Sustainability 14 13083

sustainability
Article
Biofuel Technologies and Petroleum Industry: Synergy of
Sustainable Development for the Eastern Siberian Arctic
Kirill A. Bashmur 1 , Oleg A. Kolenchukov 1 , Vladimir V. Bukhtoyarov 1,2 , Vadim S. Tynchenko 1,2,3, * ,
Sergei O. Kurashkin 2,3,4, * , Elena V. Tsygankova 5 , Vladislav V. Kukartsev 2,6,7 and Roman B. Sergienko 8
1 Department of Technological Machines and Equipment of Oil and Gas Complex,

School of Petroleum and Natural Gas Engineering, Siberian Federal University, 660041 Krasnoyarsk, Russia
2 Digital Material Science: New Materials and Technologies, Bauman Moscow State Technical University,
105005 Moscow, Russia
3 Information-Control Systems Department, Institute of Computer Science and Telecommunications,
Reshetnev Siberian State University of Science and Technology, 660037 Krasnoyarsk, Russia
4 Laboratory of Biofuel Compositions, Siberian Federal University, 660041 Krasnoyarsk, Russia
5 Department of Foreign Languages for Natural Science, Siberian Federal University,
660041 Krasnoyarsk, Russia
6 Department of Informatics, Institute of Space and Information Technologies, Siberian Federal University,
660041 Krasnoyarsk, Russia
7 Department of Information Economic Systems, Institute of Engineering and Economics,
Reshetnev Siberian State University of Science and Technology, 660037 Krasnoyarsk, Russia
8 Machine Learning Department, Gini Gmbh, 80339 Munich, Germany
* Correspondence: vadimond@mail.ru (V.S.T.); scorpion_ser@mail.ru (S.O.K.); Tel.: +7-95-0973-0264 (V.S.T.)
Citation: Bashmur, K.A.;
Kolenchukov, O.A.; Bukhtoyarov, Abstract: This article is a compilation of interdisciplinary studies aimed at ensuring the environmen-
V.V.; Tynchenko, V.S.; Kurashkin,
tal, political, and economic sustainability of oil and gas-producing countries with a focus on areas
S.O.; Tsygankova, E.V.; Kukartsev,
with many years of permafrost. One of the main concepts adopted in this research was the desire
V.V.; Sergienko, R.B. Biofuel
to show that confronting various energy lobbies is not mandatory and that it is necessary to find
Technologies and Petroleum
compromises by finding and introducing innovative technologies for integrated development for the
Industry: Synergy of Sustainable
Development for the Eastern Siberian
benefit of society, industry, and the state. This is particularly relevant due to the increasing share of
Arctic. Sustainability 2022, 14, 13083. hard-to-recover hydrocarbon reserves, widely represented in the fields of the Eastern Siberian Arctic,
https://doi.org/10.3390/ and because Russia is the leader in flare emissions. We thus present the relevance of using these
su142013083 gases as industrial waste while reducing the carbon footprint. The technology of biofuel production
based on the use of supercritical liquid extraction in a well extractor is presented as a result of the
Academic Editors: Mohammad
development of the presented experimental devices representing the investigation of the processes of
Sadegh Allahyari and Amin
Nikkhah
extraction in wells and reactors for the distillation of hydrocarbons from heavy oil components. The
obtained yield of the desired product (hydrogen) of the thermocatalytic pyrolysis of the test extract
Received: 22 August 2022 was in the range of 44 to 118 L/h, depending on the catalyst. This information can help inform the
Accepted: 29 September 2022
direction of future ecological engineering activities in the Eastern Siberian Arctic region.
Published: 12 October 2022
Publisher’s Note: MDPI stays neutral Keywords: biofuel production; biogas; supercritical fluid extraction; carbon dioxide; oil sludge;
with regard to jurisdictional claims in waste-to-energy; pyrolysis
published maps and institutional affil-
iations.
1. Introduction
Copyright: © 2022 by the authors.

Significant changes in global energy markets have recently been reflected as the
Licensee MDPI, Basel, Switzerland.
growing need for energy, to develop and improve the efficiency of technology, to toughen
This article is an open access article environmental standards, etc. [1]. This shows that energy security and well-being are
distributed under the terms and increasingly complex and multifaceted. These issues are increasingly included in the
conditions of the Creative Commons priorities discussed by leaders of all countries, at the level of congresses, forums, symposia,
Attribution (CC BY) license (https:// and other meetings in business circles, as well as in scientific communities.
creativecommons.org/licenses/by/ The concept of the Energy Trilemma developed by the World Energy Council focuses
4.0/). on three main vectors of development of the fuel and energy complex: energy security,
Sustainability 2022, 14, 13083. https://doi.org/10.3390/su142013083 https://www.mdpi.com/journal/sustainability

Sustainability 2022, 14, 13083 2 of 25
energy availability, and environmental sustainability. Economics, politics, and environ-

mental protection are the three competing objectives of the energy trilemma [2,3] and their
balance is the subject of years of contention from different perspectives. With the United
Nations Sustainable Development Goals and the Paris Climate Agreement already being
implemented in the world [4], the need for energy to contribute to the stable develop-
ment of the world community should be clear and significant. Energy generation is now
determined not only by economic indicators of feasibility but also by the growing social
and environmental factors of society, corresponding to several side-by-side sustainable
development paradigms presented by the UNO. The link between goal 7, “Achieving
universal access to affordable, reliable, sustainable and modern energy for all”, and goal 13,
“Taking urgent action to combat climate change and its consequences,” supported by the
Paris Agreement international climate change treaty, is clear.
At the same time, there are justifiably more stringent requirements for ensuring
energy security for facilities and farms that operate in territories in difficult conditions,
in conditions of extreme climates, and in infrastructure isolation [5,6]. The creation of
comfortable conditions for the functioning of human society and quality of life is coupled
with a number of difficulties. The survival of mankind as a whole depends significantly on
how much we can learn to live in a new way, that is, to protect nature and resources as much
as possible, to introduce and use environmental and knowledge-intensive technologies,
and to generate income with limited physical and energy resources.
The importance of addressing interrelated issues in this direction occurs due to the
problem of a reliable energy supply in the developing northern and Arctic territories. Strate-
gic guidelines for sustainable energy development are interesting and are identified and
traced in the strategies of the countries of the Arctic region group: Russia, Canada, the USA,
and Scandinavian countries [7–9]. This largely explains the particular importance of energy
security, as expressed in the declaration of international organizations and regional associa-
tions, as well as in national energy strategies and laws. Energy systems located in remote
areas can face many specific challenges, such as transport logistics problems, including
limited fuel and spare parts supply during the year and the dependence of these supplies
on weather conditions, and the lack of qualified field maintenance personnel [10,11].
We conclude that it is necessary to jointly study environmental and economic oppor-
tunities for the development of the energy complex, including renewable energy source
(RES) technologies, which is consistent with the position of the authors of the study [12]. It
is also necessary to do this individually for each case or region, as development decisions
should be made on the basis of the reasonable use of natural capital, reduction in emissions,
conservation of biological diversity, as well as the payback and efficiency of the project.
For example, due to the fact that the northern and Arctic zones of Eastern Siberia
are climatically severe, underdeveloped, and poorly populated territories with large ex-
plored and exploited oil and gas reserves (33 hydrocarbon deposits of the Krasnoyarsk
Territory) [13], the problems of the fuel and energy complex here are extreme. In the cold
season, the rivers and the Northern Sea Route freeze, and only aviation and winter roads
(routes along frozen rivers) are the modern transport routes to the north of Eastern Siberia.
Fuel imported to the fields and purchased by oil and gas companies is necessary for the
operation of numerous technological units, machines, and equipment, as well as for their
own needs (heating and electricity generation). Thus, a significant carbon footprint is
generated in these fields. At the same time, an even greater carbon footprint is made by
the burning flares of the oil production by-product, i.e., the associated gas and methane,
carbon dioxide, and other gases formed as a result of combustion, which are due to the
limited technological capabilities for the use and storage of gas [14].
Table 1 shows the countries with the highest emissions from gas combustion in 2020
and 2021 at oil production facilities [15]. It follows that Russia is the leader in these emis-
sions and does not have a downward trend, unlike most other countries. Flare gases, and
in particular CO2 , are referred to as greenhouse gases, and emissions into the atmosphere
of this by-product are the root cause of global climate change [16,17]. At the same time,
climate change contributes to the increase in the number of fires in Eastern Siberia, which,
in turn, adds to the obvious harmful environmental impact and contributes to the increase
in emissions [17–19].
Table 1. Gas flaring data [15].
Gas Gas Flaring Volume

