Onshore Gas Field Solutions

Executive Summary

eP provides solutions for onshore gas fields that:

• Greatly reduce nonproductive travel time to wells.
• Eliminate the possibility of wells or facilities being down unnoticed.
• Electronically collect data for reports.
• Provide limited after-hours alarming through an answering service.

The solutions provide the tools and equipment that allows the user to trend any of the data received from the field, which allows wells and facilities to be serviced before a failure occurs, further reducing downtime and the resultant production loss. By collecting data and interfacing it with reporting software, users are able to eliminate the cost of further accounting procedures.

The information is available company-wide in a timely fashion to any department that needs it. The data can be analyzed from anywhere and combined with any information, such as EFM data.

The information is recorded in daily and monthly reports. In addition, the information allows the operator to make accurate nominations for the pipelines. If there is a problem after hours, alarming functions and remote access to data allow supervisory personnel to determine the most cost-effective way to handle those field situations.

Overview

eProduction Solutions versus a Typical Onshore Gas Field Solution

Onshore gas field operations typically handle day-to-day activities by storing historical information about the performance of the field, the accounting numbers of the field and each well, required reports for corporation and well owners, and nomination amounts for the pipelines. Frequently, this information is stored in separate applications, spreadsheets, and databases. The disparate methods of storing this information make it increasingly difficult for the field manager to grasp an overview of the field's operation. Accurate nominations are difficult, and shrinkage analysis is delayed.

eProduction Solutions

eProduction Solutions uses software as part of an integrated solution that allows users to move and combine data into a format where informed decisions can be made from one application. The information for production analysis, shrinkage analysis, and nomination tracking is all located in one application and the user can see all the data on one screen.

Case Study of the csLIFT system

This study describes the software system a major oil company's large South Texas gas field now uses to monitor and optimize production. Using a software solution for data acquisition and integrated analysis allows operators of the field to have accurate data on well production, more accurate nomination tracking, and immediate material balancing.

The field has 320 gas wells and 9 facilities that are now on the system. It monitors 19 remote terminal units (RTUs), 16 sales points, and 18 compressors in a field that produces an average of 240 million cubic feet of natural gas-per-day. The users of the system are able to add and modify wells and facilities to the software system as needed.

The goal of the project was to use available technology to reduce operating costs, increase production through reduced downtime, increase employee productivity, and improve safety across the field.

Implementing the system has resulted in reduced costs and increased production. The benefits of implementing the system include: more accurate gas volume nominations, increased efficiency in discovering shrinkage in the field, greater production due to a decrease in the downtime of compressors, more accurate production forecasts using G-10 data, the enabling of call-outs from the software after hours, and optimized work processes for employees.

A Problem of Distance

The 320 wells and 18 compressors of this South Texas field are spread over a wide area, none of which is close to the company's Houston office. Some wells are 50 miles from the field office. Physically checking the wells or facilities would cost greatly in nonproductive travel hours and miles. The large amount of road time required for this system would increase the likelihood of accidents or breakdowns on the road. Being limited to in-person inspections would allow the possibility of extended downtime for a well or compressor before it could be discovered and repaired. Manually calculating production and other field-generated numbers from this number of wells and sales points would be time consuming and would increase the possibility for mistakes (transposition of numbers, etc.).

Some type of computer monitoring and control would be necessary to maximize productivity and reduce the opportunity for error. For approximately 12 years the company had used a Supervisory Control and Data Acquisition (SCADA) system to provide real-time monitoring of these points as well as collection of production data. While this did increase employee productivity, allowing them to check only locations with known problems, and reduce downtime by quickly alerting the operator of the existence of those problems, there were three areas in which the company needed their system to do more.

1. Data accessibility. Only a few employees at the field office had access to the data. It still had to be manually transferred to accounting software for nomination tracking, sales history, and other bookkeeping functions, which still created opportunity for human error. Manually performing all those functions was very time consuming, reducing efficiency of personnel.

It also meant that anyone in the engineering or accounting groups who needed production data at the corporate office in Houston had to call the field office. They then had to hope someone who could access the system was there with time to dictate numbers over the telephone.

2. Speed and accuracy in reporting. Because of the time delay and human factors in point one, nominations (estimates of gas to be delivered to pipelines) took longer and actually involved estimates in order to conserve time. It was said, "We had to guess, and we hoped we guessed right." The company needed software that would take extensive data, perform all the necessary calculations, and provide reports quickly, completely and accurately to avoid the possibility of costly penalties from the state regulatory agency due to inaccurate nominations.

3. Historical data. The previous system operated on a computer containing only an eight megabyte hard drive and two megabytes of random access memory (RAM), meaning it could hold only one day's data at a time. Trending, graphing or any function involving historical data was not possible on this computer. This meant the system could not generate any report that would warn operators of a slow decline in production from a well or a compressor, indicating the onset of a major problem. Only after a well or compressor shut down could a crew be dispatched to effect repairs, meaning the facility would produce nothing while the crew drove as far as 50 miles to the site before beginning work.

The Network Solution

A PC-based system seemed to be the solution because of its ability to tie in with the company's network, as well as the added memory and reporting functions available on PCs. The company decided to purchase the csLIFT field automation software from Houston-based Case Services because it is PC-based, offers extensive reporting capability and it allows company personnel to easily make changes in wells and facilities to reflect changes in the field. The system was up and running in September of 1997. The new software resolved the three main requirements in the following manner:

1. Accessible Data. csLIFT puts data on a server, which is part of the company's wide area network (WAN). This allows data access from any PC on the WAN in the Houston office, eliminating the need to make a telephone call and take dictation and also freeing field personnel to concentrate on solving problems.

