https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:28040 e coal-fired power plant in New South Wales, Australia, for oxy-fuel conversion using integrated chemical looping air separation (ICLAS) technology and cryogenic air separation unit (CASU). The key objectives of this study are to (i) investigate and compare the detailed integration options for oxy-fuel conversion using ICLAS and CASU and (ii) determine the technical merits of the above integration options and the conditions at which the technologies become economically feasible. The study produced scientific evidence that confirms the viability of the CLAS process from both technical and economic points of view under certain conditions. The detailed technical analysis revealed that ICLAS with natural gas integration is energy-efficient compared to CASU running on parasitic load. This is primarily due to the fact that ICLAS needs less auxiliary power compared to CASU. Despite the fact that ICLAS natural gas integration has resulted in higher efficiencies than CASU running on parasitic load, from a series of detailed economic analyses, it was observed that both ICLAS and CASU may not be viable under the present operating and economic conditions. Nevertheless, from sensitivity analysis, it was concluded that ICLAS can become feasible if economic conditions are improved, e.g., a low natural gas market price (<$3.5/GJ), a high electricity wholesale price (>$59/MWh), and/or a high carbon tax (>$33/tonne).]]> Wed 31 Aug 2022 08:48:11 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:33242 Wed 19 Sep 2018 14:23:23 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:44672 Wed 19 Oct 2022 14:08:30 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:47199 Wed 14 Dec 2022 16:10:00 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:15848 Wed 11 Apr 2018 13:07:52 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:28688 Wed 11 Apr 2018 12:17:45 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:34989 Wed 09 Jun 2021 16:04:03 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30969 −3) on the deflagration of methane in a hybrid form. The work addressed the characteristic of hybrid flame deflagration behaviour including the flame velocity, pressure profile, dynamic and static pressure. Two concentrations of coal dust were introduced to the methane deflagrations, which were 10 g m⁻³ and 30 g m⁻³. The results revealed that the presence of a diluted coal dust of 10 g m⁻³ significantly enhanced the flame travelling distance of a 5% methane concentration, from 12.5 m to 20.5 m. Introducing a 30 g m⁻³ coal dust concentration also enhanced the flame travelling distance of a 5% methane concentration, from 12.5 m to the EDT (End of Detonation Tube, 28.5 m). This enhancement was associated with boosting the flame velocity and the over pressure rise. For a higher methane concentration (i.e., a 7.5% methane concentration), the flame of the methane reached the EDT. Introducing 10 g m⁻³ coal dust to a 7.5% methane explosion increased the flame intensity signal, from 1 V to the maximum reading value (10.2 V), and enhanced the flame velocity at the EDT by about 14 m s⁻¹ and finally, increased the stagnation pressure at the end of the detonation tube from 1.25 bar to 4.6 bar.]]> Wed 04 Sep 2019 10:06:45 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30951 –1 to 359 m·s^–1 and enhanced the flame deflagration velocity from 105 m·s^–1 to 179 m·s^–1.]]> Wed 04 Sep 2019 09:49:11 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:34894 Wed 04 Dec 2019 09:49:10 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:55238 Wed 01 May 2024 15:41:08 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37735 Tue 30 Mar 2021 09:27:52 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:52546 Tue 17 Oct 2023 15:19:51 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:45519 L/D = 66). Subsequently, the explosion behaviour immediately after the ignition of methane-air mixtures and the propagation characteristics of the flame front and pressure wave through the tube are examined, covering a broad range of L/D, that is from 26 to 526, in which the diameter is changed and the length is kept fixed. The results show that the pressure wave propagates significantly faster in narrower tubes and hence decouples from the flame front shortly after ignition, which in turn results in a low overpressure at the flame front. Moreover, abrupt changes in gas properties are observed in narrow tubes with L/D ≥ 132. The peak overpressure increases as the tube diameter increases; however, the local maximum pressure decreases substantially in large tubes when approaching the tube vent but remains almost constant throughout in the narrow tubes. Similarly, the flame propagates faster in narrower tubes. A correlation that estimates the distance the flame propagates in the exponential acceleration stage is proposed as a function of tube size and time. Deviations of less than 7% are obtained when comparing the predicted results using the correlation against the experimental data. The results provide local information that aids the theoretical interpretation of experimental observations and the understanding of the fuel combustion and explosion phenomena in different sized tubes.]]