Country
Flaring Volume (bcm/Yr)—2020 (bcm/Yr)—2021
Russia 24.9 25.4
Iraq 17.4 17.8
Iran 13.3 17.4
United States 11.8 8.8
Algeria 9.3 8.2
Venezuela 8.6 8.2
Nigeria 7.2 6.6
Given that most of the mentioned deposits have yet to be commissioned, this problem
is significant for the sustainable development of Arctic territory society, nature, and fauna.
Today, the need to dispose of man-made carbon dioxide, in the framework of the Paris
Climate Agreement signed by the world community, is more important than ever before. At
the same time, many countries, such as Russia and China, adhere to the strategy of a more
moderate transition to the reduction in greenhouse gas emissions and the introduction
of RES by 2060 [20]. This is naturally dictated by the dependence of the economies of
these countries on hydrocarbons and the sluggish dynamics of the introduction of electric
generating capacities operating on renewable energy. At the same time, the Order of the
Government of the Russian Federation dated 1 June 2021 No. 1447-r states, in particular,
about the upcoming increase in oil production, “On approval of the action plan for the
implementation of the Energy Strategy of the Russian Federation for the period up to
2035” [21].
In this situation, following the logical reasoning of the authors of the study [22], it can
be assumed that an increase in the share of RES will lead to a decrease in CO2 emissions.
At the same time, considering the existing technologies in the field of renewable energy
in relation to the northern and Arctic zones of Eastern Siberia, we do not see ready-made
solutions. In particular, unique solutions are known in the field of solar energy production
and storage in the Arctic zone of Alaska [23,24]. However, in winter (on Polar Night),
the potential of solar energy in the Arctic drops significantly. This means that the energy
systems of the Arctic cannot be completely dependent on solar energy, even in combination
with batteries or other storage solutions, i.e., in winter, a backup power source is always
required in the Arctic. In addition, snow deposition on batteries during temperature
spikes and regular blizzards requires frequent regular maintenance. Ensuring the dynamic
development of wind energy in the Arctic is also a big question. There is growing concern
about the ability of wind farms to withstand and restore their performance in the event
of failures [25]. Issues of the reliability of wind turbines also have a significant role; in
particular, problems with their icing [26] and failure of bearings [27] are known.
It is also known that energy can be obtained from various types of raw biomass mate-
rials, including agricultural waste, livestock waste, solid household waste, and other types
of organic waste [28–30]. Due to a variety of processes, this feedstock can be used directly
for the production of electricity or heat, or can be used for the production of gaseous, liquid,
or solid fuels; biodiesel, bioethanol, and biogas are considered the most promising [31–33].
The most promising biogas-based fuels are hydrogen mixtures and hydrogen, which can
reduce greenhouse gas emissions when replacing natural gas without changing the combus-
tion technology [34]. Thus, pure biofuels, or, more commonly, biofuels mixed with oil-based
fuels, can be used in liquid fuel systems for use in process equipment, transport, or heating.
The range of bioenergy technologies is wide, and the level of their technical development
varies considerably [35]. For example, according to existing research findings [36,37], the
effect of hydrogen enrichment leads to a reduction in hydrocarbon emissions and soot from
the gas engine and contributes to improved engine energy efficiency and fuel economy.
This is particularly relevant to the Eastern Siberian Arctic area where a large number of
diesel generator sets are used for heating and oil tankers run on diesel engines, i.e., the
relevance of converting engines and generators to a gas-diesel format or using gas engines,
in general, is increasing.
Due to its harsh climatic conditions, the Eastern Siberian Arctic is not rich in raw
materials for the production of biofuels, however, this study shows non-trivial approaches
to its production. In particular, among a number of suitable raw materials for the production
of biofuels in the Eastern Siberian Arctic, the authors include wastes from the petroleum
industry, which is further discussed below. It is worth noting that hydrogen and hydrogen-
containing mixtures are quite difficult to transport and store [38], but in this case, the harsh
climate conditions of the Eastern Siberian Arctic best contribute to the development of
technologies for storing and transporting hydrogen in a gas-hydrate state [39].
In addition to flare gas, the petroleum industry produces large quantities of other
industrial waste, i.e., oil sludge [40], as well as physically and chemically similar and
unprofitable to extract and transport heavy oil. Oil sludge is a hazardous toxic waste on
the one hand and a valuable energy resource on the other [40,41]. One approach to the
environmentally friendly treatment of sludge is deep thermal decomposition based on
the pyrolysis process [42]. Steam treatment or dissolving carbon dioxide CO2 is known to
enhance the physical properties of heavy oil [43,44]. For high-viscosity oil, the degree of
viscosity reduction when carbon dioxide is dissolved in it is comparable to the reduction in
viscosity when exposed to heat [45]. Steam treatment in an area of permafrost can lead to
serious equipment accidents [46]. It is also known that CO2 injection can accelerate biomass
thermal cracking which increases the yield of gaseous pyrolysis products hydrogen and
methane [47,48]. These prerequisites predetermine the need to develop a comprehensive
technology for waste management, processing, and utilization in the Eastern Siberian Arctic
fields, with an assessment of the energy resources obtained on the basis of known biofuel
production technologies.
The authors of the study [49] predicted a serious confrontation between the green
lobby, the shale industry, and the traditional oil industry in the near future. We already see
signs of this confrontation in connection with the Arctic development strategy published by
the European Union where there is a call for an early ban on the exploration and production
of oil, gas, and coal in the Arctic [50]. Such political statements do not facilitate dialogue
with supporters of a moderate transition strategy and, against the background of the
European energy crisis of 2021/2022 [51,52], look unstable, since, for example, a significant
share of gas imported by Europe is produced and supplied on the Yamal Peninsula, one of
the key gas production centers of the Arctic Zone [53]. One of the tasks set in our study
was the desire to show that confronting various energy lobbies is not mandatory and that
it is necessary to find compromises, in particular, by finding and introducing innovative
technologies to develop broadly, not for the sake of individual positions, but for the benefit
of society. As the authors of the study [54] showed, this is especially relevant due to the
increasing share of hard-to-recover hydrocarbon reserves (heavy and high-viscosity oil)
widely represented in fields in the Arctic since the low temperature in such reservoirs
prevents the ideal maturation of hydrocarbons. It also limits the ability to extract hard-to-
recover hydrocarbons and increase oil recovery by thermal techniques which can cause
permafrost melting and can lead to wellbore collapse, requiring the development of unique
solutions and/or other techniques such as CO2 injection [55].
The set of non-trivial solutions presented in this study is based on the introduction of
green environmental technologies into established mining processes, leading not only to
a decrease in the carbon footprint but also to potential economic benefits for oil and gas
companies. The main purpose of this study is to evaluate an oilfield-adapted integrated
biofuel technology based on the supercritical extraction and thermal decomposition of the
feedstock—waste products. The choice is justified by the analysis of the Eastern Siberian
Arctic bio-resource potential stability for the region’s sustainable development.
of green environmental technologies into established mining processes, leading not only
to a decrease in the carbon footprint but also to potential economic benefits for oil and gas
companies. The main purpose of this study is to evaluate an oilfield-adapted integrated
biofuel technology based on the supercritical extraction and thermal decomposition of the
Sustainability 2022, 14, 13083 feedstock—waste products. The choice is justified by the analysis of the Eastern Siberian 5 of 25
Arctic bio-resource potential stability for the region's sustainable development.
To achieve this goal, it is necessary to present a concept for the production of biofuels
on an industrial
To achieve scale
this in theitconditions
goal, is necessaryof to
hydrocarbon deposits
present a concept for in
thethe Eastern Siberian
production of biofuels
Arctic.
on an industrial scale in the conditions of hydrocarbon deposits in the production
The stage of this task was the development of technology for the of
Eastern Siberian
biofuels in the conditions of the East Siberian Arctic field by adapting
Arctic. The stage of this task was the development of technology for the production ofknown methods for
thebiofuels
production of biofuels
in the conditions andofstudying
the East the sources
Siberian of suitable
Arctic field by raw materials.
adapting knownTo predict
methods
thefor
behavior of the biofuel
the production production
of biofuels andsystem
studyingin Arctic fields based
the sources on theraw
of suitable proposed tech- To
materials.
nology, thethe
predict task was setof
behavior tothe
develop
biofuelanproduction
experimental bench
system for thefields
in Arctic studybased
of theon well
theextrac-
proposed
tiontechnology,
process. The next
the tasktask
was wassetto
toexperimentally investigate bench
develop an experimental the process
for theof study
extracting
of thehy-
well
drocarbon substances from heavy petroleum components by extracting carbon
extraction process. The next task was to experimentally investigate the process of extracting dioxide in
a supercritical
hydrocarbon state, followed
substances by heat
from heavytreatment
petroleum of components
the obtainedby substances
extractingtocarbon
obtaindioxide
useful in
products. A qualitative
a supercritical and quantitative
state, followed composition
by heat treatment assessment
of the obtained was then performed
substances on
to obtain useful
theproducts.
products obtained.
A qualitativeIn addition, one of thecomposition
and quantitative main tasks of this studywas
assessment wasthen
to demonstrate
performed on
thethe
possibilities for synthesizing
products obtained. existing
In addition, onemining technologies
of the main tasks of and green was
this study energy.to demonstrate
the possibilities for synthesizing existing mining technologies and green energy.
2. Development of Biofuel Production Technologies Using Supercritical Fluid Extrac-
tion2. Development of Biofuel Production Technologies Using Supercritical Fluid
Extraction
2.1. Supercritical Fluid Extraction Technology
2.1. Supercritical Fluid Extraction Technology
A typical supercritical fluid extraction (SFE) scheme is shown in Figure 1 [56,57]. The
A typical supercritical fluid extraction (SFE) scheme is shown in Figure 1 [56,57]. The
main equipment of this technology include (Figure 1): cylinders with solvent, 1, and co-sol-
main equipment of this technology include (Figure 1): cylinders with solvent, 1, and co-
vent, 2; a pressure pump, 4; extractor, 6; pressure vessel, 7; and separator, 8, where the extract
solvent, 2; a pressure pump, 4; extractor, 6; pressure vessel, 7; and separator, 8, where the
is accumulated and separated.
extract is accumulated and separated.
Figure 1. Supercritical extraction flow diagram. 1—supercritical CO2 ; 2—co-solvent; 3—proportioning

