scholarly journals The efficiency of the process of coal gasification in the presence of hydrogen

2018 ◽  
Vol 46 ◽  
pp. 00030
Author(s):  
Gracjana Woźniak ◽  
Rafał Longwic ◽  
Kamil Szydło ◽  
Adam Kryłowicz ◽  
Jarosław Kryłowicz ◽  
...  
Keyword(s):  
Fossil Fuels ◽  
Coal Gasification ◽  
Cooling System ◽  
Heating System ◽  
Raw Material ◽  
Hard Coal ◽  
Time Intervals ◽  
Fuel Gas ◽  
Coal Mixture ◽  
Lignite Coal

The results of the research on the process of gasification of coal mixture in a closed system was evaluated in this article. The method presented includes oxygen-free gasification of coal at high pressure and its thermal degradation. Hydrogen is a gasifying factor. Gas containing, among others, methane, carbon dioxide, carbon monoxide, hydrogen is obtained as a result of reaction. Fossil coal as a chemical and energetic raw material is very significant in the process of demand for energy. Due to more and more difficult access to petroleum and natural gas, as well as growing prices, fossil fuels are becoming economically attractive. However, the works on more effective and environmentally friendly methods of energetic use of coal - including its gassing - should be continued. The use of hydrogen during coal gasification allows to get emission-free fuel gas, having better energetic properties than primal raw material.The laboratory site was built and consisted of: 4,5dm3 reactor with a heating system, system of supply reactor with hydrogen and rinsing with argon and cooling system. The results of hydrogasification of coal with specific parameters, for selected time intervals were presented in this article. The efficiency of hydrogasification depending on the type of applied coal was assessed. Powdered charcoal, meeting the norm of German Committee for Standardization DIN EN1860 2 with a number 3H020, hard coal and lignite coal, as well as their mixtures were applied during the research.

Hybrid Technology of Hard Coal Mining from Seams Located at Great Depths

2014 ◽  
Vol 59 (3) ◽  
pp. 575-590 ◽  
Author(s):  
Piotr Czaja ◽  
Paweł Kamiński ◽  
Jerzy Klich ◽  
Antoni Tajduś
Keyword(s):  
Coal Mining ◽  
Fossil Fuels ◽  
Coal Gasification ◽  
Economic Effect ◽  
Balance Sheet ◽  
Value Added ◽  
Coal Extraction ◽  
Innovative Technology ◽  
Hard Coal ◽  
Underground Coal Gasification

Abstract Learning to control fire changed the life of man considerably. Learning to convert the energy derived from combustion of coal or hydrocarbons into another type of energy, such as steam pressure or electricity, has put him on the path of scientific and technological revolution, stimulating dynamic development. Since the dawn of time, fossil fuels have been serving as the mankind’s natural reservoir of energy in an increasingly great capacity. A completely incomprehensible refusal to use fossil fuels causes some local populations, who do not possess a comprehensive knowledge of the subject, to protest and even generate social conflicts as an expression of their dislike for the extraction of minerals. Our times are marked by the search for more efficient ways of utilizing fossil fuels by introducing non-conventional technologies of exploiting conventional energy sources. During apartheid, South Africa demonstrated that cheap coal can easily satisfy total demand for liquid and gaseous fuels. In consideration of current high prices of hydrocarbon media (oil and gas), gasification or liquefaction of coal seems to be the innovative technology convergent with contemporary expectations of both energy producers as well as environmentalists. Known mainly from literature reports, underground coal gasification technologies can be brought down to two basic methods: - shaftless method - drilling, in which the gasified seam is uncovered using boreholes drilled from the surface, - shaft method, in which the existing infrastructure of underground mines is used to uncover the seams. This paper presents a hybrid shaft-drilling approach to the acquisition of primary energy carriers (methane and syngas) from coal seams located at great depths. A major advantage of this method is the fact that the use of conventional coal mining technology requires the seams located at great depths to be placed on the off-balance sheet, while the hybrid method of underground gasification enables them to become a source of additional energy for the economy. It should be noted, however, that the shaft-drilling method cannot be considered as an alternative to conventional methods of coal extraction, but rather as a complementary and cheaper way of utilizing resources located almost beyond the technical capabilities of conventional extraction methods due to the associated natural hazards and high costs of combating them. This article presents a completely different approach to the issue of underground coal gasification. Repurposing of the already fully depreciated mining infrastructure for the gasification process may result in a large value added of synthesis gas production and very positive economic effect.

