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To defossilize the current liquid energy backbone a sustainable renewable substitute for fossil crude oil is required. The long–term aim is to increase the co-feed of renewables beyond the current level. However, technical constrains and certain properties limit the conventional biogenic co-feed level to less than 10%. The potential of identifying refinery compatible entry points to directly co-feed bio-based refinery intermediates and further co-process in existing petroleum crude oil refineries is investigated in the current study. The studied pyrolysis bio-oil has been upgraded via mild hydrotreatment (HDT) in order to fulfil specifications and become a “drop-in” biofuel in compatible refinery “location”. The properties of HDT-Bio-oil as well as fossil-based refinery intermediates were compared and five fossil-based refinery intermediates have been concluded as potential candidates for co-processing. The miscibility of the aforementioned renewable and conventional fuels has been investigated. Among all refinery streams, Fluid Catalytic Cracking Light Cycle Oil (FCC LCO) and secondly Light Vacuum Gas Oil (LVGO) have been concluded to be the most promising candidates for co-processing, resembling HDT-Bio-oil’s properties.

Biomass-based fast pyrolysis bio-oil is a low-quality liquid product that is unsuitable for use as transportation fuel, however after a mild upgrading step it can be used as a reliable co-feed in underlying refineries for the production of hybrid transportation fuels. The current study investigates the upgrading of bio-oil to high-quality refinery intermediates via catalytic hydrotreatment, as part of the BioMates project. The bio-oil used in this research was produced via ablative fast pyrolysis of a mixture made from barley and wheat straw at 50 wt.% each. The aim was to examine various operating hydrotreating conditions such as pressure, temperature and H2/oil ratio. For this study, a small pilot hydroprocessing plant of Centre for Research & Technology Hellas (CERTH) was utilized. Three reaction temperatures were investigated (300°, 330° and 360°C), two reaction pressures (580 and 1000 psi) and two H2/oil ratios (3,000 and 5,000 scf). The catalyst employed is a custom-made NiMo/Al2O3 based catalyst that was developed as part of the BioMates project. The results have shown that mild hydrotreating conditions are preferable from a product quality viewpoint and performance of the process. Catalytic hydrotreatment achieved total removal of oxygen and dissolved water from the initial bio-oil feed. The water instead formed a second product phase (40% v/v). Furthermore, the properties of the targeted organic phase product were improved as far as viscosity, density and Total Acid Number (TAN) are concerned. From the evaluation of the three hydrotreating temperatures, it is concluded that higher reaction temperatures favor HDO reactions and decrease the viscosity of the products. Moreover, lower reaction pressures favor catalyst deactivation and Δp creation. Finally, lower H2/oil ratio results in catalyst life reduction. The proposed technology is a very promising pathway for pyrolysis bio-oil upgrading to high-quality refinery intermediates with minimal oxygen and water content.

The current strategic framework for a Resilient Energy Europe, having set ambitious 2020 and 2030 energy and climate targets, calls for energy security, a decarbonized economy and a fully-integrated and competitive European energy market. Toward this direction, the European Industrial Bioenergy Initiative (EIBI), launched under the Strategic Energy Technology (SET) Plan, prioritized pyrolysis technology among the most promising ones. Therefore, international research is being conducted on developing and further validating strategies and innovative technological pathways that will overcome techno-economic limitations associated with the valorisation of pyrolysis bio-oil, as an alternative and renewable transport fuel. In this respect, pyrolysis bio-oil refinery integration appears to be of great perspective. The study is part of BioMates Horizon2020 research and innovation EU project, aspiring in combining innovative 2nd generation biomass conversion technologies for the cost-effective production of reliable bio-based intermediates that can be further upgraded in existing oil refineries as renewable and reliable co-feedstocks. The main premise of this study is to overcome the key technological challenges of co-processing refinery intermediates with the newly developed bio-based intermediates, i.e. hydrotreated pyrolysis bio-oils (BioMates). In this frame, the homogeneity of the two types of feedstocks is initially conducted via a miscibility study, as a pre-screening step of the candidate refinery intermediate for the co- hydroprocessing study that will follow. Among the candidate refinery streams, Light Cycle Oil (LCO), which is the product of the Fluid Catalytic Cracking (FCC) unit, was identified as the most compatible feedstock, which is conventionally subjected to hydrotreatment (HDT) in order to reduce its sulphur levels and to saturate aromatics thus increasing its cetane number. The present study particularly investigates the compatibility of LCO with BioMates towards downstream co-hydroprocessing, intended within existing petroleum crude oil refineries. Co-hydrotreatment of the referenced mixture of BioMates and LCO is furthermore investigated in a continuous hydroprocessing pilot-plant, following a detailed multi-parameter hydrotreatment testing protocol that targets to formulate the optimal operating window (e.g. temperature, H2 partial pressure).

The production of renewable liquid fuels for transport has attracted international research and market interest in line with the ambitious 2020 and 2030 energy and climate targets set by the European Union (EU) policy, considering the increasing global demand for their fossil counterparts and the resulting environmental impact. Toward this direction, the utilization of non-food/feed biomass is promoted, while the most promising bio-chemical and thermo-chemical value chains for biofuels production have been prioritized by the European Industrial Bioenergy Initiative (EIBI), launched under the Strategic Energy Technology (SET) Plan, listing pyrolysis among them. In this frame, the study investigates refinery-compatible entry points to directly co-feed bio-based refinery intermediates and further co-process them in existing petroleum crude oil refineries. The studied pyrolysis bio-oil has been produced via ablative fast pyrolysis and upgraded via mild hydrotreatment (HDT) in order to fulfill refineries’ specifications and become a “drop-in” biofuel in compatible refinery “location”. The properties of HDT-Bio-oil as well as fossil-based refinery intermediates were compared, and five fossil-based refinery intermediates have been concluded as potential candidates for co-processing. The analysis was based on mapping several petroleum fractions’ quality properties (i.e., boiling curve, gravity/density, overall elemental composition, viscosity, surface tension) within a conventional refinery. Based on the comparative assessment, the following refinery streams have been identified as potential candidates for co-processing with HDT-Bio-oil: Straight Run Distillate Diesel (SRGO), Atmospheric Gasoil (GASOIL), Light cycle oil (FCC LCO), Heavy cycle oil (FCC HCO) and Light vacuum gas oil (LVGO). Furthermore, the miscibility of the aforementioned renewable and conventional fuel intermediates has been investigated via light microscopy. In particular, the five mixtures of bio-oil/refinery intermediates were observed under Nikon ECLIPSE TE2000- S optical microscope. Among all refinery streams, Fluid Catalytic Cracking Light Cycle Oil (FCC LCO) and secondly Light Vacuum Gas Oil (LVGO) have been concluded to be the most promising candidates for coprocessing, resembling HDT-Bio-oil’s properties. The study is part of the “BioMates” Horizon2020 research and innovation EU project, aspiring in combining innovative 2nd generation biomass conversion technologies for the cost-effective production of reliable bio-based intermediates that can be further upgraded in existing oil refineries as renewable and reliable co-feedstocks. Therefore, the current miscibility study acts as a prescreening of candidate feedstocks for the targeted hydroprocessing study that will follow.

No abstract.