> Tue 14 Nov 2023 14:40:30 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:38189 2 are the most potent of the greenhouse gases (GHGs), and one of the most promising methods of methane abatement is for methane to be captured through thermal decomposition processes. However, this approach introduces a major safety concern related to methane explosions and flame propagation in coal mines. It is vital that all of the safety issues related to this approach are addressed prior to the implementation of GHG emission control. This study investigates the effectiveness of venting in the event of methane explosions. In addition, the study examines the scaling effects by integrating the experimental results from this study with the data from previous explosion experiments carried out in a smaller scale experimental apparatus. The experimental setup consisted of a 1 m³ explosion chamber connected to a 9.7 m long venting duct. The results indicated that the methane explosion pressure significantly decreased in the venting duct, which, in turn, reduced the deflagration index (class of explosion). The venting approach can reduce the explosion pressure by approximately 83%. The data for the flame propagation inside the venting duct demonstrated the presence of flame acceleration and deceleration patterns at approximately one-third (3.2 m), and at the end of the venting duct, these flame accelerations (second explosion) have not been observed when using a 20 L explosion chamber with a similar venting ratio under identical ignition energies and methane concentrations. The flame front velocity reaching the end of the venting duct was measured at approximately 52 m s^–1.]]> Tue 10 Aug 2021 15:46:46 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30952 -3 coal dust concentration boosted the flame travel distance, from 6.5 m to 28.5 m, and increased the over pressure rise profile to 0.135 bar. The over pressure rise (OPR), pressure wave velocity, flame intensity and the flame velocity were significantly boosted along the LSSD in the presence of 10 g m^-3 or 30 g m^-3 coal dust concentrations in the methane flame deflagrations. Finally, the high speed camera showed that the presence of the coal dust enhanced the turbulence in the front flame. Consequently, the pressure wave and flame velocities were both increased when a 10 g m^-3 coal dust concentration coexisted with a 9.5% methane concentration in the deflagration.]]> Tue 04 Jun 2019 13:58:16 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30950 Tue 03 Sep 2019 18:31:06 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30929 Thu 31 Oct 2019 11:47:10 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:32403 -1. The deposition prediction indicates that coal dust particles (50-212 µm) could be deposited in the VAM capture duct within 55 m to 217 m depending on the particles size, particle velocity. MIE tests for three size ranges of coal dust particles were undertaken. Results showed that the MIE of coal dust particles in the 0-74 µm size range, ignited in a range of 100-300 mJ. However, for the coal dust particles in the size range from 74-125 µm and 125-212 µm the MIE measured was in the range of 300-1000 mJ. The ignition coal dust concentration was varied between 150 g.m^-3 to 1500 g.m^-3 for the tests.]]> Thu 31 May 2018 09:12:19 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:32401 -1 at 4.0 m from the ignition source) than inside the vessel (173 bar.s^-1) for 9.5% methane.]]> Thu 31 May 2018 09:12:14 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:32402 Thu 31 May 2018 09:12:07 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:32400 -1 for the range of methane mixtures exploded. The severity of the explosions increased with increasing igniter energy. The maximum pressure rise rate increased from 83 bar.s ^-1 for 1 kJ igniter to 90 bar.s^-1 for 2 kJ igniter, to 155 bar.s^-1 for 5 kJ igniter and to 222 bar.s^-1 for 10 kJ igniter. The severity of the explosions increased with increased coal dust concentration. At 2.5% methane-air mixture, the pressure rise rate increased from 4 bar.s^-1 to 114 bar.s^-1 when the coal dust concentration increased from 50 g.m^-3 to 100 g.m^-3, respectively.]]