Blockchain Technology in the Oil and Gas Industry: A Review of Applications, Opportunities, Challenges, and Risks

Abstract

Blockchain technology has been developed for more than ten years and has become a trend in various industries. As the oil and gas industry is gradually shifting toward intelligence and digitalization, many large oil and gas companies have been working on blockchain technology in the past two years because it can significantly improve the management level, efficiency and data security of the oil and gas industry. This paper aims to let more people in the oil and gas industry understand the blockchain and lead more thinking about how to apply the blockchain technology. To the best of author’s knowledge, this is one of the earliest papers on the review of the blockchain system in the oil and gas industry. This paper first presents the relevant theories and core technologies of blockchain, and then describes how the blockchain is applied to the oil and gas industry from four aspects: trading, management and decision making, supervision and cyber security. Finally, the application status, the understanding level of the blockchain in the oil and gas industry, opportunities, challenges, risks and development trends are analyzed. The main conclusions are as follows: (1) At present, Europe and Asia have the fastest pace of developing the application of blockchain in oil and gas industry, but there are still few oil and gas blockchain projects in operation or testing worldwide. (2) Nowadays, the understanding of blockchain in the oil and gas industry is not sufficiently enough, the application is still in the experimental stage, and the investment is not enough. (3) Blockchain can bring many opportunities to the oil and gas industry, such as reducing transaction costs and improving transparency and efficiency. However, since it is still in the early stage of the application, there are still many challenges, primarily technological, regulatory and system transformation. (4) The development of blockchains in the oil and gas industry will move towards hybrid blockchain architecture, multi-technology combination, cross-chain, hybrid consensus mechanisms, and more interdisciplinary professionals.

Full text

Received March 2, 2019, accepted March 17, 2019, date of publication March 27, 2019, date of current version April 11, 2019.
Digital Object Identifier 10.1109/ACCESS.2019.2907695
Blockchain Technology in the Oil and Gas
Industry: A Review of Applications,
Opportunities, Challenges, and Risks
HONGFANG LU 1,2, KUN HUANG2, MOHAMMADAMIN AZIMI1, AND LIJUN GUO3
1Trenchless Technology Center, Louisiana Tech University, Ruston, LA 71270, USA
2State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China
3China Center for Information Industry Development, Beijing 100048, China
Corresponding author: Hongfang Lu (luhongfang_sci@126.com)
This work was supported by the China Scholarship Council under Grant 201708030006.
ABSTRACT Blockchain technology has been developed for more than ten years and has become a trend
in various industries. As the oil and gas industry is gradually shifting toward intelligence and digitalization,
many large oil and gas companies were working on blockchain technology in the past two years because of
it can significantly improve the management level, efficiency, and data security of the oil and gas industry.
This paper aims to let more people in the oil and gas industry understand the blockchain and lead more
thinking about how to apply the blockchain technology. To the best of our knowledge, this is one of the
earliest papers on the review of the blockchain system in the oil and gas industry. This paper first presents the
relevant theories and core technologies of the blockchain, and then describes how the blockchain is applied
to the oil and gas industry from four aspects: trading, management and decision making, supervision, and
cyber security. Finally, the application status, the understanding level of the blockchain in the oil and gas
industry, opportunities, challenges, and risks and development trends are analyzed. The main conclusions are
as follows: 1) at present, Europe and Asia have the fastest pace of developing the application of blockchain
in the oil and gas industry, but there are still few oil and gas blockchain projects in operation or testing
worldwide; 2) nowadays, the understanding of blockchain in the oil and gas industry is not sufficiently
enough, the application is still in the experimental stage, and the investment is not enough; and (3) blockchain
can bring many opportunities to the oil and gas industry, such as reducing transaction costs and improving
transparency and efficiency. However, since it is still in the early stage of the application, there are still
many challenges, primarily technological, and regulatory and system transformation. The development of
blockchains in the oil and gas industry will move toward hybrid blockchain architecture, multi-technology
combination, cross-chain, hybrid consensus mechanisms, and more interdisciplinary professionals.
INDEX TERMS Blockchain, oil and gas industry, smart contract, oil and gas trade, track equipment,
supervision.
I. INTRODUCTION
With the advancement of science and technology, the impor-
tance of oil and gas resources in promoting global eco-
nomic and social progress is increasing. According to the
‘‘BP Statistical Review of World Energy’’ released by BP in
June 2018 [1], oil and natural gas account for 57% of total
energy consumption (Fig.1). Moreover, global oil consump-
tion increased by 1.8%, exceeding the average growth rate
The associate editor coordinating the review of this manuscript and
approving it for publication was Tao Zhang.
of 1.2% for three consecutive years, while the consumption of
natural gas has increased by 96 billion cubic meters, reaching
the fastest growth rate after 2010. However, according to
‘‘BP Energy Outlook 2019 edition’’ [2], although the world
is vigorously promoting the development of new energy, oil
and gas will still occupy half of the world’s energy by 2040.
Besides, the report also pointed out that with the continuous
expansion of liquified natural gas (LNG) trade, LNG will
account for 15% of total natural gas demand in 2040. There-
fore, oil and natural gas will continue to dominate the global
energy market in the next 20-30 years.
41426
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FIGURE 1. Energy consumption in 2017 (unit: million tonnes oil
equivalent).
As oil and gas resources play an essential role in the energy
field, the technologies of the oil and gas industry have also
developed rapidly in recent years, such as intelligent drilling
technology, intelligent oil and gas fields, and marine digital
platforms [3], [4]. It can be seen that the oil and gas industry
is gradually developing towards the direction of intellectual-
ization, digitalization, and automation. However, its manage-
ment mode is relatively old, and it has the characteristics of
low efficiency, high cost, long period and high risk.
Oil and gas industry can be divided into three sections
according to the market division: upstream, midstream and
downstream. The upstream refers to the exploration and
development of oil and gas, the midstream refers to the
transportation of oil and gas, and the downstream refers to
the storage and sales [5]. The value chain of the oil and gas
industry is shown in Fig. 2. In different markets, there are still
many shortcomings in management [6], which are concluded
in Table 1.
FIGURE 2. The value chain of oil and gas industry.
Except for the various management issues listed in Table 1,
there are still other issues to be addressed. For example,
since the oil and gas industry is a huge system, it involves
multi-party transactions and trade, the paperwork and rec-
onciliations generated in each link are very cumbersome
and error-prone. In summary, the management issues of
the oil and gas industry mainly involve the following four
aspects:
TABLE 1. Management issues and consequence in different markets in
the oil and gas industry [6].
