The success of stimulation (fracturing) treatments can be greatly improved by using real-time modeling and optimization techniques.
With increasing workloads in the office and budget restraints, both service and producing companies search for more cost effective and reliable alternatives to on-site fracturing engineering. One alternative is to monitor a fracture from the home office using communications to deliver the required real-time data.
With limited coverage in many areas of Western Canada, cellular communications is not consistently reliable. As a result, communications shifted to geosynchronous satellites and new technology was developed to allow remote, real-time monitoring and optimization of well site stimulations. The new technology addresses the major issues such as data integrity, communication protocols, and confidentiality.
To date, in excess of 300 treatments have been monitored using the satellite system. A case study for a stimulation treatment was conducted and is presented.
As with most companies who are involved with production, oil and gas producers are constantly looking for ways to improve productivity and reduce costs. This applies to all phases of well development including hydraulic fracturing treatments.
Major gains in productivity were achieved with the introduction and evolution of computer systems as part of the fracturing process. Computers provide the tools for data collection and treatment analysis. Data collection computers used in conjunction with real-time modeling software give the service company the ability to generate a downhole "picture" of the fracturing treatment. Along with a downhole picture, the modeling software generates trends that allow engineers to make "on-the-fly" changes to a treatment for optimum results. Engineers at the well site interpret the data being modeled and provide guidance during the fracturing process.
Further gains in cost reduction and productivity would occur if the engineers who guide the fracturing process did not have to go to site but could guide from head office. The client and engineering staff would then monitor the fracture process as it was occurring without having to make expensive field trips.
To gather and display data from a stimulation treatment (Figure 1), a PC-based, software package (1,2) is used which gathers data from a number of site instruments. As it is gathered, the data is displayed and evaluated by using real-time software modeling packages(3,4). The modeling packages reside on a separate PC. The data gathering PC communicates with the modeling PC through an RS-232 port. The data being transmitted is in an ASCII record format and has no protocol for integrity nor any data flow control.
To allow the engineers to guide the fracturing process more efficiently, the modeling PC was moved to the home office.
A fundamental requirement becomes reliable communications between the data gathering PC on site and the modeling PC in the office.
Cellular and satel1ite communications were both investigated. Since well sites are typically in remote areas where conventional communications such as telephone and cellular may be unavailable or unreliable, geosynchronous satellite systems were given preference.