> Thu 31 May 2018 09:05:09 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37531 Thu 04 Feb 2021 15:19:21 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:34979 Thu 03 Oct 2019 15:06:54 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:9031 Sat 24 Mar 2018 08:39:12 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:12548 Sat 24 Mar 2018 08:16:34 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:17789 Sat 24 Mar 2018 07:57:25 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:19113 Sat 24 Mar 2018 07:55:52 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:19312 600 °C). Proximate analyses indicated near complete devolatilization was apparent at 800 °C for both mines, with thermogravimetric analysis (TGA) revealing that peak devolatilization occurred at 455 °C for Mine A and 467 °C for Mine B. A substantial increase in surface area with increasing pyrolysis temperature was observed for Mine A chailings from 2.7 m²/g at 400 °C to 75.3 mm²/g at 800 °C, because of the presence of microporosity, while Mine B chailings decreased from 2.4 m2/g at 400 °C to 1.2 mm²/g at 800 °C, which was attributed to macroporosity and aggregation of particles. Properties of high-temperature (>600 °C) chailings, namely, surface area, porosity, and pH offer promise for future investigations regarding the application of chailings to soil.]]> Sat 24 Mar 2018 07:51:55 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:20155 Sat 24 Mar 2018 07:51:37 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:20156 Sat 24 Mar 2018 07:51:36 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:20154 Sat 24 Mar 2018 07:51:35 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:20158 Sat 24 Mar 2018 07:51:35 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30286 80%. The MAIT of four different coal dust samples (Australian coal) with particle sizes below 212 µm and dust layer thicknesses of 5, 12 and 15 mm were measured using a dust layer auto ignition temperature apparatus in accordance with the ASTM E2021 standard. It was concluded that the MAIT of the coal dust layer significantly decreases with decreasing particle size. The MAIT for the coal samples with a smaller D50 size were observed to be lower in comparison with samples with a larger D50 size. The dust layer thickness was shown to significantly impact on the MAIT. The MAIT increased proportionally with the increasing thickness of the coal dust layer. The effect of the coal dust moisture content and humidity on the MAIT for compacted dust layers was noticeable, whereas, this effect was less important with loose dust layers. In addition, this work investigated and compared the MAIT for a typical coal dust sample based on the existing ASTM and International Electrotechnical Commission (IEC) standard procedures for ignition of coal dust layers.]]> Sat 24 Mar 2018 07:33:35 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30647 50), and moisture content, impact on the MAIT. For coal dust concentrations less than 1000 g.m⁻³, the MAIT decreases with increasing coal dust concentrations. On the other hand, for low concentrations of 100 to 15 g.m⁻³, the MAIT becomes more reliable for particle size D₅₀ rather than for volatile matters.]]> Sat 24 Mar 2018 07:33:22 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:29996 st) and explosive region of hybrid fuel mixtures present in Ventilation Air Methane (VAM) were investigated. Experiments were carried out according to the ASTM E1226-12 guideline utilising a 20 L spherical shape apparatus specifically designed for this purpose. Results: obtained from this study have shown that the presence of methane significantly affects explosion characteristics of coal dust clouds. Dilute concentrations of methane, 0.75-1.25%, resulted in coal dust clouds OPR increasing from 0.3 bar to 2.2 bar and boosting the K_st value from 10 bar m s^-1 to 25 bar m s^-1. The explosion characteristics were also affected by the ignitors' energy; for instance, for a coal dust cloud concentration of 50 g m^-3 the OPR recorded was 0.09 bar when a 1 kJ chemical ignitor was used, while, 0.75 bar (OPR) was recorded when a 10 kJ chemical ignitor was used.For the first time, new explosion regions were identified for diluted methane-coal dust cloud mixtures when using 1, 5 and 10 kJ ignitors. Finally, the Le-Chatelier mixing rule was modified to predict the lower explosion limit of methane-coal dust cloud hybrid mixtures considering the energy of the ignitors.]]