manifold; 4—pumps; 5—heat exchanger; 6—extractor; 7—back pressure regulator; 8—separator;
9—extract; 10—microencapsulated products; 11—essential oil.
As noted in [58], the most important condition for SFE is the choice of solvent. As
the temperature rises at constant pressure, the density of the gases decreases, causing the
dissolving capacity of the gases to decrease. The concentration of solute in the dense gas
increases as a result of the reaction of the solvent and the increase in vapor pressure of the
solute as the temperature and pressure increase. Consequently, the effect of temperature
on the solubility of a substance in a supercritical fluid varies with pressure. As a rule, an
increase in pressure leads to an increase in solubility. Therefore, substances with high critical
temperatures are better solvents, i.e, water, than gases with low critical temperatures.
solving capacity of the gases to decrease. The concentration of solute in the dense gas in-
creases as a result of the reaction of the solvent and the increase in vapor pressure of the
solute as the temperature and pressure increase. Consequently, the effect of temperature
on the solubility of a substance in a supercritical fluid varies with pressure. As a rule, an
Sustainability 2022, 14, 13083 increase in pressure leads to an increase in solubility. Therefore, substances with high6crit- of 25
ical temperatures are better solvents, i.e, water, than gases with low critical temperatures.
It should be noted that due to the high critical parameters (374 °C, 22 MPa) [59,60],
supercritical
It shouldwater for industrial
be noted that dueuse is ahigh
to the low-attraction solvent. Therefore,
critical parameters the
(374 ◦ C, 22 most[59,60],
MPa) often
used solvent for SFE is carbon dioxide, since CO 2 in the supercritical state is at a moderate
supercritical water for industrial use is a low-attraction solvent. Therefore, the most often
critical temperature
used solvent for SFE(31.1 °C) and
is carbon pressure
dioxide, since(7.38
CO2MPa)
in the[60,61]. In addition,
supercritical state isCO is a non-
at a2 moderate
toxic,
critical temperature (31.1 C) and pressure (7.38 MPa) [60,61]. In addition, CO2 isCO
inexpensive, and easily
◦ removable substance from the obtained extract since 2 is
a non-
in a gaseous state at room temperature [62].
toxic, inexpensive, and easily removable substance from the obtained extract since CO2 is
in a The disadvantages
gaseous state at room of temperature
SFE include [62].
the complexity of manufacturing equipment for
high pressures
The disadvantages of SFE include therequired
and the need to maintain the complexity process temperature between
of manufacturing equipment 35 and
for
90 °C [63].
high pressures and the need to maintain the required process temperature between 35 and
90 ◦ C [63].
2.2. Potential of Application of SFE Technology for Biofuel Production in Downhole Conditions
2.2. Potential of Application
The described of SFE Technology
SFE technology for Biofuel
can be adapted forProduction in Downhole
the well stock Conditions
of hydrocarbon de-
posits.The
Duedescribed
to the factSFEthattechnology
every year can be adapted
the number for the well
of abandoned oil stock
and gasof wells
hydrocarbon
grows,
deposits. Due to the fact that every year the number of abandoned oil
for example, they number about 2 million in the USA alone, causing methane emissions and gas wells grows,
for example,
and they number
other environmental about 2[64,65],
damage millionwe in propose
the USA using
alone,the
causing
wells methane emissions
as an extractor for
andproduction
the other environmental
of biofuels damage [64,65], we
on an industrial propose
scale. using
The well canthe
actwells as an extractor
as a natural for
reactor for
the production
chemical reactions of biofuels
and biofuel on an industrial scale. The well can act as a natural reactor for
extraction.
chemical reactions and
The operation biofuel
in [66] showsextraction.
the parameters of temperature and pressure as well as
The operation in [66] shows
depth increases during carbon dioxide the parameters
injection. Fromof temperature
this work, it and pressure
follows that asasthe
well as
well
depth increases during carbon dioxide injection. From this work, it follows
is deepened, the parameters necessary for the supercritical extraction of biofuels can be that as the well
is deepened,
obtained. It can the parameters
also necessary
be noted that oil and for
gasthe
wellsupercritical
equipment isextraction
designedof forbiofuels can be
high pressure
obtained.
and It can also
temperatures be noted that oil and gas well equipment is designed for high pressure
[67].
and Figure
temperatures [67].
2 shows the developed conceptual technology of the downhole extraction pro-
Figure
cess with flare2 shows the developed conceptual technology of the downhole extraction
gas utilization.
process with flare gas utilization.
Figure 2. Conceptual diagram of biofuel production using a well. 1—flare; 2— CO2 production unit;
3—CO2 storage tank; 4—raw material storage tank; 5—heating inserts; 6—tubing string; 7—casing
(well); and 8—separator or thermal destruction unit.
Flare gas in oil and gas fields can be collected and moved by means of water-ring
compressors [68] or ejectors [69].
The next stage of biofuel production technology is the supply of flare gas to the power
generation and cogeneration plants, as well as to the ammonia production plant based
on the Gaber process, the possibility of which is described in [70]. At the same time, flare
gas energy is converted into electricity and heat in power generation and cogeneration
plants, respectively. When the produced electricity and heat are supplied to the ammonia
production plant based on the Gaber process, the following products useful for technology
are obtained [71]: ammonia, 2NH3, and high purity CO2, carbon dioxide. The obtained
ammonia can be supplied to the annular well space for heating the tubing string and
its contents.
The resulting CO2 and biofuel feedstock can be stored in pressurized tanks at
0.8 MPa [72]. CO2 can also be stored in liquid form at a temperature of approximately −18
. . . −24 ◦ C. Negative temperatures in the northern and Arctic territories can be achieved
naturally in winter, and in summer by using a refrigeration unit consisting of compressors
and refrigerant condensers. Heat stabilizers with forced circulation may be an alternative to
refrigeration units. To date, thermal stabilizers are used to cool the foundations of oil tanks
in the northern fields, for example, at the Vankor field [73]. The insulation addition cooling
system can minimize operating costs and reduce CO2 losses resulting from evaporation
due to pressure and temperature differences, such as through valve devices. Usually,
before being fed into the tanks, CO2 is dewatered when its dew point drops to below 0 ◦ C
and compressed to critical pressure [74]. Underground CO2 storage can also be used in
combination with terrestrial tanks [75].
The feedstock and CO2 can be sequentially pumped into the tubing column by means
of a Christmas tree, which thus acts as an extractor. In this case, CO2 is brought to a
supercritical state by pre-compression, or sequential injection into the tubing column or
throttling, as well as heating, using heating inserts, NH3 , or a set of methods.
A further step is the phase separation of the extract and, depending on the raw material
used, it can be either separation, heat treatment, or a set of methods. In particular, when
using raw hydrocarbon materials, i.e., oil sludge, extract can be decomposed by thermal
destruction methods into hydrocarbon gases and then into pure hydrogen, which can be
carried out using one sectional pyrolysis plant [76]. Thus, we find the technology of the
fixated production of biofuels at the existing injection or abandoned (liquidated) wells with
the disposal and/or use of waste produced in the form of flare gases and heavy oil.
Today, there is the practical experience of CO2 injection into the oil reservoir and when
developing this technology, it is necessary to take into account this practical experience [77].
Table 2 shows the recommended materials for CO2 injection [78].
Table 2. Recommended materials for CO2 injection into the well [78].
Construction Design Material