scholarly journals Pengolahan Daun Tembakau dan Dampaknya Terhadap Lingkungan

2016 ◽  
Vol 3 (2) ◽  
pp. 80
Author(s):  
Samsuri Tirtosastro ◽  
A.S. Murdiyati
Keyword(s):  
Coal Gasification ◽  
Production Systems ◽  
Agricultural Waste ◽  
Hazardous Materials ◽  
Heating System ◽  
Raw Material ◽  
Liquefied Petroleum Gas ◽  
Gradual Process ◽  
Acti Vity ◽  
Tobacco Specific Nitrosamines

<p>Tembakau merupakan bahan baku utama industri hasil tembakau seperti rokok keretek, cerutu, tembakau iris, dan lain-lain. Sebelum digunakan, daun tembakau harus melalui proses pengolahan. Pengolahan tembakau pada dasarnya merupakan kegiatan pengeringan, dengan penerapan suhu bertahap atau disebut proses kiu-ring (curing). Dalam proses pengolahan tembakau diperlukan energi, yang selama ini berasal dari panas ma-tahari, udara panas buatan hasil pembakaran kayu, minyak tanah, batu bara, LPG (liquefied petroleum gas), atau limbah pertanian. Penggunaan bahan bakar ini menyebabkan polusi udara, sehingga mencemari ling-kungan dan meracuni pekerja. Tembakau sendiri mengandung bahan berbahaya seperti, debu tembakau, ni-kotin, residu pestisida, TSNA (tobacco spesific nitrosamine), B-a-P (benzo-a-pyrene), dan lain-lain. Petunjuk pengendalian bahan berbahaya dan dampak lingkungan tersebut, selama ini sudah tersedia secara lengkap yang ditetapkan oleh organisasi tembakau dunia Coresta dan diimplementasikan oleh perusahaan-perusaha-an mitra petani. Petani yang sistem produksinya dalam bentuk kemitraan dengan perusahaan-perusahaan tembakau, telah melakukan pengendalian dengan baik. Dampak negatif penggunaan bahan bakar dapat di-tekan dengan sistem pemanasan tidak langsung (flue-curing), sedangkan penggunaan batu bara dilakukan dengan tungku pembakaran gasifikasi. Implementasi selanjutnya, selain diperlukan sistem inspeksi sesuai ketentuan juga perlu didorong terbentuknya kemitraan antara perusahaan tembakau dan petani.</p><p> </p><p>Tobacco leaf is the main raw material of tobacco industries such as cigarette, cigar, slices tobacco, etc. Be-fore being used, tobacco leaves have to go through processing. Tobacco processing is basically a drying acti-vity, with the application of temperature or a gradual process called curing. In the processing of tobacco ener-gy needed, which is derived from the hot sun, hot air made by the burning wood, kerosene, coal, LPG (li-quefied petroleum gas), or agricultural waste. The use of these fuels causes air pollution, thus contaminating the environment and poisoning workers. Tobacco itself contain hazardous materials such as tobacco dust, ni-cotine, pesticide residue, TSNA (tobacco specific nitrosamines), B-a-P (benzo-a-pyrene) and others. In-structions on control of hazardous materials and environmental impact, as long as it is available completely de-termined by the organization of the world tobacco Coresta and implemented by partner company of farmers. Farmer production systems in the form of partnership with tobacco companies, has done well control. The ne-gative impact of fuel use could be reduced by an indirect heating system (flue-curing), while the use of coal gasification is done by burning stove. Subsequent implementation, in addition to the required inspection sys-tem according to the provisions, should also be encouraged such as partnerships between tobacco companies and farmers.</p>

Characteristics of Nanofluids Made from Solgel Synthesized-Al2O3 Nanoparticles Using Citric Acid and PEG as Organic Agent and Bauxite as Raw Material

