Fuels & Lubricants Magazine

GREEN CORNER
The advantage of pyrolysis
oil in comparison with direct
using of biomass is easy
handling, transport, storage
and utilization.
cost of the biomass feedstock used to produce it. Incentives
to replace fossil fuels or CO 2
reduction targets
improve the economics further. 4
One of the alternatives for the advanced biofuel
increasing is co-feeding or co-processing of biomass-derived
feedstock as bio pyro oil in a blend with conventional
petroleum feedstock in typical refinery units. 5
This concept has advantages in comparison with conventional
biofuel production. The co-processing uses
existing refining infrastructure: units, catalyst, utilities,
and it needs a low investment of refinery system modifications.
The bio pyrolysis oil can be utilized in FCC process in
conventional refinery configuration. FCC is one of the
most important secondary refinery processes for gasoline
production.
The oleaginous raw material as vegetable oil used
cooking oil and animal fat can also be co-processed in
refinery besides bio pyro oil co-processing.
Legislation and Emissions
The main goal of current European legislation is the
reduction of greenhouse gas emission (GHG) and carbon
footprint. Oil and gas industry tries to produce clean
transportation fuels by adding of different biofuels in
traditional motor fuels.
Biofuels from the first generation as bioethanol and
fatty acid methyl ester (FAME) are limited by current
and future legislation. The highlight is on advanced
biofuels processed from algae, animal manure, lignocellulose
and other waste material.
EU requires from Member States fuel suppliers to
include a minimum share of energy from advanced
biofuels, biogas, renewable fuels of non-bio origin and
renewable electricity from Y2021 according to Draft of
Renewable Energy Directive 2 (RED 2). 6 The minimum
share of renewables is 1.5 % in Y2021 and will increase
up to 6.8 % in Y2030 according to the current proposal.
Within this total share, the contribution of advanced
biofuels and biogas shall be at least 0.5 % in Y2021, increasing
up to 3.6 % by Y2030.
Directive 2015/1513, so-called ILUC Directive
7 recognised this type of wood waste material and
implemented them in Annex 9. All EU Member States
have had obligation to implement Directive until the end
of 2017.
GHG savings of the raw pyrolysis oil according to the
literature are really high and above of other biofuels and
it is about 85-95% for heat and power applications. In
comparison with favourable fossil fuel, the combustion
emission is significantly reduced. The abatement of over
99 % of SO X
emission, over 36 % of NO X
emission and
over 72 % of CO emission are noticed. 8
Properties of Bio Pyrolysis Oil
The bio pyrolysis oil is completely different material
from fossil oils which complicate their usage in the
petroleum industry as motor fuels. Unique physical and
chemical properties of bio pyro oil make it very challenging
from the analytical point of view.
Bio pyrolysis oil was used primarily in boilers and furnaces
as fuel oil replacement for electricity and heat production.
The properties of bio pyro oil for this purpose is
described by ASTM D 7544 method. 9
It is described by International Energy Agency (IEA)
as: “Product of thermal treatment of lignocellulosic biomass,
typically at between 450-600 °C at near atmospheric
pressure or below, in the absence of oxygen using
small dry biomass particles. The solid by-product is char.
Bio pyro oil is complex mixture oxygenated hydrocarbon
fragments derived from biopolymer structures. It typically
contains 15-30 wt. % of water. Common organic components
include acetic acid, methanol, aldehydes and ketones,
cyclopentenones, furans, alkyl-phenols, alkyl-methoxy-phenols,
anydro sugars and oligomeric sugar water insoluble
lignin-derivate compounds. Nitrogen- and sulphur containing
compounds are also sometimes found depending on
biomass source”. 10
The bio pyro oil composition is very complex and varies
in accordance with biomass feedstock, process and
operating conditions. Typical properties of bio pyro oil
are present in Table 1. 10
The bio pyro oil is highly polar material, miscible with
polar fuels. It contents between 15 to 30 wt. % of water
in a microemulsion. Water is undesirable components in
motor fuels due to corrosion effect, emulsion formation
and problems in burners. Oxygen content is very high
accordingly. The acidity of bio pyro oil is also high, so
corrosion effect can be expected as well. Viscosity is very
high and it is connected to combustion and engine application.
Viscosity is increased by ageing and depends
on temperature. Pour point is satisfied to compare to
Fuels&Lubricants No. 2 JUNE 2018 31