mineral phases in the process of biogas production. This aim of the study is determination of the amount and composition of the mineral phases present in fermentation residues resulting from different production technologies. Digestate mineral composition was analysed using 46 samples from agricultural biogas plants and university testing biogas reactor. The majority of samples contained the amorphous phase. Minority phases consisted of quartz, albite, orthoclase, muscovite, and amphibole. Opal-CT was found in eleven samples (1.26 to 12.1% wt.). The elements present in gas-liquid fluids or in liquids, gases and aerosols within the biogas technology system may create mineral phases, namely the amorphous phase or the crystalline phase under certain conditions. Opal-CT may enter the fermenter as part of plant tissues referred to as phytoliths, or as an unwanted admixture of different origin. It may also originate from the present amorphous SiO2.

Open access
The Effect of Ionic Liquids With (–)-Menthol Derivative Containing a Chloride Anion to Weed

Abstract

Weeds constitute a huge group of undesirable plants, widespread throughout the world. They represent a big problem for most farmers, who implement different methods to fight against them. Thanks to their wide occurrence, weeds however, can be an excellent indicator of the quality of soil and the whole environment where they are present. In this paper, we present the impact of four alkylimidazolium chlorides with a natural terpene component introduced into the soil: (1R,2S,5R)-(–)-menthol and alkyl substituents containing 1, 4, 9 or 12 carbon atoms, on the growth and development of selected weed species. Compounds with the highest phytotoxic activity towards gallant soldier, white goosefoot and common sorrel were chlorides with methyl and butyl substituents, while compounds with nonyl and dodecyl substituents demonstrated a weak effect on these weeds. Phytotoxicity of the salts tested was largely dependent on the applied concentration of the compound and the genetic make-up of plant species used in the experiment. This was reflected in the inhibition of plants’ length and their roots, as well as changes in the content of dry matter and photosynthetic pigments.

Open access
The Effect of Landscape on the Diversity in Urban Green Areas

Abstract

This article presented the results of a comparative analysis of carabid species compositions (Coleoptera: Carabidae) in urban green areas of the City of Lublin, Eastern Poland. In this study, the occurrence and abundance of ground beetles were analysed according to habitat preference and dispersal ability. A total of 65 carabid species were found in the three green areas. Obviously, the high species richness of ground beetles in the greenery of the Lublin is determined by the mostly undeveloped floodplain of the river Bystrzyca. The species richness of carabids and their relative abundance decrease in the assemblage of green areas under the effect of isolation of green patches and fragmentation of the semi-natural landscape elements in the urban environment. Generalists and open-habitat species significantly prevailed in all green areas. The prevailing of riparian and forest species at floodplain sites of the river Bystrzyca demonstrated the existence of a connection of the carabid assemblage with landscape of river valley. The Saski Park and gully “Rury” are more influenced by urbanization (fragmentation, isolation of green patches) and recreation that is consistent with the significant prevalence of open-habitats species in the carabid beetle assemblage.

Open access
Estimating Root Zone Moisture from Surface Soil Using Limited Data

Abstract

For estimation of root-zone moisture content from EO-1/Hyperion imagery, surface soil moisture was first predicted by hyperspectral reflectance data using partial least square regression (PLSR) analysis. The textures of more than 300 soil samples extracted from a 900 m × 900 m field site located within the Hetao Irrigation District in China were used to parameterize the HYDRUS-1D numerical model. The study area was spatially discretized into 18,000 compartments (30 m × 30 m × 0.02 m), and Monte Carlo simulations were applied to generate 2000 different soil-particle size distributions for each compartment. Soil hydraulic properties for each realization were determined by application of artificial neural network analysis and used to parameterize HYDRUS-1D to simulate averaged soil-moisture contents within the root zone (0-40 cm) and surface (approximately 0-4 cm). Then the link between surface moisture and root zone was established by use of linear regression analysis, resulting in R and RMSE of 0.38 and 0.03, respectively. Kriging and co-kriging with observed surface moisture, and co-kriging with surface moisture obtained from Hyperion imagery were also used to estimate root-zone moisture. Results indicated that PLSR is a powerful tool for soil moisture estimation from hyperspectral data. Furthermore, co-kriging with observed surface moisture had the highest R (0.41) and linear regression model, and HYDRUS Monte Carlo simulations had a lowest RMSE (0.03) among the four methods. In regions that have similar climatic and soil conditions to our study area, a linear regression model with HYDRUS Monte Carlo simulations is a practical method for root-zone moisture estimation before sowing and it can be easily coupled with remote sensing technology.

Open access
The Honey as a Bioindicator of the Environment

Abstract

Monofloral rape, sunflower, linden and acacia honeys as well as honeys sampled within and around the Austrian towns Vienna and Linz, as well as in rural areas in Lower Austria, were analysed for main and trace elements. The results were tested to be used as indication of urban dust exposure. Main elements of the ash are K, P, and B, which are specific for plant origin. Ash based data correct for dilutions by the sugar matrix. They showed enrichments of Cu, Zn and Mo, whereas the contaminant elements Cd, Pb and Co were found at about the same levels as expectable in dust. Ash-based Al, Fe, Cr and Li were much lower than soil levels obtainable from aqua regia. Among the monofloral honey samples, the effect of adjacent soil was largest for Mn. Most differences between rural areas and urban areas in Vienna and Linz were within experimental errors, both per sample weight and per ash weight. In cases honey samples are considered to trace contaminations, the additional use of ash-based data is recommended.