2018 ◽  
Vol 929 ◽  
pp. 1-9 ◽  
Author(s):  
Dani Gustaman Syarif ◽  
Djoko Hadi Prajitno ◽  
Efrizon Umar
Keyword(s):  
Citric Acid ◽  
Metal Forming ◽  
Cooling System ◽  
Nuclear Reactors ◽  
Reactor Core ◽  
Heating System ◽  
Solar Heating ◽  
Raw Material ◽  
Peg 4000 ◽  
Core Cooling

Nanofluids have great attention in the world due to big potential to replace conventional fluids that have been used in some systems such as automotive, nuclear reactors, solar heating, building heating, and industry. Utilization of indigenous raw material in production of nanoparticles is a key to reach real application of the nanofluids. The aim of this study is to know the effect of combination of organic agent in solgel synthesis on characteristic of Al2O3nanoparticles and nanofluids made of them. In this study, Al2O3nanoparticles have been synthesized from local bauxite using solgel method with citric acid and PEG 4000 as chelating and capping agent. Nanofluids with pH 10 were prepared from the nanoparticles. Raw material of Al (OH)3was extracted from the bauxite. Powder of Al (OH)3was diluted in water, and citric acid and PEG 4000 was added into the solution to form a sol. The sol was heated to form a xerogel, and then calcined at 900°C for 3 hours to get the Al2O3nanoparticles. From the synthesis we got gamma-Al2O3nanoparticles with crystallite size of 4.0-4.6 nm. From the characterization data of the nanofluids it was known that the nanofluids with concentration of Al2O3nanoparticles of 0.025 vol % to 0.1 vol% possessed relatively high zeta potential of-39.2 mV to-40 mV, and good critical heat flux (CHF) enhancement of 13% to 74%. The nanofluids had large potential to be applied as coolant for External Reactor Core Cooling System (ERVCS), ECCS (Emergency Core Cooling System), electronics, automotive, metal forming and solar heating system.

The Heating System of Agricultural Facilities Using Excess Heat Power Transformers

2020 ◽  
Vol 67 (1) ◽  
pp. 42-47
Author(s):  
Anatoliy I. Sopov ◽  
Aleksandr V. Vinogradov
Keyword(s):  
System Design ◽  
Heat Supply ◽  
Cooling System ◽  
Power Transformer ◽  
Electric Heating ◽  
Heating System ◽  
Power Transformers ◽  
Large Power ◽  
Excess Heat ◽  
Power Centers

In power transformers, energy losses in the form of heat are about 2 percent of their rated power, and in transformers of large power centers reach hundreds of kilowatts. Heat is dissipated into the environment and heats the street air. Therefore, there is a need to consume this thermal energy as a source of heat supply to nearby facilities. (Research purpose) To develop methods and means of using excess heat of power transformers with improvement of their cooling system design. (Materials and methods) The authors applied following methods: analysis, synthesis, comparison, monographic, mathematical and others. They analyzed various methods for consuming excess heat from power transformers. They identified suitable heat supply sources among power transformers and potential heat consumers. The authors studied the reasons for the formation of excess heat in power transformers and found ways to conserve this heat to increase the efficiency of its selection. (Results and discussion) The authors developed an improved power transformer cooling system design to combine the functions of voltage transformation and electric heating. They conducted experiments to verify the effectiveness of decisions made. A feasibility study was carried out on the implementation of the developed system using the example of the TMG-1000/10/0.4 power transformer. (Conclusions) The authors got a new way to use the excess heat of power transformers to heat the AIC facilities. It was determined that the improved design of the power transformer and its cooling system using the developed solutions made it possible to maximize the amount of heat taken off without quality loss of voltage transformation.

scholarly journals Renewable Biomass Utilization: A Way Forward to Establish Sustainable Chemical and Processing Industries

2021 ◽  
Vol 3 (1) ◽  
pp. 243-259
Author(s):  
Yadhu N. Guragain ◽  
Praveen V. Vadlani
Keyword(s):  
Fossil Fuels ◽  
Process Intensification ◽  
Raw Material ◽  
Biomass Composition ◽  
Biomass Feedstocks ◽  
Renewable Biomass ◽  
Sustainability Criteria ◽  
Biomass Component ◽  
Biomass Resources ◽  
Multiple Challenges