Measuring sections of pipelines 316 SS stainless steel and fiberglass
Christmas tree (lining) 316 SS steel, nickel, and Monel metal
Packing and sealing of valves Teflon and nylon
Wellhead (lining) 316 SS steel, nickel, and Monel metal
Tubing suspension 316 SS steel and Incoloy alloy
Glass Reinforced Epoxy (GRE),
Tubing strings Internal Plastic Coating (IPC), and Corrosion
Resistant Alloy Pipes (CRA)
GRE sealing rings, IPC thread, and
Tubing connections
coupling coating
Disconnecting adapter Nickel coating of contacting parts and 316 SS steel
Hardened rubber with inner coating and nickel
Packers
coating of contacting parts
API cements and/or special acid-resistant cements
Cements and cement additives
and additives
2.3. Overview of Raw Materials for Biofuel Production in the Eastern Siberian Arctic
Next, we will review the most common raw materials in terms of energy potential for
biofuel production in the Eastern Siberian Arctic.
We divided the most common raw materials into groups (Figure 3).
Cements and cement additives
ments and additives
2.3. Overview of Raw Materials for Biofuel Production in the Eastern Siberian Arctic
Next, we will review the most common raw materials in terms of energy potential
for biofuel production in the Eastern Siberian Arctic.
We divided the most common raw materials into groups (Figure 3).
Figure 3. Main raw materials

Figure 3. Mainforraw
biofuel production.
materials (a) Biological
for biofuel objects
production. (a)(e.g., algae);objects
Biological (b) fiber
(e.g., algae); (b) fiber
sources (e.g., wood and paper waste); and (c) by-products of enterprises and people’s activities
sources (e.g., wood and paper waste); and (c) by-products of enterprises and people’s activities
(e.g., organic waste).
(e.g., organic waste).
1. The energy 1. potential of biological

The energy potentialobjects such as
of biological corn,such
objects soybeans,
as corn,algae (Figure
soybeans, 3a),(Figure 3a), etc.
algae
etc. This raw material group for biofuel production is quite stable in terms
This raw material group for biofuel production is quite stable in terms of cheapness,of cheap-
ness, high biomass
highaccumulation,
biomass accumulation,and rapid and reproduction as well as the
rapid reproduction global
as well as prop-
the global property
erty qualities ofqualities
the resulting fuel [79] or its potential [80], to a greater
of the resulting fuel [79] or its potential [80], to a greater or lesser extent,or lesser extent,
depending on depending
specific rawon material,
specific i.e.,
rawitmaterial,
allows cyclically
i.e., it allowsgrowing and obtaining
cyclically growing and obtaining
energy, reducing negative
energy, impacts
reducing on the ecosystem
negative impacts on and thereplacing
ecosystem traditional energytraditional en-
and replacing
sources [81]. Oilergy
extracts obtained
sources [81]. from the presented
Oil extracts obtained rawfrommaterials can be converted
the presented raw materials can be
to bioethanol [82] and biodiesel
converted [83]. Highly
to bioethanol productive
[82] and biodieselenergy plants productive
[83]. Highly such as Jatrophaenergy plants such
curcas [84] do not survive in the Eastern Siberian Arctic due
as Jatropha curcas [84] do not survive in the Eastern Siberian to harsh soil andArctic
climatic
due to harsh soil
conditions. In and
the south
climaticof conditions.
the region,In experiments
the south ofhave been conducted
the region, experiments to have
createbeen conducted
fast-growing transgenic plants based
to create fast-growing on aspenplants
transgenic and based
poplaron[85,86].
aspen andHowever,
poplar the
[85,86]. However,
industrial cultivation of transgenic
the industrial plants
cultivation ofin the Russian
transgenic Federation
plants is prohibited.
in the Russian Federation is prohibited.
2. Pulp (fiber),
2. wood,
Pulp and paper
(fiber), wood,waste and (Figure
paper3b) as raw
waste materials.
(Figure 3b) asFiber is found inFiber is found
raw materials.
in the
the stems of plants andstems
treesof[87].
plantsThus,andintrees [87].
order Thus, biofuels,
to obtain in order to obtain
fiber can be biofuels,
pro- fiber can be
produced
duced and processed, andmakes
which processed, whichtomakes
it possible establish it possible
an almost to establish
continuous antech-
almost continuous
technological
nological process. Waste from process. Waste fromalso
wood processing wood processing
contains alsocan
fiber and contains
be used fiber and can be
used to
to produce biofuels. produce biofuels.
Bioethanol is mainlyBioethanol
obtained from is mainly obtained from fiber [88].
fiber [88].
3. 3.
For the Eastern For the Eastern
Siberian Arctic, Siberian Arctic, we
we identified rawidentified
materialsraw suchmaterials such as the by-products of
as the by-products
enterprises
of enterprises and and human
human activities activitiesand
(emissions (emissions
waste) and as wellwaste) as well as
as yedoma yedoma (Figure 3c).
(Figure
In particular, both independent gases (methane,
3c). In particular, both independent gases (methane, hydrogen, etc.) and those ob- hydrogen, etc.) and those obtained by
tained by the processing of certain raw materials can be used as biofuels (biogas). For For example,
the processing of certain raw materials can be used as biofuels (biogas).
example, organic organic
wastewaste
underunder the influence
the influence of certain
of certain microbesmicrobes decomposes
decomposes to form to form methane
gas, which can be collected for further use [89]; when the produced gas is ignored, a
greenhouse effect is formed.
Thus, the most interesting process includes the processing of hydrocarbon and house-
hold waste, which we also divided into three groups.
The first group includes used oils and lubricants [90,91], i.e., oil spills, emulsions, and
heavy oil components which cannot be mined or processed by conventional methods [92].
Every year the number of abandoned wells increases, due to the heavy and contaminated
residue of raw oil materials which is difficult to produce and transport [93]. Meanwhile, the
wells are preserved and heavy oil fractions can be used as feedstock for biofuel production.
Different emulsions formed during oil storage and oil spills are classified as oil sludge,
from which, with proper processing, it is possible to obtain different types of biofuels.
The second group includes solid household waste consisting of organic materials [94].
The advantage of using this kind of raw material lies in the possibility of controlling the
final product (from gases to liquids and solid residues). In particular, it is possible to
obtain hydrogen [95], which, when burned, forms only water, making this type of fuel
environmentally friendly.
The third group includes raw materials such as yedoma. Frozen yedoma is the relict
soil of the giant steppe-tundra ecosystem which occupied the territory of Siberia, Alaska,
and part of Canada in glacial times [96]. Yedoma is essentially an organic material consisting
of dead plants, animals, and microbes that has not broken down and accumulated carbon
for thousands of years [97]. The main danger of yedoma to the ecosystem is the production
of greenhouse gases, methane, carbon dioxide, and nitrous oxide, which are formed when
the temperature of yedoma increases past the freezing point. At the same time, the organic
part of yedoma can be of practical interest for processing, by drilling wells and collecting
and processing organics [98,99].
Thus, some non-trivial ways of using raw materials for biofuel production for the
sustainable development of the north of the East Siberian region are discussed, often
requiring the development of appropriate technologies for the production of raw materials
and biofuels themselves, characterized by minimal environmental impact.
2.4. Review of Impact Methods on Heavy Hydrocarbon Well Fractions for Biofuel Production in the
Eastern Siberian Arctic
There are many methods to date for handling downhole heavy organic components
(the raw materials of the first group mentioned above). We are interested in the possibility
of using these wastes of production for extraction and subsequent processing. The most
common methods of manipulating heavy borehole fractions of hydrocarbons include:
1. Cyclic Steam Stimulation (CSS). This method consists of the periodic (pumping-
stopping-pumping) injection of hot steam into heavy oil deposits or oil sand deposits
through the common well bore with subsequent recovery of hydrocarbons [100]. The
disadvantages of this method of oil displacement by steam include the need to use
high-quality clean water for steam generators [101] in order to obtain high-quality
steam with a saturation of 80% and a heat capacity of 5000 kJ kg.
2. Steam-Assisted Gravity Drainage (SAGD). This is a widely used method designed
to extract heavy oil components [102]. The difference between the SAGD method
and the CSS method is the drilling of two horizontal wells parallel to each other. The
distance between the wells is usually about 5 m, and the length of the horizontal shafts
is 1000 m. The main drawback is the high cost of oil production by this method [101].
3. Cold heavy-oil production with sand (CHOPS). This method consists of the complex
extraction of oil, together with sand, by the destruction of the weakly cemented
reservoir and the creation of appropriate formation conditions for the flow of a
mixture of oil and sand [103]. To implement this method, it is necessary to use a well
injection scheme that promotes the flow of sand, in addition, there must be enough
dissolved gas in the formation to maintain formation energy.
4. Vapor Extraction (VAPEX). In this method, two horizontal injection and production
wells are used. Hydrocarbon gases (propane, methane-propane, or propane-butane)
are generally used as the solvent. The reduction in the viscosity of heavy oil is achieved
due to heating and dilution with solvent resulting in a mixture of bitumen-solvent that
flows down into the production well [104] by gravity. VAPEX assumes the following
initial conditions: the thickness of the productive formation is more than 12 m; bitu-
men viscosity in formation conditions is more than 600 mPa s; horizontal permeability
is greater than 1000 µm2 ; and vertical permeability is 200 µm2 . According to the
authors of the study [105], the disadvantage of this method is its low performance.
5. Solvent Aided Process (SAP). In this method, a small amount of hydrocarbon solvent
is added as an additive to steam pumped using SAGD technology [106]. While
steam is the main coolant and reduces the viscosity of the oil, the addition of solvent
contributes to its thinning to an even greater extent. The main disadvantage is the
partial loss of solvent that will remain in the well during its injection.
A brief description of the disadvantages of the methods discussed is presented in
Figure 4.
is added as an additive to steam pumped using SAGD technology [106]. While steam
is the main coolant and reduces the viscosity of the oil, the addition of solvent con-
tributes to its thinning to an even greater extent. The main disadvantage is the partial
loss of solvent that will remain in the well during its injection.
A brief description of the disadvantages of the methods discussed is presented in
Figure 4.
Figure 4. Main methods of well production of heavy oil fractions and their disadvantages.
Figure 4. Main methods of well production of heavy oil fractions and their disadvantages.
The most popular method, according to the researchers [105,107] and the authors
The
of this mostispopular
study, method,
the VAPEX according
method. Withtothethediscovery
researchersof[105,107]
using CO and
2 asthe authors of
a solvent, it
became possible
this study, to increase
is the VAPEX efficiency
method. anddiscovery
With the reduce the cost ofCO
of using maintaining
2 as a solvent,theit VAPEX
became
process
possible[108], as well efficiency
to increase as ensure its andsafety
reduce[109],
thewhich makes
cost of this method
maintaining more attractive
the VAPEX process
for implementation
[108], as well as ensure [110].
its In addition,
safety [109], the usemakes
which of the this
supercritical
method morestate attractive
of CO2 obtained
for im-
by supercritical liquid extraction methods allows not only the softening
plementation [110]. In addition, the use of the supercritical state of CO2 obtained by su- of heavy oil
components to facilitate
percritical liquid transportation
extraction but alsonot
methods allows their preparation
only for subsequent
the softening of heavy oilprocessing
compo-
directly
nents toatfacilitate
the production site. but also their preparation for subsequent processing di-
transportation
rectly at the production site.
3. Methodology and Materials of Experimental Studies of Biofuel Production in
Downhole Conditions
3. Methodology and Materials of Experimental Studies of Biofuel Production in11 of 28
Sustainability 2022, 14, x FOR PEER REVIEW
3.1. Raw Materials
Downhole Conditions
To study the extraction process, samples of heavy oil components of the Vankor
3.1. Raw Materials
field of the Krasnoyarsk Territory were used as raw materials. They are a dark brown
To study themixture,
physicochemical
physicochemical extraction
mixture, process,mainly
consisting
consisting samples
mainly ofofof heavy oilproducts,
petroleum
petroleum components
products, of
with
with the Vankor
a water
a water field
content
content of
of
of the
about Krasnoyarsk
9%, and Territory
mechanical were
inclusions used
of as
less raw
than
about 9%, and mechanical inclusions of less than 1% (Figure 5). materials.
1% (Figure They
5). are a dark brown
Figure
Figure 5.
5. Vankor field heavy
Vankor field heavy oil
oil samples.
samples.
The main properties of the raw materials used are shown in Table
Table 3.
3.
Table 3. Main properties of crude oil.
Indicator Value
Oil density, kg/m3 at 20 °С 952
Dynamic viscosity, cP at 20 °С 3.3
Weight content, wt%
aromatic hydrocarbons 35.8
saturated hydrocarbons 50
Table 3. Main properties of crude oil.
Indicator Value
Oil density,kg/m3 at 20 ◦C 952
Dynamic viscosity, cP at 20 ◦ C 3.3
Weight content, wt%
aromatic hydrocarbons 35.8
saturated hydrocarbons 50
asphaltenes 4.4
sulfur 0.149
3.2. Purpose and Functions of Borehole Extraction Test Bench

