Virtual challenges

Global oil and gas demand is predicted to increase by 50% to 2030, driven by escalating consumption in India and China. To meet this challenge oil & gas companies are working to develop advanced technology that will provide more efficient production from old wells and allow them to drill deeper in harsher environments. These projects are driving an increasing requirement for analysis and design tools that are more reliable and, crucially, more predictive than previously used systems.

Speaking at the recent International Oil and Gas CFD conference, organised by Ansys, Raghu Menon of Shell Global Solutions confirmed that his organisation believes simulation-based engineering can play a key role in helping it to achieve its objectives. More capital is at risk than ever before, said Menon. Companies have to make decisions faster - and these decisions must be based on more accurate information, he explained.

“CFD [computational fluid dynamics] offers high fidelity information on flow based on first principles and can be applied to any process or equipment, regardless of its geometry,” said the Shell executive. “It can also be used for scale up and scale down.”

Menon acknowledges there are problems, both computational and modelling, but believes simulation technology offers a robust route to increasing the viability of information for making decisions on projects.

At the same event, Derek Colman of BP Petrochemicals noted that CFD codes have only recently been developed for multi-phase flows and complex thermodynamics.

The emergence of viable multi-phase modelling capability is increasing the potential of CFD, for example, in predicting the performance of fluidised bed reactors, where the interaction of multiple phases are not well known.

BP Petrochemicals is currently focusing on CFD model validation and closure development, which is similarly critical to gas/liquid systems. Even with first approximations in models, the results are providing the businesses with performance benefits, Colman said.

According to the BP expert, the challenge now is to increase penetration of CFD within the process engineering community, with BP looking to enable non-CFD users to have access to CFD models for evaluating, for example, process chemistry on a set-up flow model.

Working with Fluent, BP has developed a customised front-end capability that allows the user access to selected parameters within the model - feed flow rate and composition, reaction constants, for example. The model can then be run from the customer’s PC on the Fluent Remote Simulation Facility and they can retrieve the results without obligating the need for a local license.

“CFD is clearly here to stay and grow within the petrochemical industry as more people want to have access to it,” concluded Colman. “The challenge is to manage that growth and ensure the expectations of management, the skills of the users and the capabilities of the package are understood and compatible.”

While simulation models can increase operators’ understanding of processes at all stages from reservoir to pipeline, another aspect of the technology involves converting the data into better decision-making.

Process modelling can provide improved understanding of what a company could be doing by interfacing with data collection and management systems, BP’s Patrick Calvert told his audience at a recent Institute of Asset Management conference.

Applications, said Calvert, should therefore be modular, based around a common framework and be available to personnel at all levels. “Any model that is easier to use and whose results are easy to interpret will gain more traction and hence lend itself to being sustained,” he stated.

Technology models, continued Calvert, should be placed on-line to improve their accuracy, while levels of trust placed in a model can be increased by trending against real plant data.

The challenges for BP are its size and business unit-managed structures, which can lead to duplication of effort and standardisation issues. There are also other issues in terms of third party simulation providers, the availability of skilled resources and management of change, said Calvert.

Among suppliers of simulation technology, Honeywell has been active in developing its position by integrating technologies gained through the acquisition of UniSim technology and a partnership with Petroleum Experts of the UK.

UniSim can help engineers create steady-state and dynamic models for plant design, performance monitoring, troubleshooting, operational improvement, business planning and asset management. IPM online tools support design of complete field models of oil or gas production systems.

In a recent interview, Phil Millette, who is in charge of Honeywell’s Saudi-based Aramco business director, told PE: “There is tremendous growth in everything we do around simulation production for all kinds of production facilities, whether it is for oil platforms, LNG facilities, everything.”

According to Millette, growth encompasses simulation technologies for both dynamic purposes and steady-state applications. “Dynamic is more of a challenge but people are seeing more of a direct use in areas such as safety, environmental performance. That’s driving the use of this complete incubator environment that we provide to represent the plants.”

New demand for OTS (operator training simulator) technology is also highlighted by independent supplier Hyperion Systems Engineering, which is to perform a large number of dynamic simulation studies for major corporations in conjunction with ENI Snamprogetti. They will be carried out on gas gathering compressors at three pressure levels - atmospheric, low pressure and high pressure - under a wide range of conditions.

“This will enable engineering management to verify in advance the performance of the plant during the engineering phase and before construction,” said Dean Jones, Hyperion’s vice president for modelling & simulation solutions.

Invensys Process Systems, meanwhile, is supplying PetroChina Dushanzi Petrochemical Co. with its Sim Sci-Esscor (OTS) for the chemical section of an integrated refinery and chemical revamping project to process imported sour crude from Kazakhstan.

The project includes process modelling of six chemical section units, along with integration with emulators for the DCS, safety instrumented systems and PLCs. The Chinese major will use the OTS to enhance operator knowhow, shorten start-up and shutdown periods, and reduce off-spec production.