Effects of n-Butanol Additions on Combustion and Emission Characteristics of HTL and Diesel blends 2020-01-0393
Biocrude diesel converted from wet biowaste via hydrothermal liquefaction (HTL) is drawing increased attention in recent years due to its wide range of raw materials (algae, swine manure, and food processing waste). However, from the previous experiments done in a constant volume chamber, it was observed that the presence of 20% of HTL in the blend produced as much soot as pure diesel at the ambient oxygen ratio of 21%, and even more soot at low oxygen ratios. It was also observed that n-butanol additions could reduce the soot emissions of diesel significantly under all tested conditions. In this work, the spray and combustion characteristics of HTL and diesel blends with n-butanol added were investigated in a constant volume chamber. The ambient temperature and oxygen ranged from 800 to 1200 K and 13% to 21%, respectively, covering both conventional and low-temperature combustion (LTC) regimes. Time-resolved images of the spray and natural flame luminosity (an indicator of soot) were captured by a high-speed camera coupled with a copper vapor laser beam. The experiments revealed that n-butanol additions could reduce the soot emission of HTL blends but would retard the combustion phasing under LTC conditions with high EGR.
Ziming Yang, Timothy Lee, Chia-Fon Lee
Beijing Institute of Technology, University of Illinois