Hydrogen energy share improvement along with NOx (oxides of nitrogen) emission reduction in a hydrogen dual-fuel compression ignition engine using water injection

• Published in: Energy conversion and management 2014-07, Vol.83, p.249-259
• Main Authors: Chintala, V., Subramanian, K.A.
• Format: Article
• Language: English
• Subjects: Applied sciences; Crude oil, natural gas and petroleum products; Crude oil, natural gas, oil shales producing equipements and methods; Dual-fuel engine; Energy; Energy share; Enhanced oil recovery methods; Exact sciences and technology; Fuels; Hydrogen; NOx emission; Petroleum products, gas and fuels. Motor fuels, lubricants and asphalts; Prospecting and production of crude oil, natural gas, oil shales and tar sands; Specific water consumption
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2014.03.075

•H2 energy share increased from 20% without water to 39% with SWC 270g/kWh.•Specific water consumption (SWC) 200g/kWh was selected as the optimum quantity.•NOx decreased about 24% with the optimum water quantity at 20% H2 energy share.•At 20% H2 share, energy efficiency decreased about 5.5% with the optimum water.•HC, CO and smoke emissions increased 38%, 100% and 69% with optimum water at 20% H2 share. The study aims at enhancement of Hydrogen (H2) energy share and reduction of Oxides of Nitrogen (NOx) emission in a 7.4kW-CI engine at 1500rpm using water injection. The test engine was modified to run under dual-fuel operation with diesel–biodiesel blend (B20) and H2 fuels for different Specific Water Consumption (SWC) of 130, 200, and 270g/kWh. Under conventional H2 dual-fuel mode, energy efficiency and NOx emission increased significantly while Hydrocarbon (HC), Carbon Monoxide (CO) and smoke emissions decreased. The maximum H2 energy share increased from 20% without water to 32%, 36%, and 39% with SWC of 130, 200, and 270g/kWh respectively. However, SWC of 200g/kWh was selected as an optimum water quantity for knock free operation, better performance and lower emissions. At the optimum SWC with 20% H2 energy share, the NOx emission and energy efficiency decreased about 24% and 5.7%, while HC and smoke emissions increased about 38% and 69%. At 20% H2 energy share, the CO emission increased from 0.0g/kWh without water to 1.2g/kWh with the optimum SWC. However, reduction of these HC and CO emissions using oxidation catalysts needs to be studied further. A new methodology for determining heat release rate with consideration of crevice gas was proposed in the study.