Sustainability 2022, 14, x FOR PEER REVIEW 12 of 28
The test bench (Figure 6) was designed for the testing process operations of the
extraction method in biofuel production and includes a process control system.
Figure 6. General
Figure 6. General view
view of
of the
the borehole extraction test
borehole extraction test bench.
bench.
bench was
The bench wasdesigned
designedtotoinvestigate
investigate the
the parameters
parameters of of
thethe extraction
extraction process
process in
in the
the well casing using tubing, as well as methods of obtaining and processing
well casing using tubing, as well as methods of obtaining and processing information
about these processes using the operator console (Figure 7) and PC with the aim of further
modeling and forecasting the parameters of the extraction
extraction process.
process.
The bench is a collection of hardware, process control, monitoring tools, measuring
sensors, steel structures, and software.
The bench provides the following process functions:
- Ability to test extraction process operations in biofuel production in close to actual
well process conditions.
- Tests of the extraction process system at the specified physical parameters including
the pressure of the injected process liquid and the flow rate (or volume flow rate) of
the process liquid.
- Possibility of supercritical CO2 production by compression.
- Display of process progress information, i.e., process parameters and equipment states,
on the operator console.
- Remote control of technical devices from the operator console.

- Transfer of stand parameters to the database.
Sustainability 2022, 14, x FOR PEER
- REVIEW 13 of 28in case
Emergency disconnection of all technical devices and devices to ensure safety
of emergency situations.
Figure 7. Operator console for investigation of the extraction process in the well.
Figure 7. Operator console for investigation of the extraction process in the well.
The bench
3.3. Installation of isTest
a collection
Bench forofTesting
hardware, processExtraction
of Borehole control, monitoring
Processes tools, measuring
sensors, steel structures, and software.
The
Thestand
bench(Figure
provides8)the
consists of process
following four units: I is hydraulic station of the hydraulic
functions:
cylinder; II is well simulator; III is high-pressure hydraulic station; and IV is tank farm.
– Ability to test extraction process operations in biofuel production in close to actual
Pump station W-1 feeds a two-way hydraulic cylinder 2/1. Hydraulic cylinder 2/1 is
well process conditions.
mechanically
– Tests ofconnected to tubing
the extraction process 2/2
systemin casing 2/3.
at the specified physical parameters including
Thethehigh-pressure
pressure of thestation
injectedW-2 provides
process an injection
liquid and of process
the flow rate fluid
(or volume intorate)
flow tubing
of 2/2.
Tubingthe string
process2/2liquid.
has windows (through holes) that open in casing string 2/3 when
hydraulic
– cylinder
Possibility of2/1 moves together
supercritical with pipe
CO2 production by 2/2 to the right. The piston is installed on
compression.
tubing
– 2/2 (notofshown
Display processconventionally).
progress information, i.e., process parameters and equipment
Thestates,
benchon the with a 1 m3 4/1 flow tank and a 0.25 m3 4/2 drain tank.
operator console.
is equipped
–
Pumping Remote controlfrom
of liquid of technical devices
drain tank 4/2 from the operator
to flow console.
tank 4/1 is performed by drain pump
– Transfer of stand parameters to the database.
4/4. Tank 4/1 is equipped with a system of automatic heating of the process fluid 4/5
and– a circulation pump 4/3 for
Emergency disconnection ofmedium
all technicaltemperature
devices and averaging. The centrifugal
devices to ensure safety in casepump-
compressor used 4/8 to pump liquid or gas into casing 2/3.
of emergency situations.
All hydraulic systems are equipped with valves (positions “B” in the diagram of
Figure 8). Pressure
3.3. Installation in hydraulic
of Test systems
Bench for Testing is controlled
of Borehole byProcesses
Extraction pressure gauges. The volume of
liquid flow is controlled by an ultrasonic flowmeter 4/6. Tanks 4/1 and 4/2 are equipped
The stand (Figure 8) consists of four units: I is hydraulic station of the hydraulic cyl-
with level indication devices 4/7. Test bench monitoring devices and controls are reduced
inder; II is well simulator; III is high-pressure hydraulic station; and IV is tank farm.
to the operator panel.
Pump station W-1 feeds a two-way hydraulic cylinder 2/1. Hydraulic cylinder 2/1 is
Grades and
mechanically modelstooftubing
connected the main
2/2 inequipment
casing 2/3. used and equipment of the bench are
summarized in Table 4. station W-2 provides an injection of process fluid into tubing 2/2.
The high-pressure
Tubing string 2/2 has windows (through holes) that open in casing string 2/3 when
Sustainability 2022, 14, x FOR PEER REVIEW 15 of 28
Figure 8. Schematic
Figure 8. Schematic diagram
diagram of
of the
the borehole
borehole extraction
extraction test
test bench.
bench.
Table 4. Bench equipment specification.
Equipment Name Brand/Model

