Abstract
Landfill gas with high methane (CH4) content is a promising renewa-ble energy source. However, the low calorific value landfill gas (LCV LFG) cannot be used for applications and needs to be flared or vented into the atmos-phere. It is a waste of energy and also creates environmental issues as CH4 is a potent greenhouse gas. In this research study, the potential of using hydrogen-enriched LCV LFG for heating applications has been investigated.
Combustion performance of various blends of LCV LFG and hydrogen has been first investigated numerically using Ansys Chemkin-Pro and Fluent with GRI-Mech 3.0 reaction mechanism. The laminar burning velocity (LBV) and the heat release rate (HHR) of the fuel mixtures increased with the increment of the hydrogen fraction added and the initial temperature. The maximum LBV was observed with a slightly rich mixture (φ ~ 1.1). The initial pressure shows a negative effect on LBV while it is affected positively on HHR. The investiga-tions showed that the LFG with 30 vol% CH4 enriched with 30 vol% hydrogen has comparable performance to high calorific value LFG in terms of LBV and HHR. However, analysis showed that the impinging flame heat transfer rate is comparatively low.
Experimental investigations on combustion performance were conducted with the use of a Bunsen like burner operating at ambient conditions. Flame stability maps were developed to identify the feasible stable operation range for different blends of fuel with equivalence ratio ranging from φ = 0.7 – 1.4 and for Reyn-olds numbers Re = 800 – 1200. Stable flames can be obtained when the LCV landfill gas is enriched with 30 vol% or more hydrogen and for rich mixtures. The numerical and experimental investigations show that there is a potential for using hydrogen-enriched LCV landfill gas for heating applications with the use of suitably designed combustion systems operating at high initial temperatures and moderately high pressures.
Combustion performance of various blends of LCV LFG and hydrogen has been first investigated numerically using Ansys Chemkin-Pro and Fluent with GRI-Mech 3.0 reaction mechanism. The laminar burning velocity (LBV) and the heat release rate (HHR) of the fuel mixtures increased with the increment of the hydrogen fraction added and the initial temperature. The maximum LBV was observed with a slightly rich mixture (φ ~ 1.1). The initial pressure shows a negative effect on LBV while it is affected positively on HHR. The investiga-tions showed that the LFG with 30 vol% CH4 enriched with 30 vol% hydrogen has comparable performance to high calorific value LFG in terms of LBV and HHR. However, analysis showed that the impinging flame heat transfer rate is comparatively low.
Experimental investigations on combustion performance were conducted with the use of a Bunsen like burner operating at ambient conditions. Flame stability maps were developed to identify the feasible stable operation range for different blends of fuel with equivalence ratio ranging from φ = 0.7 – 1.4 and for Reyn-olds numbers Re = 800 – 1200. Stable flames can be obtained when the LCV landfill gas is enriched with 30 vol% or more hydrogen and for rich mixtures. The numerical and experimental investigations show that there is a potential for using hydrogen-enriched LCV landfill gas for heating applications with the use of suitably designed combustion systems operating at high initial temperatures and moderately high pressures.
| Original language | English |
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| Publication status | Published - Aug 2024 |
| Event | 11th International Conference on Energy Engineering and Environmental Engineering (ICEEEE 2024) - Xiamen, China Duration: 17 Aug 2024 → 18 Aug 2024 |
Conference
| Conference | 11th International Conference on Energy Engineering and Environmental Engineering (ICEEEE 2024) |
|---|---|
| Country/Territory | China |
| City | Xiamen |
| Period | 17/08/24 → 18/08/24 |
Keywords
- Landfill gas, Alternative energy, Hydrogen-enriched fuel