The main advantage of standard gas sampling methods is their capability to keep a consistent gas composition from sampling to the analysis. On the other hand, the disadvantages include the price and possible fragility of the sampling... more
The main advantage of standard gas sampling methods is their capability to keep a consistent gas composition from sampling to the analysis. On the other hand, the disadvantages include the price and possible fragility of the sampling equipment and the speed of sampling. Thus, a new tool was required with low cost and fast sampling during fieldwork. Disposable plastic syringes fulfill all these requirements with the additional advantage of applicability for multiple samplings. With the utilization of 3-way stopcocks, a filter media, and a butterfly needle, a simple but efficient sampling system was prepared. Even though the holding time of specific components is not as high as it is for a standard sample holder, the precise analysis of the gas samples is possible. After 3 hours of holding time, the concentration decrease was 0.4% CO, 1.6% CO2, 8.0% H2, 0.2% CH4, 0.5% C2H4, 0.8% C2H6, 3.5% H2S (3-part syringe) and 2.5% H2S (2-part syringe) In the article, equations are proposed for the examined components so that the measured concentrations could be adjusted based on the elapsed time from sampling. Syringes have been successfully utilized in the field of applied pyrolysis, for small and pilot-scale experiments, and can even be used in an industrial environment.
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Pyrolysis is a thermochemical process used to produce utilisable materials of various phases. The energy efficiency of the canteen waste pyrolysis can be increased with the addition of oak, so a 2:1 mixture of oak and canteen waste was... more
Pyrolysis is a thermochemical process used to produce utilisable materials of various phases. The energy efficiency of the canteen waste pyrolysis can be increased with the addition of oak, so a 2:1 mixture of oak and canteen waste was pyrolysed. To examine the efficiency of catalysts on the co-pyrolysis, the mixture was pyrolysed with and without catalysts. The catalysts used were calcined dolomite, calcined zeolite and NaCl, in 5 wt%. The process was examined with laboratory experiments and thermogravimetric (TG) method. The catalysts increased the base material conversion and gas yield. There was no significant change in the H2/CO ratio. The high heating value of the samples with NaCl and calcined dolomite significantly improved. The residual carbon of the samples with catalysts decreased, compared to the original mixture. The effects of calcined zeolite and NaCl can be observed at low temperatures but the effects of calcined dolomite appear at 650°C.
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Beside of industry, agriculture, and transport, primarily the solid combustion plants used by households are responsible for the emission of gaseous and solid pollutants in ambient air. Thus, the actual reduction of air pollutant... more
Beside of industry, agriculture, and transport, primarily the solid combustion plants used by households are responsible for the emission of gaseous and solid pollutants in ambient air. Thus, the actual reduction of air pollutant concentration also can be achieved by regulating of residential heating. New, solid-fired, individual room heating systems will have to meet stricter emission requirements from 1 January 2022. People in poorer regions are not able to buy new equipment, so in most households old equipments in poor condition remain in use. In addition, the population – albeit illegal – in most cases also burn the combustible waste generated in the households in their stove or boiler, which further increases the amount of air pollutant emissions. So far the authorities cannot be to clearly demonstrate the combustion of waste from the flue gas and residual ash, because these methods are expensive and hardly unworkable, as the authorities find it difficult to get into private homes.
Research Interests: Combustion, Air Pollution and Health Effects, GHG Emissions, Solid fuels combustion, NOx emissions, and 10 moreSOx emissions, Greenhouse Gas Emissions, PM10, Polycyclic aromatic hydrocarbons (PAHs), PM10 Particulate Matter, Particulate Matter, PM2.5, PM10 emission, residential PM2.5 emissions, and PM2.5 emissions
Thermal pyrolysis of HDPE, LDPE, PP and PS plastic wastes were performed in a batch reactor and the yields of pyrolysis oils and liquid transportation fuels prepared by atmospheric distillation were determined. The gasoline fractions were... more
Thermal pyrolysis of HDPE, LDPE, PP and PS plastic wastes were performed in a batch reactor and the yields of pyrolysis oils and liquid transportation fuels prepared by atmospheric distillation were determined. The gasoline fractions were tested in a traditional spark-ignition engine without any modifications or fuel blending. Fuel consumption and exhaust gas emission (NOx, CO) were measured and compared to a commercial fuel (RON = 95). PS generated 70.5% gasoline range hydrocarbons from the solid waste, followed by PP with 42.1%, LDPE with 40.8% and HDPE with 37.3%. The fuel consumption was reduced by 9.1-9.4% in the case of PS compared to reference measurement. Reduction in fuel consumption was noticeable at HDPE, LDPE and PP as well. PS gasoline decreased by 91-96%, while HDPE, LDPE and PP more likely increased the CO emission of the engine compared to commercial gasoline. The results show that pyrolysis of plastic wastes is a promising method to generate value added liquid transportation fuels and reduce the footprint of waste accumulation in landfills.