Hydraulic cylinder oil station IRS-5,5-50-16-2-19280
Hydraulic cylinder 140.80.900.001
High-pressure station ET Jet 280\21
Liquid level controller OVEN SAU-U.SHCH11
Liquid level gauge OVEN DS.P.3
Temperature controller OVEN TRM500-SHCH2.5
Temperature gauge (thermocouple) DTS 035-50.MV3.250
Compressor Pump UNIPUMP MH 1000C
Circulation pump OASIS CB 25\8
Drain pump Vikhr PN-370
Flowmeter Karat 520
Controlled bench parameters:

- Pressure levels of hydraulic supply systems of the hydraulic cylinder and high-
pressure station of process fluid supply;
- Operating medium temperature in the service tank;
- Liquid levels in the flow and drain tanks;
- Critical level of liquid in the service tank;
- Ambient temperature of the bench location at three measurement points;
- Process fluid flow volume by ultrasonic flowmeter;
- Availability of power supply on electric motors of pumps;
- Control of the linear stroke of the hydraulic cylinder rod.
The dispatching and monitoring of system operation parameters are organized on the
operator console.
3.4. Operation of the Stand

Process sequence on the bench:
(1) Feed to tubing 2/2;
(2) Supply of solvent (supercritical CO2 ) prepared in advance in consumption tank 4/1
to casing 2/3;
(3) Mixing of raw material and solvent by the movement of hydraulic cylinder 2/1 with
tubing 2/2 to the right. At the same time, pressure increases due to the piston installed
on the tubing;
(4) Maintenance and production of extract;
(5) Opening of valve B2/4 and overflow of extract into drain tank 4/2.
Heavy oil extraction efficiency was analyzed by assessing the viscosity of the residual
oil. The residual oil is the oil immobilized after the extraction process. CO2 dissolution was
carried out at a pressure of 10, 20, and 30 MPa. Residual oil sample viscosity was measured
at 30 ◦ C using a Brookfield rotary viscometer CAP-1000+.
To produce biofuels, the obtained extract is treated by thermal methods. In our case,
the process of low-temperature destruction was used.
3.5. Processing of the Hydrocarbon Component of the Obtained Extract

The process of low-temperature destruction (distillation) was carried out in reaction
equipment at a temperature of 550 ± 20 ◦ C and atmospheric pressure. The process of
destruction itself was divided into two stages:
1. The organic part of the extract is distilled to produce hydrocarbon gases and the raw
material is held in the reaction zone for 10, 20, and 30 min.
2. The production of hydrogen by the reaction of light hydrocarbons with a catalyst.
The duration of the process was determined by reducing the amount of hydrogen
produced. The process was carried out in the temperature range of 550 to 650 ◦ C.
equipment at a temperature of 550 ± 20 °C and atmospheric pressure. The process of de-
struction itself was divided into two stages:
1. The organic part of the extract is distilled to produce hydrocarbon gases and the raw
material is held in the reaction zone for 10, 20, and 30 min.
2. The production of hydrogen by the reaction of light hydrocarbons with a catalyst.
The duration of the process was determined by reducing the amount of hydrogen
produced. The process was carried out in the temperature range of 550 to 650 °C.
The experimental
Thebench for processing
experimental the processing
bench for hydrocarbonthecomponent of the
hydrocarbon obtainedof the obtained
component
extract is shown in Figure 9.
extract is shown in Figure 9.
Figure 9. Heavy oil components hydrocarbon distillation experimental bench diagram. 1—type 1
Figure 9. Heavy oil components hydrocarbon distillation experimental bench diagram. 1—type 1
pyrolysis reactor; 2, 6—pump; 3—refrigerator; 4—mud tank; 5—liquid product rectifier; 7—re-
pyrolysis reactor; 2, 6—pump; 3—refrigerator; 4—mud tank; 5—liquid product rectifier; 7—receiver;
ceiver; 8—gaseous product rectifier; 9—fan; 10—gas tank; and 11—type 2 pyrolysis reactor.
8—gaseous product rectifier; 9—fan; 10—gas tank; and 11—type 2 pyrolysis reactor.
The stand works Theasstand
follows:works as follows:
The obtained extract
The obtainedtoextract
is fed pyrolysis reactor
is fed 1 by means
to pyrolysis reactorof 1pump 2. The
by means ofheaters
pump 2. The heaters
provide the necessary amount of heat to start the destruction process. Thermocouples
provide the necessary amount of heat to start the destruction process. Thermocouples
monitor the temperature
monitor the parameters.
temperature Theparameters.
heat-insulating Thematerial retains heat
heat-insulating in theretains
material re- heat in the
actor, thereby reducing energy costs to maintain the pyrolysis process.
reactor, thereby reducing energy costs to maintain the pyrolysis process.
The released reaction products
The released are fed
reaction to heat are
products exchanger 3 to exchanger
fed to heat separate the liquid
3 to and the liquid and
separate
gaseous pyrolysis products.
gaseous Then,products.
pyrolysis they enterThen,
settling
theytank 4, where,
enter settlingbytank
means of pump
4, where, by 6,
means of pump
liquid products6,pass through
liquid products the hydrocyclone
pass through 5the and enter receiver
hydrocyclone 5 7and
for enter
temporary stor-
receiver 7 for temporary
age. storage.
In turn, the gaseous products,
In turn, the gaseousby means of the by
products, high-pressure
means of the fanhigh-pressure
9, pass through fancy-
9, pass through
clone 8 and enter the sampler
cyclone 10. the sampler 10.
8 and enter
In order to obtain hydrogen,
In order the hydrogen,
to obtain remainder the is sent to reactor
remainder 11 for
is sent toprocessing.
reactor 11 for processing.
The “Clarus 600” Thechromatograph was used to measure
“Clarus 600” chromatograph was used thetoconcentration
measure the of gaseous
concentration of gaseous
hydrocarbons in hydrocarbons in the gases
the gases generated generated
by the by the
distillation distillation of produced
of hydrocarbons hydrocarbonsby theproduced by the
extraction
extraction of heavy of heavy
petroleum petroleum
components components
formed formed
in the first in The
stage. the first stage. The chromatographic
chromatographic
condition is
condition is shown in Table 5. shown in Table 5.
Table 5. Chromatographic analysis conditions.

Table 5. Chromatographic analysis conditions.
Parameter Parameter Value Value

Analysis time Analysis time 180 min 180 min
Volume of sample
Volume of sample 10 mL 10 mL
Column length 100 m
Column length Carrier gas 100 m helium
Temperature: -
columns 250 ◦ C
detector 300 ◦ C
The catalytic pyrolysis method was used to decompose the gasified oil pyrolysis
product, methane. Proven effective in previous hydrogen production, high-percentage
nickel catalysts were used [111]; they are characterized by a high product yield efficiency
and low cost compared to catalysts containing noble metals.
The amount of hydrogen released was determined using the ”EMIS VIKHR 200”
(EMIS, Russia) vortex flowmeter.
and low cost compared to catalysts containing noble metals.
The amount of hydrogen released was determined using the ”EMIS VIKH
(EMIS, Russia) vortex flowmeter.
The lowest combustion heat of the resulting hydrocarbon gas mixtu
determined using a flow gas calorimeter Rhadox 7300 (“AMS Analysen-, Mess- u
temtechnik GmbH”, Germany).
The lowest combustion heat of the resulting hydrocarbon gas mixture was determined
4. Results
using a flow and Discussion
gas calorimeter Rhadox 7300 (“AMS Analysen-, Mess- und Systemtechnik
GmbH”, Dielheim, Germany).
The main result of the laboratory studies was confirmation that the developed
production
4. Results and technology
Discussion works under borehole conditions. In particular, a number
nological processes were
The main result of the successfully
laboratory studies tested in the laboratory
was confirmation facilitiesbiofuel
that the developed developed,
production technologyheavy
1. Supercritical works under borehole conditions.
oil extraction technologyIn particular,
adapteda to number of techno-
downhole condition
logical processes were successfully tested in the laboratory facilities developed, namely:
2. Thermal destruction technology of carbonated oil including mode paramete
1. Supercritical heavy oil extraction technology adapted to downhole conditions;
2.
opment (reaction times) to determine optimum conditions for the process;
Thermal destruction technology of carbonated oil including mode parameter develop-
3. Catalytic
ment pyrolysis
(reaction times) to technology for theconditions
determine optimum thermal for
degradation
the process; product of carbon
3. and hydrocarbon
Catalytic gases, determining
pyrolysis technology for the thermal different catalysts’
degradation product ofeffect on hydrogen
carbonated oil
and hydrocarbon gases, determining different catalysts’ effect on hydrogen yield.
Research results on these processes are explored consistently in this section.
Research results on these processes are explored consistently in this section.
The results of the residual oil viscosity change after exposure to CO2 at 10, 20
The results of the residual oil viscosity change after exposure to CO2 at 10, 20, and
MPa
30 MPacompared
compared totothe
the viscosity
viscosity of unexposed
of unexposed oil areinshown
oil are shown in Figure 10.
Figure 10.
Figure10.10.
Figure Change
Change in residual
in residual oil viscosity
oil viscosity after to
after exposure exposure
CO2 . to CO2.
According to the results (Figure 10), higher pressure increases the solubility of CO2 in
heavy According
oil. Significanttoresults
the results (Figure
are obtained 10), higher
at a pressure pressure
of 20 MPa. increases
However, the solubility
data obtained
in30heavy
at oil. Significant
MPa indicate that the trend results areoil
in residual obtained at aincreasing
viscosity with pressurepressure
of 20 is
MPa.
likelyHowev
to have a rapid limit, i.e., further pressure increases are ineffective, requiring
obtained at 30 MPa indicate that the trend in residual oil viscosity with increasing p additional
residual oil operations such as repeated extraction or additional heating. Dissolving CO2
is likely to have a rapid limit, i.e., further pressure increases are ineffective, re
increases the proportion of light hydrocarbons, mobilizing them and overcoming heavy
additional
oil’s residual
low mobility. oil operations
CO2 extraction such astorepeated
thus contributes extraction
raw materials’ or additional
manageability, in
Dissolving
particular, theirCO 2 increases Itthe
transportability. proportion
should of the
be noted that light hydrocarbons,
maximum mobilizing
working pressure of th
most tubing types
overcoming exceeds
heavy 25 MPa.
oil’s low mobility. CO2 extraction thus contributes to raw m
The results of the chromatographic analysis, in the first step, show that with an increase
in the residence time of the feedstock, from 10 to 20 min in the reaction chamber, the total
concentration of light hydrocarbons increases (Tables 6 and 7).
Table 6. Mass fraction of significant gaseous hydrocarbons (10 min).
Paraffins I-Paraffins Olefins Total

