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Simulation studies on the influence of other combustible gases on the characteristics of methane explosions at constant volume and high temperature

Luo Zhenmin, Liu Litao, Gao Shuaishuai, Wang Tao, Su Bin, Wang Lei, Yang Yong, Li Xiufang

Archives of Mining Sciences

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2021

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Vol. 66, no. 2

279--295

EN

Gas explosions are major disasters in coal mining, and they typically cause a large number of deaths, injuries and property losses. An appropriate understanding of the effects of combustible gases on the characteristics of methane explosions is essential to prevent and control methane explosions. FLACS software was used to simulate an explosion of a mixture of CH4 and combustible gases (C2H4, C2H6, H2, and CO) at various mixing concentrations and different temperatures (25, 60, 100, 140 and 180℃). After adding combustible gases to methane at a constant volume and atmospheric pressure, the adiabatic flame temperature linearly increases as the initial temperature increases. Under stoichiometric conditions (9.5% CH4-air mixture), the addition of C2H4 and C2H6 has a greater effect on the adiabatic flame temperature of methane than H2 and CO at different initial temperatures. Under the fuel-lean CH4-air mixture (7% CH4-air mixture) and fuel-rich mixture (11% CH4-air mixture), the addition of H2 and CO has a greater effect on the adiabatic flame temperature of methane. In contrast, the addition of combustible gases negatively affected the maximum explosion pressure of the CH4-air mixture, exhibiting a linearly decreasing trend with increasing initial temperature. As the volume fraction of the mixed gas increases, the adiabatic flame temperature and maximum explosion pressure of the stoichiometric conditions increase. In contrast, under the fuel-rich mixture, the combustible gas slightly lowered the adiabatic flame temperature and the maximum explosion pressure. When the initial temperature was 140℃, the fuel consumption time was approximately 8-10 ms earlier than that at the initial temperature of 25℃. When the volume fraction of the combustible gas was 2.0%, the consumption time of fuel reduced by approximately 10 ms compared with that observed when the volume fraction of flammable gas was 0.4%.

2

Podstawowe zasady klasyfikacji stref zagrożenia wybuchem

Kulak Ł.

Promotor BHP

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2016

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nr 11

32--38

PL

Niniejszy artykuł ma na celu przedstawić podstawowe zasady klasyfikacji stref zagrożenia wybuchem dla palnych gazów, par cieczy oraz pyłów. Zapraszamy do lektury.

3

Modelling of the gas combustion process

Baczyńska T., Głowiński J., Hałat A.

Polish Journal of Chemical Technology

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2008

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Vol. 10, nr 1

15-18

EN

This paper reports on a procedure which leads to the assessment of the K(G) values without the need of determining the maximal rate of pressure rise by experiments. A simulation is proposed of the combustion process in its simplest form, i.e. one-dimensional propagation of the flame. Such simulation enables the burning velocity S(u) to be assessed. Knowing the S(u) values for different compositions of the flammable mixture makes it possible to determine the S(u,max) value. Once the correlation between S(u,max) and K(G) has been established, this will enable us to assign an appropriate value of K(G) to that of the maximal burning velocity. An example of such a correlation is given. It refers to flammable mixtures of a comparatively low burning velocity.

4

Przegląd efektów energetycznych i ekologicznych różnych sposobów realizacji gospodarki skojarzonej cieplno-elektrycznej

Ziębik A.

Zeszyty Naukowe. Energetyka / Politechnika Śląska

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2003

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z. 139

347-360

PL

W pracy przestawiono metodykę oraz rezultaty oceny efektów energetycznych i ekologicznych dla różnych przypadków realizacji gospodarki skojarzonej cieplno-elektrycznej w Polsce. Obok elektrociepłowni komunalnych i przemysłowych gospodarka skojarzona jest także realizowana poprzez ucieplownienie bloków energetycznych. Zwrócono uwagę na strukturę cen paliw w Polsce, która hamuje rozwój elektrociepłowni opalanych gazem ziemnym. Tylko elektrociepłownie opalane nietypowymi gazami palnymi (palne gazy technologiczne, gaz z odmetanowania kopalni, gaz ziemny pozasystemowy) są opłacalne. Ustawodawstwo energetyczne, wzorowane na unijnym, sprzyja w zasadzie rozwojowi skojarzonej gospodarki cieplno-elektrycznej w Polsce.

EN

The paper presents a method and the results of assessing the energy and ecological effects in the case of various ways in which CHP are realised in Poland, where hard coal is the dominating primary fuel. Besides district heating and industrial CHP 's heat is produced in co-generation also in power stations adapted to the production of heat. Attention has been drawn to the disadvantageous structure of prices for primary fuels in Poland which hampers the development of CHP's fired with natural gas. Only CHP 's fired with untypical fuel gases (technological fuel gases, mining gas, biogas etc.) ensure profitability. It has been stressed that the Polish legislation complying with that of UE can favour the development of co-generation in Poland.

5

Wytwarzanie gazów palnych i syntezowych przez utylizację odpadów w plazmie

Kotowski W., Marcjasz-Siemiątkowska I.

Gospodarka Paliwami i Energią

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2003

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nr 2

18-22

PL

Scharakteryzowano wariantowe konstrukcje reaktorów do wytwarzania plazmy termicznej oraz plazmotronów. Opisano różne procesy utylizacji odpadów do neutralnych (obojętnych dla środowiska) odpadów stałych oraz do gazów palnych, z których większość nadaje się do syntezy metanolu.

EN

Alternative designs were characterised for the reactors capable of generating thermal plasma and for plasmatrones. Various processes were then considered for utilisation of wastes in that equipment. Conversion of wastes would yield neutral (i.e. environmentally friendly) solid wastes and fuel gases; majority of the latter could be further processed in the methanol synthesis.