•A large amount of paperwork and reconciliation
work increases the monetary and time costs of the
transaction.
•The oil and gas industry has the characteristics of multi-
party investment and cooperation, and the risks of fraud,
error, and inefficiency in transactions are relatively
high.
•The third-party management costs in the oil and gas
trade are relatively high, the trade negotiation process
is inefficient, and the exchange of critical data is slow.
•Important data is at higher risks from cyber-attacks.
Based on the above problems, it is time for the oil and
gas industry to change its management mode. A relatively
new technology called blockchain has been found to have
great potential for use in the oil and gas industry. In 2008,
the emergence of Bitcoin triggered a boom in the develop-
ment of blockchain technology. In this decade, the devel-
opment of blockchain technology has been through three
stages: the blockchain 1.0 era represented by Bitcoin, the
blockchain 2.0 era marked by Ethereum and smart con-
tracts, the blockchain 3.0 era for application in the social
field [7]. Currently, blockchain technology has been applied
in many industries. However, in the beginning, the oil and gas
industry has been holding a wait-and-see attitude and rarely
involved. Until 2017, British Petroleum (BP) began testing
the blockchain project, and the oil and gas industry took the
first step in applying blockchain technology. The rest of paper
is organized as follows:
Section II describes the motivation and contributions of
this paper. Section III presents the key technologies for
blockchain. Section IV describes the potential application
scenarios of blockchain technology in the oil and gas indus-
try. Section V discusses the application status, opportunities,
challenges and risks of blockchain technology in the oil and
gas industry. Section VI summarizes the main conclusions
drawn from this paper.
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II. MOTIVATION AND CONTRIBUTION
A. MOTIVATION
According to Deloitte’s 2018 global blockchain survey [8],
61% of respondents in the oil and gas industry believe that
‘‘blockchain is only a monetary database and a financial
service application’’, and only 15% of respondents have been
applied blockchain to practice. The blockchain has been
developed for ten years, but the oil and gas industry has only
begun to implement and explore in the past two years, indicat-
ing that the current understanding of blockchain technology
in the oil and gas industry is still in its infancy. Therefore,
the motivation of this paper is to let more oil and gas industry
people understand the blockchain and understand the benefits
and applicable occasions of the blockchain, and to promote
the development of blockchain technology in the oil and gas
industry.
B. CONTRIBUTIONS
In the following, the contributions of this paper are
concluded as:
(1) Firstly, the core technologies and characteristics of
the blockchain technology are systematically discussed,
including explaining what the blockchain is, how the
blockchain works, the classification of the blockchain, and
the blockchain security techniques. The primary purpose of
this section is to let people understand the basic principles of
the blockchain.
(2) Second, this paper introduces the idea of blockchain
technology to the oil and gas industry. The application field
is divided into four parts: trading, management and decision
making, supervision, and cyber security. The content of this
section will let people know how the blockchain will actually
be applied to the oil and gas industry, and demonstrate the
advantages of blockchain technology via examples.
(3) Finally, this paper analyzes the application status of
blockchain technology in the oil and gas industry, analyzes
the opportunities, challenges, and risks that may be encoun-
tered, and analyzes the development trends.
III. THEORIES OF BLOCKCHAIN
This section introduces the basic theories and techniques
related to blockchain. The basic theories include the
concept of blockchain (Section III A), the characteris-
tics (Section III B) and classification (Section III C) of
blockchain. Related techniques include consensus algo-
rithm (Section III D), cryptography and security technology
(Section III E), data record model (Section III F) and dis-
tributed storage system (Section III G).
A. THE CONCEPT OF BLOCKCHAIN
The explanations of blockchain in different works of litera-
ture are not entirely uniform. Essentially, blockchain is a kind
of mode to realize and manage transaction processing through
transparent and trustworthy rules to construct non-forgeable,
non-tampering and traceable blockchain data structure in
peer-to-peer (P2P) network environment [9]–[13]. It is a new
application mode combining computer technologies such as
distributed data storage, consensus mechanisms, peer-to-peer
transmission, and encryption algorithms. The biggest inno-
vation of blockchain technology is that transactions are no
longer stored in the central database, but are distributed to all
participants.
FIGURE 3. Transaction model. (a) Traditional model. (b) Blockchain model.
Peer-to-peer means that the computers in each node in the
network have equal status, each node has the same network
power, and there is no centralized server [14]–[16]. All nodes
share some resources or information through specific pro-
tocols. Fig. 3 shows the traditional transaction model and
blockchain transaction model [16]. In the traditional trans-
action model, transactions depend on the central authority,
and transaction data is mainly stored by the central authority.
In the blockchain transaction model, transactions can be con-
ducted directly between the two parties without third party
intervention, and all transaction data are stored in the dis-
tributed blockchain, and all relevant information is stored in
each participant. Therefore, the blockchain can well eliminate
the influence of third parties. However, if the central authority
is removed, then how to verify the transaction and ensure
the integrity of the ledger becomes a challenge. It requires
a suitable verification process, a process called consensus
algorithm, which will be mentioned in Section III D.
FIGURE 4. The blockchain process [16].
As shown in Fig. 4, if a person agrees to complete a trans-
action with another person (Step 1), they use the transaction-
related data as a variable and combine with other transac-
tions in the same period to form a new data block (Step 2).
Each transaction is encrypted and distributed to multiple
computers in a P2P manner. Network members use algo-
rithms to validate transactions stored on individual comput-
ers. The algorithm appends a unique hash value to each block.
If any information related to the transaction is tampered with,
the correct hash value cannot be generated, and an error is
reported (Step 3). When this block is successfully verified,
it is combined with the block that was previously verified
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to form a blockchain (Step 4). Finally, both parties confirm
the transaction, which means the transaction is successful
(Step 5) [16], [17].
B. KEY CHARACTERISTICS OF BLOCKCHAIN
Blockchain technology has six main characteristics, includ-
ing: decentralization, immutability, transparency, efficiency,
security and anonymity [18].
1) DECENTRALIZATION
Decentralization is the most essential feature of the
blockchain-based system, which means that the blockchain-
based system no longer depends on the central processing
node, which realizes the distributed recording, storage, and
update of data [19]. The status of each node is the same,
and the data blocks are maintained by the nodes with the
maintenance function in the entire system. Stopping any node
will not affect the overall operation of the system.
