93 research outputs found
Utilization of energy crops and sewage sludge in the process of co-gasification for sustainable hydrogen production
The increasing world energy demand driven by economic growth and technical development contributes to the severe depletion of conventional energy resources and various environmental issues. The need for the employment of low-emission, highly efficient technologies of thermochemical conversion, flexible in terms of both raw resources and product applications is declared, when the utilization of solid, alternative fuels is considered. Gasification is the proven technology of lower unit emission of contaminants and higher efficiency than combustion systems, as well as versatile applicability of the synthesis gas, as its main product. While the conversion of fossil fuels in gasification systems is technically mature, the co-utilization of biomass and waste still requires research and optimization in various technical and economic aspects. In this paper, the results of experimental work on co-gasification of energy crops biomass and sewage sludge with steam to produce hydrogen-rich gas are presented. The process is performed at 700, 800 and 900°C under atmospheric pressure. The experimental results are analyzed with the application of the Hierarchical Clustering Analysis. The optimal results in terms of hydrogen production in co-gasification of selected biomass and sewage sludge are observed for Helianthus tuberosus L. blends of 10% w/w of sewage sludge content at 900°C
The Bioconversion of Sewage Sludge to Bio-Fuel: The Environmental and Economic Benefits
This paper aims to analyze the economic feasibility of generating a novel, innovative biofuel—
bioenergy—obtained from deposit bio-components by means of a pilot installation of sewage sludge
bio-conversion. Fuel produced from sewage sludge biomass bears the potential of being considered a
renewable energy source. In the present study, 23 bioconversion cycles were conducted taking into
consideration the different contents, types of high carbohydrate additives, moisture content of the
mixture as well as the shape of the bed elements. The biofuel was produced using post fermentation
sewage sludge for industrial energy and heat generation. Based on the presented research it was
concluded that the composite biofuel can be co-combusted with hard coal with the optimal percentage
share within the range of 20–30% w/w. Sewage sludge stabilized by means of anaerobic digestion
carried out in closed fermentation chambers is the final product. The average values of the CO2,
CO, NO, NOx and SO2 concentrations in flue gas from co-combustion of a bioconversion product
(20% w/w) and coal were 5.43%, 1903 ppm, 300 ppm, 303 ppm and 179 ppm, respectively. In total,
within a period of 4.5 years of the plant operation, 1853 Mg of fuel was produced and successfully
co-combusted with coal in a power plant. The research demonstrated that in the waste water treatment
sector there exists energy potential in terms of calorific value which translates into tangible benefits
both in the context of energy generation as well as environmental protection. Over 700,000 Mg of
bio-sewage sludge is generated annually in Poland. According to findings of the study presented in
the paper, the proposed solution could give 970,000 Mg of dry mass of biomass qualified as energy
biomass replacing fossil fuels
Research Collaboration Patterns in Sustainable Mining – A Co-Authorship Analysis of Publications
This article quantitatively examines the patterns of collaborative research in the field
of sustainable development of the mining sector. The study is based on bibliographic data of
4420 Scopus index research articles published in the period 1983–2018. Both trend and network
analyses were employed in this investigation. The results show a rise in the number of joint articles
and in the average number of the authors per joint article. Moreover, no increase in the relative
numbers of interinstitutional, international, and cross-sector articles was observed. The collaborative
efforts, in terms of the co-authorships, were taken mostly among authors affliated with the one
sector—namely, science and research institutions. This indicates that funding agencies should foster
more intensively the cross-sector research collaborations for sustainable mining. However, the most
collaborative countries formed cross-continental clusters, thus indicating the global character of
research collaboration for sustainable mining. This, in turn, can support solving mining issues with
long-term implications, especially the impact of the mining industry on the environment
Changes in the Distribution of Temperature in a Coal Deposit and the Composition of Gases Emitted during Its Heating and Cooling
This article presents the results of tests conducted on a measuring system for monitoring
changes in the distribution of temperature in a coal deposit during the heating and cooling phases,
and their correlation with the analysis of the concentration of gases. The tests were conducted on
five samples of hard coal collected in deposits mined in Poland. Measurements of the changes in
temperature and changes in gas concentration were conducted from the temperature of 35 to 300 C,
for the heating phase, and from 300 to 35 C, for the cooling phase. The percentage share of coal of
given temperatures was calculated. When comparing the percentage share for the same temperature
in the hot spot, for the heating and cooling phase, significant differences in the distribution of the
given percentages were observed. Changes in gas concentrations during heating and cooling were
analyzed and the dynamics of changes in gas concentrations were determined for the coals tested.
Changes in the values of fire hazard indices were analyzed. There were significant differences in
the concentration of gases and the values of fire hazard indices between the heating and the coolin
Electrochemical corrosion monitoring in low conductive fluid : pilot-scale study on sulfolane corrosion potential
Solvents are a group of chemical compounds that are widely used in organic synthesis.