C1 17.65858 0.00000 0.00000 17.65858
C2 16.00151 0.00000 12.20181 28.20331
C3 27.25370 0.00000 0.000 27.25370
C4 2.36667 1.35820 13.42702 17.16389
C5 0.84303 0.78433 4.39634 6.19568
- - - - Σ = 96.47516

C1 19.88811 0.00000 0.00000 19.88811
C2 16.17640 0.00000 14.81408 30.99047
C3 25.69349 0.00000 0.00000 25.69349
C4 1.68399 1.32608 11.48839 14.50528
C5 0.56278 0.65271 3.23156 6.06642
- - - - Σ = 97.14377
A longer residence time of up to 30 min resulted in a decrease in the total concentration

of the gaseous fraction (Table 8).

C1 22.43875 0.00000 0.00000 22.43875
C2 16.50222 0.00000 14.02001 30.52223
C3 25.59214 0.00000 0.00000 25.59214
C4 1.19263 1.14706 10.62464 12.96433
C5 0.46900 0.51640 2.77713 5.34485
- - - - Σ = 96.8623
This can be explained by the conversion of minor organic products to significant ones
by chemical interaction at a given temperature (recorded by chromatographic analysis) as
well as losses.
The main components of the gas fraction were methane (CH4 ), ethylene (C2 H4 ), ethane
(C2 H6 ), propane (C3 H8 ), and butylene (C4 H8 ). In the entire range of holding time, only
their percentage changed (Figure 11).
Thus, a suitable holding time was about 20 min (ranging from 20 to 30 min). At the
same time, it should be understood that increased residence time leads to increased energy
consumption, which can affect the efficiency of the process, thereby spending more energy
than is obtained. At the same time, the concentration of the remaining hydrocarbons was
below 0.5%, or traces were observed.
In addition to the formation of gaseous products, liquid hydrocarbons and a solid
residue are also formed. The liquid fraction consisted of saturated, unsaturated, cyclic,
and aromatic hydrocarbons. In turn, the solid fraction consisted of coke; the combustion
of which produced ash. The present paper did not examine the liquid and solid fractions,
but only determined their quantitative distribution. Therefore, the distribution of fractions
during distillation was as follows: 60%—liquid, 20%—gaseous, and 20%—solid, with an
error of ±2%.
In addition to the quantitative characterization of the formed light hydrocarbons,
a qualitative assessment of the gaseous pyrolysis products was carried out. For this
purpose, the heat of combustion of the gas and the mixture was determined. The kinetics
of combustion heat change for pyrolysis gaseous products at 550 ◦ C is shown in Figure 12.
Sustainability 2022,
Sustainability 2022, 14,
14, 13083
x FOR PEER REVIEW 20
18of 28
of 25
Figure 11.
Figure 11. Chromatogram of the
Chromatogram of the gas
gas mixture
mixture from
from an
an extract
extract sample
sample (holding
(holding time
time 30
30 min).
min).
Thus, a suitable holding time was about 20 min (ranging from 20 to 30 min). At the
same time, it should be understood that increased residence time leads to increased en-
ergy consumption, which can affect the efficiency of the process, thereby spending more
energy than is obtained. At the same time, the concentration of the remaining hydrocar-
bons was below 0.5%, or traces were observed.
In addition to the formation of gaseous products, liquid hydrocarbons and a solid
residue are also formed. The liquid fraction consisted of saturated, unsaturated, cyclic,
during distillation was as follows: 60%—liquid, 20%—gaseous, and 20%—solid, with an
error of ±2%.
In addition to the quantitative characterization of the formed light hydrocarbons, a
qualitative assessment of the gaseous pyrolysis products was carried out. For this
purpose, the heat of combustion of the gas and the mixture was determined. The kinetics
of combustion heat change for pyrolysis gaseous products at 550 °C is shown in Figure
12.
Figure 12.
Figure 12. Kinetics
Kinetics of
of combustion
combustion heat
heat change
change for
for pyrolysis
pyrolysis gaseous
gaseous products
productsat 550◦°C.
at550 C.
As
As aa result
result of
of the
the calorimetric
calorimetric analysis,
analysis, itit was
was found
found that
that the
the lowest
lowest combustion
combustion heatheat
of
of the
the resulting
resulting gas
gas mixture reaches its maximum value at around 20 min (Figure 12).
Further
Further holding
holding time
time leads
leads to
to aa gradual
gradual reduction
reduction in in the
the combustion
combustion heatheat value,
value, i.e.,
i.e., the
the
calorific gas value is reduced. This phenomenon can be explained by
calorific gas value is reduced. This phenomenon can be explained by a deeper breakdown a deeper breakdown
of
of hydrocarbons
hydrocarbons and and anan increased
increased yield
yield ofof low-molecular-weight
low-molecular-weight gaseousgaseous products.
products. TheThe
combustion
combustion heatheat measurement
measurement error was ±
errorwas 1.52%.
±1.52%.
As
As mentioned
mentionedabove,above,ininthe
thesecond
secondstep,
step,light hydrocarbons
light hydrocarbons areare
converted to hydrogen
converted to hydro-
by reacting with the catalyst. To do this, the distillation products were
gen by reacting with the catalyst. To do this, the distillation products were dischargeddischarged from the
reaction apparatus, the catalyst was charged, and by running the gas
from the reaction apparatus, the catalyst was charged, and by running the gas fraction fraction (methane)
in the presence
(methane) in theofpresence
a catalyst,ofaaprocess
catalyst,ofahydrogen
process offormation
hydrogentook place and
formation tookthe carbon
place and
nanomaterials were formed.
the carbon nanomaterials were formed.
The
The results
results and
and catalysts
catalysts used
used are
are shown
shown in inTable
Table9.9.
Table 9. Results and catalysts used.
Table 9. Results and catalysts used.
Composition of Reaction Hydrogen Output,
№ Catalyst Composition, wt% Reaction ◦C
Initial HydrocarbonsTemperature, L/h
Composition of In- Hydrogen Out-
№1 Catalyst Composition,
90% Ni + 10% Al2 O3 wt% CH Tempera-
550 ± 20 ◦ C 56
itial Hydrocarbons
4 put, L/h
2 90% Ni + 10% Al2 O3 CH4 650 ± 20 ◦ C
ture, °C 111
70% Ni + 20% Cu + 10% ◦C
13 90% Ni + 10% Al2O3
Al2 O
CH 4 CH4 550 ± 20 °С
550 ± 20 56
44
3
24 90%
70% Ni +Ni
20%+ Cu
10% Al2O3
+ 10%
CH4
CH 4 650 ± 20
◦
650 ± 20 C
°С 111
114
Al2 O3
3 70% Ni + 20% Cu + 10% Al2O3 CH4 550 ± 20
◦ °С 44
5 70% Ni + 20% Cu + 10% SiO2 CH4 550 ± 20 C 90
46 70% Ni++20%
70% Ni 20%CuCu + 10%
+ 10% SiO2 Al2O3 CH4 CH4 650
650 ± 20
± 20 ◦ C °С 114
118
5 70% Ni + 20% Cu + 10% SiO2 CH4 550 ± 20 °С 90
6 The70% Ni + 20%
obtained Cu + 10%
hydrogen SiO
yield CH4 ranged from
of2 the test extract 650 ± 44
20 to
°С118 L/h depending
118
on the catalyst (Table 9). As can be seen from the results, with an increase in the process
temperature, there was a roughly twofold increase in the hydrogen yield. This is explained,
as in the previous case, by deeper conversion of raw materials. Additionally, with an
increase in the reaction temperature, an increase in the residual methane content of the
reaction products was observed. Furthermore, the increase in temperature affects the
effective operation time of the catalyst, leading to its faster deactivation. Further adsorption
of methane can be carried out on carbon plates in order to separate the gas fraction.
According to Table 9, the nickel-based catalyst on aluminum oxide had the lowest
hydrogen yield. The low efficiency of the monometallic catalyst in gaseous hydrocarbon
decomposition can be explained by its rapid deactivation. It can be due to the catalyst’s low
active metal content, and the use of aluminum oxide as a carrier which, in its turn, has weak
acidic properties and can itself take part in the chemical reaction leading to by-product
formation. The nickel catalyst with silicon dioxide has the highest hydrogen production
efficiency. It contains a larger amount of active metal and uses silicon dioxide as a carrier.
Silicon dioxide, compared to aluminum oxide, has a higher specific surface area and is
characterized by greater inertness towards the active metal deposited thereon.
5. Conclusions
1. The sustainability of the Eastern Siberian Arctic is highly dependent on the region’s
energy sector processes. The remoteness and climatic conditions of the region make
it unique and limit its sustainable development, significantly narrowing the scope
for renewable energy in particular. The deep and expanding oil and gas industry