2) IMMUTABILITY
Information cannot be changed after the it is verified and
added to the blockchain. For example, in the Bitcoin’s
blockchain system, unless more than 51% of the nodes in the
control system can be simultaneously controlled, the modi-
fication is invalid, so the data stability and reliability of the
block chain are extremely high [10], [20].
3) TRANSPARENCY
Transparency is the basis for blockchain to be trusted because
data record and update are transparent to the nodes of the
entire network. Therefore, network-wide nodes with high
transparency can be used to review, track data records, and
track operations [21], [22].
4) EFFICIENCY
The blockchain technology makes the system more trans-
parent by distributing database records to users in the sys-
tem, so it is more efficient in terms of risk, cost, and
so on [23], [24].
5) SECURITY
If a centralized network is attacked, it is likely to affect the
whole system. However, blockchain-based system has the
characteristics of decentralization. If a node is attacked, it
will not destroy the security of the entire system. Moreover,
blockchains use public key infrastructure to prevent mali-
cious behavior from changing data, thus providing better
security [19].
6) ANONYMITY
In the blockchain systems, both parties can make the transac-
tion anonymous because the program rules in the blockchain
can automatically determine whether the exchange activities
between nodes are valid [25].
C. CLASSIFICATION OF BLOCKCHAIN SYSTEMS
The blockchain-based system can be divided into two cate-
gories according to the openness: permissioned blockchain
and permissionless blockchain (public blockchain) [26], [27].
The permissioned blockchain can be further divided into the
private blockchain and consortium blockchain.
1) PRIVATE BLOCKCHAIN
The private blockchain refers to a blockchain whose write
permission is only controlled by an organization or an indi-
vidual, and the read permission may be open to the outside.
The private blockchain system is the most closed and is
limited to use by enterprises, state agencies or individuals.
It does not fully solve the trust problem, but it can improve
auditability [9].
2) PUBLIC BLOCKCHAIN
The public blockchain refers to a blockchain that can be
read by anyone in the world, can send transactions and can
be validated effectively, and anyone can participate in the
consensus process. The public blockchain is the ultimate
embodiment of decentralization [28].
3) CONSORTIUM BLOCKCHAIN
The consortium blockchain refers to a blockchain that is
restricted to the participation of the members of the con-
sortium. The read and write permissions on the blockchain
and the participation of the accounting rights are determined
according to the consortium rules. Each participant in the
consortium blockchain does not have to worry about where
their data exists. The data they generate can only be seen
by themselves or by authorized people. In this way, it will
solve data privacy and security issues and decentralize. It is a
combination of public and private blockchains [29].
Table 2 summarizes the characteristics of the three kinds
of blockchains [9], [30], [31]. When selecting the blockchain
type, factors such as database requirements and multi-party
writing should be considered. A white paper published
in 2018 by China Academy of Information and Communi-
cations Technology and Trusted Blockchain Initiatives have
a flow chart for choosing blockchain types [32], as shown
in Fig. 5.
D. CONSENSUS ALGORITHM
The verification process is to achieve a consensus on the con-
tent of the distributed ledger. It is a process of decentralization
and automation. It can be said that the consensus algorithm is
one of the most critical technologies in the blockchain. The
blockchain consensus algorithm can be classified according
to fault tolerance type and consistency degree. In order to
facilitate the description of the core mechanism of the con-
sensus algorithm, Yuan et al. [33] classified it according to
the leader election strategy in 2018. Their classification and
characteristics are shown in Table 3.
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TABLE 2. Comparison of three blockchains.
FIGURE 5. Flow chart for selecting blockchain type [32].
TABLE 3. Consensus algorithm type and characteristics [33].
This paper presents six commonly used consensus algo-
rithms, of which proof of work (PoW) and proof of
stake (PoS) are the most used. Table 4 lists the charac-
teristics of these six consensus algorithms [33]. There are
many consensus algorithms and their extension algorithms.
Appendix A lists the emergence time, basic algorithm, and
Byzantine fault tolerance performance of 32 mainstream con-
sensus algorithms.
1) PROOF OF WORK (PoW)
The proof of work (PoW) can be simply understood as a proof
to confirm a certain amount of work done. However, the orig-
inal intention of the algorithm is to solve the spam problem.
PoW is a consensus mechanism adopted by Bitcoin, Litecoin,
etc. The idea of PoW algorithm is to let the initiator consume a
certain amount of computing power and economic resources,
thereby greatly increasing the overhead required for the attack
and avoiding service abuse and attacks. Apparently, in order
to increase the probability of obtaining reward, it is necessary
to increase the computing power of nodes (miners) to solve
a complex but easy-to-verify SHA256 mathematical prob-
lem. Under this mutual stimulation, the whole system will
continue to increase the computing power. On the one hand,
it increases the difficulty of attack of the whole system, on the
other hand, it wastes many computing resources [34]–[36].
2) PROOF OF STAKE (PoS)
PoS is a consensus algorithm that is commonly applied to
public blockchains and depends on the economic rights of the
verifier in the network [34], [37], [38]. In a blockchain, a set
of verifiers alternates and votes for the next block, and each
verifier’s voting weight depends on the size of its guaranteed
amount (i.e., stake). In the PoS algorithm, the blockchain
tracks a set of verifiers, and anyone who holds the cryptocur-
rency of the blockchain can become a verifier by sending a
cryptocurrency lock as a margin. Subsequently, the process
of creating and recognizing new blocks can be done by all
current verifiers. Significant advantages of the PoS algorithm
include higher security and higher energy efficiency.
3) DELEGATED PROOF OF STAKE (DPoS)
DPoS is a consensus algorithm based on the development of
PoW and PoS. In this algorithm, each holder can vote, thereby
generating a certain number of nodes or pools, and their
rights are completely equal, and the holder can change these
representatives at any time by voting. It manages the entire
chain operation in a low-cost way, thus solving the problem of
a large amount of energy consumption of the PoW during the
mining process. At the same time, the more ‘‘decentralized’’
management method distributes the decision-making power
of the blockchain network operation to each node of the whole
network, and can also avoid the problem of uneven trust in the
PoS algorithm [39].
4) PRACTICAL BYZANTINE FAULT TOLERANCE (PBFT)
PBFT algorithm was put forward by Miguel Castro and
Barbara Liskov in 1999. It solves the problem of ineffi-
ciency of the original Byzantine fault-tolerant algorithm and
reduces the complexity of the algorithm from exponential
level to polynomial level, which makes Byzantine fault-
tolerant algorithm feasible in practical system applications.