Taking into account the chemical nature, solvents are divided into protic and aprotic ones. An
attractive alternative to commonly used industrial extractive liquids is an anthropogenic,
organosulfur medium—sulfolane. Sulfolane is a five-membered heterocyclic sulfur–organic
compound from the group of sulfones (R-SO2-R’, where R/R’ is alkyl, alkenyl, or aryl), which
contains an apolar hydrocarbon backbone and a polar functional group. It is a selective solvent in
the liquid–liquid and liquid–vapor extraction processes used for the removal of close-boiling
alkanes from cycloalkanes or for the separation of compounds with different degrees of saturation
and polarity in the extractive rectification of arenes from non-aromatic saturated hydrocarbon
mixtures. In standard conditions sulfolane is not an aggressive solvent for steel, but at higher
temperature (170–180 °C) and oxygen availability, it may be decomposed and subsequently some
corrosive (by-)products can be formed. The primary purpose of the presented pilot-case
examination was to verify applicability of the industrial, multi-electrochemical technique for
reliable detection of the corrosion processes in low conductive fluids
POSSIBILITIES OF MINING WASTES UTILIZATION BY THERMAL DESTRUCTION WITHIN THE UNDERGROUND GAS GENERATOR
Study the possibility of developing the technical and technological
justification of mining wastes utilization within the closed cycle of gassgene in in
economic effective level
Functional and Material Properties in Nanocatalyst Design: A Data Handling and Sharing Problem
(1) Background: Properties and descriptors are two forms of molecular in silico representations.
Properties can be further divided into functional, e.g., catalyst or drug activity, and material,
e.g., X-ray crystal data. Millions of real measured functional property records are available for drugs
or drug candidates in online databases. In contrast, there is not a single database that registers a
real conversion, TON or TOF data for catalysts. All of the data are molecular descriptors or material
properties, which are mainly of a calculation origin. (2) Results: Here, we explain the reason for
this. We reviewed the data handling and sharing problems in the design and discovery of catalyst
candidates particularly, material informatics and catalyst design, structural coding, data collection
and validation, infrastructure for catalyst design and the online databases for catalyst design. (3)
Conclusions: Material design requires a property prediction step. This can only be achieved based on
the registered real property measurement. In reality, in catalyst design and discovery, we can observe
either a severe functional property deficit or even property famine
CFD numerical modelling of a PV–TEG hybrid system cooled by air heat sink coupled with a single-phase inverter
This study presents full transient, three-dimensional numerical models of a PV–TEG hybrid
module coupled with single-phase inverter by co-simulation. The influence of factors, such as wind
speed, solar radiation intensity, or ambient temperature on the PV–TEG system, was also examined.
The numerical model was implemented using Ansys software which accounted the phenomena
of Thomson, Seebeck, and Joule’s heat place on the TEG system. Furthermore, its impact on total
electrical efficiency was studied. The heat transfer surface of the passive heat sink and forced air
circulation positively affected the total heat transfer, and therefore helped to maintain the electrical
efficiency at a higher level. Simulation of the single-phase inverter with a PV–TEG system allows
the determination of the power characteristics of the system in real time. The results of the study
presented may provide a basis for performance optimization of a practical PV–TEG-inverter hybrid
system co-design
Hydrogen rich gas production through co-gasification of low rank coal, flotation concentrates and municipal refuse derived fuel
In the paper a novel approach to thermochemical utilization of low rank coal, flotation concentrates and
municipal refuse derived fuels was presented. The economic attractiveness of low rank coals and
flotation concentrates is limited and that is why they are commonly stored at excavation heaps causing
additional costs and the risk of endogenous fires occurrence. One of the crucial parameters determining
the attractiveness and usability of a fuel in the gasification process is its reactivity. In the study several
low rank coals, flotation concentrates and municipal refuse derived fuels were tested in terms of their
reactivity in the process of steam gasification. The reactivity of low rank coal and flotation concentrates at
50% of carbon conversion, R50, varied between 1.4610 4 s 1, whereas the maximum
reactivity, Rmax, from 3.2810 4 s 1. Advanced mathematical models were developed to
investigate the similarities and dissimilarities between the studied fuels as well as the relationships
between the physical and chemical parameters and the reactivities of fuel chars in steam gasification. On
this basis, a low rank coal was selected and blended with 20%w/w of municipal refuse derived fuel in cogasification
experiments. The aim of the research was to utilize the low rank coal characterized by the
lowest reactivities (R50 and Rmax of 1.4610 4 s 1, respectively) in steam co-gasification to
hydrogen-rich gas with an alternative fuel in a fixed bed reactor at the temperature of 800 C. The
selected low rank coal was blended with 20%w/w of municipal refuse derived and the resulting fuel
yielded the average concentration of hydrogen in the produced gas of 58.99%vol
Towards intelligent drug design system: Application of artificial dipeptide receptor library in QSAR-oriented studies
The pharmacophore properties of a new series of potential purinoreceptor (P2X) inhibitors determined using a coupled neural network and the partial least squares method with iterative variable elimination (IVE-PLS) are presented in a ligand-based comparative study of the molecular surface by comparative molecular surface analysis (CoMSA). Moreover, we focused on the interpretation of noticeable variations in the potential selectiveness of interactions of individual inhibitor-receptors due to their physicochemical properties; therefore, the library of artificial dipeptide receptors (ADP) was designed and examined. The resulting library response to individual inhibitors was arranged in the array, preprocessed and transformed by the principal component analysis (PCA) and PLS procedures. A dominant absolute contribution to PC1 of the Glu attached to heptanoic gating acid and Phe bonded to the linker m-phenylenediamine/triazine scaffold was revealed by the PCA. The IVE-PLS procedure indicated the receptor systems with predominant Pro bonded to the linker and Glu, Gln, Cys and Val directly attached to the gating acid. The proposed comprehensive ligand-based and simplified structure-based methodology allows the in-depth study of the performance of peptide receptors against the tested set of compounds.NC
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