Methanol + Hydrogen - A Prospective Alternate Fuel for Cleaner Offshore Power Generation

Abstract

Abstract This paper analyzes the benefits of employing reciprocating engines to power offshore oil and gas (O&G) loads using methanol as fuel instead of (or mixing with) diesel that has been used conventionally. The study is carried out on a methanol-based single-cylinder, 50-liter, heavy-duty reciprocating engine for two test cases of power (30 kW and 111 kW) at different boost pressure and injection timing. In this investigation, 1-dimensional modeling and analysis using Ricardo Wave software was performed. Then, the effect of adding small amounts (<10%) of hydrogen into the engine in terms of performance improvement and emissions’ reduction is explored. Moreover, engine performance, indicated thermal efficiency, and CO/NOx emissions are compared for different boost pressure values at varied injection timing and constant power. The tests are carried out by modeling multiple use cases and comparing them, including (i) direct injection of methanol, and (ii) direct injection of methanol with port injection of hydrogen by spark ignition method. The addition of hydrogen with methanol results in a significant reduction in emissions and increase in the indicated thermal efficiency. Moreover, advancing the injection timing and increasing the boost pressure decrease the CO/NOx emissions, and also improve the indicated thermal efficiency. This paper presents these analyses in detail for multiple test conditions.