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TABLE 4. The characteristics of the six consensus algorithms [43].
In PBFT algorithm, security is guaranteed by all nodes of the
system. The consensus is mainly determined by three votes
between nodes. One node represents one vote and achieves
consensus among nodes in a majority rule. PBFT algorithm
allows no more than 1/3 of the nodes to fail, that is, in the
environment of (3f+1) nodes, if there are (2f+1) normal
nodes, the whole system can operate normally [39], [40].
5) PROOF OF ELAPSED TIME (PoET)
PoET is a lottery protocol built by Intel in a trusted exe-
cution environment. The core is CPU hardware that sup-
ports Intel SGX (Software Guard Extensions) technology.
It randomly generates some delays in a controlled security
environment, and the CPU proves the reliability of the delay
from the hardware level. Whoever has the lowest latency
will receive accounting rights. In this way, the only way
to increase accounting rights is to increase the number of
CPUs. At the same time, the increased CPU will increase the
resources of the entire system, thus achieving a proportional
relationship between the accounting rights and the provided
resources [41].
6) TENDERMINT
The Tendermint algorithm is optimized for the traditional
PBFT algorithm and requires only two rounds of voting to
reach a consensus: pre-vote and pre-commit. In the same
round of commit, only more than two-thirds of validators pre-
commit the same block can submit the block to the chain.
Sometimes the validator may fail to submit a block because
the current proposer is offline or the network is slow. Tender-
mint allows them to verify that a validator should be skipped.
Before the next round of voting, the validator waits for a
short time to receive a complete proposal block from the
proposer. This dependence on timeouts makes Tendermint a
weak synchronization protocol rather than an asynchronous
one. However, the rest of the protocol is asynchronous, and
only when more than two-thirds of the set of validators is
received, will the validator take the next step. One reason
Tendermint can simplify is that it uses the same mechanism
to submit a block and skip directly into the next round [42].
E. CRYPTOGRAPHY AND SECURITY TECHNOLOGY
Cryptography is also one of the most core technologies in
the blockchain. It is mainly divided into two categories: hash
algorithm and asymmetric encryption algorithm.
1) HASH ALGORITHM
Hash algorithm is the most commonly used cryptographic
algorithm in the blockchain. In blockchain, hash algorithm
is mainly used for data integrity, data encryption, proof of
work in consensus computing, the link between blocks and
so on. It can compress messages of arbitrary length into
binary strings of fixed length in a limited and reasonable
time, and output hash value. It is a one-way cryptosystem,
that is, an irreversible mapping from plaintext to cipher-
text (only encryption process, no decryption process) [44].
Hash function has the characteristics of unidirectionality
(forward speed is fast, and the reverse is difficult), collision
resistant, puzzle friendliness (there is no convenient method
to produce a hash value to meet individual requirements).
Several hash functions currently used in the blockchain
include MD5, SHA1, SHA256, and SM3, and their charac-
teristics are shown in Table 5.
TABLE 5. Commonly used hash functions and features.
Since the blockchain records complete data information
and cannot delete or modify the block record, the block will
continue to increase and will occupy a large amount of storage
space. Therefore, the way to use the Merkle Tree to store
transaction hashes is proposed. The Merkle tree is similar
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TABLE 6. Commonly used asymmetric encryption algorithms and features [51].
to the tree structure in the data structure, mainly binary tree
and multi-fork tree. Each transaction record corresponds to a
hash value and corresponds to the leaf node of the Merkle
Tree [49]. The two leaf nodes are paired again with hash
calculation. Recursively until the last hash value is stored
in the block as the Merkle root. Therefore, you can reclaim
hard disk space by simply removing old transactions from
Merkle Tree.
2) ASYMMETRIC ENCRYPTION ALGORITHM
Asymmetric encryption algorithm refers to the use of public
and private keys to encrypt and decrypt data storage and
transmission [50]. The public key can be made public for
the sender to encrypt the information to be sent, and the
private keycan be used for the receiver to decrypt the received
encrypted content. Because of the dependence between the
public key and the private key, only the authorized user
can decrypt the information. Public-private key pairs take a
long time to compute and are mainly used to encrypt fewer
data. The commonly used asymmetric encryption algorithms
are Rivest-Shamir-Adleman (RSA), Elliptic-curve cryptog-
raphy (ECC) and SM2, and their characteristics are shown
in Table 6.
F. DATA R ECORD MODEL
There are two main ways to record data in the blockchain: the
Unspent Transaction Output (UTXO) model and the Account
model.
1) UTXO
UTXO is a core concept in the generation and verification
of bitcoin transactions. The transaction constitutes a chain
structure. All legal bitcoin transactions can be traced back to
the output of one or more forward transactions. The source
of these chains is the mining reward, and the end is the
current unspent transaction output. All unspent output is the
UTXO of the entire Bitcoin network [54]. The calculation
of the model is off-chain, reducing the burden on the chain.
Besides, the UTXO model is stateless and more accessible
to handle concurrently. However, it cannot implement some
complicated logic and the programmability is poor.
2) ACCOUNT MODEL
The Account model keeps the balance of each account
global [55]. The state of the chain is generally agreed in the
block in the form of StateRoot and ReceiptRoot [56]. The
transaction is only the event itself, does not contain results,
and the consensus of the transaction and the consensus of the
state can be isolated in nature. The Account model has better
programmability and the cost of bulk transactions is lower.
However, there is no dependency between transactions, and
the replay problem needs to be resolved.
G. DISTRIBUTED STORAGE SYSTEM
There are currently five large storage systems in the
blockchain: Inter Planetary File System (IPFS), Sia, Storj,
Maidsafe, and Genaro [57]. Their descriptions, advantages,
and disadvantages are shown in Appendix B. Among them,
IPFS is the most concerned system at present.
IV. BLOCKCHAIN IN OIL AND GAS INDUSTRY
According to the reports [58], [59] issued by Deloitte in
April 2017, the blockchain has great potential in the oil and
gas industry mainly in the following four aspects: trading,
management and decision making, supervision, and cyber
security. In the following subsections, the potential appli-
cations of these four aspects will be analyzed. At last, two
examples are introduced in Section IV E.
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FIGURE 6. Oil and gas industry chain [61].