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Three mixture of catering waste was pyrolyzed at 650, 725 and 900 °C and the solid residue (coke) was examined for powdered activated carbon production. For this, the carbon content, iodine number, particle size distribution and scanning... more
Three mixture of catering waste was pyrolyzed at 650, 725 and 900 °C and the solid residue (coke) was examined for powdered activated carbon production. For this, the carbon content, iodine number, particle size distribution and scanning electron microscopic images were analysed. Based on the carbon content, these cokes are suitable for activated carbon production, which were 60-85 wt.% (depending on the base material and pyrolysis temperature). The studied cokes showed slightly porous structure with smooth surfaces. Because of this, the iodine number was mostly small (13-30). Based on the grinding experiments, 10 minutes of grinding was found to be optimal. After this grinding time, the reached iodine number of powdered activated carbon was 350-610.
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Biogas was produced from sheep manure and two types of submerged aquatic plant (Vallisneria spiralis and Egeria densa). The gas cleaning was carried out by a water scrubber, where a significant part of CO2 and H2S can be separated from... more
Biogas was produced from sheep manure and two types of submerged aquatic plant (Vallisneria spiralis and Egeria densa). The gas cleaning was carried out by a water scrubber, where a significant part of CO2 and H2S can be separated from the gas. A part of water from the scrubber was circulated through an aquatic plant growth tank and the growth of used plants was examined. Addition of E. densa to sheep manure increased gas yield by 8% and the mixing of sheep manure and V. spiralis resulted in 21% increase in gas yield. With the used scrubber, 70-80 vol% methane content can be reached in the cleaned biogas, and the water from the scrubber (which contained dissolved CO2 and H2S) resulted in 56-87% increase in size as opposed to 12-44% increase in the control group.
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The fact that freshwaters are becoming affected increasingly by a wide range of stressors, mainly because of various human activities, is acknowledged by many national and international organizations. Thus, not only the protection and... more
The fact that freshwaters are becoming affected increasingly by a wide range of stressors, mainly because of various human activities, is acknowledged by many national and international organizations. Thus, not only the protection and quality management of natural waters but the examination and identification of the origin of the contaminants are relevant research topics. In the article, the main correlation between the anthropogenic activities and stream water quality are observed in case of Kácsi Stream in Northeast Hungary. Based on the chemical properties and contaminants, it can be stated that mainly the agricultural effects can be observed on the water quality. Furthermore, the use of fertilizers with different compositions can also be detected.
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Az elkövetkező időszakban a megújuló energiahordozók fokozott hasznosítása várható, amely a fosszilis energiahordozók felhasználását igyekszik kiváltani. Hazánkban a természeti adottságok miatt várhatóan a biomasszák kerülnek előtérbe.... more
Az elkövetkező időszakban a megújuló energiahordozók fokozott hasznosítása várható, amely a fosszilis energiahordozók felhasználását igyekszik kiváltani. Hazánkban a természeti adottságok miatt várhatóan a biomasszák kerülnek előtérbe. Kutatásaink során a biomasszán túl egyéb megújuló energiaforrások alkalmazhatóságát vizsgáltuk, és egy kis-település, Csernely példáján keresztül mutatjuk be a benne rejlő lehetőségeket.
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Az étkezdei hulladékokat a hazai gyakorlatban részben kommunális hulladékként kezelik, részben pedig ártalmatlanítják, ezzel szemben elgázosítással értékes energiahordozó is kinyerhető belőlük. A jó hatásfokú elgázosításhoz az alapanyag... more
Az étkezdei hulladékokat a hazai gyakorlatban részben kommunális hulladékként kezelik, részben pedig ártalmatlanítják, ezzel szemben elgázosítással értékes energiahordozó is kinyerhető belőlük.
