Experimental Studies and the Chemical Kinetics Modelling of Oxidation of Hydrogen Sulfide Contained in Biogas

AbstractThis paper presents the results of experimental and numerical research on the process of biogas air combustion. The purpose of the study was to determine the effect of biogas CO2 content on: (a) variations in SO2 concentrations in flue gas, (b) variations in the rates of the key reactions of oxidation of H2S to SO2.The subject of investigation were the gas mixtures: CH4/CO2 (of 25; 35 and 45 vol % CO2) with a varying hydrogen sulfide content. The experiments were conducted in a three-zone pipe furnace equipped with a swirl burner (Sg=1.26) with combustion substrate pre-mixing. It was noticed that the consumption of hydrogen sulfide was significantly reduced with the temperature decrease from 1223 K to 1023 K. The increase in the biogas carbon dioxide content inhibited the process of oxidation of H2S to SO2

Factors affecting the breeding performance of the Magpie (Pica pica) in three European cities.

The breeding biology of the Magpie (Pica pica) was studied in three European towns: Dublin 1981-1983, Zielona Góra 1984-1987 and Slupsk 1987-1988. Information was gathered on breeding success from 316 nests observed from the ground (162 Zielona Góra, 154 Slupsk), and 115 nests by direct observation of contents (93 Dublin 22 Zielona Góra

Ecophysiological determinants of the human skeletal system

This review assessed relationships between external factors and the level of joint pathology (hip, knee, ankle, elbow, shoulder, hands and feet) in humans with dysplastic arthritis, psoriatic arthritis, rheumatoid arthritis, Sjögren’s syndrome, systemic lupus erythematosus, systemic sclerosis, degenerative joint disease, ankylosing spondylitis, osteoporosis, osteomalacia and gout. The accumulation of physiologically different chemical elements in different types of bones in humans of different ages allows for a more accurate assessment of the causal quoted response from parallel biochemical systems. These allow a better understanding of the link between exposure arising from smoking, alcohol, drugs, diseases, heredity, effects of amalgam dental fillings, diet, food preferences, chemical elements, occupational and environmental exposure to toxicants, lipoperoxidation and pro-antioxidant reactions. Physiology of the osteoarticular system determines what is responsible for bone and long-term body accumulation of toxic metals, which may be involved in the pathogenesis of bone diseases. While relationships between stressors, antioxidant system and bone condition predict potential risks in certain abnormalities and change oxidative stress. Elemental instability in the environment combined with salinity, acidity, redox potential and local changes in hydrochemical balance, enhances adverse effects. Processes of remodeling and bone mineralization continue throughout life and therefore may be a determinant of long-term accumulation of toxicants. Environmental issues affecting bioaccumulation of chemical elements in the osteoarticular system in humans is poorly understood. Alloplastic procedures, including the need for prostheses, supplemented by image layouts oxidative enzyme activities, as well as lipoperoxidation and the level of stress proteins, give a complete picture of skeletal response to external stressors. Simultaneously, the analysis of the impact of stressors on bones allows a more accurate tracing of causal quoted responses from parallel reactions. They have a direct relationship with stressors and affect the nature and degree of responses and defense capabilities. Thus they have a role in the diagnosis of diseases of the skeletal system

Zmiana składu wtraceń MnO-SiO2 oraz Al2O3-MnO-SiO2 w czasie chłodzenia ciekłej stali różnej zawartości niklu : rozprawa doktorska /