A. TRADING
According to EY’s ‘‘Global oil and gas transactions review
2017’’, the total annual oil and gas transaction was
$343.5 billion [60]. The report also carried out statistics
and analysis based on the transaction volume of upstream,
midstream and downstream. The composition of the oil and
gas industry value chain has been introduced in Section I of
this paper, while Fig. 6 shows the oil and gas industry from the
specific content of the industry chain and participants [61].
It can be seen that the oil and gas industry is a multi-
link industry including exploration, development, processing,
wholesale, retail and so on. A large number of transactions
and contracts are involved in these phases, resulting in a large
amount of reconciliation work and tracking work. Accord-
ing to the survey, the application of blockchain technology
in oil and gas trading mainly includes smart contracts and
transactions.
1) SMART CONTRACT
Smart contract is a kind of contract that records terms
with computer language instead of legal language, and it is
one of the most important concepts in Ethereum [62]–[64].
Ethereum supports the development of smart contracts
through Turing complete languages (Solidity, Serpent,
Viper). As an application running in the Ethereum Virtual
Machine, the smart contract can receive transaction requests
and events from outside, and generate new transactions
and events by triggering the running code logic in advance
(Fig. 7). The results of the smart contract can be updated
for the status of the ledger on the Ethereum network, and
these modifications cannot be forged and tampered once
confirmed. Also, it has one of the most significant advantages
is that no third-party intervention is required.
Because of the huge and complex nature of the oil and
gas industry, long and complicated contracts may arise in the
trade of all parties, and the number of contracts will be consid-
erable. Smart contract can greatly reduce paperwork, simplify
FIGURE 7. Smart contract model [65].
the process, improve efficiency, and save costs. However,
smart contracts should be audited when using smart contracts
and follow smart contract security development principles
because the improper design will lead to severe loss. From
the statistical data of blockchain security incidents, smart
contract security incidents accounted for 6.67%, although
accounting for a relatively small proportion, the resulting
financial losses accounted for 43.3%. In February 2018,
several researchers in Singapore and the United Kingdom
pointed out that more than 34,000 Ethereum smart contracts
may have vulnerabilities [66].
2) TRANSACTION
In the environment of oil price fluctuation, many oil and gas
enterprises are facing tremendous pressure to reduce costs
and improve productivity, to maintain an acceptable profit
margin. In the oil and gas trading, the traditional way makes
the transaction inevitably produce errors, and the transaction
is prone to fraud and compromise. Blockchain technology
can solve the problem well [67]. It can also make the trans-
action more transparent. Both sides of the transaction can
view all the transaction records and evaluations of the other
side, thereby can improve the success rate of the transaction.
In addition, both sides of the transaction can also see the
specific situation of each stage in the transaction process,
to be more able to control the overall situation [68]–[70].
However, from a more macro point of view, there are
currently international crude oil futures such as Brent, mar-
ket participants include refineries, refined oil consumption
enterprises and so on. The purpose of trading can be either
hedging or cross-term or cross-variety arbitrage. These com-
modity futures transactions involve many processes such
as account opening certification, clearing and so on, which
makes the blockchain more useful.
Moreover, another major application of blockchain in
transactions is cross-border payments. Oil and gas are usually
sold in large quantities, especially between countries, and
the frequency of transactions is also high, which is different
from the scale of transactions between banks. Cryptographic
currency (e.g. Bitcoin and Ether) can significantly reduce the
cost of cross-border payments, in addition to instant transfers,
they can also reduce the time required for intermediaries,
as well as for verification and liquidation of funds.
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FIGURE 8. Example of using the blockchain to track LNG industry chain products.
B. MANAGEMENT AND DECISION MAKING
1) DECISION MAKING
Blockchain also has important application potential in deci-
sion making. In the exploration and development of oil and
gas, many design-related problems are involved, such as
three-dimensional data scanning of underground reservoirs,
oil and gas development programs, and design and mainte-
nance of oil and gas related devices. In current way, it usually
takes months to years from feasibility study to implemen-
tation. However, the efficiency will be greatly improved if
blockchain technology is used to not only prove the work-
load, but also calculate the relevant data. Besides, in each
stage, the blockchain can also provide a record that cannot
be tampered with, greatly helping the design process [71].
In management decision-making, many decisions need to
be made according to the information and data of the whole
system. However, it is challenging to obtain data in real time,
and a lot of information is stored in an independent system.
The structure, protocol and data format of these systems
are not necessarily the same or interoperable. Blockchain
technology can make data exchange and transmission more
efficient, thus improving the correctness of decision-making.
Additionally, many decisions in the oil and gas industry
require management level to vote, and smart contracts in
the blockchain enable automated, transparent voting applica-
tions. The voting sponsor can initiate a vote and give voting
rights to the voter. The voter can vote or entrust their votes to
others, and anyone can publicly check the result [72].
2) MANAGEMENT
The blockchain can simplify the management process and
make the management method more scientific. As we all
know, oil and gas pipeline networks occupy a vital position in
oil and gas systems, and the pipeline network is complicated
and difficult to manage, especially regarding resource alloca-
tion. If the relevant demand data and supply data are uploaded
to the blockchain and form a smart contract, the deployment
of oil and gas resources can be made more scientific. If the rel-
evant information of the pipe network can form a blockchain,
the integrity or reliability management of the pipe network
will become more successful.
C. SUPERVISION
1) TRACKING
Globally, many oil and gas products are stored, ordered,
transported and distributed through various channels such as
producers, suppliers, contractors, subcontractors, oil and gas
refiners and retailers. Once there are slips, productivity and
production level will decline, and serious cases may occur
such as loss of goods [24]. The blockchain not only tracks
products in the oil and gas supply chain, but also provides
audit trails of equipment used throughout the lifecycle, mak-
ing all aspects of the supply chain more transparent, saving
logistics costs and improving operational efficiency, this is
also the most essential function of the blockchain to solve
the oil and gas industry chain management. In recent years,
LNG has become the mainstream of natural gas trade. Due
to its low-temperature characteristics, the import and export
carriers are mainly shipping. Fig. 8 shows a tracking case of
LNG in the supply chain. Natural gas is extracted from the gas
field and then transported to the natural gas treatment plant
for dehydration or decarbonization. The purified natural gas
is transported to the liquefaction plant for LNG production
and then to the LNG export station for storage. LNG is loaded
at the export station and enters the shipping phase. After
arriving at the LNG terminal at the target location, LNG is
then gasified into the application phase.
