The sorption-induced porosity and permeability alteration of coal beds as pore pressure and in-situ stress are varied can be couched within the frameworks of ‘open thermodynamic system' and ‘open-system geomechanics' (OSG). Production from coal bed methane (CBM) reservoir changes not only the fluid mass (gas and water) but also solid mass as a result of methane desorption from rock matrix. The ...

Prior research has suggeste d that the source of respirable silica dust in underground coal mines is typically the immediate top or bottom lithology adjacent to the mined seam, not mineral matter bound within the mined coal bed. Geochemical analyses were applied in an effort to identify the specific source rock of respirable quartz dust in coal mines. The analyses also demonstrate the compositi...

Clean hydrogen is the major energy carrier for power production. The conversion of CO to CO2 and zero emission during hydrogen energy production causes high capital cost. It is a matter of prestige to optimize the process in order to make zero emission and cost effective production of clean hydrogen energy and electric power. In this era, coal gasification is th...

In this study, effect of biomass share on co-combustion of coal and biomass in a circulating fluidized bed is investigated by previously developed model. SO2 and NOx emission predictions of the model are compared with test results obtained from the laboratory-scale 30 kW (thermal) atmospheric test unit of 0.86 m i.d. and 7 m tall riser data published in the literature. Simulation results show t...

Four types of biomass (chicken waste, wood pellets, coffee residue, and tobacco stalks) were cofired at 30 wt % with a U.S. sub-bituminous coal (Powder River Basin Coal) in a laboratory-scale fluidized bed combustor. A cyclone, followed by a quartz filter, was used for fly ash removal during tests. The temperatures of the cyclone and filter were controlled at 250 and 150 degrees C, respectively...

The combustion of coal in power plants generates solids (e-g., fly ash, bottom ash) and flue gas (e.g., SOX, C02). New Clean Air Act mandated reduction of SOX emissions from coal burning power plants. As a result, a variety of Clean Coal Technologies (CCT) are implemented to comply with these amendments. However, most of the CCT processes transfer environmentally sensitive elements (e.g., As, C...

The influence of fluidized bed combustion (FBC) temperature and coal rank on polycyclic aromatic hydrocarbon (PAH) emissions was assessed. A low-rank coal and a high-rank coal were burnt in a fluidized bed reactor (FBR) on a laboratory scale. An outlet gas sample was passed through a capture system provided with three traps: nylon titer, Teflon filter and XAD-2 resin. The PAH captured were anal...

Solid samples, either of realistic waste model or coal, and spiked with Cd, Pb or Zn, were burned in an electrically-heated fluid bed reactor coupled to a customized ICP spectrometer, for on-line analysis of vaporized metals. For waste samples, a single kinetic law (whatever the metal), predicting the vaporization characteristic time and the time course of the metal concentration in the solid, ...

Coal classification schemes have been developed over many years from studies of the physical and chemical properties of coals as a method of dividing coals into various categories according to their behaviour during carbonisation and combustion. Although there is no universally accepted scheme, most coal classification schemes are based on two main types of parameters:a)volatile matter, and b)c...