Recenzenci pracy: Jan Falkus, Jan Jowsa.Praca doktorska. Akademia Górniczo-Hutnicza im. Stanisława Staszica (Kraków), 2008.Bibliogr. k. 118-122.Aktywności w układach metalurgicznych, algorytm do wyznaczenia stałych równowag reakcji odtleniania, obliczenia dla żelaza w 1873 K, dla niklu, współczynniki aktywności tlenu, manganu, krzemu, glinu, parametry oddziaływania w stopach żelazo-nikiel, metoda wyznaczenia współczynników aktywności w oparciu o model roztworu subregularnego, współczynniki aktywności zastosowane do obliczeń w kontekście innych danych zaczerpniętych z literatury, żelazo, stopy, zastosowanie stopów Fe-Ni, produkty reakcji procesu odtleniania, wpływ zawartości niklu na zdolności odtleniające Mn, Si, Al, porównanie stałych równowag w żelazie oraz stopie inwar, odtlenianie przy użyciu manganu, krzemu, glinu, zestawienie wyników, aktywności tlenków w ciekłych wtrąceniach, układ MnO-SiO2, Al2O3-MnO-SiO2, wyznaczenie równań na aktywności tlenków w funkcji temperatury, składu wtrącenia, aktywność MnO, SiO2, Al2O3, sprawdzenie dopasowania rozwinięć na aktywności do wyników z FactSage™, ewolucja składu wtrąceń w żelazie oraz stopie inwar w procesie oziębiania, metodyka obliczeń, obliczenia w układzie MnO-SiO2, wpływ lokalnego zróżnicowania stężenia manganu, wtrącenia MnO-SiO2 o budowie powłokowej, wymiana wtrąceń pomiędzy komórkami, wpływ lokalnego zróżnicowania stężenia krzemu, prognozowanie składów wtrąceń, wpływ całkowitych zawartości manganu, krzemu oraz glinu na skład wtrąceń, wpływ niskiej początkowej zawartości Al2O3 we wtrąceniach na zmianę jego ułamka molowego podczas chłodzenia, porównanie ewolucji składu wtrąceń o identycznych stanach początkowych w obu metalac

Speciation of inorganic gaseous species and condensed phases during coconut husk combustion based on thermodynamic equilibrium calculations

Thermodynamic equilibrium calculations to predict coconut husks (CH) combustion products have been carried out in this work. The selected type of biomass belongs to problematic fuels due to the fibrous structure preventing its grinding, and high chlorine content. The calculations results showed, that the combustion temperature for the tested range of 600-1000°C clearly affects the concentrations of chlorine species in the flue gas. When the temperature was below 820°C, the highest concentration had HCl(g), and above 820°C KCl(g). The chlorine was also present in ash, as KCl-NaCl-RbCl solid solution, when the combustion temperature T <700°C, and KCl-NaCl-K2SO4-Na2SO4 liquid solution, when 600 <T <960 °C. High content of chlorine in ash from CH combustion at T = 650°C has been confirmed experimentally. Speciations of inorganic gaseous species and condensed phases we investigated also during flue gas cooling from 1000 to 400°C. Major condensed phase composition were dominated by alkali metal salts in both solid and liquid phase states. Finally, we presented sixteen eutectic points for different binary systems calculated in the FactSage software

Numerical investigation of biomass fast pyrolysis in a free fall reactor

This work presents two-dimensional numerical investigations of fast pyrolysis of red oak in a free fall reactor. The Euler–Lagrange approach of multiphase flow theory was proposed in order to describe the behaviour of solid particles in the gaseous domain. The main goal of this study was to examine the impact of the flow rate of inert gas on the pyrolysis process. Calculation domain of the reactor was made according to data found in the literature review. Volume flow rates were 3, 9, 18, and 25 l/min, respectively. Nitrogen was selected as an inert gas. Biomass pyrolysis was conducted at 550◦C with a constant mass flow rate of biomass particles equal to 1 kg/h. A parallel multistage reaction mechanism was applied for the thermal conversion of red oak particles. The composition of biomass was represented by three main pseudo-components: cellulose, hemicellulose and lignin. The received products of pyrolysis were designated into three groups: solid residue (char and unreacted particles), primary tars and noncondensable gases. In this work the impact of the volume flow rate on the heating time of solid particle, temperature distribution, yields and char mass fraction has been analysed. The numerical solutions were verified according to the literature results when the flow of nitrogen was set at 18 l/min. The calculated results showed that biomass particles could be heated for longer when the flow rate of nitrogen was reduced, allowing for a greater concentration of volatile matter

Experimental studies of intermediate pyrolysis of woody and agricultural biomass in a fixed bed reactor