The data interfaces with the company's accounting software, which has saved hours of clerical costs, as well as eliminating the possibility of human error in the transfer process.

Multitasking functions allow field personnel to open multiple screens at once, giving a broad overview of conditions at multiple wells, RTUs, facilities, and compressors. Personnel can be dispatched quickly to investigate any abnormalities.

Complete data can also be accessed from a PC or laptop by simply dialing into the system. When the software detects an alarm situation outside of normal business hours, it uses Win911 to page a designated employee who can then dial into the system and determine what, if any, attention is needed in the field. The previous system alerted an answering service, which then paged the supervisor who then had to go to the office to discover what the problem was. The company expects to eliminate the expense of the answering service in the coming months.

The operator can see the status of the facilities, wells, and alarms

2. Fast, accurate reporting. Because field data is immediately available to accounting and reporting software without manual input, any reports can be generated quickly and as needed. The PC does the complex calculations involved in accurate nominations as well. The company's nominations are reported to have been "dead on" since the changeover, greatly reducing their exposure to the risk of penalties. G-10 data can be used to forecast production and to quickly determine the presence and exact location of problems.

This production report uses downtime to accurately calculate
shrinkage and do nomination tracking.

3. Historical data allows trending. The biggest benefit for field personnel has been the ability to use historical data to track compressor functions, including fuel use and gas volume processed. For example, if over a few weeks' time a compressor's fuel use increases while it moves no additional volume of gas, a crew would be sent to the site to inspect it and make any necessary repairs before the unit failed completely. This has greatly reduced lost production due to down time. It has also allowed field personnel to more efficiently plan their work schedules, doing this preventive maintenance by area and relative urgency, rather than in a "drop everything" mode.

Operators can easily compare compressor fuel usage
to gas processed with historical trending

Conclusion

For years, this company's csLIFT based software system has shown the following economic benefits:

• Greatly reduced nonproductive travel time to wells
• Eliminated the possibility of wells or facilities being down unnoticed
• Electronically collected data for reports
• Provided limited after-hours alarming through an answering service
• A recent upgrade to a more complete field monitoring system helped them further control costs by:
  • Trending data, which allows wells and facilities to be serviced before a failure occurs, further reducing downtime and the resultant production loss
  • Collecting data and interfacing it with reporting software, eliminating the cost of further accounting procedures
  • Making that data available company-wide in a timely fashion to any department that needs it
  • Processing that data in accurate reports including nominations
  • While replacing outdated RTUs, several different types of RTUs are being test by simultaneously connecting them to Case Services' software
  • Providing detailed after-hours alarming functions and remote access to data, which allows supervisory personnel to determine the most cost-effective way to handle field situations

The company has already experienced production increases because of reduced downtime, made their employees more productive, has reduced its exposure to penalties based on inaccurate nominations, and expects to eliminate the cost of an answering service.

Real-time Applications

eP uses software as an integral part of the onshore gas field solutions. The architecture of our software products allows for comprehensive monitoring and control of gas production operations. The software provides general monitoring for virtually any controller, RTU, or PLC. All wells, compressors, and facilities in the field can be easily monitored from one screen anywhere on the network. The software can communicate through radio, cellular, satellite, and hard wire.

The point-and-click interface of the software provides the ability to easily define RTUs, analogs, meters, and discretes so users can start seeing trends, alarms, and reports in minutes. Users can easily add calculated analog, meters, discretes, and alarms for instant notification of problems. The software is a hardware independent system that works with most all popular controllers, RTUs, and PLCs. Because it can talk to multiple protocols over a single radio frequency, a user of the system can avoid licensing multiple frequencies for a field. It can monitor virtually any controller, RTU, or PLC with a native protocol or through OPC standards.

This software goes beyond monitoring by providing flow AGA calculations for RTUs that do not calculate flow amounts internally.

A built-in data historian provides the user with a long-term trend of the performance of the compressors. The trends can immediately be seen in graphical trends for long-term analysis.

Manual Entry Applications

For locations without communication capabilities, the data can be manually entered into the system. A sophisticated synchronization system assures that data is not inadvertently replaced or mishandled.

Artificial Lift Applications

eP's systems go beyond merely monitoring the status of wells, the system provides software for optimizing artificial lift operations through automation and analysis. Each type of artificial lift has a specific software tool that has specific analytical features to optimize the production of that type of well. These tools includes analysis for artificial lift methods that are used with gas fields. These include software that can be used to optimize sucker-rod pumping when it used to pump water off a gas reservoir. If water floods are used, a software package is available that can be used to maintain an accurate amount of water injected. In addition, there is software that is used to monitor plunger lift operations.

Facilities Monitoring Applications

An operator can see an overall look at the field with specialize production software. Rather than merely display readings from analogs, meters and discretes, this software displays real-time information divided into wells and facilities. Reporting on well production, nomination tracking, shrinkage, and material balancing are simplified and condensed into one application. The result is more efficient operations and reduced time in identifying problems such as leaks.

If a field is using well test facilities to monitor production from the producing wells, eP offers a software package as part of the solution. Automatic, semiautomatic, and manual well testing can be controlled and monitored with eP's software.

Enterprise Information Management Systems

The information from a gas field can be seen anywhere in the organization through the company's Intranet or the Internet. eProduction Solutions uses Case Services' web software which allows anyone with permission to access the real-time information from the wells and facilities. An employee of the operating company or an owner of a well can monitor all the wells, compressors, or facilities, compare the information to historical data, and study predictive trends all from another part of the world.

Using this software to access gas fields allows the user to combine real-time information from onshore gas field operations with other information from multiple databases and applications. Financial, operations, and maintenance data can all be displayed simultaneously while browsing through different areas of a gas field.