This process involves multiple stakeholders, each of whom
maintains their own database to track the product. This
blockchain not only means that there is a shared database that
can track the product, but also means that it is an auditable
information tracking system (because it can be encrypted and
verified). For example, from the LNG shipping to the LNG
terminal stage, when the LNG arrives at the LNG terminal,
the shipping personnel will send the signed information to the
smart contract, so that everyone in the chain will know that the
LNG has arrived at the LNG terminal of the target location.
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On the other hand, when the transaction is signed, it is sent
to the recipient in an encrypted manner to let them verify that
the LNG has indeed arrived. At this time, the staff of the LNG
terminal issues the same smart contract for confirmation.
Similarly, the same method also can be used for tracking
related devices.
The tracking function of blockchains can be applied not
only to the product or asset tracking, but also to intellectual
property tracking. Due to advances in technology, the oil and
gas industry will involve much content related to intellectual
property. However, the legal copyright registration fee is high,
and even if the copyright registration is applied, the approval
time is long. Blockchain technology can store and track
related content, realize the traceability of ownership, and thus
achieve the role of intellectual property protection.
2) COMPLIANCE
Due to the high degree of transparency of blockchain
technology, it can improve compliance in the oil and gas
trade [73], such as increasing the consistency of the Dodd-
Frank Act [74], the Extractive Industries Transparency Ini-
tiative [75], and the European Union directives [76]. The
data generated by the blockchain is shared within the
‘‘Trust::Data’’ framework proposed by the Massachusetts
Institute of Technology, which significantly reduces compli-
ance costs and increases speed [77].
Besides, some bidding or management issues during oil
and gas exploration and development can also be solved by
blockchain. For example, the problem of invalid bidding,
the liability of contracting negligence in project bidding,
and the civil liability for refusing to sign the contract after
winning the bid.
3) DATA RECORD
Oil and gas companies need to obtain land use rights before
conducting exploration, development and other activities.
However, understanding the source of the land can be diffi-
cult, and there may be multiple records of ownership conflicts
in a separate database. In this environment, land transactions
are highly vulnerable to fraud. Blockchain technology can
create an invariable audit trail of land mobility, value and
ownership. This will reduce the loss or mismatch of owner-
ship, the occurrence of ownership disputes, and provide tax
authorities with the transparency of land transactions, real-
time record of the accurate transfer of value [78].
D. CYBER SECURITY
According to statistics, in 2016, nearly three-quarters of oil
and gas companies in the United States experienced at least
one cyberattack. For hackers, oil and gas companies have
many vulnerable breakthroughs (oil and gas enterprise struc-
ture is shown in Fig. 9), such as complex operating system and
production process, little intersection of information tech-
nology (IT) and operation technology (OT), delay of real-
time system caused by firewall, inconsistency of network
standards among departments, irregular updating of system
security patches (especially vendor’s security system), and
FIGURE 9. Oil and gas enterprise structure [79].
historical legacy problems [79]. For example: intelligent sen-
sors can provide important information such as the real-time
status of offshore oil field operations, but these sensors are
currently the most insecure part of the enterprise network
because it is possible for industry competitors to obtain such
information through espionage activities. If blockchain tech-
nology is used to store important data in a distributed manner,
the risk of network attacks can be effectively reduced. In order
to increase the data security of enterprises, financial technol-
ogy developers are developing projects in the ‘‘Trust:: Data’’
framework, including OPAL, Digital Personas and Identity,
Tradecoin, MIT Enigma, OpenPDS [80].
E. EXAMPLES: VAKT AND KOMGO SA
At present, the application of blockchain technology in the
oil and gas industry is in its infancy. Two well-known related
blockchain projects are: Vakt and komgo SA [81].
Vakt is a blockchain-based commodity trading post-
processing company. On November 29, 2018, it announced
the world’s first enterprise-level blockchain platform for the
crude oil industry. Its first users include BP, Equinor, Shell,
Gunvor, and Mercuria, and will launch larger products in
January 2019. Their goal is to increase speed and security,
which benefits everyone in the supply chain from market
participants to customers. VAKT uses J.P.Morgan’s Quorum
blockchain technology. Quorum is a blockchain platform
based on Ethereum, but it has higher privacy and a variety
of voting-based consensus mechanisms [82].
Another important project, komgo SA, is a blockchain
platform for commodity trading that is supported by com-
modity supply contracts. It is also jointly developed by many
companies, and the first operation of komgo SA will be crude
oil transportation in the North Sea. It is expected that in early
2019, the platform’s transactions will expand to new areas:
metals and agricultural products. Since then, the scope of the
platform will continue to expand [83].
V. DISCUSSIONS
This section will discuss issues such as the application status,
opportunities, challenges, risks and development trends of
blockchain technology in the oil and gas industry.
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TABLE 7. Major oil and gas blockchain projects [87].
FIGURE 10. Statistics on 12 major oil and gas blockchain projects. (a) By region. (b) By status.
A. APPLICATION STATUS
In the past two years, blockchain technology has begun
to emerge in the oil and gas industry. Many energy
giants have begun to invest in the development of this
technology. Among them, BP and Shell are pioneers
in blockchain application technology in the oil and gas
industry.
At the end of 2017, Sinochem Group successfully com-
pleted China’s first blockchain crude oil import trading pilot
project from the Middle East to China [84]. There are two
major applications in the project – digital bill of lading
and smart contracts, which can significantly improve the
efficiency of crude oil trading execution and optimize the
transaction financing cost by 20% to 30%. In addition,
the blockchain platform jointly developed by Abu Dhabi
National Oil Company (ADNOC) and IBM will be the first
application of blockchain technology in global oil and gas
production accounting [85], [86]. Unlike other projects, it will
apply to the entire oil and gas life cycle, not just a critical
part of the commodity supply chain. ADNOC expects to
automate the transaction process through the platform, and
by deploying advanced technology resources, it will reduce
its drilling time by 30% in 2019 and achieve savings of
up to $1 billion.
Table 7 lists 12 major oil and gas industry blockchain
projects worldwide [87], and Fig. 10 summarizes the status
of these projects from the region and status. It can be seen
that as of mid-2018, most of the blockchain projects in the
oil and gas industry are in operation and commissioning, and
some are in the testing stage. Europe has the largest number of
projects, and Asia and Europe have the fastest development
in the application of blockchain in the oil and gas industry.
But overall, there are few blockchain projects in the oil and
gas industry relative to other industries.