Lignocellulosic biomass feedstocks are promising alternatives to fossil fuels for meeting raw material needs of processing industries and helping transit from a linear to a circular economy and thereby meet the global sustainability criteria. The sugar platform route in the biochemical conversion process is one of the promising and extensively studied methods, which consists of four major conversion steps: pretreatment, hydrolysis, fermentation, and product purification. Each of these conversion steps has multiple challenges. Among them, the challenges associated with the pretreatment are the most significant for the overall process because this is the most expensive step in the sugar platform route and it significantly affects the efficiency of all subsequent steps on the sustainable valorization of each biomass component. However, the development of a universal pretreatment method to cater to all types of feedstock is nearly impossible due to the substantial variations in compositions and structures of biopolymers among these feedstocks. In this review, we have discussed some promising pretreatment methods, their processing and chemicals requirements, and the effect of biomass composition on deconstruction efficiencies. In addition, the global biomass resources availability and process intensification ideas for the lignocellulosic-based chemical industry have been discussed from a circularity and sustainability standpoint.

Effect Of Equivalent Ratio (ER) On the Flow and Combustion Characteristics in A Typical Underground Coal Gasification (UCG) Cavity

2021 ◽  
Vol 86 (2) ◽  
pp. 28-38
Author(s):  
Arup Kumar Biswas ◽  
Wasu Suksuwan ◽  
Khamphe Phoungthong ◽  
Makatar Wae-hayee
Keyword(s):  
Mass Flow ◽  
Flow Rate ◽  
Gas Flow ◽  
Coal Gasification ◽  
High Efficiency ◽  
Combustion Characteristics ◽  
Raw Material ◽  
Underground Coal Gasification ◽  
Equivalent Ratio ◽  
Rubble Pile

Underground Coal Gasification (UCG) is thought to be the most favourable clean coal technology option from geological-engineering-environmental viewpoint (less polluting and high efficiency) for extracting energy from coal without digging it out or burning it on the surface. UCG process requires only injecting oxidizing agent (O2 or air with steam) as raw material, into the buried coal seam, at an effective ratio which regulates the performance of gasification. This study aims to evaluate the influence of equivalent ratio (ER) on the flow and combustion characteristics in a typical half tear-drop shape of UCG cavity which is generally formed during the UCG process. A flow modeling software, Ansys FLUENT is used to construct a 3-D model and to solve problems in the cavity. The boundary conditions are- (i) a mass-flow-inlet passing oxidizer (in this case, air) into the cavity, (ii) a fuel-inlet where the coal volatiles are originated and (iii) a pressure-outlet for flowing the product Syngas out of the cavity. A steady-state simulation has been run using k-? turbulence model. The mass flow rate of air varied according to an equivalent ratio (ER) of 0.16, 0.33, 0.49 and 0.82, while the fuel flow rate was fixed. The optimal condition of ER has been identified through observing flow and combustion characteristics, which looked apparently stable at ER 0.33. In general, the flow circulation mainly takes place around the ash-rubble pile. A high temperature zone is found at the air-releasing point of the injection pipe into the ash-rubble pile. This study could practically be useful to identify one of the vital controlling factors of gasification performance (i.e., ER impact on product gas flow characteristics) which might become a cost-effective solution in advance of commencement of any physical operation.

scholarly journals Preliminary determination of the suitability of slags resulting from coal gasification as a pozzolanic raw material / Wstępne Określenie Przydatności Żużli Ze Zgazowania Węgla Jako Surowca Pucolanowego

2012 ◽  
Vol 28 (4) ◽  
pp. 5-14 ◽  
Author(s):  
Maciej Mazurkiewicz ◽  
Ewelina Tkaczewska ◽  
Radosław Pomykała ◽  
Alicja Uliasz-Bocheńczyk
Keyword(s):  
Coal Gasification ◽  
Raw Material ◽  
Preliminary Determination

