Energy Analysis of a Small Capacity Si Engine Fueled With Lean Air Gas Mixture

Combined use of coal mine gases for efficient energy generation

“…Results of the several experimental investigations [7,8] confirm that for powering of the internal combustion gas engines is preferable to use the socalled over-stoichiometric flammable mixtures, i.e., those which are characterized by a slightly higher values (1.5 > λ > 1.0) of the air (oxygen) excess ratio. This procedure, by applying the over-stoichiometric air excess (1.5 > λ > 1.0) allows for achieving of higher values of effective energy efficiency of the internal combustion gas engine.…”

“…The gas air-methane mixture with a slightly higher content of methane CH 4 , it means at z M > z M,max can also be ignited (it is also usually a serious mine explosion hazard); however, a combustible mixture by more than stoichiometric participation of methane should not be directly used [7,8] for fueling of different energy plants (e.g., boilers, gas turbines, internal combustion engines).…”

“…The diesel engine will be basically filled out with the gas fuel, but for ignition of the prepared fuel gas-air mixture a specified, minimal amount of the liquid fuel (diesel oil) should be at first additionally injected into the combustion chamber [7,8].…”

“…A different situation is characterized by utilization of the gas from demethanation of coal deposits; the main combustible component methane occurs in relative stoichiometric excess, which means that for the full and complete combustion of this gas an additional amount of oxidant (air, oxygen O 2 ) should be supplied into the combustion chamber [2,9]. In view of the above it was noted, that it is possible to prepare the good gas combustible mixture (mainly in the aspect of the appropriate oxygen excess ratio, λ [7,8]) -by adequate mixing of the ventilation gas stream with the gas stream from demethanation of coal deposits.…”

“…Serious difficulties in this area (e.g. using them as the fuel for internal combustion (IC) engine) occur mainly in relation to the ventilation gas, whereas the gas from demethanation of coal deposits can be used directly as the fuel for IC engines [6][7][8].…”