A jó hatásfokú elgázosításhoz az alapanyag vizsgálata szükséges, amelynek segítségével meghatározhatók az étkezdei hulladékok azon jellemzői, amelyek az elgázosításhoz szükségesek.
A jó hatásfokú elgázosításhoz az alapanyag vizsgálata szükséges, amelynek segítségével meghatározhatók az étkezdei hulladékok azon jellemzői, amelyek az elgázosításhoz szükségesek.
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A significant part of the food produced in developed countries becomes waste. One possibility of energy recovery from food waste is the usage of thermochemical processes in which synthesis gas can be produce. In this article, we present... more
A significant part of the food produced in developed countries becomes waste. One possibility of energy recovery from food waste is the usage of thermochemical processes in which synthesis gas can be produce. In this article, we present the specific amount and the composition of produced synthesis gas produced during the pyrolysis and the elemental composition of the residual of the pyrolysis. The presented research also covers the possibility and necessity of combined gasification of food waste and wood.
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Világviszonylatban a megtermelt élelmiszerek jelentős része hulladékként végzi, ami a világ fejlettebb országai esetén sokkal erőteljesebben jelentkezik. Az élelmiszer hulladékok egy lehetséges hasznosítási formája lehet a pirolízis,... more
Világviszonylatban a megtermelt élelmiszerek jelentős része hulladékként végzi, ami a világ fejlettebb országai esetén sokkal erőteljesebben jelentkezik. Az élelmiszer hulladékok egy lehetséges hasznosítási formája lehet a pirolízis, amely során további hasznosítható szilárd, folyadék és gáz halmazállapotú termékek keletkeznek. Ezen hulladékok felhasználásának gazdaságosabbá tétele érdekében kisebb nedvesség tartalmú tölgyfával kevertük és a keveréket pirolizáltuk. A folyamatokat katalizátorokkal segítettük, amit laboratóriumi reaktorban végzett kísérleteken és derivatográfos vizsgálatok eredményein keresztül hasonlítottunk össze.
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Szerves hulladékok keletkeznek az állattartó telepeken felhalmozódó trágya formájában, az élelmiszeriparban, a vágóhídi és a növényi termékeket feldolgozó konzervgyárakban, az ipari és kommunális szennyvíztisztító telepeken és a szilárd... more
Szerves hulladékok keletkeznek az állattartó telepeken felhalmozódó trágya formájában, az élelmiszeriparban, a vágóhídi és a növényi termékeket feldolgozó konzervgyárakban, az ipari és kommunális szennyvíztisztító telepeken és a szilárd kommunális hulladékok lerakóiban. Ezeknek a hulladékoknak az ártalmatlanítása nagy költséggel járó feladatot jelent világszerte. Elgázosításuk és energetikai hasznosításuk klímavédelmi szempontból is előnyös.
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A Miskolci Egyetem Tüzeléstani és Hőenergia Intézeti Tanszékén évek óta folynak szintézisgáz előállítással kapcsolatos kutatások különböző anyagok felhasználásával. A cikkben ételmaradékok kigázosításához keresünk olyan kiegészítő... more
A Miskolci Egyetem Tüzeléstani és Hőenergia Intézeti Tanszékén évek óta folynak szintézisgáz előállítással kapcsolatos kutatások különböző anyagok felhasználásával. A cikkben ételmaradékok kigázosításához keresünk olyan kiegészítő alapanyagot, amellyel gazdaságosan megvalósítható a folyamatos üzem. Ehhez a termoanalitikai vizsgálataink eredményeit vesszük alapul.
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A possible increase in biogas production and utilisation can be expected in the next decades. The direction of the utilisation of biogas made from animal manure is cogeneration. During our research we examined biogas potential, which is... more
A possible increase in biogas production and utilisation can be expected in the next decades. The direction of the utilisation of biogas made from animal manure is cogeneration. During our research we examined biogas potential, which is the result of biochemical processes, through an example of a pig farm.
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This paper studies the physical and chemical properties of different types of food substance generally involved in the daily menu of a university canteen. The data obtained from proximate analysis (i.e. elemental composition, moisture and... more
This paper studies the physical and chemical properties of different types of food substance generally involved in the daily menu of a university canteen. The data obtained from proximate analysis (i.e. elemental composition, moisture and ash content) suggest that the tested food samples are suitable for synthesis gas production but should be mixed with dry matter from additional resources to make the process commercially viable.
