Web-based system connects monitoring to remote sites
Total, Marathon, and Talisman are using a suite of Web-based tools that incorporates a production monitoring system to ensure remote oilfields can use an Aberdeen skills base.
Testing the limits
Xplore allows operators to optimize production by improving process performance and reducing both downtime and maintenance costs. The Web-based application allows anyone with access to the operator’s network to log on from any location to make informed decisions on the production, integrity, safety, and environmental aspects of individual installations. This remote monitoring ensures that the engineering skills base clustered in Aberdeen, Scotland, can be used on remote oilfields in places such as Nigeria and Gabon.
The program can work with compression, gas turbines, separation equipment, produced water, heat exchangers, pumps, pipelines, hydrocylones, virtual metering, and emissions, developer Xodus says.
An example of the Xplore compression module user interface.
“Xplore is easy to roll out and easy to use,” says Andrew Jones, Xodus technology manager. “It has been designed to provide real benefits in terms of meeting clients’ key performance indicators: safety, environmental, and economic. Although Xplore has a number of generic modules, each application is custom designed. We aim to work with our clients to determine key business drivers and to incorporate these into the design.”
An overview of the entire compression facilities at the click of a button.
Xplore has a number of unique generic calculation modules to monitor process equipment. These include compressors, heat exchangers, hydrocyclones, separators, gas turbines, pumps, and pipelines. Each can be tailored and linked to provide a bespoke solution for each installation.
As an example, Xplore can monitor compressor performance to improve compression system availability and to maximize production. A simple system can be expanded to include emissions monitoring from a gas turbine to help reduce emissions and to meet environmental targets.
Compression monitoring
“With the Xplore system, we are empowering our clients by giving them the tools to fully understand their processes and enabling them to make more informed decisions,” Jones says. “Knowing very clearly where the constraints of their processes lie allows our clients to maximize the performance of their facilities. Where operators and onshore engineers previously only had access to a limited dataset, Xplore is delivering masses of invaluable information in real time. Now, all personnel are getting the same clear and accurate picture. Compression monitoring is no longer the exclusive domain of the experts.”
The system recently was deployed on a North Sea asset to monitor key compressors. “Its success is evident. The client has already placed a further order to expand on this investment by the addition of a second facility,” says Jones.
Process and control
Xplore monitors the process and control aspects of the compressors 24 hours per day, seven days per week to allow the operations team to focus on other production areas.
The compression module gives the user the ability to view a large amount of system data and complex calculated information in real time. Such information normally is available after offline studies. Typical available plots are Operating Point versus Design Curves for Polytropic Head, and Efficiency and Power versus Flow. Other options include head, ΔP, compression ratio, and discharge pressure. Flow can be viewed as actual or standard flow. Plots also can show control lines.
Composition can be updated using an online chromatograph, if available. Otherwise, it can be entered manually, with molecular weight reconciliation performed over time.
Pipeline monitoring
“Monitoring pipeline operation is the final piece of the jigsaw for Xodus,” says Jones. “We already offer a truly integrated subsea and facilities design service, and bringing in a state-of-the-art monitoring system to optimize pipeline operation elevates our offering to an unprecedented level.
The Xplore pipeline module overview user interface.
“One project we have recently installed allows us to track gas compositions through the pipeline. Therefore, we can optimize arrival conditions to maximize gas throughput. It also removed the need for the client to purchase an expensive online gas chromatograph to track compositions for commercial allocation purposes.”
The Xplore pipeline monitoring system offers a variety of operational parameters such as pipeline operating conditions, pipeline thermo-hydraulics, pipeline capacity versus usage, pipeline integrity, wax management, and hydrate management. All operational parameters are shown in real time and also can be trended. In addition, calculation engines allow a predictive function to provide a view of options analysis into the future.
Business benefits
Xplore has been designed around adding business benefits across all key safety, environmental, and economic performance indicators (KPIs). Although there are several generic modules, each is bespoke and therefore custom designed.
