Software drives plant optimisation improvements

Paul Boughton

New software solutions are delivering better machine and overall plant optimisation, helping process operators to improve both process and plant performance. Sean Ottewell reports.
Aspen Technology has just released its aspenONE V8 software which includes a number of new tools: a new version of Aspen HYSYS; solids modelling functionality (acquired from SolidSim in 2012) integrated within Aspen Plus; the new Aspen PIMS Platinum; a new version of Aspen Collaborative Demand Manager; and breakthrough innovations in advanced process control, energy and economic analysis.
The company says that using its new software will enable new and occasional users become proficient faster, while experienced users can do more: “This is critical for process industry companies facing workforce development and skills shortages. Usability and visualisation enhancements in aspenONE V8 also enable users to collaborate more easily, shortening project times and increasing productivity.”
In terms of the new Aspen HYSYS, this comes with increased simulation usability and a redesigned interface to streamline both workflow and interactive analysis. It will make it easier and faster to generate optimised process simulations – particularly for the hydrocarbon industry.
The integration of SolidSim technology eliminates silos between previously disparate solids and liquids modelling processes – making it possible to optimise all chemical processes together for the first time.
The new ‘Activate’ feature in Aspen Plus and Aspen HYSYS allows process engineers to find energy and capital cost savings faster. Through activated energy, process engineers can quickly identify ways to change designs to reduce energy, saving design time and future operating costs.  Employing activated economics, process engineers can apply science rather than intuition to ensuring the best use of capital.
 Meanwhile the new Aspen Collaborative Demand Manager provides the information granularity customers need to manage different forecasting requirements.  Process manufacturers can improve demand forecast accuracy to increase customer service levels, reduce excess inventory, and provide better input to purchasing decisions.
The company is already getting positive feedback from early users of the new software.
“The New HYSYS looks great and is a step ahead in terms of ease of use. The innovations that AspenTech has introduced in aspenONE V8 will help Petrofac optimise designs for customers, reduce project risks and improve the quality and speed of our process engineering work,” said Christo Viljoen, director, Engineering Solutions Group, Petrofac.
“Aspen PIMS Platinum changes the way that planners can make decisions, making it faster and easier. The post solution analysis capability has been significantly enhanced with this new set of features including 2D or 3D graphs,” explained Paul Gallagher, refinery planning manager, Samsung Engineering.
“We have been using Aspen Plus and SolidSim to model the fluids and solids sections of our processes.  The integration of SolidSim into Aspen Plus enables us to design and optimise the entire process with one simulator and consistent physical properties,” added Ingrid Lunt-Rieg, head of process modelling and computational fluid dynamics, Evonik.
Explaining his company’s view on the new release, Manolis Kotzabasakis, executive vice president, products, AspenTech, said, “Our product teams are passionate about developing breakthroughs in process software, finding new ways for customers to optimise their operations.  aspenONE V8 extends the boundaries of process optimisation; our customers are very excited by the value it is already delivering. As we continue to make aspenONE software easier to use, more process industry professionals will be able to work together to make faster and more profitable decisions for their companies.” [Page Break]
Optimising utilities
When it comes to plant optimisation, one of the key offerings from Invensys Operations Management is ROMeo Utilities Optimisation. This improves the way process plants supply energy from utilities including steam, water, power and fuel.
With the rising cost of energy and stringent environmental regulations, companies are increasingly focused on improving energy efficiency. The cost of power and utilities is often the largest controllable operating expense after the purchase of raw materials at most large operating sites.  
ROMeo Utilities Optimisation software automatically, and in real-time, optimises its energy supply within the context of changing economic and plant needs and environmental constraints. It is especially attractive for plants that have varying energy prices or the changing possibilities to buy, produce or sell power.
The solution can result in significant reductions in energy cost, with a typical payback in 6-12 months or less.
Key benefits include: a 3-5 per cent reduction in energy consumption; ability to reduce carbon dioxide, SOx and NOx emissions; automatically takes advantage of off-peak power pricing; optimises fuel type, boiler and turbine load distributions; and better fuel gas management with fewer alarms.