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The emission of contaminants is determined by the structure of the national production and consumption, the quality and quantity of fuels used, the applied technologies, the transportation system and the demand for mobility. The amount of... more
The emission of contaminants is determined by the structure of the national production and consumption, the quality and quantity of fuels used, the applied technologies, the transportation system and the demand for mobility. The amount of emitted contaminants has radically decreased during the past century. The contribution of each sector to air pollution has significantly changed as well. The tendencies characteristic to the Northern Hungarian region can only be determined based on long-term monitoring.
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During the research, the aim was the expansion of the potential of coal gasification and pyrolysis by the production of synthesis gas that can be used as a chemical raw material. Controlling the process of the pyrolysis experiment can be... more
During the research, the aim was the expansion of the potential of coal gasification and pyrolysis by the production of synthesis gas that can be used as a chemical raw material. Controlling the process of the pyrolysis experiment can be challenging. The temperature control of the process on its own is not enough to alter the composition of the produced synthesis gas, especially if all reactions take place in a single stage. The main objective of our research is to separate the low temperature and high temperature pyrolysis, and gain additional control over the whole process. Two separate reactors were connected through a still pipe that could allow gas flow between them, and they were inserted in two independent temperature controlled furnaces. Even though synthesis gas produced at low temperatures has high methane quantity, this perhaps can be thermally decomposed by forcing it through the high temperature zone of the experiment setup. The prospects of this setup have been investigated detailing the gasifier setup. The results of experiments will also be discussed in this article.
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During the experiments, the material and energy conversions during the pyrolysis of Hungarian low rank coal at low (450 °C) and high temperatures (900 °C), and the residue char and liquid phase were examined. Temperature increase results... more
During the experiments, the material and energy conversions during the pyrolysis of Hungarian low rank coal at low (450 °C) and high temperatures (900 °C), and the residue char and liquid phase were examined.
Temperature increase results in higher material and energy conversion. Thus, the amount of solid residue decreases and the energy content of the final product is higher. Despite this, char with significant carbon content – and calorific value – is produced during the experiments at 900 °C which may be further utilised.
Temperature increase results in higher material and energy conversion. Thus, the amount of solid residue decreases and the energy content of the final product is higher. Despite this, char with significant carbon content – and calorific value – is produced during the experiments at 900 °C which may be further utilised.
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Microcontrollers have been around for almost five decades now. They have been and are still used in almost every consumer electronics since their first appearances in the calculator war of the 70’s and 80’s between the biggest names in... more
Microcontrollers have been around for almost five decades now. They have been and are still used in almost every consumer electronics since their first appearances in the calculator war of the 70’s and 80’s between the biggest names in electronics. However, their use was limited as their programming language was difficult and one had to be an expert in electronics and had to spend a large amount of funds just for basic programming equipment. Their cost and accessibility overcame their advantages for use in prototyping and research. In the last decade though, a platform emerged, with all the key features needed to make it popular and accessible. It is easy to program, ccessible and very low priced. One of the most popular of these microcontroller boards are the Arduinos. In this paper, a working example of the implementation in our two-stage pyrolysis experiment will be presented discussing in detail the hardware and the software setup.
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One of the possible utilisation methods for organic wastes is anaerobe decomposition (fermentation). The main product of this process is biogas which is usually used for energy purposes due to its composition (mainly methane and carbon... more
One of the possible utilisation methods for organic wastes is anaerobe decomposition (fermentation). The main product of this process is biogas which is usually used for energy purposes due to its composition (mainly methane and carbon dioxide). The residual solid material after fermentation can be used as soil conditioner.
Lab-scale fermentation can be carried out using the “VDI 4630 – Fermentation of organic materials Characterisation of the substrate, sampling, collection of material data, fermentation tests” standard. Based on the conditions described in the standard, a small-scale low-budget reactor system were prepared. The temperature during the holding time was controlled with water bath and the gas production was determined with fluid displacement method. A peristaltic pump was used for the recirculation of the gas to mix the base material. Furthermore, the temperatures of the environment, the water baths and the inside of each reactor was automatically registered on a data collector.