Slugging behavior calculations.
For example, Xplore can monitor and improve compressor performance to improve compression system availability and to maximize production. A simple system like this can be expanded to include emissions monitoring from a gas turbine to meet IPPC regulations and hence assist operators to meet environmental targets.
Xodus believes the business benefits offered by the system are far reaching:
- Real-time process monitoring - Presents a large amount of data through the one integrated, generic interface; presents calculated system data in real-time; and real-time, historical, and predictive trending of any system parameter.
- Predictive capability - Warns in advance of potential process upsets; and anticipates the need to modify operations.
- ‘What If’ functionality - Conducts hypothetical dynamic studies
- Promotes process performance enhancement - Improves production; reduces downtime; and reduces maintenance costs.
- Modular design - Allows efficient build of bespoke systems based on generic calculation and system modules.
- Capital savings - Provides a possible alternative to the installation and maintenance of new capital equipment.
How it works
Xplore operates alongside existing control systems and data historians, taking real-time data and using the data to provide enhanced information about equipment and system operation. OPC technology collects real-time data from DCS systems and historians such as PI, PHD, or IP21. Data is filtered, then stored in the database. In addition to the real-time data, each application can contain several configuration parameters such as compressor curves, valve CVs, etc.
Configuration data and real-time data are used to predict unit operation or system module performance. The calculated data is then stored in the database.
The Xodus Data Manager, XDM, is the core of the Xodus production monitoring and optimization product. XDM controls the data flow from any control system or data before storing it in the real-time database. It also communicates with live process historian through to the Xplore database. Data transfer uses OPC technology to facilitate connections to any OPC compliant system. XDM filters and reconciles data. The XDM also communicates with the Xodus Simulation Manager (XSM). Data transfer between XDM and XSM is in most instances through OPC. In some circumstances, a proprietary driver must be used.
XDM controls the Web-based graphical user interface. Graphics, trending, messaging, alarms, and configuration are handled via XDM resulting in a true thin client application accessed via the Internet Explorer browser.
XSM operates in conjunction with the XDM. XSM links to most simulation packages such as Hysys, Olga, Aspen Hydraulics, Pipesim, Multiflash, Prosper Gap using OPC connectivity, or bespoke data transfer tools. XSM controls simulation runtime, convergence, solution times, solution robustness, data reconciliation, and data flow to the XDM.
“One key differentiator of this system is the fact that it is a true thin client application,” says Jones. “In simple terms, it means that deployment of the system is straightforward, requiring nothing more than authorized access to the local area network and a standard Internet EXplorer Web browser. No extra plug-ins are required.”
“We’ve taken the pain out of something that was historically notoriously difficult to implement. Most IT infrastructures are necessarily steeped in security meaning that installation, upgrades, and administration of new systems could be very difficult, to say the least. Clients have embraced the simplicity of the concept.”
The pipeline system offers specific benefits
Production operators
The majority of the time, the operator uses Xplore in real-time mode. Operators can use Xplore as an advanced operating manual. It advises on startup times, blowdown requirements, chemical requirements, operating regime (including hydrate management), accurate flowrates, available pipeline capacity, and system constraints.
Production engineers
The simulation models or calculation modules at the heart of Xplore offer a picture of what is happening in the pipeline. Benefits include:
- A full thermo-hydraulic view where changes in pipe wall thickness due to scale or wax are picked up
- Erosion and corrosion calculations provide a detailed picture of pipeline wall thickness/ wastage
- Slug regime prediction. An online model provides a picture of what flow regime the pipeline has. This is particularly useful if the pipeline conditions are changing, for example when water cut increases
- Accurate prediction of well head flowing pressures.
Project engineers
The system can provide subsea engineers with an up-to-date view of the state of the pipeline. They can use the “what if” analysis to view the effect of increased CO2 or changes in separator pressure.
More simply, Xplore can provide operating data to the design team. Topsides engineers access the same data as the subsea engineer, so a consistent design basis can be achieved.