Streszczenie Wymagania dotyczące ochrony środowiska, takie jak: ograniczenie emisji CO2, NOx i SO2 spowodowały coraz większe zainteresowanie nowymi technologiami energetycznego wykorzystania węgla. Jednąz testowanych i promowanych obecnie technologii jest zgazowanie węgla. Jednak, jak każda technologia produkcji energii wykorzystująca węgiel, powoduje ona powstawanie odpadów: popiołów lotnych i żużli. Ze względu na niewielką ilość instalacji zgazowania węgla funkcjonujących obecnie w świecie, odpady te sąwniewielkim stopniupoznane, dlatego też przed podjęciem decyzji o wprowadzaniu technologii zgazowania węgla, powinno się opracować technologię utylizacji powstających w niej odpadów. Najlepszym rozwiązaniem będzie oczywiście opraco­wanie kierunku ich gospodarczego wykorzystania. Jedną z możliwości rozpatrywanych dla gospodarczego wykorzystania żużli ze zgazowania jest zastosowanie ich jako składnika spoiw mineralnych o charakterze pucolanowym. W artykule przedstawiono wyniki badań aktywności pucolanowej dwóch żużli: żużla ze zgazowania węgla z instalacji energetycznego zgazowania oraz podziemnego zgazowania. Ze względu na skład chemiczny żużel MI można zaklasyfikować jako żużel zasadowy o składzie chemicznym zbliżonym do krzemionkowego po­piołu lotnego ze spalania węgla kamiennego. Z kolei żużel BA, z powodu czteroktrotnie wyższej zawartości tlenku wapnia, należy do grupy żużli słabozasadowych. Podstawowym i jedynym składnikiem mineralnym żużla MI jest faza szklista. W żużlu BA, obok fazy szklistej, tworzą się również fazy krystaliczne, a mianowicie: mullit 3 AI2O3 · 2 SiO2, kwarc p-SiO2-, anortyt Ca(Al2Si2O8), gehlenit Ca2Al[(Si,Al)2O7], wollastonit Ca3[Si3O9], 2CaO · SiO2 i 4 CaO • Al2O3 • Fe2O3. W wyniku badań stwierdzono, że żużel BA wykazuje większe wartości wskaźnika aktywności pucolanowej (75,1% po 90 dniach) od żużla MI (69,9% po 90 dniach). Niestety, wstępne badania pozwalają stwierdzić, że żużle te charakteryzują się zbyt niską aktywnością pucolanową i nie mogą być traktowane jako materiał pucolanowy w technologii produkcji cementu i betonu.

scholarly journals RAPE SEED OIL TETRAHYDROFURFURYLESTERS

2015 ◽  
Vol 1 ◽  
pp. 46
Author(s):  
K. Malins ◽  
V. Kampars ◽  
R. Kampare ◽  
T. Rusakova
Keyword(s):  
Rapeseed Oil ◽  
Fossil Fuels ◽  
Raw Materials ◽  
Methyl Esters ◽  
Cetane Number ◽  
Food Prices ◽  
Raw Material ◽  
Biodiesel Production ◽  
Cold Filter Plugging Point ◽  
Mineral Oils

The transesterification of vegetable oil using various kinds of alcohols is a simple and efficient renewable fuel synthesis technique. Products obtained by modifying natural triglycerides in transesterification reaction substitute fossil fuels and mineral oils. Currently the most significant is the biodiesel, a mixture of fatty acid methyl esters, which is obtained in a reaction with methanol, which in turn is obtained from fossil raw materials. In biodiesel production it would be more appropriate to use alcohols which can be obtained from renewable local raw materials. Ethanol rouses interest as a possible reagent, however, its production locally is based on the use of grain and therefore competes with food production so it would implicitly cause increase in food prices. Another raw material option is alcohols that can be obtained from furfurole. Furfurole is obtained in dehydration process from pentose sugars which can be extracted from crop straw, husk and other residues of agricultural production. From furfurole the tetrahydrofurfuryl alcohol (THFA), a raw material for biodiesel, can be produced. By transesterifying rapeseed oil with THFA it would be possible to obtain completely renewable biodiesel with properties very close to diesel [2-4]. With the purpose of developing the synthesis of such fuel, in this work a three-stage synthesis of rapeseed oil tetrahydrofurfurylesters (ROTHFE) in sulphuric acid presence has been performed, achieving product with purity over 98%. The most important qualitative factors of ROTHFE have been determined - cold filter plugging point, cetane number, water content, Iodine value, phosphorus content, density, viscosity and oxidative stability.

