According to the Microsoft whitepaper ‘Bringing autonomy to the industrial control system’, “Industrial control systems form the backbone of businesses across sectors, but existing systems have limitations. Traditional controllers like MPCs [model protective control], PIDs [proportional-integral-derivative] and APCs [advanced process control] operate on a set of deterministic instructions in predictable environments.
"While these control systems effectively perform one task at a time, human operators must manually retune machine settings for different scenarios, conditions or goals. For example, an operator would have to adjust a bulldozer controller, depending on whether it’s operating in wet, rocky or sandy soil. Additionally, these existing technologies are only capable of focusing on one optimisation goal at a time – like maximising throughput or minimising energy usage” (www.is.gd/zuguta)."
There are user constraints to these systems as well. It’s often difficult for operators and engineers to manage variables across disparate systems. Different levels of complexity within each system can mean there are gaps between what novice and expert operators accomplish with them, making it difficult to ensure consistent management of systems across facilities. “This is a challenge for many manufacturers,” adds Microsoft. “Currently, 40% of manufacturers lack skills to build or run Industry 4.0 systems (www.is.gd/umagov). Achieving digital transformation means being able to take advantage of innovative technology and empowering employees to work more efficiently.”
INTELLIGENCE-DRIVEN GAINS
These are the kinds of challenges that Rolls-Royce has actively embraced. It employs 2,500 at the jet engine manufacturing plant in Glasgow, which produces aerofoils and shafts for new engine production. It operates to a ‘zero defect’ process, hence quality is vital. Moreover, it has ambitious sustainability targets, including an energy optimisation target of 5% reduction year on year.
The push to achieve such goals was demonstrated on a recent project where costs relating to process control equipment, including valves, were proving excessive. Fast forward to the intelligent electronic pumps solution from Grundfos chosen for this venture, which is integrated into the Rolls-Royce’s SCADA system, enabling it to do predictive analysis and data consultancy remotely. With three Grundfos CRE 32-7 pumps installed and commissioned, the total pump energy saving has been measured at 1,380 MWh per year. Plus, after the implementation of pressure wave analysis measuring the level of water hammer, this dropped from peaks of 40 Bar to just 5 Bar. Rolls-Royce now wants to work towards site standardisation on similar intelligence-driven solutions across multiple locations.
This option of monitoring performance data, including remotely, gave the company a new set of tools for its maintenance work, as it now operates to a much more efficient level when carrying out predictive maintenance and condition monitoring of its pumps. This is allowing the company to avoid downtime, while reducing energy consumption. “Today, we are all aware that there is increasing pressure on margins at every point in the value chain,” states Grundfos Pumps product manager Glenn Miller. “At Rolls-Royce, for example, through advanced monitoring and predictive maintenance, we’ve been able to deliver substantial energy savings, optimisation advantages and controls chain reduction. Also, you don’t have a situation where, if a PLC system goes down, things can come to a grinding halt, since everything works autonomously.
“By thinking beyond the pump and taking the entire pumping system into account, it is possible to optimise the way pumps, drives, controls and protection, measurement and communication units work together as part of one system. For instance, Grundfos can incorporate specific demands with our application expertise, and then take these requirements and translate them into powerful pump intelligence – for any application.”
CLOSE ENGAGEMENT
There are many benefits to adopting such an approach, he adds, from the savings and productivity gains achieved through improved efficiencies to ensuring that the pumps, controls, sensors, variable frequency drives, connectivity and software are all fully-aligned. If there is a ‘downside’, it’s that initial outlay is high and the plant operator has to be sure that the technology acquired is precisely what is required. “It’s a journey that’s all about client-supplier engagement,” says Miller, “one that identifies the pumps and drives that will not only improve plant processes, but also deliver a potent ROI [return on investment] of typically around 18-24 months.”
As the need to optimise and control speed continues to gain in importance within areas such as building services, industry and wastewater applications, the focus on synchronised, intelligent systems has become a key factor in making that happen. Not to take that path, suggests Miller, is tantamount to buying a television from a bygone era and sticking with it, despite all of the advances achieved since (broadband internet, connected devices and video streaming services).
“Technology moves on and plant operators have to embrace this,” he says. “They function in an environment where everyone is looking to produce more for the same or less cost. If you simply stick with the solutions you’ve always had, that productivity just won’t happen, for all the reasons it is happening at Rolls-Royce, and those of your competitors with a different mindset will leave you behind.”
WASTEWATER CHALLENGES
Switching attention to optimised water treatment performance, getting that recipe right at a pulp and paper mill might seem self-evident – the right dose of chemicals to the right place at the right time – but the varying conditions can make it difficult in practice. Real-time monitoring, measuring and control play a vital role when it comes to staying one step ahead. As far as wastewater treatment is concerned, governments globally are tightening environmental regulation, and many pulp and paper mills have stricter discharge limits over water pollutants in their permits. To ensure the outlet effluent is within allowable discharge limits 24/7, the mills require continuous treatment process stability – not that easy to achieve.
As Anders Ånäs, manager for water quality and quantity management applications at Kemira, points out: “The loads of suspended solids, turbidity and hard COD [Chemical Oxygen Demand – the total measurement of all chemicals, organics and inorganics, in water/waste water], which are particularly challenging for the mills, vary in the wastewater from hour to hour. The reality is that, in many cases, the treatment chemicals are fed into the process at a steady dosage flow. This leaves a lot of points in time where the chemicals are either underdosed or unnecessarily overdosed.”
Adding to the challenge are the time-consuming quality control processes. Typically, basic monitoring and control requires manual work in collecting samples and analysing them in a lab. This causes delays in the process. “It may take several hours or even days before the plant personnel can react to a changed wastewater composition and take corrective actions to adjust the chemical dosage and optimise the treatment process performance. As a result, the mills face unstable and at times poor effluent quality and, on the other hand, chemical wastage and unnecessary costs.”
Kemira has developed digital services that help optimise the performance of different water treatment processes at pulp and paper mills. The KemConnect Water Treatment solutions enable real-time measuring, monitoring, and control of different water treatment applications: wastewater, internal process water and raw water treatment, sludge dewatering, and odour and corrosion control. “The real-time view helps in overcoming many challenges,” Ånäs points out. “In the customisable KemConnect dashboard, you can see at a glance the current levels of COD, suspended solids, turbidity or hydrogen sulfide (H2S) in your process and how the current treatment is performing. Based on the data, the mill personnel can make fact-based and timely decisions, leading to round-the-clock stable quality and optimised performance.”