B. UNDERSTANDING LEVEL
From the perspective of understanding blockchain in the
oil and gas industry, this paper summarizes the following
information from the statistical records of 1053 respondents
in ‘‘Deloitte’s 2018 global blockchain survey’’ [8]:
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TABLE 8. Common misunderstandings about blockchain [88].
(1) 72% of respondents in the oil and gas industry believe
that blockchain technology will have a big impact on the
industry;
(2) 61% of respondents in the oil and gas industry believe
that the blockchain is only a currency database and can only
be used in the financial services sector;
(3) Regarding the level of understanding, 87% of respon-
dents in the oil and gas industry believe that their understand-
ing of the blockchain is ‘‘Excellent’’ rather than ‘‘Expert’’
(only two levels in this survey);
(4) In terms of investment in blockchain technology, 72%
of respondents in the oil and gas industry invested between
$1 million and $10 million, while only 9% invested more
than $10 million. In contrast, 38% of respondents in the
automation field invested more than $10 million in their
organization;
(5) Only 15% of the organizations in the oil and gas indus-
try have applied the blockchain to production, while 84% are
only in the consciousness or experimental phase.
For another report [88], the World Energy Council inter-
viewed 39 people in the energy field in 2018 and released
a report called ‘‘Is blockchain in energy driving an evo-
lution or a revolution?’’. They have a maturity model
based on the interviewees’ responses. It can be concluded
from the two survey reports that the understanding of the
blockchain by the oil and gas industry is not comprehensive
enough (Table 8 summarizes some common misconceptions
about blockchain), and the application of the blockchain is
still in the experimental stage. In addition, the oil and gas
industry’s investment in the blockchain is not strong enough.
C. OPPORTUNITY AND CHALLENGE
Due to the decentralization and transparency of the
blockchain, it can bring many opportunities to the oil and
gas industry [91]. However, a new technology will inevitably
encounter many challenges when it is first applied, as shown
in Table 9.
D. RISK
Although the blockchain technology has many advantages,
the current operating system is still not perfect, and there are
many risks. Risks can be divided into operational risks, cyber
risks, and legal risks [92]–[95].
Operational risk means that if the blockchain is applied to
the oil and gas industry, technical or social problems may
produce bad results. It may be reflected in:
•Loss of data and identity.
•The transaction costs of the public blockchain are high.
•Lack of recipients and users.
•Lack of long-term experience leads to imperfect
management.
•Initial applications may have technical problems.
•Lack of a standardized mode of operation, function and
security deficiencies.
Cyber risk refers to bad behavior such as fraud due to
insufficient security or design flaws, it is reflected in:
•There may be fraud in the interface between the real
world and the blockchain world.
•The exchange may be attacked by hackers, and the user’s
password may be hacked and funds transferred.
•The hard fork of the block will cause the trust of the
entire network system to be questioned.
Legal risk refers to some illegal acts that may occur in
the operation of block chains, it is reflected in:
•Tax evasion may be triggered.
•Illegal use of information.
•Blockchains are used for illegal transactions.
E. DEVELOPMENT TRENDS
The blockchain has been in development for a decade, from
the earliest application to bitcoin to the present application in
various industries. However, blockchain technology is con-
tinually improving and is striving to find a better application
experience. This paper summarizes the future development
trends of blockchain technology in the oil and gas industry
from five aspects.
1) HYBRID BLOCKCHAIN ARCHITECTURE [100]
Consortium blockchain is currently the main implementation
of the blockchain project, but it does not have the scalabil-
ity and anonymity of the public blockchain. However, with
the development of blockchain technology, the oil and gas
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TABLE 9. Opportunities and challenges of blockchain in the oil and gas industry [16], [96]–[99].
industry will not be satisfied in the future by applying
blockchain only between enterprises, and a hybrid architec-
ture of ‘‘Public blockchain for the masses and consortium
blockchain for enterprises’’ can be formed.
2) COOPERATE WITH OTHER TECHNOLOGIES [101]–[105]
In recent years, not only blockchain technology is rapidly
developing, but other technologies such as artificial intel-
ligence, big data, and cloud computing are also advancing
rapidly. However, these techniques can aid in the devel-
opment of blockchains. For example, artificial intelligence
based on blockchain uses smart contracts in terms of user
equipment registration, authorization, authentication, and
value exchange to improve security. The combination of
blockchain and cloud computing will effectively reduce the
cost of blockchain deployment. In addition, the blockchain
will promote the development of other technologies. For
example, various artificial intelligence modules can imple-
ment links through blockchains and can learn on the chain to
promote the evolution of artificial intelligence.
In a practical case, the Blockchain as a Service (BaaS)
system developed by the combination of blockchain and
cloud computing aims to provide users with better blockchain
services. Therefore, BaaS service providers pay more atten-
tion to the vertical industry connection, to provide reasonable
smart contract templates, good account system management,
good resource management tools, and customized data anal-
ysis and reporting systems.
3) CROSS-CHAIN AND HIGH-PERFORMANCE
BLOCKCHAIN [106]
At present, each blockchain network is a relatively inde-
pendent network, and data information cannot be inter-
connected. Cross-chain technology makes blockchain suit-
able for industries with complex scenarios. Current main-
stream cross-chain technologies include Notary schemes,
Sidechains/relays, Hash-locking, and Distributed private key
control. Due to the complexity of the oil and gas system,
multiple blockchains can be established according to different
scenarios. Cross-chain technology can realize digital asset
transfer between multiple blockchains, thereby improving
efficiency.
In addition, in order to improve the throughput of the
blockchain system, many scholars and experts are develop-
ing high-performance blockchain solutions. There are cur-
rently three ideas for improving performance. The first is
to change the blockchain topology to a transaction-based
Directed Acyclic Graph (DAG). The second idea is to change
the consensus strategy to increase throughput by reducing the
number of nodes participating in the consensus. The third
way is to improve the overall throughput of the system by
increasing the horizontal scalability of the system.
4) HYBRID CONSENSUS MECHANISM [107], [108]
Due to the critical position of the consensus mechanism in
the blockchain, it will continue to develop. There are many
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TABLE 10. The emergence time, basic algorithm, and Byzantine fault tolerance performance of 32 mainstream consensus algorithms [33].
consensus mechanisms, each with its own advantages and dis-
advantages. The application of a single consensus mechanism
has other flaws. In order to improve efficiency and security,
the consensus mechanism will be developed towards a hybrid
consensus mechanism and will be dynamically configured
according to different situations in different application sce-
narios or running processes.
