Deaglan Gahan explains the basics of the internet of things (IoT) and puts the technology in context for chemical engineers
THE internet of things (IoT) is a rather vague term that may refer to different features of a digital product or system. IoT is finding its way into the process industries, where its application is often called the industrial internet of things (IIoT).
The promises made around IoT are often grandiose and dressed in jargon. IoT has appeared at a similar time to other digital technologies including artificial intelligence (AI), digital twins and cloud computing, and the scope and definitions of these broad categories can include and overlap with IoT. Digitalisation is increasingly expected to be adopted wherever possible. Chemical engineers are often project managers, engineering managers or in other roles that oversee the adoption of new technologies, so they should be aware of the limitations and implications of emerging technologies including IoT. IoT is a tool and not a solution in and of itself, so any advocacy for digitalisation is an opportunity for the use of IoT. In this article, the eighth in the series on digitalisation from DigiTAG, we will present definitions, typical use cases, and practical benefits and trade-offs of adopting IoT technologies in the process industries.
Precisely what constitutes IoT technology versus conventional digital solutions is debatable, with publications dedicated to this topic alone.1 Within the context of the process industries, most “things” (IoT devices) are classified as such based on either their physical form or the way they communicate. The physical categorisation of IoT devices is the more intuitive classification and relates to the scale of the things. Small, internet connectable devices have evolved into commodity items (eg an ESP8226 or Arduino microcontroller, and platforms like Raspberry Pi) and are extremely affordable for experimentation and production deployments. This makes projects requiring many small, networked devices feasible. The increasingly popular “smart home” concept, which sees the likes of light bulbs, power sockets, security cameras, and climate control being commanded through a common platform such as a mobile phone, is a good domestic example of IoT.
The communications definition of IoT is more technical. IoT devices typically transmit and/or receive data using the same type of connection that a personal desktop computer uses – Transmission Control Protocol/Internet Protocol (TCP/IP) – which can be wired or wireless. There are two common TCP/IP languages (or protocols) used to implement IoT - HTTP (Hypertext Transfer Protocol – the same protocol used to navigate the internet) and MQTT (Messaged Queueing Telemetry Transport). There is no rule that an IoT device needs to use these protocols. However, TCP/IP, HTTP and MQTT are robust and well established in other industries, and it makes sense to adopt them to develop IIoT projects as it is then easier to find external expertise. Sticking to common protocols also enables simpler connectivity with other systems. This is juxtaposed with the classic 4-20 mA HART connectivity which is relatively esoteric to industrial applications. Software services hosted by third parties (better known as “the cloud”) are easier to integrate with, alleviating the need for intermediate equipment and programming.
Despite their name, IoT devices do not need to be connected to the internet. They can be standalone or added to a private network like a corporate intranet. Many of the same benefits can be realised without the cybersecurity risks of connecting devices to the internet. However, private hosting increases the number of services that need to be available and maintained within the corporate network. These added costs may outweigh the advantages of an IoT-based solution.
IoT has appeared at a similar time to other digital technologies including artificial intelligence (AI), digital twins and cloud computing, and the scope and definitions of these broad categories can include and overlap with IoT
There are two key advantages to using IoT technologies; enabling low-cost data acquisition and transmission, and greatly simplifying intra- and inter-organisational connectivity. These two strengths can often be realised in tandem.
The low cost of IoT sensors is attractive to smaller operators who may not have full-fledged SCADA (Supervisory Control and Data Acquisition) systems already deployed, or for whom the cost of engineering resources is a deterrent to installing more field instrumentation. IoT packages usually integrate with non-industrial infrastructure, similar to the consumer-grade wireless network you may have in your home. Industrial control infrastructure is increasingly being supplied with the prerequisites to communicate directly with IoT devices via TCP/IP and HTTP/MQTT, enabling external access to integrate third party data or services without additional hardware or software. Packaged equipment suppliers are also starting to provide preconfigured IoT options. Asset owners can therefore often use low-cost IoT technology instead of conventional control systems which have a significant cost of ownership.
Standalone IoT instrumentation offers a risk reduction as it can be implemented independently of the industrial control system. There are reliability implications for IoT field devices. However, if these are acceptable (eg temporary monitoring) then a self-contained IoT package can significantly reduce the cost of automation engineering resources associated with SCADA or distributed control system changes (for example, by simplifying and reducing new input/output (I/O) requirements, and database and historian configuration). Inherently voiding all work on the plant control systems also eliminates the risk of altering the plant control system for a temporary purpose.
Smarter field devices have the potential to create better informed field operators. Field instrumentation traditionally sends a signal to a controller for further processing, display, or analysis. Complicated analysis may take place only in a remote, segregated system. An IoT device installed in the field may be capable of all these in a single package and so calculated values (“soft signals”) and important information not directly read from the field, like batch numbers, may be readily available.
A good example of where IoT could be of significant intra- and inter-organisational benefit is the energy industry. Traditionally, the industry relies on relatively slow, manual communications to work across operating jurisdictions to plan production allocations and to then meet that allocation. The emergence of renewable energy and particularly green hydrogen developments will see a demand for faster energy market responses where swift inter-organisation communication will be essential for efficient operation of the network. These practices already exist by other names and as the jargon develops then “IIoT” may become a part of parlance.
Inter-organisational connectivity in the energy and other industries may present itself in different ways, eg:
A widely used inter-organisational IoT system sends plant data directly to a third-party service for monitoring (typically done nowadays via the cloud). This practice is sometimes known as telemetry. This application is increasingly used by suppliers who monitor clients’ tank levels for replenishment, or by service providers who monitor asset performance independent of the operators’ infrastructure. The benefits are similar to intra-organisation applications, but with the added advantage of making package integration more seamless by eliminating instrumentation and control interfaces at the supplier-client boundary. IoT can also simplify commercial arrangements by removing the providers’ reliance on their clients’ facilities for connectivity, at the cost of relying on the internet connection to be suitably robust and secure. The owners’ desire to access the data themselves and their tolerance to subscribing to the providers’ ways of working may also be a consideration. Integrating the data sent to the supplier back into the client’s control or visualisation systems is doable, but may be contrary to the benefits of selecting an IoT design to start with.
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