Biomass pyrolysis is an advanced process which leads to obtaining products as chars, primary tars and gases. Depending on pyrolysis conditions and reactor construction, the pyrolysis could be divided into three categories: slow, intermediate and fast. This work concerns the experimental analysis of an intermediate pyrolysis of biomass residues in a fixed bed reactor. As raw materials, pine bark and wheat straw were selected. Experiments were carried out at three temperatures: 400, 500 and 600 °C under constant volume flow rate of inert gas equal to 100 ml/min. Biomass samples were kept for 150 seconds in the hot zone. The main goal was to compare yields, elemental composition, and calorific values of received products under studied process conditions. The ultimate analysis of chars and organic fractions of oils was performed. Obtained results from ultimate analysis allowed to determine higher heating values by a theoretical correlation. The products of pyrolysis obtained at 600 °C characterized by the most energetic parameters. The higher heating value for organic fraction of tars was 31.62 MJ/kg while for char was 29.47 MJ/kg

Comparative Life Cycle Assessment of Catalytic Intermediate Pyrolysis of Rapeseed Meal

Biowaste valorization is a means for tackling resource depletion and climate change, which gives rise to environmental benefits and economic growth. One of the most known technological routes to convert biowaste into bioproducts is pyrolysis, which may conduct with and without catalyst application. The purpose of this study was to investigate an early-stage life-cycle assessment (LCA) for catalytic intermediate pyrolysis to valorize rapeseed meal, split over the scenarios using ZSM-5 and zeolite Y catalysts. Four selected environmental impact categories were assessed by IMPACT 2002+ methodology. The results revealed that the ZSM-5 catalytic pyrolysis led to bigger environmental impacts than the pyrolysis utilizing zeolite Y in all compared impact categories except global warming. The scenario that involved zeolite Y had around 20% GHG intensity greater than ZSM-5 pyrolysis. The bulk of GHG emissions mostly involved CO2 and methane generated from electricity consumption, which was provided by fossil resources. Applying ZSM-5 in the pyrolysis increased environmental burdens in non-renewable energy, respiratory inorganics, and terrestrial ecotoxicity by 140.88 MJ primary, 8.83 × 10−3 kg PM2.5 eq. and 125.63 kg TEG soil, respectively. The major driving factor of high value in mentioned categories was the manufacturing process of the ZSM-5 catalyst by utilizing natural gas and chemicals, such as phosphorus trichloride, sodium hydroxide and sodium silicate. Given that catalysts can play a substantial role in the emissions resulting from bio-based products, hence LCAs of pyrolysis should consider the potential influence of catalysts in the valorization processes. This study can predict environmental hotspots in the early stages of bio-waste valorization and show the potential defects of implanted biorefinery at pilot/industrial scales

The importance of grain legumes for a domestic protein security

Soya meal is the main high protein source in feeding pigs and poultry. Taking into account the annual value of domestic import, limited soya seed producers (USA, Argentina, Brasil) and China as the main soya seed importer (66 percent of the world import), a use of alternative protein sources (grain legumes, rape meal, DDGS) seems to be justified. An additional reason for a so called protein security in Poland are the feed regulations prohibiting a usage of GM products in feeding. Polish Government launched research projects for two periods (2011–2015 and 2016–2020) to solve main problems related to increased production and usage of domestic protein sources in animals feeding. Main strategies and research results of four areas – grain legume genetics and breeding, cropping technologies, pigs and poultry feeding and economic aspects of production, market infrastructure and turnover of domestic protein crops – are presented in the paper. Satisfactory is an increase of acreage under grain legumes in Poland – from 100 thousand ha in 2011 to 300 thousand ha in 2019. At present, given the availability of domestic grain legumes and rape meal it is possible to decrease soya meal imports up to 60–50 percent. Over the past decade, a strong increase of poultry meat production (about 120 percent) with a rather small increase of soya meal imports (about 18 percent) is also as optimistic tendency. A lasting solution may be achieved by setting a national/ European indicator target that would put the mandatory share of domestic protein sources in feed mixes at 10–20%, and creation of Polish feed companies, competitive to foreign, both large and mobile feed mixing plants, using the farmer’s raw materials