> Sat 24 Mar 2018 07:28:52 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30224 Sat 24 Mar 2018 07:26:33 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30032 Sat 24 Mar 2018 07:24:22 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:23740 2. The key innovation was the use of concrete and demolition waste (CDW) as the source of CO₂ sorbent. A comprehensive series of thermogravimetric analysis (TGA) experiments was carried out over a range of temperatures between 650 and 900 °C and pressures up to 20 atm to benchmark the CO₂ capture efficiency of CDW against conventional lime-based sorbents [e.g., calcined limestone (CL) and hydrated Portland cement (HPC)]. Effects of controlling parameters, such as the Ca/C ratio, steam/carbon (S/C) ratio, steam partial pressure, and total pressure, on the gas yield, gas composition, and CO₂ capture efficiency were thoroughly examined. Experimental results confirmed that CO₂ capture efficiencies as high as 56.4% and high-grade hydrogen production can be achieved when CDW is used as a sorbent. These results combined with the high mechanical strength, durability, and low cost make CDW an attractive sorbent for chemical looping gasification of carbonaceous solid fuels, particularly biomass.]]> Sat 24 Mar 2018 07:16:55 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:24708 Sat 24 Mar 2018 07:11:05 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:52839 Mon 30 Oct 2023 09:41:40 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:54967 Mon 25 Mar 2024 12:11:30 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:46411 Mon 21 Nov 2022 13:51:45 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:37097 Mon 17 Aug 2020 13:30:43 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:42799 Mon 05 Sep 2022 09:08:32 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:34978 3 spherical explosion chamber. The effects of turbulence and explosive powders on explosion parameters such as the deflagration index, maximum explosion pressure and burning velocity were examined. Theoretical calculations were conducted and are presented alongside the experimental data. The study suggests that the presence of turbulence increases the maximum explosion pressure. The values of the deflagration indices and burning velocities were found to be increased by the turbulence. The presence of an explosive powder provides similar effects to turbulence, and the values of the maximum explosion pressure, deflagration index and burning velocities increased with increases of the mass of the explosive powders. The magnitude of the turbulence generated in the explosion chamber was determined theoretically by employing Damköhler’s correlation.]]> Mon 02 Mar 2020 11:49:31 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30930 Mon 01 Jul 2019 10:11:58 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:35160 th demonstration pilot plant CFM–CLC system (the first of its kind in Australia) that is a scaled-up unit of a lab scale 10-kW_th unit is designed, fabricated and commissioned. The hydrodynamics similarities of the two units in terms of pressure drop profile and solids circulation rate are investigated. The results showed that the scaling factor for the operating velocity calculated based on the dimensionless relation of the fluidisation gas velocity ratio and the square root of the fluidised bed height ratio (of the air reactor) is 2.36, which was in good agreement with the measured value of 2.55. The same solids circulation rate (SCR) between the units was achieved using the scaling factor of 2.55 whilst maintaining the ratio of normalised total solids inventory of the system equal 1. It was also demonstrated that as the ratio of normalised total inventory increased from 1 to 1.4, the gas velocity to achieve similar SCR needs to be reduced proportionally (in the unit which inventory was increased). Therefore, a simple method of calculating the required gas velocity for achieving the same SCR for systems with non-equivalent normalised total solids inventory is proposed. The prediction results using this method were compared against the experimental data, with an average deviation of less than 10%. The validity of the proposed prediction method (for other cases of non-equivalent normalised total solids inventory) however requires further investigation.]]> Fri 21 Jun 2019 15:19:57 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:51081 Fri 18 Aug 2023 09:32:00 AEST ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:53226 Fri 17 Nov 2023 11:48:42 AEDT ]]> https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:36779 Fri 03 Jul 2020 17:08:42 AEST ]]>