scholarly journals Ethanol-Based Biodiesel from Waste Vegetable Oil

2007 ◽  
Vol 7 (1 & 2) ◽  
pp. 83
Author(s):  
Mary Grace M. Oliveros ◽  
Amiliza B. Baiting ◽  
Menchie G. Lumain ◽  
Maria Theresa I. Cabaraban
Keyword(s):  
Vegetable Oil ◽  
Fast Food ◽  
Fossil Fuels ◽  
Material Balance ◽  
Raw Material ◽  
Biodiesel Production ◽  
Exhaust Emission ◽  
Waste Vegetable Oil ◽  
Power Testing ◽  
Technological Analysis

Waste vegetable oil, mainly coming from frying residues, can be used as raw material to obtain a diesel fuel (biodiesel). Biodiesel, a nontoxic, biodegradable, diesel-like fuel, is an important energy alternative capable of decreasing environmental problems caused by the consumption of fossil fuels. The utilization of waste vegetable oils as raw material in biodiesel production was studied. Research was undertaken to establish the availability of used vegetable oil to supply a biodiesel process. It is intended that this work forms an academic study combined with an environmental and technological analysis of the merits of biodiesel as a sustainable fuel. Laboratory experimentation investigated the possibility of using waste vegetable oil from the local fast food chains, and potassium hydroxide as catalyst for the transesterification process. The cleaned waste vegetable oil undergoes transesterification for 4 hours, after which, the biodiesel is separated from the glycerin by gravity. Washing is necessary to remove residual catalyst or soap. Overall material balance for the process gives: 1 kg Waste Vegetable oil + 0.18 kg EtOH + 0.01 kg KOH → 0.74 kg Biodiesel + 0.44 kg Glycerin The biodiesel, in pure form (B100) and in 50% proportion (B50) with petroleum diesel, was run in an essentially unmodified Toyota 2C diesel engine. Smoke density (opacity) and CO exhaust emission both decreased with B50. However, Nox increased with B50. Fuel consumption during engine power testing is significantly greater using the biodiesel, but is also significantly reduced with B50.

scholarly journals Simulation of a severe accident at a typical PWR due to break of a hot leg ECCS injection line using MELCOR code.

2019 ◽  
Vol 7 (2B) ◽  
Author(s):  
Seung Min Lee ◽  
Nelbia Da Silva Lapa ◽  
Gaianê Sabundjian
Keyword(s):  
Cooling System ◽  
Severe Accident ◽  
Time Intervals ◽  
Severe Accidents ◽  
Independent Analysis ◽  
Accident Management ◽  
Injection Line ◽  
Core Cooling ◽  
Control Volumes ◽  
Physical Phenomena

The aim of this work was to simulate a severe accident at a typical PWR, initiated with a break in Emergency Core Cooling System line of a hot leg, using the MELCOR code. The model of this typical PWR was elaborated by the Global Research for Safety and provided to the CNEN for independent analysis of the severe accidents at Angra 2, which is similar to this typical PWR. Although both of them are not identical, the results obtained of that typical PWR may be valuable because of the lack of officially published simulation of severe accident at Angra 2. Relevant parameters such as pressure, temperature and water level in various control volumes, after the break at the hot leg, were calculated as well as degree of core degradation and hydrogen production within the containment. The result obtained in this work could be considered satisfactory in the sense that the physical phenomena reproduced by the simulation were in general very reasonable, and most of the events occurred within acceptable time intervals. However, the uncertainty analysis was not carried out in this work. Furthermore, this scenario could be used as a base for the study of the effectiveness of some preventive or/and mitigating measures of Severe Accident Management by implementing each measure in this model.

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