Date of this Version
ACS Sustainable Chem. Eng. 2017, 5, pp. 8804−8814, DOI: 10.1021/acssuschemeng.7b01609.
Horse manure, the improper disposal of which, imposes considerable environmental costs, constitutes an apt feedstock for conversion to renewable fuels and chemicals when tail gas reactive pyrolysis (TGRP) is employed. TGRP is a modification of fast pyrolysis that recycles its noncondensable gases and produces a bio-oil low in oxygen concentration and rich in naphthalene. Herein, we evaluate the coproduction of phenol as a value-added renewable chemical, alongside jet-range fuels within distributed TGRP systems using techno-economic analysis and life cycle assessment. We investigate the metrics global warming potential (GWP), cumulative exergy demand (CExD), and cost for the conversion of 200 dry metric tons per day of horse manure to bio-oil and its subsequent upgrade to hydrocarbon fuel and phenolic chemicals. Assigning credits for the offset of the coproducts, the net GWP and CExD of TGRP jet fuel are 10 g of CO2 eq and 0.4 MJ per passenger kilometer distance traveled, respectively. These values are considerably lower than the GWP and CExD of petroleum-based aviation fuel. The minimum fuel selling price of the TGRP jet fuel ($1.35−$1.80 L−1) is estimated to be much greater than that of petroleum-based aviation fuel ($0.42 L−1), except under optimized fuel conversion and coproduct market conditions ($0.53−$0.79 L−1) when including a market price for carbon.