(395f) Optimal Bio-Refinery Configuration Using Economic Metrics and Environmental Impacts Considering Supply, Demand and Process Uncertainties

Optimal Bio-refinery Configuration using Economic Metrics and
Environmental Impacts Considering Supply, Demand and Process Uncertainties

Abhay Athaley, Yue Zhang and Marianthi Ierapetritou

Department of
Chemical and Biochemical Engineering, Rutgers - The State University of New
Jersey

This work principally concentrates on a multi-objective
optimization approach for the integrated design of bio-refineries that deals
with uncertainties in raw material supply, product demand and process
parameters. The idea of bio-refinery has been proposed to combine the use of
different  technologies to produce multiple products including fuels and
chemicals from biomass. The success of bio-refinery is highly dependent on the
flexibility to produce not only high volume low cost fuels but also to produce
low volume high cost chemicals^[1].  Different simulation
based approaches and mathematical programming models have been proposed in the
literature for the optimal synthesis and design of complex bio-refineries. However
the consideration of uncertainties in the supply of raw materials, production
processing alternative technologies, and demand of products results in  economic
losses and increased emissions^[2].

In our previous work, we investigated a novel
hydrolysis process^[3] for the production of
sugars and the subsequent production of different chemicals and fuels. We
considered the production of p-Xylene^[4], butadiene, jet fuel
and surfactants and carried out economic analysis to calculate the minimum
selling price of the produced chemicals as well as performed life cycle
analysis to analyze carbon emissions and water consumption^[4]. In our present work,
we design an optimal configuration for the production of multiple high value
chemicals and fuels taking into consideration fluctuations in demand and supply
of biomass resources and optimizing both economic and environmental metrics.

This work uses an optimization approach to
design and determine an optimum configuration of a bio-refinery considering various
biomass resources to produce different fuels, chemicals and energy via alternative
production routes. The detailed flowsheet is first developed for production of
p-Xylene, ethanol, surfactants, butadiene, jet fuels and energy via both
enzymatic and thermochemical production pathways from a variety of different
sources of biomass feedtstock using Aspen plus. After this step an economic
analysis is performed to calculate the minimum selling price of each product.
Life cycle analysis is also performed using SimaPro® to
compute carbon emission and water consumption of each process. Multi-objective
optimization is carried out to generate a pareto curve identifying optimal
solutions for maximizing profit and minimizing carbon dioxide generation and
water consumption. Finally, robust optimization approach is developed to
determine the optimum configuration and capacity with consideration to biomass
supply, product demand and process uncertainties.

References:

1.            Lin,
Z.J., V. Nikolakis, and M. Ierapetritou, Alternative Approaches for p-Xylene
Production from Starch: Techno-Economic Analysis. Industrial &
Engineering Chemistry Research, 2014. 53(26): p. 10688-10699.

2.            Sy,
C.L., et al., Multi-objective target oriented robust optimization for the
design of an integrated biorefinery. Journal of Cleaner Production, 2018. 170:
p. 496-509.

3.            Sadula,
S., et al., Process Intensification for Cellulosic Biorefineries.
Chemsuschem, 2017. 10(12): p. 2566-2572.

4.            Athaley,
A., et al., Techno-Economic and Life Cycle Analysis of Different Types of
Hydrolysis Process for the Production of p-Xylene. In review, 2018.