Field located computers are becoming more common in the oil producing industry. Although hardware reliability has been greatly improved, some special provisions must be made for field installed systems. The system for the Wabasca in-situ heavy oil recovery pilot is outlined along with the data gathering, process alarming and report generation functions. Applications and areas for future process control are discussed.
The Wabasca heavy oil deposit covers about 180,000 hectares (460,000 acres) and contains approximately 8 billion cubic meters (50 billion barrels) of 5.6 ° API gravity crude.
Gulf Oil Canada Limited has been active in the Wabasca deposit since the winter of 1973. Our objective is to develop technology for the economical extraction of heavy oil from the sand.
The initial two well experimental program was expanded in 1974 with the drilling of 15 wells. the installation of surface facilities, including a fully modern camp, and the construction of 16 miles of all weather access road.
The camp is self sufficient except for provisions. Water and sewage systems were installed and electrical generators provide power.
Initial experimentation was with cyclic steam stimulation. Other wells have been drilled for other tests, such as steam drive and steam-solvent injection. A steam drive project is being carried out on a condensed inverted 5-spot pattern. A fireflood pilot was constructed consisting of one air injection well, four producing wells on 1/5 hectare (½ acre) spacing, and six temperature observation wells. Our computer system was designed for this pilot.
The pilot site is located approximately 320 kilometers (200 miles) north of Edmonton. Access to the site, from Edmonton, is 1 hour via chartered aircraft, or a seven hour drive over roads, varying from pavement to very poor gravel. With such access, the pilot site is considered a remote location.
From pilot inception, data has been manually recorded on preprinted forms. This method of data recording has not been entirely satisfactory. Up to two weeks time is required to transport the data sheets, edit, transcribe, keypunch and list the data in a format amenable to analysis. This system is very labor intensive and adds substantially to the cost of tile data. Often, analysis of the data and process evaluation is hampered by the recording of transient data as steady state values. Occasional unsteady state conditions go unrecognized as such and short term transient data is ascribed to a longer time period.
In the past, computers were assembled using vacuum tubes and occupied whole rooms. They were temperamental, intolerant of environment and required a large capital investment for hardware.
The transistor decreased the size of computer systems and the development of today's integrated circuit technology has further reduced the physical size of computers while making them faster, cheaper, more reliable and dramatically expanding their capability. The improvement in hardware reliability makes it possible to install these systems in remote locations, such as our Wabasca pilot, and it is common today to find computers operating in hostile environments.