Open access
The Impact of Copper Ions on Oxidative Stress in Garden Cress Lepidium sativum

Abstract

Normal oxygen metabolism is an endogenous source of reactive oxygen species (ROS). The source of ROS are also many environmental factors including heavy metals. In certain concentration range, the presence of ROS is necessary to maintain proper cell function. Thus, cells have many mechanisms, which role is focused on maintaining a constant concentration of ROS. Imbalance between the formation of ROS and action of a protective antioxidant system leads to oxidative stress. This may results with a damage to the structure of proteins, lipids and nucleic acids, which in turn can lead to disturbances in the functioning of the cell and even to the death. The aim of the study was to evaluate the effect of copper ions on the metabolic activity of garden cress Lepidium sativum L. The action of copper ions with different concentrations was treated seeds. After four, six and eight days after planting in the leaves of garden cress were determined the specific activity of guaiacol peroxidase (GPOX), lipid peroxidation and protein content. Additionally intake of copper ions was determined using adsorption spectrometry technique. The results revealed that the applied doses of copper ions affected the activity of guaiacol peroxidase. The highest enzyme activity was found in plant material, which was treated with dose of copper ions 1000 mg/dm3 regardless of day. In the same samples the lowest level of lipid peroxidation was found. The highest concentrations of total proteins was found in samples treated with the highest dose of copper ions. The copper content in the tested plant material is correlated with the applied dose of copper ions. Our results indicate reliable correlations between copper content and values of oxidative stress biomarkers in plant tissues.

Open access
Microbiological and Energetic Assessment of the Effects of the Biodrying of Fuel Produced from Waste

Abstract

Biological drying (biodrying) is one of the methods of biological processing of waste, used mainly as part of the mechanical biological treatment of mixed municipal waste. Biological drying uses the heat released during the decomposition of organic matter to reduce the amount of water in dried waste. The aim of the analyses was to provide a microbiological and energetic (fuel) assessment of the process of biodrying of alternative fuel (RDF) obtained by mechanical sorting of mixed municipal waste. The resulting alternative fuel (obtained with just sorting) is characterised by varied moisture content and the presence of diverse groups of microorganisms. The analyses were intended to assess 3 alternative methods of biodrying of alternative fuel in order to produce a stable end product for utility power generation and the cement industry. The analyses were performed using special bioreactors equipped with custom (innovative) fluidised bed, aeration system (air flow rate 500 m3 · h−1), effluents drain systems, post-process air offtake and 4 temperature sensors. The assessment of the impact of the employed bed aeration methods on the quality of the alternative fuel was performed in 3 repetitions with the same external parameters. The obtained results show that after 8 days of biodrying, in the most favourable option, the moisture content in the fuel was reduced to the level of 18.7%, i.e. by 39%, the resulting fuel was microbiologically stable and the calorific value of the fuel was increased on average by 3.2 MJ · kg−1.

Open access
Performance Analysis of Crystalline Silicon and CIGS Photovoltaic Modules in Outdoor Measurement

Abstract

The outdoor measurements (during two months experiment) of photovoltaic silicon and CIGS modules as well as simulation of energy production during the period experiment are presented in this paper. This paper offer comparison of construction and electrical characteristics of multicrystalline silicon based modules and CIGS based modules. The measuring system for PV modules efficiency research is shown. The nominal power of installed modules is 250 W for m-Si and 280 W for CIGS modules. The energy production in outdoor conditions at direct current side and alternating current side of each photovoltaic panel was measured. Each PV panel was also equipped with temperature sensor for screening panel temperature. The photovoltaic panels were connected to the electrical network with micro inverters. To determine the influence of irradiance at sunshine on power conversion efficiency of PV panels, the pyranometer was installed in the plane of the modules. Measurement of the instantaneous power and irradiance gave the information about the efficiency of a particular photovoltaic panels. In the paper all data from research installation were analysed to present the influence of solar cell technology on the power conversion efficiency. The results of energy production show that m-Si module produced more energy from square meter (30.9 kWh/m2) than CIGS module (28.0 kWh/m2). Thin film module shows the higher production per kWp than multicrystalline module: 217.3 kWh/kWp for CIGS and 201.9 kWh/kWp for m-Si. The energy production simulation (made by PV SOL software and outdoor measurements test are in the good agreement. Temperature power coefficient for the CIGS module is twice lower than for the multicrystalline silicon module: 0.56%/°C and 0.35%/°C for m-Si and CIGS modules, respectively. The obtained results revealed strong influence of irradiance and temperature on energy production by PV panels. Performed studies have a large field of potential application and could improve designing process of PV installation.

Open access
The Photovoltaic Installation Application in the Public Utility Building

Abstract

The article presents the use of photovoltaic installation in a building with office space and a section for kindergarten to support the production of electricity using solar energy. Accepted technological installation solution, capital expenditures to be incurred for the project and payback time are shown. Paper presents the results of the performance simulation of the PV system adopted depending on the angle of photovoltaic panels. Designed photovoltaic installation consists of 62 panels with a total nominal power of 15.5 kW. The use of photovoltaics in the facility allow reducing carbon dioxide emissions into the atmosphere by approximately 52%. In Poland, most of the electricity produced is still based on coal and lignite. Photovoltaics is one of the renewable sources of energy, so-called “Green” energy. The investment could be made thanks to the Regional Operational Programme Podlaski, Activity 5.2 Development of local infrastructure, environmental protection 2007-2013.

Open access
Prediction of the Seasonal Changes of the Chloride Concentrations in Urban Water Reservoir

Abstract

This study investigated the possibility of using artificial neural networks to predict changes in the concentration of chloride ions in the urban ponds on the example of the inflow and outflow zones of water to and from the ponds Syrenie Stawy in Szczecin (NW-Poland). The possibility of using selected water quality indices (selected based on correlation matrix of water quality indices with Cl), in particular: COD-Cr, BOD5, DO, water saturation by O2 and NO2 and their influence on the chloride concentration forecast was tested.

Open access