The solution is capable of rigorously modelling all components of a typical industrial utility system including turbines, boilers and power distribution systems. Its patented graphical scheduling system enables automation of data gathering, model execution and reporting. Other capabilities include integrated data reconciliation and identification of faulty instruments. In addition, when used with Wonderware Intelligence, it is possible to develop key performance indicators for energy costs and operational impact.
Recently Invensys also added to its plant optimisation offerings with a new solution that complements its existing portfolio of SimSci-Esscor hydrocarbon processing industry (HPI) offerings.
To help refiners meet the increasing demands of today’s operating environment, the company has issued two new offerings: a yield accounting solution and an off-sites solution integrated with planning and scheduling systems.
The company further announced that it has acquired Spiral Software, a privately held company headquartered in Cambridge, UK. Spiral Software provides the only integrated refining-industry solution designed from the ground up, bringing together feedstock data management, planning and scheduling.
This means that Invensys Operations Management’s SimSci-Esscor solutions will now fully support and optimise the entire refining value chain, from crude trading to supply-chain distribution, including lifecycle modelling from design to start up to performance optimisation – potentially saving customers millions of Dollars every year (Fig. 1). [Page Break]
 Optimising confectionary processes
Operating from sites in the UK and USA, Baker Perkins is a world leader in the supply of high-output machines and complete process lines to the worldwide confectionery industry. The company’s machines and services utilise the latest technology, to maximise efficiency and minimise cost of ownership.
The company’s new generation ServoForm depositor is used for sugar confectionery such as hard and soft candies, lollipops, toffees, fondants, fudges and jellies. The servo technology used offers much greater flexibility and control leading to lower labour costs, reduced energy bills and faster payback.
An Allen-Bradley CompactLogix programmable automation controller (PAC) from Rockwell Automation controls all aspects of machine operation while an Allen-Bradley PanelView 1250+ touch screen HMI, mounted in the main control panel, helps operators to set up and monitor both the cooking and depositing processes from a single location.  
Initial process settings are stored as a recipe and are downloaded to the machines, setting up the line at the touch of a button. The new ServoForm uses Allen-Bradley PowerFlex variable-speed drives combined with Allen-Bradley Kinetix servo drives to adjust and synchronise the various movements of the head, pistons and mould circuit for maximum precision and efficient continuous operation. As well as recipe control, the PAC and HMI provide full process visualisation, including real-time historical trending plus alarm management and history.
As well as more effective process-variable control, the machine’s washout cycle has also been automated. In the older machines, trays were manually positioned between the depositor heads and moulds prior to washout with hot water, now they come in automatically, controlled by the PAC, removing the last remaining major labour element from the machine.
According to Keith Graham, marketing manager at Baker Perkins: “As well as the outstanding machine and line performance we can offer, we are also committed to offering the best possible service. We never want to be in a position where we cannot service our machines, so with its international network, Rockwell Automation is our preferred automation provider.”[Page Break]
Model-based engineering reduces costs, increases throughput
When carrying plant optimisation projects, PSE uses its proprietary model-based engineering approaches to reduce costs, increase throughput or quality and support capital decisions.
Model-based engineering uses detailed predictive models of the process (or key elements of it) to identify significant improvements. These often do not involve capital expenditure: they may identify actions as simple as changing process operating temperature and pressure, or implementing a new seeding policy for a crystallisation process.
In many cases the same model can be used for many different investigations, or applied on a regular basis as market conditions change, generating multiple return on investment in modelling activities.
In terms of benefits, modelling can often identify ways to achieve the following without significant capital expenditure: reduce costs and improve quality - one customer’s polymer process batch time was reduced by 35 per cent; increase throughput or quality; reduce energy costs; reduce raw material costs; improve return on capital employed; extend catalyst life, reducing cost; and enhance compliance with environmental or safety requirements.
PSE recently carried out a model-based engineering project on one of Samsung Petrochemicals’ purified terephthalic acid (PTA) plants in Korea. The company has long experience with this product and used a set of high-fidelity process models and advanced methodologies for the detailed modelling and optimisation of the process itself.
The two companies are expecting a reduction in paraxylene consumption that could save up to €1 million/y, a reduction of up to 15% in acetic acid consumption – saving a similar amount, and better optimisation of operating conditions – allowing more raw material flexibility.
Model-based engineering can also be used in the re-design of equipment for changing production, for example to establish optimal impeller design and nozzle placement.