Lab-scale fermentation can be carried out using the “VDI 4630 – Fermentation of organic materials Characterisation of the substrate, sampling, collection of material data, fermentation tests” standard. Based on the conditions described in the standard, a small-scale low-budget reactor system were prepared. The temperature during the holding time was controlled with water bath and the gas production was determined with fluid displacement method. A peristaltic pump was used for the recirculation of the gas to mix the base material. Furthermore, the temperatures of the environment, the water baths and the inside of each reactor was automatically registered on a data collector.
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While combustion is the most widespread energy production solution, gasification can produce secondary raw materials for chemical processes as methanol production. However, controlling the process of different stages of gasification as... more
While combustion is the most widespread energy production solution, gasification can produce secondary raw materials for chemical processes as methanol production. However, controlling the process of different stages of gasification as pyrolysis can be challenging if the goal is to produce a synthesis gas with a specific requisite composition. The main objective of our research is to separate the low temperature and high temperature pyrolysis and gain additional control over the whole process. The prospects of this setup have been investigated detailing the gasifier setup and the results of experiments.
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This paper presents the basic research of a pyrolysis plant based in West-Hungary. We studied the pyrolysis of organic fraction and RDF (Refuse Derived Fuel) from MSW (Municipal Solid Waste) in laboratory conditions. Our primary goal was... more
This paper presents the basic research of a pyrolysis plant based in West-Hungary. We studied the pyrolysis of organic fraction and RDF (Refuse Derived Fuel) from MSW (Municipal Solid Waste) in laboratory conditions. Our primary goal was to produce highest conversion rate to synthesis gas from the starting material. The starting material and the process parameters are the two main factors that have a major impact on the quality and quantity the final product (synthesis gas). The quantity and composition of the product (synthesis gas) and residues (slag, tar, oil) have also been investigated.
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The result of the anaerobic degradation of organic material is a renewable energy source, called biogas. Due to its high methane content, biogas is primarily used for energy production. A beneficial method for energy production is... more
The result of the anaerobic degradation of organic material is a renewable energy source, called biogas. Due to its high methane content, biogas is primarily used for energy production. A beneficial method for energy production is cogeneration. Thus, heat and electricity can be produced at the same time. Sheep manure was used for biogas production in lab-scale experiments, using various reactor temperatures with and without the addition of inoculum. The recorded gas yield and gas composition was used to estimate the replaceable natural gas quantity. Furthermore, the necessary gas engine performance was also calculated.
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The aim of this paper is to demonstrate the utilizability of canteen waste as a feedstock for thermochemical processes. For this purpose, a lab-scale experimental reactor has been assembled, in which synthesis gas with 30-45% carbon... more
The aim of this paper is to demonstrate the utilizability of canteen waste as a feedstock for thermochemical processes. For this purpose, a lab-scale experimental reactor has been assembled, in which synthesis gas with 30-45% carbon monoxide-content and 45-53% hydrogen content was repeatedly obtained by pyrolysis. Since considerable amounts of carbon was also produced from the process, the next step of research would involve the transformation of the carbon-rich slags into gas phase.
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The waste material produced in lead-free wave soldering is melted, skimmed and cast into anodes. Anode slime, the by-product of electrorefining in hydrochloric solutions is collected and the basically undissolved silver and copper... more
The waste material produced in lead-free wave soldering is melted, skimmed and cast into anodes. Anode slime, the by-product of electrorefining in hydrochloric solutions is collected and the basically undissolved silver and copper constituents are removed by selective leaching. The first step is the elimination of metallic tin using HCl of high concentration and temperature, followed by the leaching of the nobler metallic components in HNO3 under similar conditions. Kinetic study on the leaching behavior of the raw anode slime in both media has shown the optimum conditions. The metallic tin content of the anode slime can be dissolved virtually completely in 10 M HCl at the highest possible temperature of 85 °C, however it takes about 3 hours. On the other hand, silver can be o quickly dissolved in about 15 minutes by applying approx. 50% HNO3 at 90 °C. Combination of the two steps in this order can result in an efficient recycling of the slime by producing relatively pure SnCl2 and AgNO3 solutions, respectively. The tin content can be recycled conveniently to the tin electrolysis and the silver containing solution can be used for recovering silver by electrowinning or precipitation.