poses new risks, challenges, and opportunities for the region’s development. A large
amount of oil industry waste raised an acute environmental issue in the region. In
the future, due to the need to ensure special environmental safety measures, this
can negatively affect the economic and political development of Russia and beyond.
These conditions require the development of new unique solutions equal with the
Paris Climate Agreement and other global regulatory documents.
2. One of the solutions was given to us by the fact that Russia is the leader in the
emissions of flare gases, a significant part of which are hydrocarbon production and
processing enterprises. We saw relevance in the use and disposal of these gases, as
industrial waste, with a concurrent decrease in the carbon footprint. In particular, flare
gases can be used after processing as a solvent for another industrial waste, heavy oil,
for its recovery and subsequent creation of biofuel compositions based on it, which is
also relevant for oil sludge.
3. According to the review results of potential raw materials for biofuel production
in the Eastern Siberian Arctic, apart from the petroleum industry waste, there is
yedoma whose energy potential is yet to be developed. The review of petroleum
stimulation technologies, particularly VAPEX, confirms the feasibility and indicates
how to effectively manage heavy oil or oil sludge by means of CO2 extraction.
4. Well extraction technology has been proposed for biofuel production by extracting
heavy oil or oil sludge with supercritical carbon dioxide derived from flare gases. A
conceptual process diagram of the downhole extractor for the production of biofuels
on an industrial scale has been developed. The main stages of biofuel production
technology adapted to downhole conditions are flare gas capturing; carbon dioxide
recovery from flare gases; bringing carbon dioxide to a supercritical state in the well;
the carbon dioxide extraction of heavy oil or oil sludge in the well; and thermal
decomposition stages of carbonated oil by pyrolysis methods.
5. Tests of the biofuel production technology adapted to downhole conditions were
successfully carried out on the presented specially designed laboratory benches for
three successive technological processes of the technology: CO2 heavy oil extraction;
thermal decomposition of carbonated oil by low-temperature pyrolysis methods;
and thermal decomposition of the low-temperature pyrolysis product using the gas
fraction by catalytic pyrolysis method.
6. Assessing the effectiveness of carbon dioxide extraction of the Vankor field heavy
oil in adapted field conditions was evaluated by analyzing the dynamic residual
oil viscosity at gas pressures of 10, 20, and 30 MPa. The result shows that CO2
actively mobilizes heavy oil and can act as a useful tool for feedstock management.
Carbon dioxide’s solvent efficiency growth peaks at about 20 MPa, after which, it
rapidly drops.
7. The qualitative and quantitative evaluations of formed light hydrocarbons in carbon-
ated oil low-temperature pyrolysis were performed using calorimetric and chromato-
graphic analysis methods. The present paper did not examine the liquid and solid
fractions, but only determined their quantitative distribution. Therefore, the distribu-
tion of fractions during distillation was as follows: 60%—liquid, 20%—gaseous, and
20%—solid. The main components of the gas fraction were methane, ethylene, ethane,
propane, and butylene. Thus, a suitable holding time was about 20 min (ranging
from 20 to 30 min). At the same time, it should be noted that increased residence
time leads to increased energy consumption, which can affect the efficiency of the
process, thereby spending more energy than is obtained. The lowest combustion heat
of gaseous pyrolysis products achieves its maximum value around 20 min. Further
holding time leads to a lower calorific gas value.
8. The catalytic pyrolysis of gaseous products (methane) obtained as a result of low-
temperature pyrolysis was carried out using nickel catalysts of different compositions
at temperatures between 550 and 650 ◦ C. Aluminum oxide and silicon dioxide were
used as the catalyst carriers and the results were assessed by hydrogen yield. The
obtained hydrogen yield of the test extract ranged from 44 to 118 L/h. With an
increase in the process temperature, there was a roughly twofold increase in the
hydrogen yield. The nickel catalyst with silicon dioxide had the highest hydrogen
production efficiency.
9. The proposed technology will allow for the extraction of biofuels on an industrial
scale with application in liquidated and injection wells, solving problems of envi-
ronmental safety, and involving waste of the oil and gas industry in the process of
biofuel production. This novel project requires further research and, in particular,
an assessment of the economic costs of its implementation, taking into account both
market and non-market ecosystem benefits.
Author Contributions: Conceptualization, K.A.B., O.A.K. and V.V.B.; methodology, K.A.B., O.A.K.,
V.V.B., V.S.T. and V.V.K.; validation, K.A.B., O.A.K. and V.V.B.; formal analysis, K.A.B., O.A.K.
and S.O.K.; investigation, K.A.B., O.A.K., S.O.K. and V.S.T.; resources, K.A.B., O.A.K., S.O.K. and
V.V.K.; data curation, R.B.S., V.S.T. and V.V.B.; writing—original draft preparation, K.A.B., O.A.K.
and E.V.T.; writing—review and editing, K.A.B., O.A.K., R.B.S. and E.V.T.; visualization, K.A.B.,
O.A.K., V.V.K. and S.O.K.; supervision, K.A.B., V.V.B. and V.S.T.; project administration, V.V.B. and
K.A.B.; and funding acquisition, V.V.B. All authors have read and agreed to the published version of
the manuscript.
Funding: The studies were carried out according to the state assignment from the Ministry of Science
and Higher Education of the Russian Federation for the project “Development of a set of scientific and
technical solutions in the field of creating biofuels and optimal biofuel compositions, providing the
possibility of transforming consumed types of energy in accordance with trends in energy efficiency,
reducing the carbon footprint of products and using alternative fuels to fossil fuels” (Contract FSRZ-
2021-0012), in the scientific laboratory of biofuel compositions of the Siberian Federal University,
created as part of the activities of the Scientific and Educational Center “Yenisei Siberia”.
Institutional Review Board Statement: Not applicable.
Informed Consent Statement: Not applicable.
Data Availability Statement: Not applicable.
Conflicts of Interest: The authors declare no conflict of interest.
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sustainability

1 Department of Technological Machines and Equipment of Oil and Gas Complex,

Copyright: © 2022 by the authors.

Sustainability 2022, 14, 13083. https://doi.org/10.3390/su142013083 https://www.mdpi.com/journal/sustainability

energy availability, and environmental sustainability. Economics, politics, and environ-

Table 1. Gas flaring data [15].

Gas Gas Flaring Volume

Figure 1. Supercritical extraction flow diagram. 1—supercritical CO2 ; 2—co-solvent; 3—proportioning

Construction Design Material

Figure 3. Main raw materials

1. The energy 1. potential of biological

Table 3. Main properties of crude oil.

Table 3. Main properties of crude oil.

3.2. Purpose and Functions of Borehole Extraction Test Bench

- Remote control of technical devices from the operator console.

Sustainability 2022, 14, 13083 13 of 25

Table 4. Bench equipment specification.

Equipment Name Brand/Model

Controlled bench parameters:

3.4. Operation of the Stand

3.5. Processing of the Hydrocarbon Component of the Obtained Extract

Table 5. Chromatographic analysis conditions.

Parameter Parameter Value Value

Table 6. Mass fraction of significant gaseous hydrocarbons (10 min).

Paraffins I-Paraffins Olefins Total

Table 7. Mass fraction of significant gaseous hydrocarbons (20 min).

Paraffins I-Paraffins Olefins Total

A longer residence time of up to 30 min resulted in a decrease in the total concentration

Table 8. Mass fraction of significant gaseous hydrocarbons (30 min).

Paraffins I-Paraffins Olefins Total

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