5) MORE INTERDISCIPLINARY PROFESSIONALS [109]
The global demand for blockchain talents has grown since
2015 and experienced explosive growth in 2016-2017, but
for now, its share of global talent market demand is still
meager. Blockchain technology is a multi-disciplinary and
cross-disciplinary technology. Compared with the talents of
R&D technology, the blockchain underlying system archi-
tecture design talents need to master several interdisciplinary
professional skills and understand the underlying design prin-
ciples of blockchains, which means that the oil and gas market
needs professionals who have both the experience of system
architecture design and know the specific business of appli-
cation scenarios. Therefore, more professionals in the future
will be more inclined to implement the blockchain, and more
inclined to interdisciplinary.
VI. CONCLUSIONS
This paper does a systematic review to discuss the applica-
tion prospects of blockchain technology in the oil and gas
industry, and the main purpose of this paper is to expand the
influence of blockchain technology in the oil and gas industry.
In summary, blockchain technology has excellent potential in
the oil and gas industry, but since it has just started in the last
two years, there are many opportunities, challenges, and risks.
Specifically, this paper first introduces the core theory
of blockchain technology in Section III, including the con-
sensus algorithm of the blockchain, data record model and
distributed storage system. Secondly, this paper demonstrates
the possible application modes and scenarios of blockchain
in the oil and gas industry from four aspects in Section IV:
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TABLE 11. Introduction, advantages and disadvantages of five distributed storage systems [57].
trading, management and decision making, supervision and
cyber security. Finally, this paper discusses the application
status, opportunities, challenges and risks of blockchain tech-
nology in the oil and gas industry, and also analyzes the future
development trends in Section V. The following conclusions
were drawn:
•Europe and Asia are the most powerful in promoting the
blockchain in the oil and gas industry, and BP and Shell
are pioneers in this field.
•At present, the application of blockchain in the oil and
gas industry is still in the experimental stage, and many
people in the oil and gas industry do not understand
enough.
•Blockchain technology can bring many opportunities to
the oil and gas industry, such as reducing transaction
costs and increasing transparency. However, it also faces
many challenges and needs to address many technical
and regulatory issues.
•Blockchains may have operational, legal, and cyber risks
in the oil and gas industry.
•In order to meet market and management needs, the
blockchain will move toward the hybrid blockchain
architecture, cross-chain, and hybrid consensus mech-
anism in the oil and gas industry.
APPENDIX A
See Table 10.
APPENDIX B
See Table 11.
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VOLUME 7, 2019 41443

H. Lu et al.: Blockchain Technology in the Oil and Gas Industry: A Review of Applications, Opportunities, Challenges, and Risks
HONGFANG LU received the B.E. degree and
M.S. degrees in oil and gas storage and trans-
portation engineering from Southwest Petroleum
University, Chengdu, China, in 2013 and 2016,
respectively, where he was a Graduate Student
with the State Key Laboratory of Oil and Gas
Reservoir Geology and Exploitation, from 2013 to
2016. He is currently pursuing the Ph.D. degree in
civil engineering with Louisiana Tech University,
Ruston, LA, USA, where he has been a Graduate
Assistant with the Trenchless Technology Center, since 2017.
His research interests include trenchless technology, energy technology,
pipeline technology, and computer science and related interdisciplinary pro-
fessional skills.
Mr. Lu is a Student Member of the American Society of Civil Engineers
(ASCE), Society of Petroleum Engineers (SPE). He was a recipient of the
NASSCO Jeffrey D. Ralston Memorial Scholarship, in 2018, and the Heather
Berry Scholarship, in 2018.
KUN HUANG received the B.E. degree in oil and
gas storage and transportation engineering from
Southwest Petroleum University, Chengdu, China,
in 1985, and the M.E. degree in computer applica-
tion from the University of Electronic Science and
Technology of China, in 1998.
From 1985 to 1999, he was a Lecturer with
the School of Mechanical Engineering, Southwest
Petroleum University, where he was an Associate
Professor with the School of Petroleum Engineer-
ing, from 2001 to 2008. Since 2008, he has been a Professor with the School
of Petroleum Engineering, Southwest Petroleum University. His research
interests include oil and gas pipeline engineering, and oil tank design and
management.
Mr. Huang is currently a member of the Expert Committee of China
Natural Gas Industry Association and the Natural Gas Industry Edito-
rial Committee. He is an Expert in Sichuan Petroleum and Natural Gas
Production Safety.
MOHAMMADAMIN AZIMI received the B.Sc.
degree in civil engineering from Razi Univer-
sity Kermanshah, Iran, in 2007, and the M.Sc.
degree in civil engineering (structure) from Kur-
distan University Sanandaj, Iran, in 2010, and
the Ph.D. degree in civil engineering (structure-
earthquake) from the University Teknologi of
Malaysia (UTM), in 2014.
He is a former Faculty Member of the Depart-
ment of Structure and Materials, Faculty of Civil
Engineering, University of Technology Malaysia (UTM). He is currently a
Research Scientist/Adjunct Professor of civil engineering with Trenchless
Technology Center (TTC), College of Engineering and Science, Louisiana
Tech University. His research interests include the smart and innova-
tive structures, green and innovative concrete, and sustainable and green
technology.
Dr. Azimi has received several National and International Awards for
his inventions in the field of innovative engineering, such as Intelligent
Earthquake Resistant Beam-Column Connectors (SEER-iSPRING) and
Intelligent Flood Management Software (i-FLOOD). His latest invention
Multi-Functional Green Interlocking Mortarless Concrete Block (LOCK-
BLOCK) manages to win several international award such as the Best Amer-
ican Inventor Award, Gold, and Special Award from SVIIF 2018-Silicon
Valley.
LIJUN GUO received the B.S. degree in measure-
ment and control technology and instruments from
the China University of Mining and Technology,
Xuzhou, China, in 2004, and the Ph.D. degree in
microelectronics and solid-state electronics engi-
neering from the University of Chinese Academy
of Sciences, Beijing, China, in 2017.
She is currently a Researcher with the China
Center for Information Industry Development,
where she was mainly involved in research of soft-
ware industry planning and implementation evaluation, focusing on the new
generation of information technology, such as the Internet plus, artificial
intelligence (AI), blockchain, and the Internet of Things (IoT).
41444 VOLUME 7, 2019